The Technologist May 2018 by Dental Technologists Association

ition d E y r iversa

nn 10th A

volume 11 issue 2 may 2018

issn 1757-4625

the

technologist the official journal of the dental technologists association

5.5

HOURS OF VERIFIED CPD

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guesteditorial

■ welcome Dear Colleague Congratulations to the DTA on its 10th anniversary of the launch of The Technologist! (TT) Summer 2008 saw the birth of a completely new journal, aimed at providing the professional support, CPD and advice that DTA members needed. Back in 2008, dental technology had just gone through a major transitional period resulting in professional registration and regulation with the General Dental Council. With these changes came new requirements placed on dental technicians, including the need for professional indemnity insurance and the requirement to actively engage in and take record of our continual professional development (CPD). The DTA saw these challenges coming and decided that it was time to move away from our featured pages within another publication and gain full autonomy and editorial control of our very own publication, which was something that hadn’t existed prior to then. As DTA president at the time, and with the support of the DTA management company, our awesome DTA committee members and the superb talents of our newly recruited editor, Vikki Harper, we set out our vision for TT and what we wanted it to achieve. I am sure over the last 10 years we have realised the ambition that we had then for TT and more. We also took the opportunity to broker and introduce our very own indemnity package and this was launched in the very first copy of TT for the benefit of members. This membership benefit has gone on to give DTA members a great value for money indemnity insurance covered by one of the UK’s leading insurers. Through the last 10 years of TT the publication has provided DTA members

with an incredible amount and variety of high quality verifiable and non-verifiable CPD, including articles covering all of our core CPD requirements. Articles have been submitted from leading dental technicians from across the world, academics and members of our own community. We’ve had expert nontechnical advice covering topics such as the latest technological innovations, business development advice, GDC and MHRA compliance, legal and ethical considerations and obligations, and personal and professional standards. TT has kept you up to date and informed with all of the current political and regulatory issues of the day. Each issue of TT has historically been published in a bi-monthly format, but will be moving to a quarterly publication from this edition. In practical terms this will mean that your TT journal will be a whopping 40 pages of all that is current and jammed full of cutting edge subjects that matter to all dental technicians. You will also notice in this edition that the completion of your CPD is now only available online. All things change and this will help streamline the process enormously, saving the DTA time that can be focused on more proactive member endeavours. If you’re having difficulty with the online approach, please call Sue at the office and she will do all she can to assist.

articles featured in TT from this edition onwards will be subject to a thorough process of peer review. This will ensure that the exacting standards and high quality of our publication are maintained and that your CPD articles are fully compliant with the new GDC guidelines of August 2018. The DTA will continue to keep you at the forefront of current thinking in dental technology, keeping you up to date, for example, with the digital dental revolution, advances in technology, materials and workflow patterns that will eventually change every aspect of our daily working lives. TT will strive to make this transition one that benefits you as an individual technician or a laboratory owner. Thank you for your highly valued and ongoing support. I hope you all enjoy the read. Please lend us your thoughts on the new approach! Paul Mallett DTA President 2007–2009

In line with the introduction of ECPD and the changes that has instigated, the CPD the

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2 may 2018

in this issue the

technologist Editor: Vikki Harper t: 01949 851 723 m: 07932 402 561 e: vikki@goodasmyword.com Advertising: Sue Adams t: 01452 886 366 e: sueadams@dta-uk.org

DTA administration: Sue Adams Chief Executive Kestrel Court Waterwells Drive Waterwells Business Park Gloucester GL2 2AQ t: 01452 886 366 e: sueadams@dta-uk.org DTA Council: Delroy Reeves President John Stacey Deputy President

dta column

news

in conversation â&#x20AC;&#x201C; 10 years already

hr facts: why did they leave?

CPD

what are your responsibilities as an employer?

CPD

making tax digital

CPD

can we fix it? consent considerations for denture repairs

CPD

it fits too well: the modern problems with CAD/CAM technology and resin bonded bridgework â&#x20AC;&#x201C; A case study 17

CPD

anniversary pull-out medical emergencies in a dental environment

Tony Griffin Treasurer John Stacey Gerrard Starnes Marta Wisniewska Social media coordinator

provision of a maxillary complete denture and complex mandibular unilateral free-end saddle cobalt chromium based partial denture

Editorial panel: James Green, Tony Griffin, John Stacey, Editorial assistant: Dr Keith Winwood

Design & production: Kavita Graphics t: 01843 583 084 e: dennis@kavitagraphics.co.uk

CPD

25 CPD

developments in hybrid ceramics for CAD/CAM manufacturing

A line-up like no other at DTS 2018

Getting To Know You ...

The Technologist is published by the Dental Technologists Association and is provided to members as part of a comprehensive membership package.

Published by: Stephen Hancocks w: www.stephenhancocks.com

For details about how to join, please visit: www.dta-uk.org or call 01452 886 366

Find out the 11 reasons to join DTA by visiting:

ISSN: 1757-4625 Views and opinions expressed in the publication are not necessarily those of the Dental Technologists Association.

www.dta-uk.org the

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Cost effective professional indemnity insurance for dental technicians and laboratories

Tel: 01634 662 916

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thedtacolumn

The DTA Column DTA’s nominated charity for 2018 – Den-Tech Andrea Johnson, Chair of Den-Tech, explains what Den-Tech is and why they are so excited to be working with the DTA in 2018. When asked to describe Den-Tech, Andrea explains that Den-Tech is a charity concerned with relieving poverty through the provision of affordable dental appliances to those patients who are in need and unable to afford treatment. This applies both in the UK and abroad. She says, ‘We must look after those most vulnerable within our society, the ones that find themselves unable to access these services. Everyone, regardless of stature or position, is entitled to the basic human right to be able to eat properly and smile without shame or embarrassment and if I and all the other brilliant technicians around this country can help at all then we should and I am very proud to say that the UK techs have answered the call and are pulling out all the stops to help us to make a difference.’ This drive and enthusiasm was put into action fully for the first time over the Christmas period in 2017. Through working with homeless charity, Crisis, Den-Tech set up its first ever field lab alongside the Crisis at Christmas clinical dental team. The dental clinical team has been established with Crisis for 10+ years but has to date never been able to offer restorations to its homeless patients. Over the period of the week, the Den-Tech team of volunteers provided 24 same-day dentures: a massive achievement when you

take into consideration the fact that the team were working in a very basic makeshift dental lab housed in a school science laboratory. It would not have been possible without the support of all the wonderful techs who gave up their time over the Christmas holidays to volunteer to make the dentures, and the other fantastic technicians and companies who donated supplies and equipment to get this project off the ground. Crisis dental service volunteers shared their views of the new denture service and explained that it was ‘amazing to make people feel great – it really was lifechanging for people’ and that they were ‘surprised and thrilled to ﬁnd we had a technician on site’. This new project, in addition to the existing overseas ones, has received a fantastic amount of support from the dental technician community who are pulling together to provide a full range of dental technology services free to those most vulnerable and needy in our society. Working with the support of the DTA this year will help us get our message out to the larger community of technicians and also give us the wonderful opportunity to heartily thank every single one of those techs and companies who have helped so far. You are all truly wonderful!

Den-Tech volunteer Suzie Owen advising volunteer dentist

Those who actively support us also get the exclusive use of our supporters’ logo to display on their web pages, literature, Facebook pages, etc., so please look out for this as you will know that each one of them is a good person/company who has gone out of their way to help make this world a better place. If you would like to become one of our supporters, and also receive your copy of our supporters’ logo, please do not hesitate to get in touch and see how you can help. It is together that we are stronger and together that we can make a difference to the lives of those less fortunate. Find us also on Facebook & Twitter.

If you would like to come and speak to the Den-Tech trustees in person, please come and see us on stand E05 at the Dental Technology Showcase in May.

Den-Tech trustees Edward Mapley and Andrea Johnson hard at work

Also, if you would like to know more, volunteer your services, donate equipment and supplies, make a donation or get involved in a sponsored event to help raise funds, please visit our website www.dentech.org or email dentech.chair@gmail.com

Lower partial denture before and after the

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4 may 2018

news&information

■ ECPD – WHAT DOES IT MEAN FOR DENTAL TECHNICIANS? What is ECPD? Enhanced Continuing Professional Development, or ECPD for short, is an enhanced version of the CPD currently in place for all dental care professionals and is being introduced by the General Dental Council.

What are the main changes from the current CPD? There are five important changes you really need to be aware of: ■ The removal of non-verifiable CPD – meaning an overall reduction of CPD hours for DCPs. ■ A requirement to make an annual declaration of completed CPD hours. ■ All registrants must have a personal development plan (PDP) and a log of activity. ■ A requirement to align CPD activity with the GDC’s ‘new’ development outcomes. ■ A requirement for DCPs to plan CPD activity according to their own ‘field(s) of practice’.

So, how many CPD hours does a dental technician need to do in future? For dental technicians the minimum per 5-year CPD cycle is 50 hours. For clinical dental technicians the minimum per 5-year CPD cycle is 75 hours. To encourage you to do regular activity, there will be a minimum of 10 hours CPD for every two consecutive CPD years.

When does ECPD come into effect? These changes come into effect on 1 August 2018 for all dental care professionals, except dentists, for whom it takes effect from the 1st January, 2018.

What should a personal development plan look like and what is an activity log? You can design your own personal development plan (PDP) and activity log if you want, but the quickest and simplest approach is to use the templates designed by the GDC which you can find here: ■ PDP: https://www.gdc-uk.org/api/files/ PDP%20blank%20template%20FINAL .docx ■ Activity Log: https://www.gdc-uk.org/ api/files/Activity%20log%20blank %20template%20FINAL.docx

What are the GDC’s new learning outcomes?

the

your professional needs, field of practice and the standards for the dental team before deciding on the right CPD activity for you. In this way, the GDC believes the activity will become more meaningful and relevant to the areas that you feel need to be maintained and built upon.

As you will know, the Standards for the Dental Team set out the ethical principles of dental practice, and in ECPD these standards are at the forefront of CPD planning and activity through four development outcomes; from August 2018 you will need to map each of your activities to at least one development outcome.

How to find out more

As before, there is a list of recommended topics which currently looks like this:

How can DTA help you?

■ Medical emergencies ■ Materials & equipment (dental technicians) ■ Complaints handling ■ Safeguarding children and young people ■ Disinfection & decontamination ■ Legal & ethical issues ■ Oral cancer: early detection ■ Safeguarding vulnerable adults GDC’s plan, do, reflect, record model encourages you to proactively think about

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GDC’s ‘Plan, Do, Reflect, Record’ Model

■ If you’d like to know more, go to https://www.gdc-uk.org/ professionals/cpd/enhanced-cpd ■ You can also watch a short YouTube video and download GDC’s guidance document for all DCPs by visiting https://www.gdc-uk.org/ professionals/ cpd/enhanced-cpd

At DTA, we’re keeping a close eye on ECPD and how it will affect dental technicians, and during 2018 we’ll be announcing a range of support exclusively for our members as ‘go live’ date approaches. So, watch out for more details on our website – www.dta-uk.org. In the coming months you will notice changes to the way that CPD is presented in both The Technologist and Articulate in preparation for the introduction of ECPD; this will include providing links to the new development outcomes and peer review of articles.

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Annual Conference 2018 Hosted by the Orthodontic Technicians Association Park Plaza Hotel, Nottingham,14-15 September Dear Colleague This year’s conference, hosted by the OTA and in association with Future Labs, the Dental Technologists Association (DTA) & the Society of British Dental Nurses (SBDN) will be held in the fabulous city of Nottingham for the first time ever. The old medieval town of Nottingham grew up around its castle and market place, which is now at the centre of an extensive

shopping district, with two large indoor centres plus a wide range of branded chain stores and many smaller independent outlets. At the heart of the city is the old Market Square, one of the largest market places in the country. With up to 10 hours of verifiable CPD available, the conference venue will be the 4* Park Plaza hotel which is situated in the heart

Confirmed speakers include:

Lesley Sharpe Medical emergencies Jutta Ruffing Burnout prevention – the way to smile George Antonopoulos The future of dental technicians’ concepts and work Nicolas Miedzianowski-Sinclair Digital orthodontics: choices, obstacles and limitations Fiona Ellwood ECPD & reﬂective practice Kash Qureshi How to make money as a dental technician

of the city and within a short walk of the castle and other historic landmarks and visitor attractions. To view the full conference programme please go to www.ota-uk.org We hope you are able to attend the conference and look forward to seeing you there.

Andrea Johnson, Conference Chair

For more details visit www.ota-uk.org

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6 may 2018

inconversation – tenyearsalready

■ Under a dental technical sky In the first of his new series, Derek Pearson talks about ECPD and thinks we should bake a birthday cake. Hear that ticking sound getting louder. That’s the sound of positive change coming closer and it’s all to do with the way DCPs are regulated. And Brexit.

First the changes to CPD

hat a great idea. Rather than clatter away like a rat on a treadmill, pounding out hours of CPD just to keep the numbers right, from 1 August 2018, you decide what’s best for you and put together your tailored personal development plan (PDP). Fewer CPD hours (but higher quality and more validity) is the theme. By now you know that a dental technician must complete 50 hours of valid CPD over a five-year period; make that 75 hours for CDTs. Don’t worry, I’m not going to drag you over familiar ground – the DTA will make sure you’re up to speed and no doubt you’re already making plans for the new CPD regime. And the people in Wimpole Street have even considered any CPD you have already completed. They say: ‘Depending on where you are in your cycle you will have to complete CPD based on the current and new scheme to be compliant at the end of the cycle. ‘A pro rata approach will be applied, and you will be able to find out how many hours you need to complete by using the transition tool. Once your current cycle ends, the CPD requirements for your next cycle will be based on the new scheme.’ That’s clear then. So what I want to look at here is some CPD you can get under your belt this month, during Dental Technology Showcase.

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DTS 2018 Will you manage to get to the NEC on May 18 & 19? Did you get to the Henry Schein Digital Symposium at the end of April? Both are fabulous opportunities to see the latest technology, listen to worthwhile lectures and gain that valuable CPD. Speakers at DTS have been announced and the line-up is looking exciting, but you can’t listen to everyone at the same time. You must choose the theme that best suits your PDP. Names confirmed so far include: Professor StJohn Crean, Mark Bladen, John Wibberley, Dr Finlay Sutton, Ricardo Soares and Dr Chet Trivedy. These stellar speakers bring a wealth of knowledge and credibility to the event. What follows is just a taste of what you can expect to hear. Dr Finlay Sutton is a specialist in restorative dentistry, prosthodontics, periodontics and endodontics. He said: ‘My lecture will focus on removable prosthodontics including complete dentures, partial dentures and implantsupported over-dentures. Good quality removable dentures are still a very valid alternative to implant-supported restorations. They offer many advantages such as improved aesthetics, less invasive treatment options and less complex maintenance. ‘In my lecture, I’ll cover the production process and highlight the importance of

excellent impressions to maximise retention and suction. I hope delegates will develop their understanding of how occlusion should be recorded for optimum accuracy, as well as how tooth position and adequate lip support can be established during the planning phase. ‘Ultimately, I hope to reignite delegates’ enthusiasm and love for removable prosthodontics. We can really change patients’ lives with beautifully made dentures, but only by working together can we improve outcomes and increase both professional and patient satisfaction.’

Form, function and dentures Stefan Picha, a member of the Oral Design Foundation, will discuss the importance of marrying function with form in his presentation: ‘Function is the guarantee for a long-term success. What do we have to consider in a full-arch restoration?’ He explains: ‘A lot of technicians focus on the aesthetic as the most important thing. But if the function of the restoration is wrong, then our work has failed. I believe this is an area in which technicians can grow their skills. I hope that delegates will take away from my lecture the information they need to get a better aesthetic and, more importantly, better function when they do this type of restoration.’ A chemist and director of Just Pressables, Alex Wilder will cover a session entitled: ‘How to press with success’ in the Digital & Innovation Theatre. Alex plans to speak about handling and working with dental investments for pressable ceramics. He said: ‘Despite the evolution of digital technology, pressable ceramics remains

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inconversation – tenyearsalready

DTS speakers (from left to right): Finlay Sutton, Mark Bladen, Ricardo Soares and Stefan Picha an increasingly popular field within dental laboratory technology. This is partly due to the highly aesthetic results that can be achieved, but also because using pressable ceramics is still a very costeffective way of creating a restoration.

Dentist Dr Marc Römer and MDT Andreas Leimbach will be co-presenting a session in the DTS Lecture Theatre. They will discuss ways to provide patients with discreet and highly aesthetic, removable dentures.

‘I learnt a lot about developing dental investments as well as the kinds of issues that dental technicians can encounter. I plan to speak about the misconceptions and misunderstandings regarding the use of dental investments and demystify the whole subject.’

Dr Römer explained that his concept is based on an efficient and reproducible workflow that includes CAD, 3D printing, milling and the selective laser melting (SLM) technique. Dr Römer stresses that the best results are entirely due to the craftsmanship and skills of the whole dental team.

Mark Bladen will be speaking in the DTS Lecture Theatre. His talk has been programmed in conjunction with the Dental Technicians Guild. Explaining his session entitled: ‘Aesthetics: The LiSi Effect’, he said: ‘I hope dental technicians will take away practical advice and benefit from all my knowledge and experience in using the LiSi system in my daily lab work. LiSi is a new generation of lithium disilicate high strength glass ceramic. I intend to show all the stages towards mastering the material and producing excellent aesthetics. I will explain the system and show restorations in the mouth.’ Ricardo Soares will present his lecture entitled: ‘Make it look invisible, the Signature Denture concept’. He enthused: ‘The quality of removable dentures has been raised to a level much higher than had been achieved previously, revitalising an area of dental prosthesis that was said to be dead. ‘I have seen an increased demand from patients for personalised dentures and my lecture will be an in-depth look at my concept for a signature denture.’

Andreas Leimbach adds: ‘Establishing an efficient workflow with the dentist helps the laboratory save time and money. Speaking alongside Dr Römer, we plan to show how we work together and how important it is to have a good communication between the dentist and dental technician. Good outcomes are not just about the technician’s work – they’re the result of teamwork.’

Happy birthday to The Technologist In 2006 the association became the Dental Technologists’ Association and never looked back. Things have changed a lot since the first meeting of its precursor, the Dental Technicians Education & Training Advisory Board (DTETAB), back in 1986, but the association’s principal remit is still about education and advice, something the association magazine, The Technologist, has been providing on a regular basis for some time now.

weathered the storms of the last ten years and cruised out of its first decade in pretty good shape. So, here’s an idea. At DTS, the DTA will be on stand H09 with the usual crowd of lovely people attending. Why not take cakes to the stand to celebrate?

And finally … We all need a positive spin on that confusing political juggernaut called Brexit. Well, through the grapevine I hear that once we become free of EU trade restrictions, the GDC might be better placed to regulate where dentists source their dental devices. At present a dentist can source crowns, bridges and dentures from anywhere in the world as long as they accept responsibility for their quality, and anything the GDC does to hinder such trade could be regarded as a trade barrier with legal consequences. Post Brexit the GDC could feasibly restrict such trade, insisting registered DCPs source solely from registered/regulated labs that meet their high standards and that must be good for both registered labs and patients. Fingers crossed.

Author ■ Derek is a freelance journalist and novelist. He worked on The Dental Technician and Dental Practice from 2007 to 2015 and is now editor of the online dental journal www.dentalreview.news

In fact, The Technologist reached 10 years old this year. It might look a little different, got a little bit bigger, but it the

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8 may 2018

hrfacts Aims and Objectives: Principle 7 Maintain, develop and work within your professional knowledge and skills ■ Educational aim: – to review why individuals may leave a business ■ CPD outcomes: – to consider why staff might deliberately leave a paid role – to reflect on the reasons for previous staff leaving – to consider preventing loss of essential staff

Replacing people who leave your dental laboratory is costly and disruptive to your business. Some reasons for leaving are fixable and it’s surprisingly easy to find out what might be causing avoidable turnover of staff. Richard Mander, HR consultant, looks at using exit interviews to gather useful data on why people are leaving your organisation and suggests how you might develop a strategy for improving staff retention.

■ Why did they Reasons for leaving

t’s important to understand why people leave your business. However, obtaining accurate information on reasons for leaving can be difficult. Sometimes the reasons people give for their resignations can be untrue or only partially true. Individuals may be reluctant to voice criticism of their managers, colleagues or the organisation, generally preferring to give some less contentious reason for their departure.

including questions on intentions to leave, or confidential questionnaires sent to former employees on exit or a period of time after their departure. It’s also important to consider the experiences of those still employed at the business; conducting an exit interview will gather useful data, but using information from current employees (such as employee surveys) will help pinpoint retention issues before they lead to people leaving.

Exit interviews Exit interviews can be used to ask about the reasons for leaving. Typically this consists of a short face-to-face meeting once your employee has given notice. Ideally the interviewer should not be a manager who has responsibility for the individual or who will be involved in future reference writing. Confidentiality should be assured and the purpose of the interview explained. Using an external provider to conduct exit interviews will help employers capture more accurate data about why people are leaving, as individuals are more willing to be truthful when there is reassurance of anonymity.

Improving staff retention The first steps when developing an employee retention strategy are to establish: ■ why employees are leaving and using exit interviews is a good source of data in this area ■ the impact that employee turnover has on the organisation, including the associated costs This data can be used to develop a costed retention strategy that focuses on the particular issues and causes of turnover specific to the organisation.

Useful strategies Richard Mander Richard is a freelance HR consultant with over 25 years experience in Strategic and Operational HR. He specialises in providing support to SMEs and aims to deliver cost-effective, pragmatic and practical solutions. If you would like to ﬁnd out more about this topic, or advice on other HR matters, you can contact him at www.manderhr.com 07715 326 568.

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Use of surveys Alternative approaches to collecting exit data involve the use of confidential attitude surveys for current employees,

As well as basic pay and benefits, organisations should consider the following elements, all of which have been shown to play a positive role in

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leave? improving retention and are likely to impact the working environment: ■ Job previews – Give prospective employees a realistic job preview at the recruitment stage. Don’t oversell the job or minimise aspects of the role. ■ Career development and progression – Maximise opportunities for employees to develop skills and move on in their careers. Understand and manage people’s career expectations. Where promotions are not feasible, look for sideways moves that vary experience and make the work more interesting. ■ Consult employees – Ensure that employees have a ‘voice’ through regular appraisals, attitude surveys and grievance systems. Where there is no opportunity to voice dissatisfaction and influence outcomes, resigning may be the only option. ■ Be flexible – Wherever possible, accommodate individual preferences on working hours and times. As part of this, it’s also important to monitor workload and ensure it is manageable within working hours. ■ Avoid a culture of ‘presenteeism’ – Where people feel obliged to work longer hours than are necessary to impress the ‘boss’. ■ Treat people fairly – A perception of unfairness, whatever the management view of the issue, is a major cause of voluntary resignations. For example, perceived unfairness in the distribution of rewards is very likely to lead to resignations. ■ Visit DTA’s website for an example exit interview document and for recommended further reading on family-friendly employment.

CPD

ethiclegal & al is sues

CPD Legal and ethical issues – 30 minutes To complete your CPD, store your records and print a certiﬁcate, please visit www.dta-uk.org and log in using your member details.

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Q1 Exit interviews are held in order to: A Understand your clients’ needs B Get a better understanding of why employees leave C Guard against the risks of future litigation D Understand your suppliers better Q2 Exit interviews should ideally be conducted by: A The person’s line manager B The person responsible for providing references C An independent person D The CEO or business owner Q3 Surveys can help to improve the accuracy of exit data as: A They are more likely to be seen as conﬁdential B They can be incentivised C They can be managed online D They can cover more areas Q4 Employees can be given a ‘voice’ through: A Reward systems B Pay and beneﬁts C Company newsletters D Appraisals, surveys and grievance systems Q5 A major cause of voluntary resignations is: A A perception of unfairness B The business location C The company HR policies D The company business strategy

DENTAL LABORATORY BENCH SPACES TO RENT LONDON NW1 Bench space to rent in a newly refurbished very spacious and bright dental lab, including full use of all new equipment. Great location, 5 mins walking distance to Harley Street and several tube stations (including Euston main line) and 10 mins to the West End. £750 pcm Please call Josh on: 07773 874 476 the

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10 may 2018

employerresponsibilities

■ What are your responsibilities By Peter Blake You may already have some employees or you may be thinking about taking on someone to help with the growth of your business. In this article we outline some of the main responsibilities that you have as an employer.

Contractual arrangement

t is always advisable to put the terms of the employment into a proper contract of employment. This can help avoid any misunderstandings further down the line. The main points to be covered would be rate of pay, working hours, holiday entitlement, grounds for dismissal, and so on.

Rates of pay Every employee has the right to be paid at least the National Minimum Wage. The current minimum wage rates will be changing with effect from 1 April 2018 to: ■ ■ ■ ■

Age Age Age Age

16–17 – £4.20 per hour 18–20 – £5.90 per hour 21–24 – £7.38 per hour 25+ – £7.83 per hour

Discipline and grievance procedures

Aims and Objectives: Principle 7 Maintain, develop and work within your professional knowledge and skills ■ Educational aim: – to consider some of the basics around employing someone ■ CPD outcomes: – to indicate some of the main points to consider when taking on an employee – to suggest some of the factors that SME employers should consider – to encourage managers to seek current and relevant advice

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Your company rules need to cover things like absence, health and safety, timekeeping and performance standards. If rules are broken, you need to have clear written procedures to carry out the review and reporting of these rule breaks and outline what happens next. The employee must have the chance to raise their concerns through the written grievance procedures as well. You must have a good reason to dismiss someone from their employment and show that you have been fair in the review procedure. This would include: 1. informing the employee of the problem you have with their performance or conduct 2. holding a meeting to discuss the problem 3. allowing the employee to be accompanied if requested 4. deciding on an appropriate action 5. allowing the employee the right to appeal

An employee is entitled to one week’s notice of dismissal, rising to two weeks after two full years of employment. This notice period continues to rise by one week for each further full year of employment up to a maximum of 12 weeks.

Holiday entitlement Employees are entitled to holidays from the first day of employment. There is an excellent tool to calculate holiday entitlement to be found at: ■ www.gov.uk/calculate-your-holiday -entitlement.

Maternity pay Statutory maternity pay for eligible employees can be paid for up to 39 weeks. There is an excellent SMP calculator to be found at: ■ www.gov.uk/maternity-paternity -calculator

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as an employer? A similar calculator is now available to calculate paternity pay as well.

Payment Submission and/or Employer Payment Summary and make some year end declarations. This then eliminates the need for the old P35 and P14 forms. All reporting to HMRC is now done online in real time.

Year end responsibilities The end of the tax year on 5 April brings with it some reporting requirements for the employer. 1. Report to HMRC on the year just ended and supply a form P60 to each of your employees. This P60 must be given to them by 31 May. At the end of the tax year, you or your payroll provider must submit a final Full

2. If your employees receive any expenses or benefits, then this must be reported to HMRC by 6 July via a form P11D and any class 1a national insurance due to them must be paid by 19 July.

Throughout the year you are required to report each payment of wage or salary to HMRC in real time as it is paid. When you have a small number of employees then you may feel comfortable doing it yourself, but if you start to grow then you might want to consider using your accountant or a payroll bureau to take on this task on your behalf!

Auto enrolment pensions CPD Legal and ethical issues – 30 minutes To complete your CPD, store your records and print a certiﬁcate, please visit www.dta-uk.org and log in using your member details. Q1 The national minimum wage rate for an 18–20 year old from 1 April 2018 is: A £4.20 per hour B £5.90 per hour C £7.38 per hour D £7.83 per hour

We covered the responsibilities of employers regarding providing workplace pensions in the last edition, so please refer back to that if you are unsure what is required. Employing someone is a big commitment and brings with it many responsibilities. Please ensure you speak to your own advisors before taking this big step to make sure that you are ready to comply.

Q2 One of the year end payroll forms that need to be completed is: A P60 B P45 C P50 D P10 Q3 The year end P11d must be sent to HMRC by: A 5 April B 30 April C 31 May D 6 July

Peter Blake Peter is a chartered accountant, business coach and master practitioner of NLP. He has his own practice based in Wiltshire, lectures on ﬁnance and mentors new business start-ups for Gloucestershire Enterprise Ltd.

Q4 The P60 must be given to the employee by: A 5 April B 30 April C 31 May D 19 July Q5 An employee is entitled to how much notice of dismissal in the first 2 years? A One week B Two weeks C Four weeks D Twelve weeks

For further details, contact Peter on 07912 343 265 or email peterblake@pbcoachingandtraining.com

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12 may 2018

finance

■ Making tax digital By Tony Bowden Bluewave Business Solutions In 2015 the UK government announced its ambition to become one of the most digitally advanced tax administrations in the world. In order to achieve this, the government is introducing us to Making Tax Digital (MTD).

he driver behind the announcement is to help individuals and businesses get their taxes right, to keep on top of their financial affairs, and of course to help HMRC collect taxes that are due in the most efficient way possible. Currently over £8 billion a year in tax is lost from avoidable taxpayer errors. MTD will mean that the taxpayer will no longer have to wait until after the year end to find out how much tax is due. Under the policy, businesses, landlords and selfemployed individuals would have to update HMRC once every three months on their main, or in some cases their second, source of income. With all income and tax data being in one place, each business or individual would be provided with a complete picture of their income and tax position throughout the financial year. Since the announcement in 2015, work has been going on behind the scenes in preparation for the conversion, and HMRC introduced the first pilot scheme in April 2017 with a wider, live pilot due to begin shortly in the spring of 2018.

Aims and Objectives: Principle 7 Maintain, develop and work within your professional knowledge and skills ■ Educational aim: – to be aware of the changes for tax submissions by MDT ■ CPD outcome: – to encourage individuals to consider how the future digital changes to the UK tax system will likely affect individuals and businesses

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MTD is being phased in over a number of years and for different taxes. Whether you’re a company, self-employed, charity, landlord or LLP, from April 2019 businesses that are above the VAT threshold (those with a turnover over £85k for the 2017/18 tax year) will be mandated to keep records digitally using MTD compliant software. This means that if you currently maintain hand-written records, or spreadsheets (in isolation, with no third party software integration) to prepare your VAT returns, you’ll need to utilise dedicated software that is MTD compliant. The portal provided by HMRC that you might use to submit VAT returns currently will no longer be available to you. Any business that is not VAT registered or is below the threshold will not be required to sign up at this point, but they are able to do so voluntarily if they wish. However, those in employment who have a second

income deemed self-employment or property, that combined is over £10k pa, will be included. HMRC has made a commitment to ensure that businesses under the VAT threshold will not be within the scope of MTD until at least April 2020 to ensure a robust and workable system is in place before a wider scale rollout. From April 2020, it’s likely there will be a wider rollout to include all other taxes, including income tax and corporation tax. Progress is still being made with consultations and testing systems and the dates may change. All businesses, whether they’re required to report using MTD compliant software by April 2019, or later the following year, are being advised to act now and prepare for the change. ■ For further reading visit www.gov.uk and search for ‘Making tax digital’.

CPD Legal and ethical issues – 30 minutes To complete your CPD, store your records and print a certiﬁcate, please visit www.dta-uk.org and log in using your member details. Q1 How often will you have to update HMRC with your financial details under MTD? A Every year B Every six months C Every month D Every quarter Q2 When is the live pilot for MTD due to start? A It has already started B Spring 2018 C April 2019 D April 2020 Q3 What type of businesses will be mandated to provide data under MTD from April 2019? A All businesses B VAT registered businesses C Limited companies D Sole traders Q4 What is the current VAT threshold? A There isn’t one B £100,000 C £85,000 D £200,000 Q5 When should those impacted by MTD start to make plans to become compliant? A April 2018 B April 2019 C Immediately D Not until 2020

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consent

■ Can we fix it? Consent considerations for denture repairs by Kevin Lewis Aims and Objectives: Principle 3 Obtain valid consent ■ Educational aim: – to be aware of the duty of care requirements when providing advice to patients ■ CPD outcomes: – to gain an understanding of valid consent relating to denture repairs – to be aware of the need to inform patients to allow them to decide whether to accept the risks and limitations of treatment

The theme song for the children’s TV programme Bob the Builder became the unlikely ‘Christmas No. 1’ in December 2000. The lyrics don’t confirm how much Bob would have charged for his building services over the Christmas period, but these are separate questions anyway. I will cover the financial and contractual aspects of providing dental services in a later article. At first sight, a patient who arrives with a broken denture asks an equally simple question – ‘Can you fix it?’ And in most cases the simple answer is, ‘Yes, we can’. But, just as with Bob the Builder, it’s actually a bit more complicated than that.

Legal and ethical principles

healthcare professional owes a duty of care to any patient in whose treatment they become involved, and put simply, this means that the healthcare professional must exercise a reasonable standard of care and skill in terms of the decisions they make, the advice they give and the treatment they provide. That is what the law expects of us and also what our professional regulator, the General Dental Council (GDC), expects of us in terms of our ethics and professional conduct. All dental registrants should be familiar with the GDC’s published guidance.¹

The eight key points to consider in this definition are: a) voluntary – a free choice made in the absence of any kind of undue influence b) continuing – a consent given for each occasion when treatment is proposed c) particular – a specific consent for a clearly specified procedure, to be carried out by a specific person on a specific occasion d) purpose (why is it needed?) and nature (what does it involve?)

Author, Kevin Lewis Consent in healthcare has usefully been defined as follows: ‘The voluntary and continuing permission of the patient to receive a particular treatment. It must be based upon adequate knowledge of the purpose, nature and likely effects and risks of that treatment including the likelihood of its success and any alternatives.’ the

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consent e) likely effects (what can I expect/how will I feel if things go to plan?) f) potential risks (what could go wrong? what else might happen and how might this affect me?) g) likelihood of success (how likely is this to work? and what would qualify as ‘success’?) h) alternatives (what if we did nothing at all, or something different?) It is part of our duty of care to obtain a valid consent from the patient before providing any treatment. A failure to do so is a breach of that duty and it can form the basis of a claim in negligence and/or a complaint to bodies such as the GDC. In many healthcare interactions, the patient starts at a disadvantage because they have a lot less technical knowledge and understanding than the healthcare provider. To bridge that gap, and put the patient into a position where they can make a considered and properly informed decision as to what treatment to agree to, when, and from whom, we need to explain (a)–(h) above in terms that make sense to them. Each patient is different, and our aim should not be to simply pass on facts and information, but to help them to understand how this information relates to their personal situation at the relevant time. There are issues of mental capacity to take account of but space does not permit us to explore those here. A denture repair seems a simple enough concept for a patient to understand – much easier than explaining a complex medical or dental procedure on a part of the body that the patient knows little about and can’t see. But therein lies the danger. For example, is the appliance being repaired for the first time or has it broken before? Under what circumstances did it break? If repaired previously, is this a new/different problem or has the previous repair failed? How old is the denture, and how vulnerable to breakage, and has anything changed in the patient’s mouth that might have caused or contributed to the present problem? the

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(Have any teeth been extracted or any restorations been lost, placed or replaced? Has a retained root appeared on an otherwise edentulous ridge? Has pain or discomfort led the patient to adopt a modified occlusion, creating forces that the denture was not designed to withstand?) Without knowing the answers to these and other questions, one can’t really cover points (d)(e)(f)(g) or (h) in the consent checklist above. If you don’t understand the risks yourself, you are not in a great position to help the patient to understand them. When the consent process goes wrong, it opens the door for the patient to say afterwards, ‘I would never have agreed to have this done, if you had only told me ...’ This becomes even more likely if a denture repair fails again prematurely and causes the patient embarrassment, inconvenience, etc., and if the timing has other, wider consequences like ruining a special occasion, then the patient’s frustration and displeasure often shifts from the broken denture itself towards the person whom they had paid to repair it. If you are wondering from the start whether attempting a denture repair makes sense at all, or perhaps doubting how long the repair is likely to last, you need to explain these concerns to the patient. Give them the facts, help them to understand the risks, and leave them to choose whether or not to accept those risks – and the consequences.

Documentation Patients cannot be expected to realise the relevance of some of the above questions to the fact that their denture has broken (or keeps breaking), so it is our job to help them to understand. And, in doing so, we can protect ourselves against the allegation that the patient’s consent was invalid because they were denied full knowledge and understanding of the facts and risks when they agreed to proceed. In this connection, it is important to document the consent process in order to be able to demonstrate that you did provide all the relevant information and

also did your best to ensure that the patient understood what they were agreeing to (and any associated risks and limitations). Giving the patient a written information sheet can be very helpful, but then your records should be sufficient to confirm that this happened before seeking the patient’s consent, the patient had a chance to read the information and ask any questions and, crucially, because of a major UK Supreme Court decision in 2015² – that you tailored this information, warnings and advice to the

Kevin Lewis, BDS (Lond) LDSRCS (Eng) FDSRCS (Eng) FFGDP (UK) Kevin graduated in London in 1971. He spent 20 years in full-time general dental practice and 10 further years practising part time. He became involved in the medico-legal ﬁeld in 1989, ﬁrstly as a member of the Board of Directors of Dental Protection Limited (part of the Medical Protection Society group of companies). He became a dento-legal adviser in 1992 and from 1998 was the Dental Director of Dental Protection for 18 years and also an executive member of the Council (Board of Directors) and executive management team of the Medical Protection Society, roles from which he stepped down in 2016. He is a Trustee and member of the Transition Board of Directors for the proposed College of General Dentistry. Kevin has been writing a regular column in the UK dental press since 1981 – originally as the Associate Editor of Dental Practice and since 2006 as the Consultant Editor of Dentistry magazine. He still writes and lectures regularly all over the world, and has been awarded honorary membership of the British, Irish and New Zealand Dental Associations.

may 2018 15

consent specific patient and their individual circumstances. It is no longer enough to adopt a ‘one size fits all’ approach to information and warnings given to patients as part of a consent process. And, finally, getting the patient to sign a

consent form will not always protect the healthcare provider as much as many seem to believe. The validity of the consent is determined by the quality and relevance of the information provided, and whether or not the patient really understands that information and what it

means for them personally. Sometimes a sufficiently detailed clinical record is worth more than a signature on a consent form. 1 Standards for the Dental Team. General Dental Council www.gdc-uk.org. 2 Montgomery v Lanarkshire Health Board [2015] UKSC 11.

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ethic Q4 To what extent are we required al to warn the patient about the To complete your CPD, store your records and print a certificate, risks and limitations of different please visit www.dta-uk.org and log in using your member details. ways of repairing their denture? 60 m Which one of these statements is inut es Q1 All but one of the following are component parts of our correct? overall duty of care to a patient who is asking if we can A The patient already knows that repair their denture. Which one is the exception? dentures can break, so we don’t need A The advice we give them to state the obvious B The care and attention we exercise/demonstrate in our B We only need to tell them about the things that might go assessment of the options wrong if we make a mistake when carrying out the repair C The technical quality of any work we carry out C We need to tell them as much as they need to know to D Ensuring that the fees we charge are reasonable for what help them understand the risks, so that we put the patient we do in a position where they can decide whether or not they want to accept the risks and limitations Q2 What level of skill, care and attention is required in order D Once we have decided how we plan to repair the denture, for us to have satisfied our duty of care to a patient? it is best to keep quiet about the risks and focus on the (Indicate the correct answer.) benefits – or we might talk the patient out of it and lose A The highest possible standard the business B A standard that is in keeping with how much or how little money they are paying us Q5 Arising from treatment provided in Scotland, a landmark C A level of skill and care that would be considered legal case involving consent in healthcare resulted in a reasonable and proper by a responsible body of Supreme Court decision in 2015 that is binding across the competent professionals working in the same field whole of healthcare and the whole of the UK. What is that D The standard that the individual patient demands of us, very important case called? however high or low A Moriarty v Lanarkshire Health Board B Montgomery v Lanarkshire Health Board Q3 One of the requirements of a valid consent is that it is given C Matrimony v Lanarkshire Health Board voluntarily. In relation to this requirement, all but one of the D Mullarkey v Lanarkshire Health Board statements below are correct. Which one is not correct? A The patient must be given a completely free choice to Q6 As a result of the legal case referred to at Q5 above, a agree to, or decline the treatment patient’s consent is only valid if: B It is quite OK to talk the patient into proceeding in the way A You have warned the patient of any very serious or we would prefer common risks of the procedure C The patient’s decision must not be influenced by having B You have given the patient the standard information and been given incorrect information about the work to be warnings of any risks that most reasonable patients would carried out and the risks/benefits/ likelihood of success want to be told about D We must not take advantage of the fact that we probably C You have tailored your explanations and warnings of any have a lot more technical knowledge than the patient material risks involved to the specific patient and their particular individual circumstances D You have asked the patient what risks they would like to be warned about Consent for denture repairs: Legal & ethical CPD – 60 minutes

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Q7 The General Dental Council publishes guidance on the standards of ethics and professional conduct that they – and patients – expect. What is the current guidance document called? (Indicate the correct title of the document.) A Standards for Dental Professionals B Standards for the Dental Team C Maintaining Standards D Keeping out of trouble – required standards in dentistry

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If a patient is given an information sheet, it is 60 m important to record this inut fact in the clinical notes, es ideally conﬁrming when the information was provided D Patients should be given a chance to read and consider the information provided before being asked for their consent

Q8 Only one of the following statements is true. Which one? Q10 Only one of these statements is true. Which one is it? A Consent forms provide absolute protection against legal A A patient who agrees to the cost of a denture repair has challenge regarding consent also consented to the repair itself B If the patient conﬁrms in writing that they have received all B Consenting to a denture being repaired is not the same as relevant information about what is proposed, they can’t agreeing the price argue afterwards that they needed additional information C There are no circumstances in which you can charge C A signed consent form listing the information that has someone for repairing their denture if you have charged been given to the patient shows that they must have them to repair the same denture in the previous 12 understood this information months D A full and detailed record of the discussions with the D The initial provision of a denture is regulated by and patient before seeking their consent is often more valuable potentially subject to investigation by the GDC – but a than a signed consent form denture repair is not. Q9 Patient information sheets can provide valuable support for the consent process. Which one of the following statements is not correct? A If patients don’t understand the information provided to them, it is their responsibility to say so and ask questions. If they don’t, it is not our problem B Patient information sheets are especially helpful for patients who prefer written information rather than having to absorb and remember what they are told verbally

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cad/cam

■ It fits too well

The modern problems with CAD/CAM technology and resin bonded bridgework – A case study

Aims and Objectives: Principle 7 Maintain, develop and work within your professional knowledge and skills ■ Educational aims: – to highlight the use of CAD/CAM technology within the dental profession – to inform the reader of potential aesthetic issues within too good a fit for a resin bonded bridgework ■ CPD outcomes: – to highlight how CAD/CAM technology has developed within the dental workforce and issues that may arise during fabrication – to highlight satisfactory film thickness of luting agents for longevity and aesthetics for restorations

by Alaa Daud, BDS MFDS RCS (Edin) MDTFEd; Ken Snell, RDT and Claire Forbes-Haley, BDS MJDF RCS (Eng) FDS RCS (Eng)

Abstract Dentistry is currently undergoing a digital revolution. Computer aided design/computer aided manufacturing (CAD/CAM) has been introduced for the construction of crowns and bridges as an alternative to the lost wax technique. The precision of CAD/CAM to produce a restoration with a predetermined internal space is crucial to allow enough room for the luting agent. Recently, luting agents have been developing rapidly, aiming to achieve minimal film thickness while possessing the low solubility and high strength necessary for long-term retention and longevity of the restoration. The aim of this article is to describe a CAD/CAM constructed resin retained bridge that fits too well, highlighting the reason for it failing to achieve its aesthetic goal.

Introduction

n the last 20 years, dental technology along with medical and information technology has changed the way we interact with computers in all industries. In the past there was only one way to make indirect dental restorations, getting on some gloves (maybe not always 20 years ago!) and getting a patient covered in impression material. This has now changed. You can get the information from the mouth via a scan, send the information and receive your restoration. There are multiple combinations of information acquisition available. The common methods for producing indirect restorations still regularly involve classical impressions, as intraoral scanners are expensive commodities. After impressions or scanning, conventional laboratory fabrication or dental CAD/CAM (computer aided design, computer aided manufacturing) is used, as shown in Figure 1 (overleaf). The conventional laboratory process Following the preparation of the

abutment/s, a silicon impression is obtained. A stone model is prepared at the laboratory as a replica. Wax patterns are then manually fabricated for metallic restorations, followed by the precision casting and porcelain veneering if required. The conventional powder buildup firing process of porcelain is still technically sensitive.

The dental CAD/CAM process With the fourth generation CAD/CAMs available, the prepared abutment is scanned by an intraoral digitiser to obtain an optical impression. This image is recognised on the monitor and transferred to a 3-D graph using CAD software. Finally, the restoration is processed by a computer assisted milling machine (CAM). When considering the difference in the steps above, one can conclude that conventional methods of laboratoryfabricated prostheses are labour-intensive and require high skill and precision. Using CAD/CAM it seems can save time and the

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cad/cam Intraoral abutment preparation

Silicone impression

Stone model

Intraoral digitizing (optical impression)

CAD Virtual wax up

CAD Machining Centre

oxide high performance ceramics. Examples of the oxide high performance ceramics offered as blocks for CAD/CAM technology are aluminium oxide and zirconium oxide, with the latter having high flexural strength and fracture toughness compared with other dental ceramics, increasing the longevity of these restorations.6 ■ Resin materials, either to be used for the lost wax technique, or for longterm temporary restorations.

Wax up

CAM

Laboratory

Chair Side

restoration

Along with increased adoption of technology, patients are demanding more conservative management of their teeth and tooth replacement. This has led to the adoption of dental implants and resin based technologies to replace teeth without a removable prosthesis.

Resin retained bridges (RRBs) Luting to abutment preparation Fig.1: resources, again as long as you are computer savvy, as CAD/CAM technology can compensate for changes in dimension (possible shrinkage) that come with processing. CAD/CAM can allow for easier quality control checks by designing optimal shapes, which can be replicated based on material characteristics and thereby preventing degradations such as residual strain because of processing.1 Another perk of digitising information is that optical impressions, processing data and final production plans can be saved to enable retrievability of information and quality monitoring of prosthetic devices constructed via CAD/CAM technology.

CAD/CAM systems have evolved over the last decade and are now also used for the manufacturing of implant-supported prostheses, such as customised implant abutments3 and diagnostic templates for implants.4

Materials used for CAD/CAM processing In the early 1980s, nickel-chromium alloys were used as an alternative to gold alloys due to the increase in gold prices at that time. However, nickel allergies became a problem and a transition to allergy-free titanium was introduced.5 Currently, the following materials are available for CAD/CAM processing:

CAD/CAM In the early 1970s, Francois Duret pioneered the dental CAD/CAM in restorative dentistry.2 These systems have been used for the fabrication of fixed prosthetic restorations such as crowns, bridges, inlays, onlays and veneers.

■ Metals, such as titanium, titanium alloys and chrome cobalt, have been processed using dental CAD/CAM milling devices. ■ Ceramics, such as silica-based ceramics, infiltration ceramics and

RRBs were first developed as a conservative fixed prosthesis to replace missing anterior teeth. In 1973, Rochette described a perforated cast retainer that was considered a temporary restoration with two years of service.7 Later, several studies concluded that unperforated retainers perform better than perforated ones.8-10 Since then, however, there have been significant changes in materials used, design, tooth preparation and methods of construction of RRB’s framework. Metal-free restorative alternatives are currently available, including fibre-reinforced composite resin and all-ceramic materials. These metalfree bridges are superior in aesthetics but metal ceramics have the following advantages11: ■ ■ ■ ■ ■

Long-term clinical data available Most minimally invasive Relatively lower cost Simple rebonding Reduced connector fracture and better longevity of restoration

Poor results have been reported in studies where high gold alloys were used

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CELEBRATING

2008

2018

YEARS DTA in support of you The Technologist was launched in the spring of 2008 to coincide with the GDC’s introduction of mandatory CPD for newly registered dental professionals. Producing a 28-page publication, originally quarterly and then bi-monthly – was a challenge. DTA had never done anything like this before! But the introduction of professional registration was a big thing for you – our members – and we wanted to do what we could to support you.

The purpose of TT was primarily to ensure that your verifiable CPD needs were covered. If you weren’t able to do any other training, you (and we) could rest assured that you would still fulfil the GDC’s CPD requirements. Thank you to all our authors and contributors over the 10 years. We could not have done it without you. We think, together, we all did OK: our strategy of support was successful.

By Numbers

187

Hours of CPD

Editions of The Technologist

3 Number of CPD supplements

2008

The Technologist was launched

2018 birthday supplement Messages of congratulations

“

It gives me great pleasure to send my congratulations to the DTA and The Technologist on its tenth birthday. We are proud to have published The Technologist from the beginning and are delighted to continue to be involved in its development. It is an appropriate time to thank all those involved: Sue, Vikki, Dennis (design) and Dennis (print and despatch) for their professional work and to wish The Technologist many more years of bringing valued information and education to its readers.

“

”

James Green DTA President 2016–2018

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”

Stephen Hancocks TT Publisher 2008–2018

“

The launch of The Technologist journal by the DTA, 10 years ago, has been a valuable source of news, information and interesting CPD articles that have continued to enhance the knowledge and understanding of all dental laboratory techniques, materials and dental laboratory management, for all disciplines of dental technicians.

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“

The consistent high quality of the articles published in The Technologist from authors and contributors has been outstanding, while enabling UK dental technicians to gain and maintain a high level of CPD through membership of the Dental Technologists Association.

”

Mike McGlynn DTA President 2014–2016

The Technologist soon became a leading journal for dental technicians when it was launched in 2008. Congratulations on your tenth birthday and thank you for keeping our members informed and up to date for the last decade. Here’s to the next ten years!

“

Congratulations to DTA and the team who produce The Technologist which keeps technologists not only up to date with their statutory responsibilities but also informed of new techniques and procedures which are so necessary to improve standards for me and my laboratory. Thank you for your help and entertainment over the past 10 years and I wish you well for the future. Brian Gordon DTETAB Chairman 1994–1996

“

The Technologist has come a long way over the past 10 years. The first issue in summer 2008, with its theme ‘Now is the Time’, coincided with the end of the transition period for statutory registration. Now, in summer 2018, we see the start of the implementation of eCPD. The Technologist continues to provide news, views, legislation updates and articles to help us to maintain your professional development in many forms of media; long may it continue to do so.

”

John Stacey DTA President 2010–2012 the

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“

The fact is The Technologist (TT) is such a remarkable publication because it is the window through which UK dental technologists (DTs) and clinical dental technologists (CDTs) see their professional world. It is a pleasure to congratulate the past and current members of the editorial team on their 10 years of achievement and growing importance of TT to the community of professionals that it serves. For all registered DTs & CDTs who are members of the Dental Technologists Association (DTA), the provision of their regular technical updating, digital development support, SME business information, etc., and quality assured verifiable CPD through The Technologist provides essential and individual help for every DTA member. Let’s now plan for the future, such that the DTA may provide for ongoing education and lifelong learning to support the membership over the next ten years and beyond.

”

Tony Griffin MBE DTETAB Chairman 1998–2002 DTA President 2002–2004 & 2005–2007

2018 birthday supplement Memory lane

The Team DTA would like to say a big thank you to the team behind the publication, in particular to Editor Vikki Harper, who has developed the journal over the past 10

Vikki Harper, Editor 2008–present

years. Various members of the DTA management team have supported Vikki over the time. The current editorial team comprises Tony Griffin and James Green.

Tony Griffin, James Green, Editorial Panel 2008–present Editorial Panel 2014–present the

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A decade of dedication and ten years of your thanks

“

The Technologist is a superb journal. Better than expected. I’m very pleased; thank you! More of the same please with an eye on core CPD subjects and product information. CPD in medical emergencies and legal and ethical issues would help.

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”

September 2009 issue was very interesting and informative for myself and others in prosthetic-based dental labs. We have asked for this for a while and you have listened and delivered. Many thanks.

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I find it useful to have the TT magazine, as I am a working mum and find it difficult to attend courses to gain CPD, so to be able to do it from home is beneficial.

”

Angela by email Originally published in the April 2011 issue

“

I have nearly completed my CPD for this cycle – it may not have been so easy without the DTA’s convenient source. Good service.

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C Parfitt Originally published in the October 2012 issue

Join in the celebrations Complete the word search to win a bottle of bubbly Can you find the nine words listed below in the grid? ■ Resin

■ Sterilisation

■ Alumina

■ Oesophagus

■ Caries

■ Deciduous

■ Maxillary

■ Occlusion

■ Alveolar Words may run diagonally, up, down and across, and the same grid letter may appear in more than one word. One reader, who locates the nine words, and emails the completed grid to sueadams@dta-uk.org by July 1, 2018, along with their name, address and member details will win a bottle of Champagne.

A message just to say thank you for the excellent CPD you have given me over my CPD cycle, and for the times I have had to phone you. Glad to be part of such a great association and look forward to my next CPD cycle, this time with a great deal more calm, thanks to the help of the DTA.

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Teerathraj, London Originally published in the February 2010 issue

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Nigel, West Glamorgan Originally published in the November 2009 issue

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David, Helston Originally published in the Autumn 2008 issue

“

There are no better ways of obtaining CPD. Once I open The Technologist, it makes me read and read again because of the amount of knowledge and skills it provides. I am sure it is very beneficial for old and new technicians – including students.

Patrick by email Originally published in the August 2013 issue

“

I cannot be the only person worrying about doing things right with the new ECPD coming into effect so I am happy that you are all on board to help. I just wanted to say thank you.

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SJ Roots Originally published in the February 2018 issue

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cad/cam Table 1: Common reasons for failure of metal-framed resin retained bridges

Debond

One or more of the adhesive retainers became detached

Delamination or porcelain fracture

Ceramic-metal bond failure or fracture of a unit which necessitates a repair or remaking of the prosthesis

Caries

Requiring treatment under or immediately adjacent to a retainer

Fractured metal framework

Structural failure of the metal framework leading to implications for the survival of the restoration

Others

Periodontal loss of an abutment Patient’s request – poor aesthetics Development of a pontic residual ridge discrepancy

in the construction of RRB retainers.12 Nickel-chromium alloys were used almost exclusively because of their rigidity in thin section, and also the bond with resin was reliable. A study testing bond strengths of maxillary anterior base metal resin bonded retainers with different thicknesses found that the dislodging forces for the canine morphotype appeared to progress linearly with increasing thickness, and that a retainer of less than 0.7 mm thickness on a canine has been shown to have less resistance to dislodgement.13

Case study

Many factors affect the success of RRBs, including general factors such as patient age, health and expectation, and local factors related to dental health, RRB design, retainer coverage, luting resin and opposing dentition. Reasons for failure of a metal-framed RRB are described in Table 1.

■ ■ ■ ■

Table 1: Common reasons for failure of metal-framed resin retained bridges Debonding has been described to be the most common problem for metal-framed restorations (92.6% of all failures).10 A study evaluating different fracture sites showed that 57% of the dislodgements were due to failure at the resin/retainer interface14; therefore, it is crucial to ensure perfect adaptation of the retainer to the abutment tooth. The following case describes the fit of a CAD/CAM constructed resin retained bridge that fits too well, highlighting the reason for it failing to achieve its aesthetic goal.

A 17-year-old male, JB presented at the orthodontics department for restorative options to replace his congenitally missing upper lateral incisors. The patient was fit and well and all extra-oral and intra-oral tissues healthy. A combined orthodontic/ restorative assessment was conducted to examine the occlusion, positioning of facial support, tooth, gingival and smile line. Treatment options available, considering level of destructiveness were: removable partial prosthesis resin retained bridges conventional cantilever bridges dental implant crowns/bridge

Treatment plan The final agreed restoration was a double abutted resin retained bridge supported by UR1 UL1 to replace UR2 UL2 as one whole unit. This design allows for retention of the UR1 UL1 following orthodontics and takes into consideration the de-rotation and movement of the UR13 UL13 and their chance of relapse (Image 1). No preparation of the teeth is required. After discussing a diagnostic wax-up with the patient, and agreeing the correct shade, a silicon impression was taken and sent to the laboratory. This impression was cast and the technician established an optical impression of the model. The digital model can be used with CAD/CAM to fabricate the metal framework. Aiming

for the best possible fit, the software automatically attempts to achieve the closest fit (Image 2 – overleaf). On the cementation appointment, the bridge was tried-in to confirm the accurate fit. Panavia™F opaque (Kurary, America, NY) was used, a version of the Panavia™ family, dual cured, fluoride releasing aesthetic universal resin based cement. The patient was happy on leaving the surgery. The patient returned two weeks later as he had noticed that the front teeth appeared greyer than the surrounding dentition. It appeared that the metal of the bridge was showing through as a grey discolouration on the incisal edges of the central incisors (Image 3 – overleaf). Since the invention of opaque Panavia™, we no longer had any issues with metal shine through using this style of restoration. Therefore, we investigated what the differences were in this case causing metal to shine through. The patient did have a higher level of translucency on the incisal edges of UR1 and UL1 with deep palatal cingulum. This means these teeth could more easily show decolouration, but again following normal protocol using opaque cement, this would not usually be an issue. As the frame was constructed using CAD/CAM software (Renishaw DS20 White light scanner), we could recall all

Image 1: Metal framework for resin retained bridge the

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cad/cam conditions.15 The closer the framework of the retainer and the margins to the abutment tooth structure, the smaller the gap and thickness of the exposed luting cement layer. Nevertheless, a large space favours cement degradation, which could be described by dissolution, mechanical wear and erosion.16 Jacobs and Windeler found no significant difference in the rate of cement dissolution for gaps ranging between 25 and 75 µm, whereas a gap size of around 150 µm demonstrated a statistically significant increased rate.17 On the other hand, a framework that fits too well with no space for the cement, will also lead to debonding and failure of the restoration.

Image 2: CAD/CAM screen shot of the resin retained bridge the settings and specification of the framework. On closer investigation the perfect fit that the CAD/CAM allowed for was ‘0 µm’ space between the retainer and the abutment teeth in order to achieve the perfect fit. However, this automatic setting was not what the dentist prescription or a technician would see as a perfect fit because it was not allowing any space for cement. This space for cement normally occurs naturally due to small errors is manufacturing by hand. Therefore, due to the accuracy of CAD/CAM, there was insufficient space for cement. This meant that even with opaque cement, the film of cement was too thin, allowing the metal retainer to show through the translucent incisal edges. Despite the retainers having a ‘perfect’ fit, luting agents must maintain a minimal film thickness necessary for longterm retention of the restoration and sufficient opacity. Therefore, the setting the

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on the CAD/CAM software was intentionally changed to accommodate enough space for the luting agents. A new RRB was constructed via CAD/CAM with a space of ‘30 µm’ between the tooth and retainer to allow enough thickness for the cement. The new RRB was cemented using the same cement. A difference was noted aesthetically as no metal was showing through the incisal edges of the central incisors (Image 4).

Discussion Location and fit of any metal framework has a high clinical relevance and is important to biological and mechanical restorative failure. The so-called ‘clinically acceptable’ marginal fit has varied in the literature, with previous investigators considering the marginal discrepancy of less than 50 µm to be acceptable and is difficult to detect under clinical

The film thickness of a luting material is influenced by several factors, including the size and shape of the filler particles, the substrate that the material will bond to, the viscosity of the mixed unset material and its setting time. In the past, composite resin cements have demonstrated a greater film thickness than other types of cements.18 They set rapidly before they can flow to achieve their minimal film thickness goal. Resin based cements with high filler content will possess lower shrinkage on polymerisation and improved physical properties will increase the viscosity and diminish the flow. Recent composite resin cements have improved their physical properties, aiming to achieve higher bond strengths, lower polymerisation shrinkage, and the improved colour stability Panavia™F cement used in this case has a recommended film thickness of 12 µm, which achieves a balance between optimal physical properties and minimal film thickness. During the virtual 3-dimensional (3D) design of any restoration, CAD/CAM system settings allow the adjustment of different parameters, such as the cement space and restoration thickness.

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Image 3: Grey area of the bridge

Nevertheless, research has shown that after milling is completed, manual adjustments of the CAD/CAM restoration by dental technicians could have a significant effect on improving the restoration fit.19–20 In a mathematical study by Grajower and Lewinstein, it was suggested that the cement space for a crown could be set to at least 50 µm, of which 30 µm is utilised for the cement film and surface roughness, and 20 µm for distortions of the die or of the wax pattern.21 As there is no tooth reduction required for the RRB in this study, the authors chose to set the CAD/CAM software to allow for up to 30 µm space for the resin based Panavia™F cement, which improved the opacity of the cement and prevented the metal shade showing through the incisal edges of the upper central incisors.

Conclusion The evolution of computer aided design/computer aided manufacturing (CAD/CAM) technology in recent years

and its advantages over conventional laboratory methods in the field of crown and bridge fabrication has led to an increased reliance on this technology. It is essential to plan the treatment and liaise with the laboratory to set the CAD/CAM software at the correct parameter in order to achieve a satisfactory film thickness of the luting agent that would provide longevity and aesthetics to the restoration.

References 1. Miyazaki T, Hotta Y, Kunii J, Kuriyama S and Tamaki Y (2009). A review of dental CAD/CAM: Current status and future perspectives from 20 years of experience. Dental Materials Journal; 28(1): 44–56. 2. Duret F & Preston JD (1991). CAD/CAM imaging in dentistry. Current Opinion in Dentistry; 1: 150–154. 3. Kucey BK & Fraser DC (2000). The Procera abutment – the ﬁfth generation abutment for dental implants. Journal of the Canadian Dental Association; 66(8): 445–449. 4. Voitik AJ (2002). CT data and its CAD and CAM utility in implant planning: part I. Journal of Oral Implantology; 28(6): 302–3. 5. Miyazaki T & Hotta Y (2011). CAD⁄CAM systems available for the fabrication of crown and bridge restorations. Australian Dental Journal; 56(1): 97–106.

6. Beuer F, Schweiger J & Edelhoff D (2008). Digital dentistry: an overview of recent developments for CAD/CAM generated restorations. British Dental Journal; 204(9): 505–11. 7. Rochette AL (1973). Attachment of a splint to enamel of lower anterior teeth. Journal of Prosthetic Dentistry; 30(4): 418–423. 8. Djemal S, Setchell D, King P & Wickens J (1999). Longterm survival characteristics of 832 resin-retained bridges and splints provided in a post-graduate teaching hospital between 1978 and 1993. Journal of Oral Rehabilitation; 26: 302–320. 9. Boyer B, Williams VD, Thayer KE, Denehy GE & Diaz Arnold AM (1993). Analysis of debond rates of resinbonded prostheses. Journal of Dental Research; 72: 1244–1248. 10. Dummer PM & Gidden JR (1990). Two-part resin bonded cast metal bridges for use when abutment teeth have unequal effective root surface areas. Restorative Dentistry; 6: 9–14. 11. Miettinen M & Millar BJ (2013). A review of the success and failure characteristics of resin-bonded bridges. British Dental Journal; 215: E3. 12. Hansson O (1994). Clinical results with resin-bonded prostheses and an adhesive cement. Quintessence International; 25: 125–132. 13. Ibrahim AA, Byrne D, Hussey DL & Claffey N (1997). Bond strengths of maxillary anterior base metal resin bonded retainers with different thicknesses. Journal of Prosthetic Dentistry; 78(3): 281–285. 14. Creugers NHJ, Snoek PA, Van’t Hof MA & Kaüyser AF (1990). Clinical performance of resin-bonded bridges: a 5-year prospective study. Part iii: failure characteristics and survival after rebonding. Journal of Oral Rehabilitation; 17: 179–186. 15. Tinschert J, Natt G, Mautsch W, Spiekermann H and Anusavice KJ (2001). Marginal fit of alumina- and zirconia-based fixed partial dentures produced by CAD/CAM systems. Operative Dentistry; 26: 367–374. 16. Shinkai K, Suzuki S, Leinfelder KF & Katoh Yoshiroh (1995). Effect of gap dimension on wear resistance of luting agents. American Journal of Dentistry; 8: 149– 151. 17. Jacobs MS & Windeler AS (1991). An investigation of dental luting cement solubility as a function of the marginal gap. Journal of Prosthetic Dentistry; 65: 436– 442. 18. White SN, Yu Z (1992). Film thickness of new adhesive luting agents. Journal of Prosthetic Dentistry; 67: 782– 5. 19. Witkowski S, Komine F & Gerds T (2006). Marginal accuracy of titanium copings fabricated by casting and CAD/CAM techniques. Journal of Prosthetic Dentistry; 96: 47–52. 20. Kale E, Seker E, Yilmaz B & Özcelik TB (2016). Effect of cement space on the marginal fit of CAD-CAMfabricated monolithic zirconia crowns. Journal of Prosthetic Dentistry; 116(6): 890–895. 21. Grajower R & Lewinstein I (1993). A mathematical treatise on the fit of crown castings. Journal of Prosthetic Dentistry; 49: 663–74.

Image 4: Final bridge the

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It fits too well – the modern problems with CAD/CAM technology and resin bonded bridgework: A case study. Materials and equipment CPD – 60 minutes To complete your CPD, store your records and print a certiﬁcate, please visit www.dta-uk.org and log in using your member details. Q1 In terms of retainer thickness, what dimensions have been shown to be less resistant to dislodgement? A < 0.7 mm B < 0.9 mm C > 0.6 mm D > 0.9 mm Q2 Debonding of metal-framed work restorations is a common problem. What percentage does the author highlight from the study of Dummer and Gidden (1990)? A 92.3% B 92.4% C 92.5% D 92.6% Q3 In relation to fit, what was the dimensional space between the retainer and the tooth to allow for cement? A 25 μm B 30 μm C 35 μm D 40 μm Q4 The film thickness of the luting material can be influenced by a number of factors. They are: A The viscosity of the unset material and its setting time B Dimension of the ﬁller particles (size, shape, etc.) C The substrate that the materials will bond to D All of the factors mentioned above Q5 During the early 1980s, what alternative alloy was used instead of gold? A Chrome cobalt B Titanium C Nickel-chromium alloy D Titanium alloy Q6 The authors highlight a ‘clinically acceptable’ marginal fit from the literature. What was this value? A < 50 μm B < 60 μm C > 50 μm D > 60 μm

Q7 Rochette highlighted a perforated cast retainer for a temporary restoration. What was the service life? A 6 months B 1 year C 1 year 6 months D 2 years Q8 Within the case study, what was the patient having replaced? A Upper lateral incisors B Upper incisors C Left lateral incisor D Right lateral incisor Q9 What specific cement was used for the bridge? A PanaviaTM B PaniviaTM F C PanaviaTM F D PaniviaTM Q10 A common factor for a failure of a metal-framed resin retained bridge is: A Delamination or porcelain fracture B Cement debond C Caries D All of the above

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medicalemergencies

■ Medical emergencies in a dental environment Aims and Objectives: Principle 8 Always put patients’ safety first ■ Educational aims: – to highlight potential medical emergencies within the dental profession – to inform the reader of choking, anaphylaxis, epileptic fits and seizures within individuals ■ CPD outcomes: – to highlight signs and symptoms of choking, anaphylaxis, epileptic fits and seizures – to highlight potential treatment of individuals if such an event occurs

Introduction ‘A patient could collapse on any premises at any time, whether they have received treatment or not. It is therefore essential that ALL registrants are trained in dealing with medical emergencies …’ (General Dental Council ‘Scope of Practice’, 2013). Additionally, not just registrants but all staff members need to be prepared and knowledgeable in how to deal with medical emergencies at any time (Jevon, 2012). Although emergencies occurring in dental laboratories are relatively rare, there is a public expectation that dental healthcare professionals are expected to know how to deal with any emergency, should it occur. This article focuses on choking, and in the next edition of TT we will cover anaphylaxis and seizures.

Choking by Lorraine Madley, RN, Cert Ed, BSc (Hons)

Fig. 1: Hand position for abdominal thrusts

Choking can be defined as mild or severe (Resuscitation Council UK, 2015) and although it is uncommon in adults, following a survey of 300 dentists over a 12-month period, they reported that choking had occurred in 27 patients in total (4.6%) (Girdler and Smith, 1999). Therefore, it is imperative that the correct diagnosis, together with the following treatment, be made quickly in order to prevent cardiac arrest (Wong & Tariq 2011). ■ Mild choking is signified by coughing, and hopefully the patient being able to tell you what the problem is, in which case encourage them to continue coughing and monitor their condition. ■ Severe choking is life threatening. The patient will be unable to cough or talk and immediate action needs to be taken.

Treatment

Fig. 2: Back blows on an infant

Deliver up to five sharp blows between the shoulder blades with sufficient force to dislodge the obstruction. This may be enough to reverse the emergency; however, if the choking persists, perform up to five abdominal thrusts. Stand behind the patient and place one clenched fist between the naval and ribcage, place your other hand over the

top and thrust inwards and upwards (Figure 1). Applying pressure to the lungs hopefully forces the object out. If this does not work, alternate five back blows and five abdominal thrusts until successful. In approximately 50% of cases, back blows and abdominal thrusts are needed (Resuscitation Council UK, 2015). After two to three unsuccessful cycles, call 999. If the patient becomes unconscious, lower them to the floor and commence CPR immediately. The actions of both compressions and breaths may force the object out or move it sufficiently for air to flow around it. Do not perform abdominal thrusts on heavily pregnant women or infants. Do ensure the patient goes to hospital if abdominal thrusts have been performed to rule out any internal injury. Choking infants: The above sequence can be performed on any person over the age of one year (Resuscitation Council UK, 2015). A choking infant is managed by performing back blows (Figure 2), and then if needed, chest thrusts (Figure 3 – overleaf) in sequences of up to five each. the

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medicalemergencies Assess severity

Fig. 3: Chest thrusts on an infant NO abdominal thrusts are performed. The algorithm for dealing with choking for all ages is shown in Figure 4.

Ineffective cough (Severe)

Effective cough (Mild)

Summary Whilst medical emergencies in dental environments are rare, their onset may be sudden and staff will need regular training updates and familiarisation with equipment and drugs kept in order to treat patients quickly and appropriately.

Conscious 5 back blows 5 thrusts

Unconscious Start CPR

(chest for infant, abdominal for child and adult)

Encourage cough Continue to check for deterioration to ineffective cough or relief of obstruction

References ■ General Dental Council. Scope of Practice. [online] 2013 Available at: https://www.gdc-uk.org/ professionals/standards/st-scope-of-practice [Accessed July 2017]. ■ Girdler N & Smith D (1999). Prevalence of emergency events in British dental practice and emergency management of skills of British dentists. Resuscitation; 41, pp.159–167. ■ Jevon P (2012). Updated guidance on medical emergencies and resuscitation in the dental practice. British Dental Journal; 1; pp. 41–43. ■ Resuscitation Council (UK). Quality standards for cardiopulmonary resuscitation practice and training – Primary dental care – Quality Standards. [online] 2013 Available at: https://www.resus.org.uk/quality-standards/ primary-dental-care-quality-standards-for-cpr [Accessed July 2017]. ■ Resuscitation Council (UK). Adult basic life support and automated external deﬁbrillation. [online] 2015 Available at: https://www.resus.org.uk/resuscitation -guidelines/adult-basic-life-support-and-automated -external-deﬁbrillation/#foreign. [Accessed July 2017]. ■ Resuscitation Council (UK). Paediatric basic life support. [online] 2015 Available at: https://www.resus.org.uk/ resuscitation-guidelines/paediatric-basic-life-support [Accessed July 2017]. ■ Wong SC & Tariq SM (2011). Cardiac arrest following foreign-body aspiration, Respiratory Care; 56, 4 pp. 527–529.

Lorraine Madley Lorraine is a Senior Lecturer in Resuscitation with Middlesex University and has been teaching in dental settings for more than 15 years. Lorraine holds both the Advanced Life Support Providers Certiﬁcate and the European Paediatric Life Support Certiﬁcate and currently teaches a wide variety of healthcare professionals plus nursing and midwifery students. the

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Fig. 4: The Choking Algorithm

Medical Emergencies in a Dental Environment – Medical emergency CPD – 30 minutes To complete your CPD, store your records and print a certiﬁcate, please visit www.dta-uk.org and log in using your member details. Q1 Within the choking algorithm, how many back blows and thrusts for one cycle are recommended to be performed on a conscious individual who is choking? B 5 back blows and 5 thrusts A 3 back blows and 5 thrusts C 5 back blows and 3 thrusts D 5 back blows and 4 thrusts Q2 In approximately how many choking cases are back blows and abdominal thrusts required? A 40% B 45% C 50% D 55% Q3 When a person is choking, you should not perform abdominal thrusts when a patient is: A Over the age of 65 years B An infant C Over the age of 65 years or an infant D Heavily pregnant or an infant Q4 Which of the following is NOT advice recommended by this author? A Ensure the patient goes to hospital if abdominal thrusts have been performed B Abdominal thrusts are recommended for children and adults C CPR should be provided for severe cases where the patient is unconscious D Infants should not be treated with thrusts or m eme edical blows r

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Q5 After how many unsuccessful cycles of blows and thrusts should you call 999? A 2 B 2–3 C 1–2 D 3+

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prostheticcasestudy

■ Provision of a maxillary complete denture and complex mandibular unilateral free-end saddle cobalt chromium based partial denture Aims and Objectives: Principle 7 Maintain, develop and work within your professional knowledge and skills ■ Educational aim: – to review a patient prosthetic case study ■ CPD outcomes: – to consider the techniques used in this case study – to consider the specific stages involved in creating the appliances – to understand the patient-centred approach to the aesthetics

by Dr Finlay Sutton

His general dental practitioner referred this 61-year-old man, whose primary concerns around the lower denture, he said, affected his self-confidence. His recently made lower denture didn’t stay in place and was uncomfortable when eating, necessitating frequent interruption of meals with the need to clean it and apply more fixative cream. The patient no longer enjoyed food, felt self-conscious and started to experience gum soreness.

Dental wish list: ■ Make a lower denture that feels secure in my mouth and reduces the amount of food that gets under it when I eat. ■ Advise whether I would be suited to a lower denture that is secured on implants. ■ Make the denture look natural.

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Diagnoses: Dr A Finlay Sutton, BDS, DGDP (UK), MSc, MFDS RCS Ed, MRD RCS Ed, PhD, FDS (Rest Dent) RCS Ed Registered Specialist in Restorative Dentistry, Prosthodontics, Endodontics & Periodontics Garstang Dental Referral Practice Weind House, Park Hill Road, Garstang Lancashire PR3 1EL United Kingdom Tel: 01995 606091 www.garstangdrp.co.uk

1. The maxillary and mandibular acrylic based dentures had poor tissue fit and were inadequately extended. The design problems resulted in both dentures having poor retention, support and stability. The patient required considerable amounts of fixative to function with the dentures in place. 2. UR6 was heavily restored with a large MOD amalgam restoration and had root canal fillings, which were undercondensed and there were periradicular areas on the apices. There

Fig. 1 Pre-treatment – without the partial dentures in situ, showing overerupted upper right molars and marked resorption of the mandibular ridge on the lower right hand side

7. 8.

was 50% alveolar bone loss on this tooth. It had over erupted and the opposing mandibular edentulous ridge showed marked resorption in this region (see figures below). UR7 had an MO amalgam with 50% alveolar bone loss. The LL4 had a DO amalgam filling with 50% bone loss distally and 30% bone loss mesially. The LL3 had a cavity distally with a periradicular area and exhibited 20% bone loss. The edentulous saddles in the maxilla and mandible had fairly shallow sulcus depth and high frenal attachments. Fair to poor standard of oral hygiene. Poor dental aesthetics.

Fig. 2 Pre-treatment – with the partial dentures in situ

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prostheticcasestudy Treatment options discussed with the patient 1. Do nothing. The patient did not want this option. 2. In the upper arch, remove the heavily restored UR6 and UR7 and provide a complete upper denture. In the lower arch, provide a cobalt chromium based partial mandibular partial denture using the remaining teeth and edentulous saddles to support the denture (Fig. 4), with the potential for implant provision in the future should this be functionally necessary. LL3 root canal treat, decoronate and use as an overdenture abutment. LL4 to be used to support

and retain the partial denture. LL6 decoronate and use as an overdenture abutment. LL7 to be used to support and retain the partial denture. This is the option the patient requested. 3. As option 2, with incorporation of 2 dental implants to support and retain the lower cobalt chromium based partial denture in the lower right area of the mouth. The patient did not want this option. 4. Remove all upper and lower natural teeth and replace with complete upper and lower dentures. The patient did not want this option.

5. Remove all of the teeth, place dental implants and implant supported dentures. 6. Remove all of the teeth, place dental implants and fixed prostheses. The patient did not want this option. 7. Combinations of the above. Following consultation and discussion of the above treatment options, the patient chose to have option two: a complete maxillary denture and a partial cobalt chromium based mandibular denture. The clinical situation and treatment process is shown in detail with photographs. The patient was successfully rehabilitated and his quality of life considerably improved. The clinical work was provided by Finlay and the technical work by Rowan.

Fig. 3 Pre-treatment mandibular arch with the partial denture in situ

Fig. 4 Cobalt chromium based mandibular partial denture design for this patient. Support derived from the overdenture abutments LL3, LL6, the LL4 LL7 and a fully extended free end saddle. Retention derived from clasping the LL4 and LL7 the

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Fig. 5 Mandibular special tray border moulded with greenstick compound. Attention paid to the free end saddle to mimic a complete mandibular denture, to maximise stability

Fig. 6 Maxillary special tray with definitive impression made in light bodied silicone (Doric Definition - Schottlander)

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Fig. 7 Inter maxillary registration rims. The blocks touch posteriorly simultaneously in centric relation. Grooves are cut into the rims to allow unambiguous location of the rims with bite registration material

Fig. 8 Occlusal plane of the maxillary rim carved parallel with the ala-tragus line

Fig. 9 Pre-extraction photographs assist with creating good lip support

Fig. 10 Dentate photograph and carved registration rims are used by Rowan (dental technician) to arrange the artificial teeth

Fig. 11 Inter maxillary registration rims are fixed together with bite registration material Futar D

Fig. 12 Face bow transfer used on the maxillary rim the

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Fig. 13 Mounted definitive casts with denture teeth positioned - full contour wax up

Fig. 14 Cobalt chromium framework trial insertion in the mouth

Fig. 15 Finished dentures with Schottlander Enigmalife teeth

Fig. 16 Finished dentures with Schottlander Enigmalife teeth

Special thanks goes to Rowan Garstang (dental technician) who produced the beautiful dental laboratory work in this article. Rowan and Finlay have worked together for the past 19 years. Fig. 17 Finished dentures with Schottlander Enigmalife teeth the

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Fig. 18 Finished dentures fitted with Schottlander Enigmalife teeth Fig. 19 Comparison of dentate photograph and the new dentures. The patient had complete control over the positioning of his new teeth

Provision of a maxillary complete denture and complex mandibular unilateral free-end saddle cobalt chromium based partial denture. Materials and equipment CPD – 60 minutes To complete your CPD, store your records and print a certiﬁcate, please visit www.dta-uk.org and log in using your member details. Q1 In Fig. 3, which tooth/teeth below are not in the picture? A Upper right molars B 33 and 34 C 37 D LR6 and 7

Q6 Which form of articulator was chosen for this case? A Simple hinge B Plasterless C Semi adjustable D Digital pantograph

Q2 Which prosthetic option did the patient choose (or consent to)? A Keep the remaining teeth and have new upper and lower partial dentures B Have a complete upper and a partial lower denture C Have an upper denture and a lower partial supported on two implants D Remove all the teeth and have implant ﬁxed prosthesis

Q7 The chrome cobalt framework clearly shows the: A Wrought gold I bar for the 43 B Spaces for the implants in the LR 3 & 4 region C A fully extended retention section on the right side D Full ring clasp with buccal retention arm on the R7

Q3 In the design of a removable partial denture, what does the gold I bar clasp provide? A Retention B Bracing C Stability D Occlusal support Q4 To maximise lower denture stability, the clinician: A Used impregum in a stock tray B Border moulded by using greenstick C Used rest seats on both sides of the partial D Developed a peripheral seal Q5 The operator determined the occlusal plane as anterior to posterior line: A Parallel to the inter papillary line B Parallel to the ala-tragus line m C By the facebow transfer and ateria equi ls device pme D Via trimmed inter nt maxillary registration rims

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Q8 This denture case study on the patient’s right side: A Used all the provided posterior denture teeth B Did not use the 17 and the 47 C Did not use the 27 and 37 D Did not use the R4 and R7 Q9 How did the clinician help the patient achieve a good result? A By using copies of the patient’s younger age photographs B Working with the patient to seek out his tooth position wishes C Team working with the dental technician in the practice D Working on a ‘look natural’ principle and all the above Q10 What was NOT the patient’s wish during treatment in this case? A Make the lower denture more secure B Provide an immediate replacement complete set of dentures C Reduce the food getting under the denture D Look more natural

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cad/cam

■ The developments in hybrid ceramics for CAD/CAM manufacturing Aims and Objectives: Principle 7 Maintain, develop and work within your professional knowledge and skills ■ Educational aim: – to have an awareness of the new materials that are being developed for single CAD/CAM restorations ■ CPD outcomes: – to develop an awareness of competing restoration methods and materials – to be aware of the new complex materials being developed for CAD/CAM single tooth restorations – to be aware of the developments in oral imaging related to CAD/CAM restorations

The last 30 years have seen tremendous advances in CAD/CAM dental restorations, making this technology increasingly popular in daily practice. Above all, improvements in intraoral cameras leading to powder-free scans, true-colour displays and smaller camera heads have substantially simplified the clinical handling of CAD/CAM systems.

Fig. A: Molar crown milled from the hybrid ceramic material SHOFU Block HC (SHOFU Dental, Ratingen, Germany)

he latest software solutions allow dental professionals to operate these systems intuitively after a relatively short learning curve and to use largely automatic restoration designs.1 All these aspects have made chairside restorations more efficient in terms of data collection and design procedures. Further innovations have been achieved in the field of CAD/CAM restorative materials. Two directions of development can be observed here. One approach has been to develop new high strength ceramics, minimising the risk of material-related restoration failure. Both high strength glass ceramics (lithium disilicate, zirconia-reinforced lithium silicate) and partially stabilised zirconia have gained acceptance. However, due to their increased strength, these materials usually need to be first milled in a presintered state and then finally sintered in a separate firing process giving them their definitive strength. These processes require additional equipment (furnaces)

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in dental practices and make restorations more time-consuming.2 Another approach has been to combine ceramics and polymers into a new material type known as hybrid ceramics.2–3 This group of materials is also described as CAD/CAM high performance polymers. The materials (e.g. SHOFU Block HC, SHOFU Dental GmbH, Ratingen, Germany; Lava Ultimate, 3M Espe, Seefeld, Germany; Cerasmart, GC, Bad Homburg, Germany) are made by embedding nano-ceramic particles in a very hard polymer matrix4. The industrial polymerisation process of this matrix, using both light and heat, significantly improves material properties. The mechanical properties of hybrid ceramics range between those of traditional glass ceramics and light-cured composite materials.2–4 Their filler loads vary between approximately 60% and 80% by weight, depending on the manufacturer, and their flexural strengths

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cad/cam have been found to be 120–200 MPa in various studies.5,6 Their moduli of elasticity range from 9–14.5 GPa, coming relatively close to the E-modulus of natural dentin (17–29 GPa).2,7 A special hybrid material has been developed by infiltrating a fine structure ceramic network with an acrylate polymer mixture (Vita Enamic, Vita Zahnfabrik, Bad Säckingen, Germany). This material, which is also described as a hybrid ceramic, has filler loads of up to 86% by weight, leading to a flexural strength of 140 MPa and a modulus of elasticity of 28 GPa.5,7 Since the modulus of elasticity of hybrid ceramics comes closer to that of natural dentin, restorations can be expected to distribute stresses more homogeneously.2 A ‘damping effect’ has been postulated for hybrid ceramics, thanks to the favourable combination of a dentin-like modulus of elasticity and lower hardness.4 Moreover, the low hardness and very good ‘polishability’ of these materials clearly reduce antagonist abrasion, as compared to traditional ceramics.3,4,8,9 And the low hardness of hybrid ceramics also makes milling easier and processing times much shorter, as compared to ceramics. What is more, the flexibility of hybrid ceramics is considerably higher than that of traditional ceramics, reducing the risk of marginal chipping during the milling

Fig. B: Finishing the occlusal fissure relief with a suitable fine-grit diamond bur (8390.104.016, Komet Dental, Lemgo, Germany)

process. This is particularly beneficial when restorations with thin parts have to be made.2 It also helps to greatly reduce tool wear. Tools may need to be changed after 15–20 units when milling ceramics, whereas more than 50 restorations can be made with one set of instruments when milling hybrid ceramics.2–4 Like glass ceramics, hybrid materials also show a chameleon effect facilitating shade matching. And the shades of hybrid ceramic restorations can be relatively easily and quickly individualised using light-cured stains. Hybrid ceramics are particularly suitable for chairside restorations since they combine favourable mechanical properties with quick milling and polishing so that processing times are short.2–4 On the basis of the in-vitro data currently

available, hybrid ceramics are recommended for use as inlay, partial crown and veneer materials. All hybrid ceramics on the market, except Lava Ultimate, are indicated for anterior and posterior crowns. At present all hybrid ceramics require adhesive cementation after surface conditioning by either sandblasting at reduced pressures (1–1.5 bar) or application of a special primer. Irrespective of the conditioning method used, a chemical primer (silane) needs to be applied.10 Thanks to favourable properties such as good millability and polishability, the new group of hybrid ceramic materials allows the operator to efficiently fabricate singletooth restorations in only one appointment. Additional benefits include dentin-like elasticity and low antagonist

Fig. C a–b: Polishing the restoration with ‘Brownies’ and ‘Greenies’ (Amalgam Polishing Kit, SHOFU Dental, Ratingen, Germany) the

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cad/cam Fig. D: High gloss polishing with diamond paste (Dura-Polish DIA, SHOFU Dental, Ratingen, Germany)

abrasion. Current in-vitro data regarding mechanical characteristics, abrasion behaviour and discolouration tendency seem to be promising. However, it should also be taken into account that there is still a lack of long-term clinical data that would be indispensable to any further scientific assessment of this innovative material category.

So, for the time being it will be absolutely necessary to observe the restricted indications for use given by the manufacturers, and also the recommended preparation methods and minimum material thicknesses when using hybrid ceramics in clinical practice. The use of hybrid ceramics for singletooth restorations can be advised only in combination with a suitable adhesive cementation system.

The developments in hybrid ceramics for CAD/CAM manufacturing. Materials and equipment CPD – 30 minutes To complete your CPD, store your records and print a certiﬁcate, please visit www.dta-uk.org and log in using your member details. Q1 What does the author consider are the major improvements in CAD/CAM dental conservation restorations? A Improvements in intraoral cameras B True colour displays C Popularity and all answers D Intuitive learning for user Q2 According to the writer, what is NOT an example of high strength glass ceramics or a stabilised material? A Zirconia B Lithium disilicate C CAD/CAM high performance polymers D Zirconia-reinforced lithium silicate Q3 CAD/CAM high performance polymers (hybrid ceramics) are simply described as a: A Combination low fusing silicate glass B Nano-ceramic particles in a very hard polymer matrix C Acrylate monomer mixture in zirconium powder D Hybrid of nano non-glass ceramics Q4 Which are said to be the favourable properties of the new hybrid ceramics? A Good millability, and all answers B Dentin-like elasticity and low antagonist abrasion C Polishability, and b and d only D Resistance to discolouration Q5 Prior to cementing in the oral cavity, the author suggests that the cleaned fit surface should be treated with: A Hydrochloric acid B Sandblasting C Ureic acid D Silane

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inut

Fig. E: Surface conditioning by roughening (sandblasting/etching) and application of a special primer (HC Primer, SHOFU Dental, Ratingen, Germany) ■ This is an excerpt of an article from dentist Ila Davarpanah, Hanau / Gemany, first published in DZW Kompakt, March 2017, Zahnärztlicher Fach-Verlag, Herne / Germany. ■ For further details please contact the Shofu office 01732 783 580 or sales@shofu.co.uk

References 1 Santos GC Jr, Santos MJ Jr, Rizkalla AS, Madani DA, ElMowafy O (2013). Overview of CEREC CAD/CAM chairside system. Gen Dent; 61(1): 36–40. 2 Horvarth S, Spitznagel F, Gierthmühlen P (2016). Neue Gesichtspunkte der restaurativen Zahnmedizin. Hybridmaterialien – Indikation und Bewährung, Zahnärztlich. Mitteilungen; 106: 1134–1140. 3 Mainjot AK, Dupont NM, Oudkerk JC, Dewael TY, Sadoun MJ (2016). From Artisanal to CAD-CAM Blocks: State of the Art of Indirect Composites. J Dent Res; 95(5): 487–495. 4 Ruse ND, Sadoun MJ (2014). Resin-composite blocks for dental CAD/CAM applications. J Dent Res; 93(12): 1232–1234. 5 Stawarczyk B, Liebermann A, Eichberger M, Güth J-F (2015). Evaluation of mechanical and optical behaviour of current esthetic dental restorative CAD/CAM composites. J Mech Behav Bio-med Mater; 55: 1–11. 6 Awada A, Nathanson D (2015). Mechanical properties of resin-ceramic CAD/CAM restorative materials. J Prosthet Dent; 114(4): 587–593. 7 Lauvahutanon S, Takahashi H, Shiozawa M, Iwasaki N, Asakawa Y, Oki M, Finger WJ, Ark-sornnukit M (2014). Mechanical properties of composite resin blocks for CAD/CAM. Dent Mater J; 33(5): 705–710. 8 Lauvahutanon S, Takahashi H, Oki M, Arksornnukit M, Kanehira M, Finger WJ (2015). In vitro evaluation of the wear resistance of composite resin blocks for CAD/CAM. Dent Mater J; 34(4): 495–502. 9 Koizumi H, Saiki O, Nogawa H, Hiraba H, Okazaki T, Matsumura H (2015). Surface roughness and gloss of current CAD/CAM resin composites before and after toothbrush abrasion. Dent Mater J; 34(6): 881–887. 10 Spitznagel FA, Horvath SD, Guess PC, Blatz MB (2014): Resin Bond to Indirect Composite and New Ceramic/Polymer Materials: A Review of the Literature. J Esth Rest Dent; 26: 382–392.

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dentaltechnologyshowcase

■ A line-up like no other In order to provide the highest standard of education, the Dental Technology Showcase (DTS) 2018 has once again brought together a fantastic speaker line-up for all delegates to enjoy. Among the speakers in the DTS Lecture Theatre – which has been programmed by the Dental Technicians Guild (DTG) – will be John Wibberley, Stefan Picha, Dr Finlay Sutton, George Morgan and Phil Reddington. They will cover everything from dentures to high performance polymer materials and enhancing aesthetics of prostheses. The Orthodontic Technicians Association (OTA) and British Association of Clinical

Dental Technology (BACDT) will be supporting sessions that cover systemic disease in older people, the evolution of light curing, occlusal management and oral cancer, among other topics. Speakers here will include Professor StJohn Crean, Stephen Prime, Derren Neve, Matt Burnell, Steve Taylor, Finlay Sutton, Jonathan Hughes, Craig Parker and Andrea Johnson, among many others. Don’t miss out and register your whole team for FREE from the website!

■ DTS 2018 will be held on Friday 18 and Saturday 19 May at the NEC in Birmingham, co-located with the British Dental Conference and Dentistry Show. ■ For further details, visit www.the-dts.co.uk, call 020 7348 5270 or email: dts@closerstillmedia.com

■ In case you hadn’t noticed – TT’s gone digital In case you missed the heads up in the February edition and were wondering when you would receive your April copy of TT … In case you’re wondering why this issue of TT is heavier that usual … In case you’re searching for the CPD answer sheet that usually features in the back of TT … We have made some changes!

the

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he Technologist is now a 40-page, quarterly journal that you will receive at the beginning of May, August, November and February. That means you have more time to complete your CPD! You will notice that the CPD questions now feature with each article making it easier for you to read and answer. There are no answer sheets because all CPD is to be completed online; there is no longer a paper-based answer sheet.

■ If you have any queries or need some assistance to ‘go digital’ then please contact Sue at the DTA office.

may 2018 35

gettingtoknowyou

■ Getting To Know You... It brings us great pleasure to launch our brand new Getting To Know You section. In each issue we will interview a prominent person in the world of dental technology. Our first feature is dedicated to Delroy Reeves, DTA’s very own president, who is based in London where he runs a private dental laboratory. ■ How long have you been involved in dental technology and how did it start? I’ve been involved in dental technology for around 40 years. It all started back in Jamaica. I was doing a part-time job in a men’s store and upstairs was a dental practice with a lab on the premises. Every lunchtime a technician would stop by the store for a chat and we became very good friends. On my lunch break, I would go up to the lab out of interest. While observing the technician at work – and getting a good sniff of heated pink wax – I watched each tooth being placed into the wax and forming a denture. Interesting, I thought. After a couple of visits I started to be given different tasks – such as adjusting a tooth by trimming it to fit onto the arch, under his guidance and instructions. The more and more I did, the more this technician thing got hold of me! A year and a half later things changed in a huge way. The technician came to see me with the news that he was leaving to join his wife in the USA and that I had been put forward as his successor. Shocked, I asked, why me? His reply was, ‘You’re hooked and you’re the person I most trust to carry on – and you’re respected by the dentist.’

I assumed the position, with the dentist as my main tutor – and a brilliant one he was too. Dr Barry Miller guided me on the path I have chosen in becoming a dental technologist.

■ What do you enjoy the most about your job?

■ What happens on a typical day at work?

Mostly it’s the challenges and unpredictability that I most enjoy. No two days are the same. You realise there are always ways of doing things more easily and quickly and getting the desired results.

I typically start the day by having an early morning run, and then I would go on my rounds. Some days I may see patients for colour matching. At the end of all that I would do all my finishings and impression castings, as well as preparing cases for the following day.

Seeing other technologists at their work helps people gain valuable ideas and techniques. Other dental professionals sharing best practice, while having a great rapport and respect, regardless of seniority or status, does help to advance the profession. the

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36 may 2018

gettingtoknowyou L to R: Tony Griffin, Delroy Reeves & John Stacey

us to be close to our interest would undoubtedly bring into focus where we fit into our universe as living beings and how we deal with our planet to improve the quality of life on earth. ■ What are the three things you check about your work or business every day? 1 Satisfaction 2 Quality 3 Reward in kind – prompt payment at the end ■ What do you do when you’re not working? When I’m not working I go for runs or walks in Epping Forest, observing the colours and nature at work. I also enjoy finding time to sit by the river. For me time, I meditate, listen to music, read through The Technologist and catch up on my study hours, occasionally! ■ What is your favourite holiday destination and why? I love Portugal and Italy. In Portugal, I can book a coach trip and be in Lisbon. From Vilamoura, I can also travel to the port-producing area of Porto. In Italy, I go visiting the Vatican, and Venice riding the gondolas, visiting museums and glass-blowing establishments – and making good use of the wonderful foods and culinary delights. ■ Who would you take on a date into space and why? As a family that is fascinated with astronomy, I would certainly take my wife and son, who are into sci-fi movies. For the

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■ Who are your three heroes? 1 My mother and father 2 Nelson Mandela 3 Bob Marley ■ If you were stranded on a desert island, what three things would you want to have and why? One of the three things I would need with me is a copy of The Technologist as it would remind me of the things I need to do apart from my study hours – I would also need to know what articles Tony Griffin is writing! TT would certainly keep me on track with thinking about all the DTA’s strategic plans and I could use it as a cooling fan and umbrella when the heat became unbearable and the dust was whipped up by the wind! As someone of faith and a deputy churchwarden, I would take Hymn 332

from the complete Anglican Hymns Old and New – I the Lord of sea and sky, I have heard my people cry. This hymn would give me hope, calmness and selfassurance, regardless of the difficulties. There is a bright light that will lead me out of the desert. The third thing I would take would be the inspirational speeches by Dr Martin Luther King Jr, Barack Obama and Archbishop Desmond Tutu. They always make me think strategically about the future. ■ What makes The Technologist journal essential reading for you? It is the Van Gogh for every technologist. True and unique, it relays good quality articles on all aspects of dental technology from legal issues, infection control, medical emergencies and all the required subjects and disciplines the GDC specifies, as well as any changes in dental regulation. The CPD provided is extremely high quality, which others use as their benchmark and lecturers refer their students to work on as part of their studies. For me, The Technologist offers the uniqueness of an archive of historical importance. I can search past journals to see how far we have come, the contribution made and those who have made the difference. TT is my prize journal, especially when I am travelling around. It is current and it’s informative: it is professionally produced and impressive. But most of all, I can do all my study hours as offered by the Dental Technologist Association.

may 2018 37

The Dental Technologists Association

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Please return this form to: The Dental Technologists Association, Kestrel Court, Waterwells Drive Waterwells Business Park, Gloucester GL2 2AT

The professional representative body for dental technicians the

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