International Dentistry Australasian Edition - Vol. 11 No. 2 by Henry Schein ANZ

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VOL. 1 1 NO. 2 IN THIS ISSUE

S. Jay Bowman Clear Collection instruments for clear aligner treatments Javier MartĂnez Osorio, Sebastiana Arroyo BotĂŠ Supernumerary teeth: diagnosis and treatment Claudio Novelli edelweiss VENEERs and OCCLUSION-VDs: A holistic concept for bio-aesthetics and function Johan Hartshorne Should I incorporate a cantilever extension on an implant-supported fixed dental prosthesis (FDP) or not? Joannis Katsoulis Digital possibilities for making implant prosthetics Linda Greenwall Tooth whitening: the last 25 years Deepa Shah Adhesive dentistry and the worn dentition

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Contents Volume 11 No. 2

Clinical

Case Report

Clear Collection instruments for clear aligner treatments S. Jay Bowman

Supernumerary teeth: diagnosis and treatment Javier Martínez Osorio, Sebastiana Arroyo Boté

26 Interview

edelweiss VENEERs and OCCLUSION-VDs: A holistic concept for bio-aesthetics and function Claudio Novelli

36 Clinical

Should I incorporate a cantilever extension on an implant-supported fixed dental prosthesis (FDP) or not? Johan Hartshorne

40 Clinical

Digital possibilities for making implant prosthetics Joannis Katsoulis

44 Clinical

Tooth whitening: the last 25 years Linda Greenwall

52 Clinical

Adhesive dentistry and the worn dentition Deepa Shah

62 Products

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Henry Schein Halas staff join together to build toys for Camp Quality Earlier this year, staff at Henry Schein Halas joined together in a toy building challenge for Camp Quality. Provided with a mystery box of whacky wooden parts, paint, stickers and glue, teams were challenged to combine components and produce a range of high quality children’s toys. Team members worked hard together trying to stay on target to create these toys and make sure they were completed by the proposed deadline and were encouraged to produce toys to the best possible quality, as if they were making the toy for their own child. There was a central station to wash and reuse paint brushes and dryers to finish the toys with a shiny gloss. To top it off, the teams packed up their toys back into their mystery box, and then transformed the box with more paint and stickers! With a total of over 200 people participating in teams of 8; there were over 25 boxes each with 4 toys in them to donate! Each box contained enough wooden pieces for the teams to build and decorate two cars, two jewellery boxes and flower toys. The teams were happy that their finished masterpieces were going towards a wonderful cause. Anita Birkin, Marketing Director of Henry Schein Halas, remarked ‘it was a wonderful opportunity to create something with a team you didn’t know and to create a toy for a child you didn’t know. It was a great way to get to know people and provide a gift for a child’ Camp Quality’s purpose is to create a better life for every child living with cancer in Australia. They are committed to delivering national programs that build resilience and optimistic behaviours for all children (0-13 years) living with cancer. Together with a financial donation, these toys will change the lives of children who really deserve a break from the harsh realities of their illness. Staff members also wrote cards of hope so that the children knew we were thinking of them. At Henry Schein Halas, we really cherish the moments where we get to work together knowing our team building is creating a brighter future for children. On the 23rd February 2016, Henry Schein Halas had a sale day with a percentage of sales being donated to Camp Quality. We were pleased to be able hand over a check for $7500 after the sale. This money will allow two families to participate. Thank you to all our customers who supported us on the day, your support allowed us to make this donation. For more information on Camp Quality visit their website: www.campquality.org.au

Vol. 11 No. 2 ISSN 2071-7962 PUBLISHING EDITOR Ursula Jenkins

EDITOR-IN-CHIEF Prof Dr Marco Ferrari

ASSOCIATE EDITORS Prof Cecilia Goracci Prof Simone Grandini Prof Andre van Zyl

EDITORIAL REVIEW BOARD Prof Paul V Abbott Prof Antonio Apicella Prof Piero Balleri Dr Marius Bredell Prof Kurt-W Bütow Prof Ji-hua Chen Prof Ricardo Marins de Carvalho Prof Carel L Davidson Prof Massimo De Sanctis Dr Carlo Ercoli Prof Livio Gallottini Prof Roberto Giorgetti Dr Patrick J Henry Prof Dr Reinhard Hickel Dr Sascha A Jovanovic Prof Ivo Krejci Dr Gerard Kugel Prof Edward Lynch Prof Ian Meyers Prof Maria Fidela de Lima Navarro Prof Hien Ngo Prof Antonella Polimeni Prof Eric Reynolds Prof Jean-Francois Roulet Prof N Dorin Ruse Prof Andre P Saadoun Prof Errol Stein Prof Lawrence Stephen Prof Zrinka Tarle Prof Franklin R Tay Prof Manuel Toledano Dr Bernard Touati Prof Laurence Walsh Prof Fernando Zarone Dr Daniel Ziskind PRINTED BY KHL PRINTING, Singapore International Dentistry - Australasian Edition is published by Modern Dentistry Media CC, PO BOX 76021 WENDYWOOD 2144 SOUTH AFRICA Tel: +27 11 702-3195 Fax: +27 (0)86-568-1116 E-mail: dentsa@iafrica.com www.moderndentistrymedia.com

© COPYRIGHT All rights reserved. No editorial matter published in International Dentistry Australasian Edition may be reproduced in any form or language without the written permission of the publishers. While every effort is made to ensure accurate reproduction, the authors, publishers and their employees or agents shall not be held responsible or in any way liable for errors, omissions or inaccuracies in the publication whether arising from negligence or otherwise or for any consequence arising therefrom. Published in association with

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CLINICAL

Clear Collection instruments for clear aligner treatments

S. Jay Bowman1

In part 1 of a series, Dr. S. Jay Bowman explores instruments that help increase the utility of aligners and expand the scope of appropriate applications

Let’s be clear: enhancing aligner treatments

Dr. S. Jay Bowman, DMD, MSD, is a Diplomate of the American Board of Orthodontics and a member of the Edward H. Angle Society of Orthodontists. He developed and teaches the Straightwire course at the University of Michigan, is an Adjunct Associate Professor at Saint Louis University, an Assistant Clinical Professor at Case Western Reserve University, and Visiting Clinical Lecturer at Seton Hill University. He maintains a private specialty practice of orthodontics in Portage, Michigan.

As clear aligner treatments have evolved and been progressively refined in the past 15 years, more advanced applications and increasingly complex malocclusions have been addressed.1-4 In addition, there has been more interest in tackling some of the specific limitations of moving teeth with plastic.5-7 Obviously, the progress of orthodontic treatment with traditional wires and braces has been advanced throughout the past century, but the techniques associated with a sequence of aligners are relatively recent phenomena. Orthodontists with the most experience and enthusiasm in using aligners have worked diligently to improve the concept through better understanding of the limitations involved in more advanced treatment planning, especially when using adjuncts to enhance the associated biomechanics. 4,8-13 The Clear Collection of instruments from Hu-Friedy (Chicago, Illinois, at www.hufriedy.com) was developed with that aim in mind; namely, to help to increase the utility of aligners and expand the scope of appropriate applications (Figure 1). 13

“Innovation is taking two things that already exist and putting them together in a new way.” – Tom Freston

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Figure 1: Hu-Friedy’s Clear Collection of instruments designed to enhance clear aligner treatment (Images courtesy of Hu-Friedy Mfg. Co., LLC, Chicago, Illinois).

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CLINICAL

Figures 2a-2d: The Tear Drop pliers was created to produce a notch in clear aligner plastic to facilitate the application of orthodontic elastics.

Adding intra- and intermaxillary forces The Clear Collection instruments have streamlined and standardized some procedures that orthodontists had already been providing, while opening up more options for other methods to accentuate or refine treatment. In the past, attempting to add intermaxillary elastics for correction of Class IIs, IIIs, or midlines was problematic. Some were cutting notches in plastic trays using scissors or nail clippers10 or attempting to adhere buttons to the trays — all unwieldy endeavors.

The Tear Drop There are occasions when orthodontic elastics are needed to assist with specific tooth movements or growth modification when using aligners. For instance, it may be beneficial to add elastic hooks or bonded buttons in different locations along the arch form on either the buccal or lingual. It would be beneficial to incorporate an elastic hook that cannot be dislodged from the aligner and that only requires a simple

one-step squeeze of a pair of pliers to create. Most importantly, a hook that actually holds the elastic in place on the aligner. The Tear Drop pliers (Figure 2) is an instrument created for the purpose of adding a notch or hook at the gingival margin of clear aligners. A standardized notch is easily cut in a single step, creating a teardrop-shaped “reservoir” to hold the elastic on the tray (Figure 3), thereby making it easier for the patients to seat their aligner and connect their elastics. In this manner, the patient is not fumbling with elastics, attempting to hook them in two locations since the elastic accompanies the aligner as it is seated over the teeth. Teardrop notches should be cut at an angle to resist the line of force of elastics that are being employed (e.g., the notch is angled anteriorly at the mesial of the upper cuspid for Class II elastics; Figure 3). These hooks can be added anywhere along the clear aligner arch at the gingival margin on either the facial or lingual, whenever elastic forces need to be applied.

Figures 3a-3b: Teardrop-shaped hooks retain elastics when aligners are seated, making the addition of “rubber bands” easier for patients to manipulate. Notches are made at an angle to resist forces applied by the elastics. VOL. 11, NO. 2 INTERNATIONAL DENTISTRY – AUSTRALASIAN EDITION 7

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BOWMAN

Figures 4a-4b: The Hole Punch pliers was created to produce a half-moon cutout to permit the addition of bonded buttons or brackets.

Figures 5a-5b: A variety of methods to connect orthodontic elastics can be added to clear aligners using the Hole Punch and the Tear Drop instruments. 5a. Class I intramaxillary elastics connected from teardrop hook to a miniscrew (i.e., to support molar distalization) plus Class II intermaxillary elastics from teardrop notch to bonded button. 5b. Intermaxillary elastics hooked to bonded buttons to assist with seating of teeth into aligners and improve occlusion.

The Hole Punch The Hole Punch (Figure 4) is used to cut a half-moon shaped hole at the gingival margin of aligners. These half-circle cuts permit the addition of bonded buttons, bonded orthodontic tubes or brackets with associated hooks, or are simply used to relieve impingement of plastic on soft tissue. The Hole Punch can be used to produce cuts on either the facial or lingual of any tooth, anywhere along the aligners, whenever needed. Buttons bonded to teeth, rather than to the trays, do not cause dislodgement of the aligner. During the progress of some patients’ treatments (after a series of aligners has already been fabricated and delivered), an orthodontist may wish to add elastics. Bonded buttons can be added to hook up Class II or III intermaxillary elastics, bite-seating elastics, Class I intramaxillary elastics to miniscrews (Figure 5), or elastomeric chain connected to buttons to correct dental rotations. The combination of buttons on molars (plastic relieved using the Hole Punch) along with elastic hooks cut into the plastic at the cuspids (using the Tear

Drop) is a common method of employing orthodontic elastics. In other instances, aligners will occasionally impinge upon gingival tissues and cause gingival pain or inflammation. The Hole Punch can be used to clear the impingement of plastic in each of a series of aligners. A common location for that type of irritation is at the incisive papilla, behind the maxillary central incisors (Figure 6). Nipping along the gingival margin of a tray with the Hole Punch is also an option to relieve marginal gingival impingement on either the buccal or lingual.

Bootstrap mechanics If certain teeth are not “tracking” or are lagging13 behind (i.e., not fitting into the tray; Figure 7) Aligner Chewies™ are employed (Chewies™ Aligner Tray Seaters, Dentsply Raintree Essix, York, Pennsylvania). Patients are asked to hold the Chewie between the teeth in question and squeeze 10-15 seconds, release, and repeat for 5 minutes, 2-3 times per

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BOWMAN

Figures 6a-6d: The Hole Punch pliers can be used to relieve plastic impingement of gingival tissues anywhere along the aligners (e.g., incisive papilla irritation).

day8,13 (Figure 8). In addition, Chewies are routinely used for the first few days when patients switch to a new pair of aligners to help them seat more completely. Another option is to add elastics to forcibly erupt the teeth into the aligner tray.13,14 There are several methods to generate so-called “bootstrap mechanics” (Figure 9):13 1. An orthodontic elastic is stretched over the plastic aligner to connect to a combination of bonded buttons on both lingual and buccal of the tooth. 2. A bonded button is placed on the lingual of the tooth (plastic cleared with the Hole Punch). The Tear Drop notches are cut into the tray at the gingival embrasure spaces in the buccal plastic on both the mesial and distal of the problematic tooth, and an elastic hooked from the buccal notches and stretched over the aligner tray to the button to produce an extrusive force.13 The Tear Drop and/or Hole Punch cuts are made in each tray in the series of aligners prior to their being delivered to the patient. This concept is also useful when the extrusion of a tooth is needed for restorative purposes. Other biomechanics that benefit from the application of elastic forces to aligner trays include the correction of severe rotations, posterior or anterior intrusion mechanics for open bites,11,12 and forces to control anchorage during molar distalization or en masse movements when employing miniscrews (Figure 5).13 Cutting notches and relieving the

Figure 7: Aligner “lag” or lost tracking is most often characterized as an “air gap” between the incisal or occlusal of teeth and the plastic, indicating teeth are not following the prescribed tooth movement.13

plastic to add buttons or brackets facilitate the application of these innovative mechanics. It is important to remember that indiscriminate alteration of the integrity of clear aligners may reduce their structural strength or may impair the intended biomechanics programmed into an aligner. The instruments in the Clear Collection help the orthodontist to better customize clear aligner treatments, enhance their desired biomechanics, and streamline the addition of adjunctive forces during the course of a series of aligners. For information on the use and applications of the Clear Collection, instructional videos are available on YouTube at https://www.youtube.com/ watch?v=hrs2VfnImLY.

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BOWMAN

Figures 8a-8b: Aligner Chewies are held tightly been specific “lagging” teeth for 10-15 seconds. This process is repeated for 5 minutes, 2-3 times daily, especially when changing to a new pair of aligner trays.

Figures 9a-9c: Bootstrap mechanics13 to forcibly erupt a “lagging” tooth using orthodontic elastics (9a-9b). The Hole Punch is employed to clear aligner plastic to permit the addition of bonded buttons. The Tear Drop is used to cut notches in mesial and distal embrasures (9c-9f).

Figures 9d-9h: The Tear Drop is used to cut notches in mesial and distal embrasures (9c-9f). Orthodontic elastics are stretched from the button to the teardrop notches or to another button on the opposite side of the tooth (9g-9h).

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References 1. Clements KM, Bollen AM, Huang G, King G, Hujoel P, Ma T. Activation time and material stiffness of sequential removable orthodontic appliances. Part 2: Dental improvements. Am J Orthod Dentofacial Orthop. 2003;124(5):502-508. 2. Djeu G, Shelton C, Maganzini A. Outcome assessment of Invisalign and traditional orthodontic treatment compared with the American Board of Orthodontics objective grading system. Am J Orthod Dentofacial Orthop. 2005;128(3):292-298. 3. Phan X, Ling PH. Clinical limitations of Invisalign. J Can Dent Assoc. 2007;73(3):263-266. 4. Tuncay O. The Invisalign System. London: Quintessence Publishing; 2007. 5. Kravitz ND, Kusnoto B, BeGole E, Obrez A, Agran B. How well does Invisalign work? A prospective clinical study evaluating the efficacy of tooth movement with Invisalign. Am J Orthod Dentofacial Orthop. 2009;135(1):27-35. 6. Krieger E, Seiferth J, Marinello I, Jung BA, Wriedt S, Jacobs C, Wehrbein H. InvisalignÂŽ treatment in the anterior region: were the predicted tooth movements achieved? J Orofac Orthop. 2012;73(5):365-376. 7. Chisari JR, McGorray SP, Nair M, Wheeler TT. Variables affecting orthodontic tooth movement with clear aligners. Am J Orthod Dentofacial Orthop. 2014;145(4 suppl):S82-91. 8. Tuncay O. Clinical Reports & Techniques. 2005;6(2):1.

9. Daher S. Techniques for Class II correction with Invisalign and elastics. Align Technology, Inc. Web site. Published 2013. Accessed April 11, 2015]. https://s3.amazonaws.com/learninvisalign/docs/ 06840000000GHgmAAG.pdf 10. Paquette D. Temporary Anchorage Devices in Combination with Aligners 2009. Invisalign Web site. http://www.aligntechinstitute. com/files/ATEArchive/pdf/ate_110609.pdf 11. Boyd R. How successful is Invisalign for treatment of anterior open bite and deep overbite? Presented at: American Association of Orthodontists Annual Session; May 5, 2013; Philadelphia, PA. https://www.aaoinfo.org /system/files/media/documents/Boyd,%20Robert%20-%20Treatment%20of%20Deep%20 and%20Open%20bite%20with%20Clear%20Aligners.pdf 12. Dayan, W. Techniques for Posterior Intrusion with Invisalign to Correct Anterior Open Bites. Techniques White Paper 2010. http://www.cityortho.ca/Portals/0/ City%20Ortho-%20 Open%20Bite%20Blog.pdf. 13. Bowman SJ, Celenza F, Sparanga J, Papadopoulos MA, Ojima K, Lin J. Creative adjuncts for clear aligners, Part 1: Class II treatment. J Clin Orthod. 2015;49(2):83-94. 14. Giancotti A, Ronchin M. Pre-restorative treatment with the Invisalign system. J Clin Orthod. 2006;40(11):679-682. Reprinted with permission by Orthodontic practice Volume 6 Number 3

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CASE REPORT

Supernumerary teeth: diagnosis and treatment Javier Martínez Osorio,1 Sebastiana Arroyo Boté2

Abstract We report the case of a 17-year-old patient who came into the clinic because she had noticed a colour change to the maxillary left central incisor (tooth #21) of 48-hour duration. During clinical examination, tooth #21 appeared darker than the rest of the teeth. After performing a complete exploration and obtaining no response to vitality tests, a pulp necrosis of tooth #21 was diagnosed. Differential diagnosis began with the completion of the medical record. The patient had received orthodontic treatment and a supernumerary tooth in the anterior region of the maxilla had been extracted. The patient did not recall having suffered injuries or trauma in the incisal region. A dental panoramic tomogram was obtained, and a high-density area was observed at the apical level in the area of tooth #21. A 3-D computed tomography (CT) scan was then obtained, and it showed the presence of a supernumerary tooth in the periapical region of tooth #21, palatally located and oriented upwards. Necrosis by compression of the neurovascular pedicle of tooth #21 due to the expansion of the erupting follicle of the supernumerary tooth was diagnosed. Pulpectomy and surgical removal of the supernumerary tooth were performed. During surgical removal of the supernumerary tooth, the neurovascular pedicle appeared oedematous and congested and was the cause of the tooth pulp necrosis.

Case report

Dr Javier Martínez Osorio g. He has been Associate Professor of Conservative Dentistry and Endodontics at the Faculty of Dentistry at the University of Barcelona since 1996. He maintains a specialist private practice for implant and endodontic treatment in Barcelona.

A 17-year-old patient who had undergone orthodontic treatment four years before came into the clinic because she had noticed a colour change to her maxillary left central incisor lasting for 48 hours. The patient presented with a tooth discoloration (Fig. 1) with slight pain that ceased with a non-steroidal antiinflammatory drug. During the initial visit to her general dentist, vitality tests were performed and a slight response to the tests was detected. After that, the patient was referred to a specialist. When she presented to the endodontist, the tooth had darkened to a grey-brown colour. In addition to that, the tooth no longer responded to pulp vitality tests. During the visit, the endodontist performed periapical radiographs of the area (Fig. 2), and based on this

Dr Sebastiana Arroyo Boté She has been Associate Professor of Conservative Dentistry and Endodontics at the University of Barcelona since 1992. She maintains a specialist private practice for conservative dentistry and endodontic treatment in Barcelona.

Fig. 1

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Fig. 2

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CASE REPORT

Fig. 3

the existence of a supernumerary tooth at the apical level of the incisor growing towards the floor of the nasal cavity was confirmed. The endodontist requested a CT scan to study the position and assess the possibility of surgical extraction. The CT scan showed the position of the supernumerary tooth relative to the roots of the adjacent teeth, confirming growth towards the periapical region of tooth #21, that is,

a 180-degree deviationfrom the correct orientation for eruption in the dental arch. Reconstruction in 3-D showed this phenomenon clearly (Figs. 3–6). Endodontic treatment of tooth #21 was performed, during which the congested pulp was removed and some bleeding was observed. The length of the guttapercha obturation was deliberately longer than required in order to facilitate surgery (Figs. 7–9).

Fig. 4

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OSORIO | BOTÉ

Fig. 5

Fig. 6

Fig. 8

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Fig. 7

Fig. 9

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Fig. 10

Fig. 11

Fig. 12

Fig. 13

Fig. 14

Fig. 15

Surgical treatment was planned and consisted of raising a semilunar flap on the periapical region of tooth #21 and performing a minimum root resection of 2 mm approximately without a bevel, using a size 0.23 round bur with a straight handpiece, to expose the supernumerary tooth’s crown. The crown was sectioned at the coronal middle third and the incisal portion was removed (Fig. 11). A hole was made in what would be the middle and cervical thirds of the supernumerary tooth to force it up (Fig. 12) and make the extraction through the osteotomy created for apicectomy, thereby achieving a complete extraction (Fig. 13) with minimal trauma to bone and the roots of the incisors. The oedematous pedicle that was compressed by the erupting follicle of the supernumerary tooth and caused a lack of blood

Fig. 16

supply to the pulp of the left central incisor can be observed in the image, held by a haemostat (Fig. 14). Afterwards, preparation for retrograde root filling was performed using a Satelec ultrasonic system and the appropriate handpiece for this surgery. Retrograde root filling was performed with SuperEBA (Bosworth), thereby achieving sealing of the canal at apical level (Figs. 15 &16). The flap was closed with three silk sutures (Fig. 17), which were removed after seven days. Supernumerary tooth after extraction can be observed in the picture (Fig. 18). Two months after the intervention, internal whitening was performed to improve the colour of the incisor. The last two images show the clinical appearance (Fig. 19) and a radiograph (Fig. 20) three years post-treatment.

Fig. 17

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Fig. 19

Fig. 18

Fig. 20

Discussion CT scans, which have been widely used in endodontic diagnostics for fractures and fissures, for example, and in implantology, are not yet commonly used in surgical planning to obtain diagnostic and anatomical data. The relevant and detailed information that this imaging technique provides, especially regarding the position of supernumerary teeth, is proof that it should form part of the protocol during surgical planning. The second point of discussion is the pathway used to approach the supernumerary tooth. We could have used a palatal pathway, but the CT scan revealed that the vestibular pathway was less risky, provided greater visibility and better respected the important anatomical structures, such as the adjacent teeth, without injuring them by accident and risking an iatrogenic injury.

Another important point to be observed is the pathophysiological mechanism that resulted in pulp necrosis. We suspected an apical or periapical resorption of tooth #21 because of the expansion of the erupting follicle and secondary osteolysis, which cannot be excluded. In order to eliminate the greatest number of cells involved in the resorptive-destructive process, an apicectomy was performed. Nevertheless, pulp congestion suggested that the most probable pathophysiological mechanism involved was venous stasis of the vascular plexus that enters the incisor, just before apex. The last point of discussion is when these supernumerary teeth should be removed. If possible, the best time for removal is before any pathology signs appear. This requires consideration of the individual case of each patient, and performing clinical and radiographic follow-up of the case in order to determine the right time.

Conclusion The presence of supernumerary teeth in the permanent dentition has a frequency of between 0.1% and 3.8%. Necrosis of the adjacent teeth is one of the possible complications of this phenomenon; therefore, clinicians must consider the possibility of a supernumerary tooth during diagnosis, especially in patients with pulp necrosis without previous traumatic dental pathology. Reprinted with permission by Cone Beam 1_2015

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INTERVIEW

edelweiss VENEERs and OCCLUSIONVDs: A holistic concept for bio-aesthetics and function Claudio Novelli1

In times of growing health awareness, users and patients are increasingly looking for alternative treatment options to conventional, usually invasive, ceramic and crown veneers without wishing to compromise on aesthetics and function. In this interview, Dr Claudio Novelli, Clinical and Scientific Director of edelweiss dentistry, talks about a solution provided by the Austrian company that allows holistic restoration using prefabricated, laser-sintered glass enamel shells in just one appointment.

Edelweiss: Prof. Claudio Novelli, as Clinical and Scientific Director of edelweiss dentistry, you have always been at the forefront of the development of the DIRECT SYSTEM. What led you and your colleagues to the idea of producing and expanding upon prefabricated enamel shells made of composite? Prof. Claudio Novelli: We were well aware that it is an artistic and technical challenge for many users to produce high-quality direct composite veneers using the freehand layering technique. The idea was to simplify this method, yet still produce a precise result without making compromises on material properties. The focus was on a highquality and minimally invasive treatment option for patients with a tight budget. Patients are becoming more critical about aesthetic dental treatments. Quality is a given, so it is the cost that matters. We are not interested in developing dental ceramics that only 5 per cent of the worldâ&#x20AC;&#x2122;s population can afford; rather, we are striving to reach a greater market with our system. Yesterday

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Today

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INTERVIEW

Yesterday

Today

According to the five month splint therapy, 6mm increase of vertical dimension, provided with non-prep edelweiss VENEER's & Occlusion VD's

Owing to their biomechanical similarity to natural dental enamel, prefabricated veneer and occlusion shells offer an ideal alternative to the widespread more rigid and invasive ceramic veneers and crowns currently available. Nowadays, composite resins have taken on a leading role among restoration materials. They offer aesthetic potential, satisfactory durability and lower costs for dentists and patients than the equivalent ceramic restorations. Our patented technique of laser sintering the enamel shells composed of nano-hybrid composite results in highly bio functional and aesthetic glass surface enhancement. Besides easy placement, which can be performed in a single appointment, this is a bio-aesthetic quantum leap for the dentist and patient alike.

The specially developed process for producing veneer and occlusion shells combines the best of both worlds, resulting

in a dynamic sintered core with a high-gloss vitrified surface. The highly filled edelweiss nano-hybrid composite material is moulded under high pressure, laser sintered and processed into wafer-thin prefabricated enamel shells in the form of anatomically optimised veneers and occlusion onlays with 95 percent of glass. The subsequent laser sintering, a kind of fusion or coating process, gives the enamel shells a purely inorganic surface, homogenously sealed, as smooth as ceramic with an outstanding gloss. This surface not only protects against discolouration, but also produces a perfect aesthetic and functional result. The contourable enamel shells for the maxillae and mandible are fabricated in several sizes based on intensive studies of the shape and size of the tooth geometry. Their translucency and layer thickness are comparable to those of natural youthful enamel, thus allowing their universal use in combination with suitable shade-matched composite dentine chromas.

Yesterday

Today

What does the industrial production of these enamel shells entail?

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Yesterday

Today

Could you please explain the term “bio-aesthetics”?

flexibility, which provides for good performance and resistance to cracking even when bonding to dentine. In contrast to ceramics, enamel shells can be adjusted to the existing tooth situation and shape individually directly on the patient or model. This allows the smile design and reconstruction to be freely configured, for instance in the presence of severe bruxism. The wafer-thin enamel shells allow minimally invasive application, in that the tooth is freed of residue and is only minimally roughened. The restored tooth is then prepared using the etch-bond technique and is cemented with highly filled composite material. This produces a biomechanical monoblock, which ensures optimal adhesion and integration in the given tooth situation. Using Ultradent Products’ Peak Universal Bond, this technique even allows for existing metal and ceramic restorations to be veneered. Improved and true-to-life shade matching is guaranteed by the enamel and composite shades included with the system, based on the Natural Layering Concept by Dr Didier Dietschi.

Let’s remove the term “bio” and replace it with “natural”. Natural, of course, means minimally invasive treatments. Restoration and optimisation are carried out while considering and preserving the healthy tooth structure. The function and aesthetics are reconstructed with a composite very similar to the tooth substance—a concept that clearly speaks in favour of non-restorative or additive techniques. In contrast to our method are invasive grinding of healthy teeth and restoration with ceramic crowns without taking natural biomechanics into consideration to obtain a Hollywood smile. This is not in line with the edelweiss dentistry philosophy.

What distinguishes this new application method from ceramics? For the user, it is important to remember that, even if highquality adhesive systems are used, ceramics are mainly supported by enamel and not dentine. The prefabricated enamel shells, however, show very strong bonding and

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Alongside veneers, there are prefabricated occlusal onlays in your system. What new possibilities do they offer?

Owing to the lifelike biomechanical properties of the composite material and therefore also of the veneers, none of the surrounding tooth substance is affected or damaged, which underscores the ethical aspect of this method in contrast to ceramic restorations. By virtue of their flexibility, the enamel shells are also ideally suited for use in the mandible, as the wear of the antagonist second dentition is better, more true to nature than that of ceramic. This makes edelweiss VENEERs and OCCLUSION-VDs the ideal solution for patients with a low budget, especially for young people or for those who practise contact sports.

The translucent OCCLUSION-VD shells represent the anatomical basis for individual or complete reconstructions, as well as for lifting the vertical dimension in the posterior region. Hence, the name OCCLUSION-VD, where VD stands for vertical dimension. Just like optimally correcting glasses can relieve headaches and improve poor posture, OCCLUSION-VDs, functioning as an occlusal splint and adapted according to the patientâ&#x20AC;&#x2122;s individual problems, can influence our entire postural system.

Yesterday

Today

Regio 16, 25 and 26: Implants and gold crown covered with Occlusion VD's

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Yesterday

Today

Changing color and shape and achieving a functional canine guidance with edelweiss VENEER's

Close the diastemas and achieving a functional canine guidance with edelweiss VENEER's

Cover and replace old composite fillings with edelweiss VENEER's

As a result of their natural morphology, the prefabricated OCCLUSION-VDs are very easy to integrate into the existing occlusion. OCCLUSION-VDs help eliminate or prevent the causes of craniomandibular dysfunction. In addition, OCCLUSION-VDs serve to correct inherent malocclusion and deep bites in a minimally invasive way. By the occlusal surfaces being covered, usually in the mandible, the mandible is brought into the correct position in relation to

the maxillae. This makes it possible to attain functioning guidance of anterior teeth and canines by using edelweiss veneers. The combination of edelweiss VENEERs and OCCLUSION-VDs allows for complete rehabilitation and holistic restoration of the dental arch to be undertaken in order to achieve the best possible overall outcome. Individual re-occlusion achieves a new functioning, balanced and smoothly working masticatory apparatus.

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Your system largely supports the direct procedure. How does this work, for instance in achieving a vertical bite increase with OCCLUSION-VDs? Does this require a laboratory? For restorations with edelweiss VENEERs and OCCLUSIONVDs, besides the direct chairside method, a dental laboratory can always be called upon, where fitting can be performed indirectly on an existing plaster model using a semi adjustable articulator. The prefabricated anatomic

enamel shells allow the option of fitting and relining the bite situation in the laboratory, thus optimising the time and cost factors. In fact, in complicated initial situations, articulating the bite in the laboratory is absolutely recommended. Practical use in the respective indication area can be learnt at one of our one-day workshops. Those interested can obtain detailed information on the workshops from all of our trading partners or directly from edelweiss dentistry.

edelweiss workshops in Australia • Adelaide

05.07.2016

• Sydney

06.07.2016

www.henryschein.com.au/eventsandeducation

• Brisbane

11.07.2016

• Perth

12.07.2016

• Melburne 14.07.2016

Explore the step by step videos and quick tips on the edelweiss website and learn how to optimally treat your patients within a short time. www.edelweissdentistry.com/videos

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Should I incorporate a cantilever extension on an implant-supported fixed dental prosthesis (FDP) or not? Johan Hartshorne1 A critical appraisal of a systematic review and meta-analysis: Torrecillas-Martinez L, Monje A, Lin G-H, Suarez F, Ortega-Oller I, Galindo-Moreno P, Wang H-L. (2014) Effect of cantilevers for implant-supported prostheses on marginal bone loss and prosthetic complications: Systematic review and meta-analysis. International Journal of Oral and Maxillofacial Implants. Accepted manuscript, doi: 10.11607/jomi.3660

Summary Systematic review conclusion: Marginal bone loss does not seem to be influenced by the presence of cantilever extensions. Minor technical complications were found when a cantilever was present when compared to the control groups. The lack of scientific evidence does not permit clear conclusions to be drawn. Critical appraisal conclusion: This meta-analysis is characterized by sparse and very low level quality of evidence, and critical methodological errors. The meta-analysis is considered worthless in terms of the focussed clinical question. Available data on the effect of implant-supported FDPs with and without a cantilever extension are scarce suggesting further research on this topic. Implications for clinical practice: Current systematic reviews supports the use of FDPs supported by two or more implants with a short cantilever extension (one tooth either mesial or distal), as an acceptable alternative therapeutic option to avoid procedures that require more advanced surgery (e.g. sinus elevation or bone grafts), for aesthetic reasons, in anatomical compromised locations, or in cases where patients have limited financial means to afford complex treatment. However, until more evidence becomes available, this treatment modality should not be seen as the standard of care that can be generalized to all cases.

Clinical question “In partially edentulous patients restored by implant-supported prostheses with or without cantilever extensions, are there any differences in terms of marginal bone loss and prosthetic complications?”

Review methods Methodology The reviewers conducted the systematic review of the literature according to the PRISMA1 (Preferred Reporting Items for Systematic Review and Meta-analysis) statement.

Johan Hartshorne B.Sc., B.Ch.D., M.Ch.D, M.P.A. Ph.D. (Stell), FFPH.RCP (UK), Visiting Professor, Department of Periodontics and Oral Medicine, University of Pretoria, Pretoria, South Africa.

E-mail: jhartshorne@kanonberg.co.za

Search strategy and study selection Two independent reviewers conducted an electronic literature search of the MEDLINE-Pubmed database for relevant articles from June 2003 to January 2013. In addition, a manual search of implant-related journals from 2010 to 2013 was also performed to ensure a thorough screening of the available literature. The search was restricted to articles in English only. Eligibility and exclusion criteria Prospective human clinical trials studying implant-supported fixed partial prosthesis with cantilevers with at least 12 months loading were eligible for the meta-analysis. The studies had to include the following data: the extension of the cantilever, the type and number of implants supporting the cantilever, location of the implants, and the antagonist (opposing) occlusion, and the biological and prosthetic complications.

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Case reports, systematic reviews, and animal studies were excluded from the meta-analysis. Studies where no cantilever extensions or MBL were reported or where patients underwent any type of bone augmentation at the implant site were also excluded. References in the excluded studies were also checked for studies that fulfilled the inclusion criteria. Outcome measures and data extraction The primary outcomes analysed was the amount of radiographic bone loss around dental implants. The pooled weighted mean (WM) and the 95% confidence interval (CI) of each variable as well as the weighted mean difference (WMD) was calculated and analysed. Random effects metaanalysis of the selected studies was applied to avoid potential bias being caused by methodological differences among studies. Forest plots were produced to graphically represent the data for all included studies using the number of participants investigated as the analysis unit. Funnel plots were also examined to detect publication bias. Studies with more than one treatment arm were combined for statistical analysis. Heterogeneity among studies was assessed with the P value of the chi-square test, and P < .05 represented significant heterogeneity.

Main results A total of 4 articles fulfilled the inclusion criteria for this metaanalysis. Statistical analysis revealed a low heterogeneity among studies (P = 0.60). The weighted mean for the pooled data of the marginal bone loss (MBL) was 0.72 mm 95% CI (0.36 to 1.08). Porcelain fractures was the most common prosthetic complication (39.2%). Abutment screw loosening was relatively low for the cantilever extensions in all the studies analysed. Only one study reported prosthesis decementation in 3 of 59 FDPâ&#x20AC;&#x2122;s.2

Conclusion Marginal bone loss does not seem to be influenced by the presence of cantilever extensions. Minor technical complications were found when a cantilever was present when compared to the control groups. The lack of scientific evidence does not permit clear conclusions to be drawn. The authors reported no conflict of interest with respect to the authorship and/or publication of this review.

Commentary Background and importance Unilateral implant-supported FDPs with cantilever extensions are frequently used to expand therapeutic options where there is insufficient bone or compromised anatomical locations, a need exists to avoid implantation and bone grafting, and to save treatment time and costs.

Finite-element analysis show that cantilevered prostheses can produce enhanced stress concentrations at the distal bone/implant interface facing the cantilever extension potentially causing biological (e.g. bone loss) and technical (screw loosening, porcelain fracture, or implant fracture) problems. 3 A number of recent systematic reviews have reported on survival rates and the biological, technical and mechanical complications of implant-supported FDPs with cantilevers compared those without cantilevers.4, 5, 6, 7 Current evidence indicate that the incorporation of cantilever extensions into implant-supported FDPs, is a valid and reliable treatment alternative for replacing missing teeth in partially edentulous patients, this treatment modality has a high survival rate, does not have any clinically significant effects on the peri-implant MBL at the implant next to the cantilever, and may be associated with a higher incidence of minor technical complications (screw loosening and porcelain fracture).5, 6, 7 However, biological and technical complication was observed more frequently after 10 years.4 In addition, there is also limited evidence to support the use of FDP with a cantilever extension supported by one implant.7 To date, however, controlled clinical trials on implantsupported FPDs with and without cantilever extensions are scarce, therefore survival and complication rates should be interpreted with caution. Are the results valid? The studies included in the review consisted of one controlled clinical trial8 and three prospective observational studies (no controls without cantilevers).2,9,10 Overall, the level of evidence is of a very low quality and only one study8 fulfilled the requirement of answering the clinical question. The methodological rigor of the review is questionable due to various limitations such as: inadequate searching of bibliographic databases, grey literature was not search and no inquiry was conducted regarding unpublished studies. Furthermore the study was limited to English language only. Therefore based on these observations there is a good probability that some studies could have been omitted, such as the controlled clinical control trial by HĂ¤lg and co-workers11, and the case-control study by Kim and co-workers12 (Manuscript accepted 18 November 2012, Article first published online 2 January 2013). The eligibility criteria used to select article for inclusion or exclusion was not clearly defined apriori and very vague. The authors did not report whether the individual studies were evaluated for methodological quality. Considering abovementioned there are various potential sources of bias that has not been addressed. Based on the limitations and weaknesses presented by review study, the validity of the results was inadequate for the type of question asked.

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What were the key findings? The authors of the review made a critical error by using the study by Palmer and co-workers10 in the meta-analysis of the average marginal bone loss around implant-supported restorations with and without cantilevers. The study by Palmer did not include a control group without cantilevers in their study and is basically an observational study of implantsupported prostheses with cantilever extensions. The authors of the review erroneously used average marginal bone loss values measured on the opposite side of the implant surface facing the cantilever extension. This error rendered the metaanalysis thus worthless in terms of the focussed question.

Clinical resolution The study question is relevant and important to clinical practice. However, the meta-analysis was worthless and did not make any contribution towards current available knowledge on this topic. Well-designed, assessed and reported randomised clinical trials are required to study the effects of: various prosthetic designs (e.g. distal or mesial) cantilever extensions, the number of implants and implant connection supporting FDPs with cantilever extensions, and occlusal concepts on the incidence of biological and technical complications.

Disclosure Dr Johan Hartshorne is trained in clinical epidemiology, biostatistics, research methodology and critical appraisal of research evidence. This critical appraisal is not intended to, and do not, express, imply or summarize standards of care, but rather provide a concise reference point for dentists to aid in understanding and applying research evidence from referenced early view or pre-published articles in top ranking scientific publications and to facilitate clinically sound decisions as guided by their clinical judgement and by patient needs.

References 1. Liberati A, Altman DG, Tetzlaff J, Mulrow C, Gotzsche PC, Ioannidis JP, Clarke M, Devereaux PJ, Kleijnen J, Moher D. The PRISMA statement for reporting systematic reviews and meta-analysis of studies that evaluate healthcare interventions: explanation and elaboration. Brit Med J 2009; 339: b2700. 2. Romeo E, Tomasi C, Finini I, Casentini P, Lops D. Implant-supported fixed cantilever prosthesis in partially edentulous jaw: a cohort prospective study. Clin Oral Impl

Res 2009; 20: 1278-1285. 3. Rubo JH, Capello Souza EA, Finite-element analysis of stress on dental implant prosthesis. Clin Implant Dent Relat Res 2010; 12: 105-113. 4. Pjetersson BE, Tan K, Lang NP, Bragger U, Egger M, Zwalen M. A systematic review of the survival and complication rates of fixed partial dentures (FPDs) after an observation period of at least 5 years. IV. Cantilever or extension FPDs. Clin Oral Impl Res 2004; 15: 667-676. 5. Aglietta M, Siciliano VI, Zwalen M, Brägger U, Pjetursson BE, Lang NP, Salvi GE. A systematic review of the survival and complication rates of implant supported fixed dental prostheses with cantilever extensions after an observation period of at least 5 years . Clin Oral Impl Res 2009; 20: 441-451. 6. Zurdo J, Romão C, Wennström JL. Survival and complication rates of implant-supported fixed partial dentures with cantilevers : a systematic review. Clin Oral Impl Res 2009; 20 (Suppl. 4): 59-66. 7. Romeo E, Storelli S. Systematic review of the survival rate and the biological, technical, and aesthetic complications of fixed dental prostheses with cantilevers on implants reported in longitudinal studies with a mean of 5 years follow-up. Clin Oral Impl Res 2012; 23(Suppl. 6): 3949. 8. Wennström J, Zurdo J, Karlsson S, Ekestubbe A, Gröndahl K, Lindhe J. Bone level change at implantsupported fixed partial dentures with and without cantilever extension after 5 years in function. J Clin Periodontol 2004; 31: 1077-1083. 9. Romeo E, Lops D, Murgatti E, Ghisolfi M, Chiapasco M, Vogel G. Implant-supported fixed cantilever prostheses in partially edentulous arches. A seven-year prospective study. Clin Oral Impl Res 2003; 14: 303-311. 10. Palmer RM, Howe LC, Palmer PJ, Wilson R. A prospective clinical trial of single Astra Tech 4.0 or 5.0 diameter implants used to support two-unit cantilever bridges: results after 3 years. Res 2012; 23: 35-40. 11. Hälg GA, Schmid J, Hämmerle CHF. Bone level changes at implants supporting crowns or fixed partial dentures with or without cantilevers. Clin Oral Impl Res 2008; 19: 983-990. 12. Kim, P, Ivanovski S, Latcham N, Mattheos N. The impact of cantilevers on biological and technical success outcomes of implant-supported fixed partial dentures. A retrospective cohort study. Clin Oral Impl Res 2014; 25: 175-184.

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Digital possibilities for making implant prosthetics Joannis Katsoulis1

Introduction In contemporary dental medicine, computers and implants are closely linked. By dealing with this topic, the question arises whether one can speak about a(n) (r)evolution in planning and manufacturing of tooth- and implant-supported reconstructions in the field of implant prosthetics. Dental prosthetics are concerned with the restoration of lost teeth and tooth-bearing tissues in the oral cavity. Loss of teeth and edentulism are quite frequent in old age and often the main reasons to visit a dentist. Hence, dental implants have become important means of therapy, whereby computer-assisted procedures play an increasing role in the daily routine of the dental practice. Thus, it is no contradiction to use modern computer technology and new materials equally for young and old people. The continuous advancement of specialised fields in radiological imaging, manufacturing methods in the engineering industry und dental implantology have extended the possibilities of decision making, planning and surgical as well as prosthetic realisation of a therapeutic plan. Actually, this proceeding of dental medicine only has been made possible by bringing together these formerly independent disciplines, which basically depend on the increased performance of digital data processors.

PD Dr med. dent. Joannis Katsoulis, MAS Department of Reconstructive Dentistry and Gerodontology School of Dental Medicine University of Bern Freiburgstrasse 7 3010 Bern Switzerland joannis.katsoulis@zmk.unibe.ch

Figure 1: Virtual 3-D implant-planning based on volume tomography.

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Figure 3: Full-ceramic reconstructions.

Figure 2: Digital design of CAD/CAM-FDP framework.

Revolution or evolution? Despite these developments, many colleagues do not consider a computer a helping advice in their daily routine. Any digitalisation of a certain practice area needs a modification and adaption of the whole team’s workflow, depending on the scope of digitalisation. This requires a large effort of all employees involved, the willingness to learn from earlier mistakes and to keep pace with the progressing digital technologies. One thing is certain: Innovations in dental medicine do occur more often and faster nowadays. Therefore, evolution or revolution does not depend on the given digital possibilities but rather on the individual experience and know-how. In dental medicine, computer technology is no more a real technological revolution. Virtual implant-planning based on volume tomography has facilitated the decision making and information for a patient for quite some time now (Fig. 1). Computer-assisted implant placing occurs with high precision in partially or fully edentulous patients.1 Here, the so-called backward planning ensures a high level of predictability of the surgical and prosthetic result. The surgical realisation of the 3-D planning with stereolithographic splints is an important advancement in complex cases and can contribute to less invasive and rapid proceedings in selected cases. By this, one can precisely determine whether a completely “flapless” procedure is possible for single or all planned implants in the jaw and which aug - mentative technique is indicated.2

Especially for older patients with relatively more risks when implanting, a well-planned, minimally-invasive proceeding with a shortened operation time is of advantage.3, 4 Additionally, the digitalised anatomical and prosthetic conditions can be analysed virtually and with the help of clearly-formulated criteria contribute to the decision making in case of either fixed or removable implant-borne reconstructions.5 It has turned out that the proportion of bone in the upper jaw is clinically often over - estimated.6 According to the characteristics of an atrophy of the alveolar ridge, the prostheticoriented planning will control the implant positioning and type of reconstruction of the operation virtually in advance.

CAD/CAM technologies in implant prosthetics Closely connected to computer-assisted implant planning is the CAD/CAM technology (ComputerAided Designing/Computer-Assisted Manufacturing), which has significantly changed the dental medicine in the course of the past twenty years.7 The more parallel dental implants can be planned and clinically placed, the easier and more stable the design (Fig. 2) of CAD/CAM frameworks/FDPs (Fixed Dental Prostheses) and bars made of titanium or zirconia can be kept. These materials are also characterised by improved technical and biological features. Consequently, technical and biological complications are to be expected less often.8, 9 Depending on the connection type of implant systems, also full-ceramic reconstructions can be screwed together directly on the implant’s level (Fig. 3). The fitting accuracy of implant-borne CAD/CAM-titanium and -zirconia reconstructions are significantly higher than the

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Figure 4 and 5: Fitting accuracy below 50 μm is possible for CAD/CAM full-arch reconstructions providing passive fit with minimal stress.

conventionally produced bridges with cast alloys.10 By now, most of the major manufacturers offer their own CAD/CAM systems and have centralised production facilities for manufacture of frameworks and bridges at their disposal. Thus, a fitting accuracy below 50 μm (Fig. 4 & 5) seems routinely possible for full-arch reconstructions with the required care and know-how of the production process.11-13 The CAD/CAM production is specific for metals like titanium and ceramics, as for example zirconia. For milling with CNC-machines, especially suited milling cutters are used. After the milling of zirconia in the overdimensioned green-/whitebody, the final crystallisation (sintering and HIP) of the work piece is made. Despite of automated and mechanical processes, the CAM step requires the experience

of specialised engineers who are able to oversee the processes and step in if problems occur. The current development efforts and advancements take place in the area of software possi - bilities and the connection of individual digital sub areas. Thereby, a universal data format (STL) enables the forwarding of data by intra- or extraoral scanners via CAD- and CAM software. However, it probably might take some time until the various providers will open their systems completely and thus enable users to freely choose between the digital work steps. Editorial note: A list of references is available from the publisher. Reprinted with permission by CAD/CAM 1_2015

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Tooth whitening: the last 25 years Linda Greenwall1 The introduction of contemporary tooth whitening techniques was launched in 1989 with a research paper called ‘Nightguard vital bleaching’. The authors, Van Haywood and Harald Heymann, described the use of a bleaching tray as a vehicle to place the whitening gel into the mouth for better retention and to give better long lasting and predictable results. Further research by the authors showed the effectiveness, efficacy, predictability, longevity and reduction in side effects. It has now been 27 years since that paper was published and this article will review how, in just a quarter of a century, tooth whitening has become a valued treatment service for patients with a vast body of scientific literature behind it. Millions of people around the world have benefitted from the use of the tooth whitening materials and techniques over the last 25 years and its popularity continues to grow (Greenwall, 2001). Although tooth whitening techniques were popular in the 1880s – using strong concentrations of hydrogen peroxide and a bleaching lamp – modern techniques focus on the use of a bleaching tray and applying products in the tray at home. It was Bill Klausmier, an American orthodontist, who started using the technique in 1968 to help reduce the swelling on the gingivae post-orthodontic treatment. He advised his patients to use peroxyl mouthwash into the retainer to reduce the gingival hyperplasia (Haywood, 1991a). At the six-month recalls he noted that not only were the gingivae of the patient significantly better, but the teeth were also whiter. This chance finding, similar to the invention of penicillin, has allowed many patients to benefit from these techniques. After using this technique for 40 years, he reported that nobody needed a root canal treatment, nor broke nor damaged a tooth following the use of peroxide in the tray. He advised his colleagues in a local study group to use this technique and subsequently passed it onto Dr Van Haywood who began research on the technique.

Early research Dr Linda Greenwall, BDS MSc MGDS RCS MRD RCS FFGDP(UK), is a specialist in prosthodontics and restorative dentistry, London, UK. An international authority on tooth whitening, she is the founder and current chair of the British Dental Bleaching Society. Dr Greenwall is editor-in-chief of the journal Aesthetic Dentistry Today, and has written several textbooks, including the recently updated second edition of Bleaching Techniques in Restorative Dentistry.

Early research focused on whether the whitening products were safe and effective. Professor Yiming Li from Loma Linda University has devoted the last 20 years of his research life investigating the safety of hydrogen peroxide. He has concluded that it is safe to use as a whitening agent in the oral cavity, as long as the products used are supervised and monitored by the dentist and the dental team (Li, Greenwall, 2013). There was an explosion of research conducted on whitening in the early 1990s, and there are now thousands of articles published on all aspects of whitening. There was extensive research conducted on the side effect of sensitivity, which occurs in up to 85% of patients. Research was conducted as to how and why the sensitivity occurred and how best to treat it. It was discovered that whitening gel penetrates the tooth within five to 15 minutes of application. It is therefore essential to assess the pulps of all the teeth to make sure they are healthy prior to undertaking any whitening procedure. If whitening was to be undertaken in the presence of a non-vital area, the area will flare up and need a root canal treatment. It is best to plan a root canal treatment to be undertaken prior to starting any whitening treatment.

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Figure 1: An advanced whitening case with a diagnosis of fluorosis. The patient had direct composite bondings placed over the upper central incisor teeth to mask the discolouration, which were removed prior to whitening. Home bleaching was undertaken using 10% carbamide peroxide in a bleaching tray.

Figure 2: Result after whitening with carbamide peroxide for eight to 10 weeks.

Methods of whitening

intended purpose of tooth whitening. The products should not be directly freely available to the consumer. Products may only be purchased through a dental practice and tooth whitening products containing or releasing between 0.1% and six per cent hydrogen peroxide may only be sold to dental practitioners. For each cycle of use, the first use must be carried out by a dental practitioner or under their direct supervision if an equivalent level of safety is ensured. After the first cycle of use, the dental practitioner may give the product to the consumer to complete the cycle of use. Concentrations exceeding six per cent of hydrogen peroxide remain prohibited unless wholly for the purpose of the treatment or prevention of disease. It is essential that dentists abide by the legislation, as Trading Standards can prosecute them if they use higher than six per cent hydrogen peroxide on a patient or if they intend to supply a patient with whitening gel stronger than six per cent hydrogen peroxide.

There are two basic techniques for home bleaching, depending on the products: • Night-time use, using a carbamide peroxide material • Day-time use, using a hydrogen peroxide only material.

How have things changed? Changes in the whitening legislation were introduced in 2011. The Cosmetic Products (Safety) (Amendment) Regulations 2012 (implementing Directive 2011/84/EU, which amends Directive 76/768/EEC) came into force on 31 October 2012. The legislation specifies that products containing or releasing between 0.1% and six per cent hydrogen peroxide cannot be used on any person under the age of 18, except where such use is intended wholly for the purpose of treating or preventing disease. Products containing or releasing less than 0.1% of hydrogen peroxide, including mouth rinse, toothpaste and tooth whitening or bleaching products, are safe and will continue to be freely available on the market. Tooth whitening or bleaching products containing or releasing between 0.1% and six per cent of hydrogen peroxide may be used provided an appropriate clinical examination is carried out in order to ensure that there are no risk factors and any other oral pathology is ruled out. The exposure to the whitening products should be limited to ensure that they are only used as intended in terms of frequency and duration of application. Whitening products should be clearly labelled for their

Bleaching single dark teeth The treatment options for both vital and non-vital teeth have changed over the last 25 years with the introduction of whitening techniques. These days a sectional whitening tray can be used to whiten a single dark tooth, whether vital or non-vital. It is essential to whiten the dark tooth first in order to establish the whitening potential and possibility. If the whitening of the dark tooth doesn’t start first, the rest of the teeth will whiten quicker and the contrast of the dark tooth will look worse.

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Table 1: Some of the changes that have occurred in tooth whitening over the last 25 years How has tooth whitening changed over time? Patient factors

Material factors

Technique factors

Expectations increased

Two-week tray use now

Take home gels now fifth generation formulation

Seeking whiter teeth

Extended tray use

Introduction of soothers, potassium nitrate and fluoride and acp

Philosophy of perfection

Changes in tray designs

Concentrations of materials have changed

More difficult discolourations

Used with aligners

Power gels have changed

No age restrictions for older age patients

Therapeutic uses now introduced

Is light essential?

No age limit for under 18

Whitening strips introduced

Lights/no light?

Whitening maintenance

Heat/no heat?

Whitening for life

Lasers

Bleachorexia/bleachoholic

Ozone

Vital single dark teeth When the patient receives mild trauma to an anterior tooth, the tooth tries to repair and heal itself by laying down extra secondary and tertiary dentine in the pulp chamber. The trauma results in bleeding into the pulp chamber and pulp canal. The blood products reorganise and break down into iron. The discolouration, which is a result of the bleeding and the formation of secondary and tertiary dentine, can be detected when the tooth is a different colour to its neighbour by about one or two shades only. In the past it was thought that these teeth, which are diagnosed as having calcific metamorphosis (Haywood, 2010), need to have root canal treatments. However, this is not true â&#x20AC;&#x201C; they need only be whitened.

Non-vital teeth The techniques for non-vital bleaching have also evolved with the banning of sodium perborate by the scientific committee in Europe, which was concerned about the fetotoxic and cytotoxic effects. The standard technique, which was called the Walking Bleach technique and first described by Nutting and Poe in 1965, was advocated by using sodium perborate mixed with 35% hydrogen peroxide. The two products together act synergistically and create

the equivalent of 50% hydrogen peroxide, which is too caustic for a root canal considering that it may be affected by trauma previously. High concentrations of hydrogen peroxide have been banned in Europe and it may only be possible to use six per cent hydrogen peroxide sealed into a root canal. In addition, the strong concentrations of hydrogen peroxide in combination with previous trauma to the tooth may result in cervical resorption (Cvek, Lindwall, 1985; Hierthersay 1999), which has been extensively described in the literature. There are new modifications for this treatment, which involve the use of a bleaching tray and a segmental bleaching tray. These days, 16% carbamide peroxide is sealed into the root canal and the patient uses the bleaching tray to whiten the external surface of the tooth, meaning that the tooth is effectively whitened from the inside and the outside with the same technique. Dr William Liebenberg described a modification in 1997, in which he advocated leaving the access cavity of the nonvital tooth open so that the patient could apply the whitening syringe into the access cavity every two hours thereby whitening the tooth over the course of the weekend. The patient was to return at the end of the weekend and the access cavity disinfected and cleaned and the pulp chamber restored with glass ionomer.

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Figure 3: This patient had a basic inherent grey shade to his teeth.

Figure 4: The result after whitening for six weeks with home bleaching trays for six weeks using 10% carbamide peroxide whitening gel.

The future: whitening varnish

possible and it is the responsibility of the dentist to explain the realistic expectations and outcomes they may expect. The dentist should be able to explain to the patient what they can, and cannot, expect to happen in terms of a uniform whiteness. There is also the time factor associated with whitening – the darker the tooth, the longer it will take to whiten. Not all teeth can be whitened within two weeks. Darker and more difficult discolourations can be treated with home bleaching at 10% carbamide peroxide, but the treatment times are extended to between eight and 10 weeks. Patients who have tetracycline-stained teeth will be able to achieve whitening but the treatment times are much longer. Severe discolourations can extend whitening treatment to up to 12 months. There is no age restriction for older age patients to be able to whiten their teeth (Kelleher et al, 2011) and it is a factor of anatomy as to how quick the gel can penetrate into the tooth to permit whitening to take place. Older teeth are more heavily compacted with secondary dentine and so their teeth will take longer to whiten. Younger teeth will lighten quicker as their anatomy demonstrate open odontoblastic process and enamel is young. Despite the fact that there are larger pulp canals and pulp chambers, young patients who undertake whitening do not demonstrate more sensitivity than older patients (Greenwall, 2009).

There are exciting new developments in tooth whitening products with the introduction of whitening varnish. The tooth is coated with a varnish that contains six per cent hydrogen peroxide. This hydrophilic (moisture-loving) varnish adheres well to the tooth, delivering the active agent directly into the enamel and dentine. A second, sealant layer dries onto the tooth and locks the hydrogen peroxide layer in place. This varnish layer is hydrophobic (water repellent) and the two varnish layers are immiscible (do not mix) during application. The varnish is left on the teeth for half and hour per day and then brushed off with a toothbrush. There are also new developments with enzymatic bleaching where two products are mixed together to activate and speed up the process of whitening using a three per cent carbamide peroxide gel in combination with lactoperoxidase.

Increased patient expectation With the introduction of new whitening treatments, patients are demanding whiter and whiter teeth. Patient expectations have increased – they now expect to have white teeth instantly, which are perfect in shape and size. They also expect that dentists will be able to achieve a whiter smile for them instantly. Patients are seeking whiter teeth and, for some, this whiteness has reached extreme levels. There is a philosophy of perfection that has crept into popular culture and there is a certain fashion trend associated with whitening. The media shows whitening as a must-have item and the advent of the extreme makeover shows has led to unrealistic expectations. A perfect smile with perfectly white teeth is not always

Home bleaching Research studies have demonstrated that, for a basic whitening case using the original protocol of Professor Van Haywood (Haywood 1991a,b,c), the total treatment time is about four to six weeks. Normally, the upper teeth are

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Table 2: A selection of whitening materials containing carbamide peroxide for use in a bleaching tray Carbamide peroxide whitening products 10%

15%

16%

Polanight (SDI)

Opalescence PF (Ultradent)

Polanight (SDI)

Opalescence PF (Ultradent)

Illuminé (Dentsply)

Opalescence PF

Perfect Bleach (Voco)

Nitewhite (Philips)

Zaris White & Brite (3M)

Evolution Enlighten

Evolution (Enlighten)

Zaris White & Brite (3M)

Illuminé (Dentsply)

Evolution (Enlighten)

White Dental Beauty (Optident)

Perfect Bleach (Voco) White Dental Beauty (Optident)

whitened first for a period of at least two weeks and then reassessed. Then upper and lower whitening may take place together for one week and thereafter the lower teeth are whitening for a further two weeks. The upper teeth may take two to three weeks to whiten on consecutive nights. The upper teeth are whitened first as they whiten quicker and normally experience less side effects and sensitivity, the patient has a colour comparison when only the upper teeth are whitened first. The lower teeth may take at least three weeks to whiten each evening. The lower teeth experience more sensitivity due to the tray contact with the lower premolar teeth and the cervical recession present on some teeth. There is thought to be washout with the salivary duct so whitening takes longer on the lower teeth.

Whitening maintenance If the protocol is followed precisely, research has shown that whitening can last up to 17 years. However, some patents like to top-up their whitening after three years. It is not necessary to top-up each month. It is essential that during initial treatment the bleaching potential of the tooth be reached effectively. Once reached, whitening maintenance only needs to be undertaken approximately three years later. When the patient rewhitens their teeth, they would whiten for a shorter period from three to seven days.

Whitening for life It is expected that patients will whiten their teeth periodically to maintain a white smile. In a 25-year timespan, a patient may whiten four to five times. Maintenance is essential and involves regular professional oral prophylaxis treatment, the use of whitening toothpaste and sometimes a reduction in food and drink that cause staining.

The rise of bleachorexia Over the last 25 years it has been possible to whiten the teeth beyond the original Vita classic shade guides. New shade guides have been developed to match the new shades of white, and porcelain and composite shades have been introduced onto the market to be able to restore these teeth to the new whiter shade. Some patients have developed a syndrome where they continually seek whiter and whiter teeth. This is also associated with body dysmorphic disorder and low selfesteem. The term has been described as bleachorexia (Kelleher, 2014), with patients referred to as being a bleachoholic. It is essential that dentists know how to recognise the syndromes and not be seduced into undertaking unnecessary whitening treatment. These patients can usually be detected early, as their teeth are whiter than their sclera of their eyes, which is often used as a measurement of the whiteness that can be achieved.

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It is essential that when whitening treatment is completed the patient is told that no further whitening is necessary at that point. Each whitening cycle will require the dentist to reassess the patient to assess whether further whitening is necessary.

Conclusion The explosion in tooth whitening techniques research over the last 25 years has demonstrated that the whitening products are safe, effective, predictable to use and have many benefits for patients. Side effects such as sensitivity can be managed well as the newer generations of whitening products now contain extra soothers such as potassium nitrate, fluoride and amorphous calcium phosphate. Patients have benefitted from their new shade of white teeth and these treatments have improved smiles in a natural and noninvasive way. Further clarification in the whitening legislation for under 18s (Kelleher, 2014) is being investigated by the CED in Europe, and these treatments may be able to be used for under 18s, provided they are being used for the treatment of disease, which they are. It is expected that the amount of professional tooth whitening materials available will increase for patients to use under the direction of dentists. What’s more, there are many new innovative whitening products that are being brought onto the market for patients to continue to enjoy a whiter, brighter smile.

References Cvek M, Lindwall A M (1985) External root resorption following bleaching of pulpless teeth with oxygen peroxide. Endod Dent Traumatol 1: 56-60 Greenwall LH (2001) Bleaching techniques in Restorative Dentistry. First edition. Martin Dunitz, aka Taylor and Francis, London Greenwall LH (2009) Treatment considerations for bleaching and bonding white lesions in the anterior dentition. Alpha Omegan 102(4): 121-7

Haywood VB (1991a) Overview and status of mouthguard bleaching. J Esthet Dent 3(5): 157-61 Haywood VB (1991b) Nightguard Vital Bleaching, a history and products update: Part 1. Esthet Dent Update 2(4): 63-6 Haywood VB (1991c) Nightguard Vital Bleaching, a history and products update: Part 2. Esthet Dent Update 2(5): 82-5 Haywood VB, DiAngelis AJ (2010) Bleaching the Single Dark Tooth. Changing the color of just one anterior tooth presents unique challenges. Inside Dentistry 42-52 Haywood VB (2010) Orthodontic caries control and bleaching. Inside Dentistry 6(4): 36-50 Heithersay GS (1999) Invasive cervical resorption: an analysis of potential predisposing factors. Quintessence Int 30: 83-95 Kelleher M (2014) The law is an ass: ethical and legal issues surrounding the bleaching of young patients’ discoloured teeth. Faculty Dental Journal 5(2): 56-67 Kelleher M, Djemal S, Ahmed S, Al-Khayatt, Ray-Chauduri AJ, Briggs P, Porter RW (2011) Bleaching and Bonding for the older patient. Dental Update 38: 294-303 Kelleher MGD, Roe F (1999) The safety-in- use of 10% carbamide peroxide (Opalescence) for bleaching teeth under the supervision of a dentist. Br Dent J 187: 190-194 Li Y, Greenwall L (2013) Safety issues of tooth whitening using peroxide-based materials. Br Dent J 215(1): 29-34 Liebenberg WH (1997) Intracoronal lightening of discoloured pulpless teeth: a modified walking bleach technique. Quintessence Int 28: 771-777 Nutting E B, Poe G S (1967) Chemical bleaching of discoloured endodontically treated teeth. Dent Clin North Am 11: 655-622 Zimmerli B, Jeger F, Lussi A (2010) Bleaching of nonvital teeth. A clinically relevant literature review. Schweiz Monatsschr Zahnmed 120(4): 306-20 Reprinted with permission by Aesthetic Dentistry Today February 2016

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CLINICAL

Adhesive dentistry and the worn dentition Deepa Shah1

Adhesive techniques and materials are increasingly being adopted in the management of tooth wear cases. Modern day composite resins exhibit excellent mechanical and aesthetic properties, are cost effective and provide a relative degree of repairability. This lends them to be an attractive choice of restorative material for generalised tooth wear cases. This article describes the clinical techniques used in the restoration of the worn dentition with composite resin, as illustrated via a clinical case.

Clinical case The patient, a 35-year-old male, presented with generalised tooth wear, consistent with erosive and attrition aetiologies. The dentition was restored with a combination of direct and indirect composite resins, at an increased occlusal vertical dimension (OVD) (Figures 1-3). Following a comprehensive case assessment, a full mouth diagnostic wax-up and intraoral mock-up were carried out. This allowed both myself and the patient to assess the final form and function of the proposed aesthetic and occlusal rehabilitation. The restorations placed were all based on the verified diagnostic wax-up.

Dr Deepa Shah BDS(Hons) MFDS RCS MSc is a member of the Faculty of Dental Surgery of the Royal College of Surgeons of England. She has successfully completed a full-time Masters programme in conservative dentistry at the UCL Eastman Dental Institute. She is based in a private prosthodontic practice in the West End of London, and is a senior clinical teaching fellow at the UCL Eastman Dental Institute.

Figures 1-3: Preoperative occlusal and anterior retracted views.

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CLINICAL

Restoration of the anterior teeth The maxillary and mandibular anterior teeth were built-up using indirect and direct composite resin, respectively. The mandibular anterior teeth were built-up first, to set the occlusal plane and facilitate later fabrication of the palato-incisal maxillary composite restorations. A silicone putty matrix was fabricated from the diagnostic wax-up. The teeth were built-up using a composite layering technique with a microhybrid restorative composite (Gradia Direct, GC) (Figures 4a-4c). The maxillary anterior teeth were then prepared by smoothing over any sharp line angles and flattening of the incisal edges. Any exposed dentine was sealed using the immediate dentine sealing protocol described by Magne (2005). A full arch impression was made in addition cure silicone. Retraction cord was used on the palatal aspect to allow exposure of the ring of enamel present. A jaw registration record in centric relation (CR) at the desired OVD and a facebow recording were made. The casts were then mounted onto a semi-adjustable articulator for fabrication of the maxillary palato-incisal composite restorations (Figures 5 and 6). These restorations were cemented under rubber dam. The fit surface of the composite restorations were prepared by sandblasting with 50μm aluminium oxide particles, cleaning with alcohol and wetting with a composite primer (GC). The tooth surface was prepared by sandblasting with 50μm aluminium oxide particles, etching for 30 seconds with 30% phosphoric acid and wetting with adhesive resin (Optibond FL, Kerr). The restorations were cemented using warm microhybrid restorative composite material matched to the shade of the underlying tooth. The direct composite additions to the maxillary posterior teeth were also carried out at this stage (Figures 7-9). Prior to the restoration of the mandibular posterior teeth, the space between the posterior teeth was maintained with the use of pillars of composite restorative material spot-etched and bonded to the mandibular posterior teeth. An alternative approach would be to fabricate provisional acrylic onlays based on the posterior diagnostic wax-up, which can be shrink fitted and locked into place with acrylic resin.

4b 4c

Figures 4a-4c: Direct composite build-up of mandibular anterior teeth.

Restoration of the mandibular posterior teeth The mandibular posterior teeth were prepared for indirect composite onlay restorations. Silicone reduction guides were used from the diagnostic wax-up to judge if any occlusal reduction was required, allowing for 2mm of occlusal composite. Definitive and smooth chamfer margins of about 1mm were prepared on the buccal and lingual axial walls to

Figures 5-6: Maxillary palato-incisal composite restorations.

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Figures 7-9: Cementation of the maxillary palato-incisal restorations.

Figures 10-11: Preparation of mandibular posterior teeth for indirect composite onlay restorations.

augment the preparations with some resistance form, and to facilitate location of the onlays at cementation. The ideal interproximal preparation for occlusal onlays requires the preparation to be carried below the contact point, to facilitate access to the margin. However, as alluded to by Mizrahi (2008), in worn posterior teeth, a wide and broad contact area is often seen extending close to the

gingiva. Preparing through this contact area would result in excessive destruction of sound tooth tissue and, more importantly, a high risk that the base of the restoration in the interproximal region will finish onto dentine, giving an increased risk of microleakage (Tjan, Dunn, Sanderson, 1989). Therefore, in this case, the interproximal contacts were not cleared (Figures 10 and 11).

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12a

12b

Figures 12a-12b: Mandibular composite onlay restorations.

13a

13b

13c

13d

Figures 13a-13d: Cementation of mandibular posterior indirect composite onlay restorations (note: substantial occlusal enamel remaining for bonding to).

The posterior restorations were cemented under rubber dam, again using a warmed restorative microhybrid composite

material matched to the shade of the underlying tooth, and using the protocol described above (Figures 12 and 13).

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Discussion

16 Figures 14-16: Postoperative occlusal and anterior retracted views.

The patient was provided with a fully restored dentition, with a mutually protected occlusion and improved aesthetics (Figures 14-16).

Maintenance and future treatment The decision was made at the start of treatment that a postoperative Michigan splint would be made. This will serve to maintain the occlusal stability and protect the restorations. The patient was made aware that the restorations would be likely to require minor repairs in the future (Hemmings, Darbar, Vaughan, 2000; Gulamali et al, 2011) and he was happy to accept this. Future planned treatment may include the placement of labial porcelain veneers on the maxillary anterior teeth. This might be necessary not only to improve the aesthetics of the maxillary anterior teeth, but also to strengthen and stiffen the teeth following biomimetic principles, especially if frequent cracks or breakages occur affecting the restorations on the anterior teeth. At the two-year follow-up appointment, aesthetic and occlusal stability was evident, and no repairs have been required.

The advent of adhesive dentistry has revolutionised modern day dental practice. Its application in cases with tooth wear is most attractive, allowing conservation of already depleted tooth structure. Composite resin has been shown to be a suitable restorative material for restoration of localised and generalised tooth wear, giving functional and aesthetic results. However, the forgiving and resilient nature of composite resin restorative materials should not be taken for granted. For the most part, patients with generalised and excessively worn dentitions will be treated within a practice environment and will incur great costs to time and money, as well as personal stresses with lengthy and intrusive treatment. It has already been noted that failures can, and will, occur with the use of composite resins to restore worn dentitions, and maintenance is required (Gulamali et al, 2011). Therefore, the occlusal management and planning of these cases to control the stresses placed on the restorations and minimise later intervention is essential. This goes hand-in-hand with meticulous bonding protocols using adequate isolation measures (ideally rubber dam). It is important not to be complacent in the use of these materials. Plan and handle each restoration as if it is a brittle feldspathic ceramic and this will lead to precision and predictability in each case.

Further information The author would like to thank dental technician Mr JacquesAntoine Tribault for his skill and expertise in the production of all of the laboratory work shown.

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References Bartlett DW, Evans DF, Anggiansah A, Smith BG (1996) A study of the association between gastro-oesophageal reflux and palatal dental erosion. Br Dent J 181(4): 125-131 Bartlett D, Ganss C, Lussi A (2008) Basic Erosive Wear Examination (BEWE): a new scoring system for scientific and clinical needs. Clin Oral Investig 12 (Suppl 1): s65-68 Berry DC, Poole FG (1976) Attrition: possible mechanisms of compensation. J Oral Rehab 3: 201-206 Cochrane NJ, Cai F, Huq NL, Burrow MF, Reynolds EC (2010) New approaches to enhanced remineralisation of tooth enamel. J Dent Res 89(11): 1187-1197 Dahl BL, Krogstad O, Karlsen K (1975) An alternative treatment in cases with advanced localised attrition. J Oral Rehab 2: 209-214 Dahl BL, Krogstad O (1982) The effect of a partial bite raising splint on the occlusal face height. An x-ray cephalometric study in human adults. Acta Odontol Scand 40: 17-24 Darbar UR (1994) The treatment of palatal erosive wear by using oxidised gold veneer: a case report. Quintessence Int 25(3): 195-197 Dietschi D and Argente A (2011) A Comprehensive and conservative approach for the restoration of abrasion and erosion. Part 1: concepts and clinical rationale for early intervention using adhesive techniques. Eur J Esthet Dent 6: 20-33 Edelhoff D, Sorensen JA (2002) Tooth structure removal associated with various preparation designs for anterior teeth. J Prosthet Dent 87: 503-509 Edelhoff D, Sorensen JA (2002) Tooth structure removal associated with various preparation designs for posterior teeth. Int J Periodontics Restorative Dent 22: 241-249 Fradeani M, Barducci G, Bacherini L, Brennan M (2012) Esthetic rehabilitation of a severely worn dentition with minimally invasive prosthetic procedures (MIPP). Int J Periodontics Restorative Dent 32: 135-147 Gough MB, Setchell DJ (1999) A retrospective study of 50 treatments using an appliance to produce localised occlusal space by relative axial tooth movement. Br Dent J 187: 134-139 Gow AM, Hemmings KW (2002) The treatment of localised anterior tooth wear with indirect Artglass. Results after two years. Eur J Prosthodont Restor Dent 10: 101-105 Gulamali AB, Hemmings KW, Tredwin CJ, Petrie A (2011) Survival analysis of composite Dahl restorations provided to manage localised anterior tooth wear (10 year follow-up). Br Dent J 211(4): E9 Hemmings KW, Darbar UR, Vaughan S (2000) Tooth

wear treated with direct composite restorations at an increased vertical dimension: Results at 30 months. J Prosthet Dent 83: 287-293 Hussey DL, Irwin CR, Kime DL (1994) Treatment of anterior tooth wear with gold palatal veneers. Br Dent J 176(11): 422-425 Kelleher M, Bishop K (1999) Tooth surface loss: an overview. Br Dent J 186(2): 61-66 Klasser GD, Greene CS, Lavigne GJ (2010) Oral appliances and the management of sleep bruxism in adults: a century of clinical applications and search for mechanisms. Int J Prosthodont 23: 453-462 Litonjua LA, Andreana S, Bush PJ, Cohen RE (2003) Tooth wear: Attrition, erosion and abrasion. Quintessence Int 34: 435-446 Magne P (2005) Immediate Dentin Sealing: A fundamental procedure for indirect bonded restorations. J Esthet Restor Dent 17: 144-155 Magne P, Stanley K, Schlichting LH (2012) Modeling of ultrathin occlusal veneers. Dent Mater 28: 777-782 Milosevic A (1999) Eating disorders and the dentist. Br Dent J 186(3): 109-113 Mizrahi B (2008) Combining traditional and adhesive dentistry to reconstruct the excessively worn dentition. Eur J Esthet Dent 3: 270-289 Nohl FS, King PA, Harley KE, Ibbetson RJ (1997) Retrospective survey of resin-retained cast-metal palatal veneers for the treatment of anterior palatal tooth wear. Quintessence Int 28(1): 7-14 Poyser NJ, Porter RW, Briggs PF, Chana HS, Kelleher MG, Patel MM (2007) The evaluation of direct composite restorations for the worn mandibular anterior dentition â&#x20AC;&#x201C; clinical performance and patient satisfaction. J Oral Rehab 34: 361-376 Redman CDJ, Hemmings KW, Good JA (2003) The survival and clinical performance of resin based composite restorations used to treat localised anterior tooth wear. Br Dent J 194: 566-572 Reynolds EC (1997) Remineralisation of enamel subsurface lesions by casein phosphopeptide-stabilised calcium phosphate solutions. J Dent Res 76(9): 1587-1595 Schlichting LH, Maia HP, Baratieri LN, Magne P (2011) Novel-design ultra-thin CAD/CAM composite resin and ceramic occlusal veneers for the treatment of severe dental erosion. J Prosthet Dent 105: 217-226 Smith BG, Knight JK (1984) An index for measuring the wear of teeth. Br Dent J 156(12): 435-438 Spijker AV, Rodriguez JM, Kreulen CM, Bronkhorst EM,

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Bartlett DW, Creugers NHJ (2009) Prevalence of tooth wear in adults. Int J Prosthodont 22: 35-42 The Health and Social Care Information Centre (2011) Disease and related disorders â&#x20AC;&#x201C; a report from the Adult Dental Health Survey 2009. The Health and Social Care Information Centre Tjan AHL, Dunn JR, Sanderson IR (1989) Microleakage patterns of porcelain and castable ceramic laminate veneers. J Prosthet Dent 61: 276-282 Vailati F, Belser UC (2008) Full-mouth adhesive rehabilitation of a severely eroded dentition: The three-step technique. Part 1. Eur J Esthet Dent 3: 30-44 Vailati F, Belser UC (2008) Full-mouth adhesive rehabilitation of a severely eroded dentition: The three-step technique. Part 2. Eur J Esthet Dent 3: 128-146

Vailati F, Belser UC (2008) Full-mouth adhesive rehabilitation of a severely eroded dentition: The three-step technique. Part 3. Eur J Esthet Dent 3: 236-257 Vailati F, Belser UC (2010) Classification and treatment of the anterior maxillary dentition affected by dental erosion: the ACE classification. Int J Periodontics Restorative Dent 30(6): 559-571 Van Meerbeek B, Van Landuyt K, De Munck J et al (2006) Bonding to enamel and dentin. In: Fundamentals of Operative Dentistry (A contemporary approach). Summitt JB, Robbins JW, Hilton TJ, Schwartz RS, eds. Quintessence. pp183-260 Reprinted with permission by Aesthetic Dentistry Today February 2016

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PRODUCTS

MIELE

VOCO

DISINFECTOR

IONOLUX®

The new generation disinfector features a fresh modern design, with versions available in white and stainless steel, depending on the model (PG8591 comes only in Stainless Steel). The new control panel consists of a single, flush sheet of stainless steel without protruding controls and features ‘touch-on-steel’ controls. This control panel is a Miele unique feature and makes for simple and fast surface cleaning. The display provides information on the selected programme and the programme status. Frequently used programmes can be assigned to three direct-access buttons. This means favourite programmes can be launched at the touch of a single button!

Ionolux is a light-curing glass ionomer restorative material in VITA© shades A1, A2, A3, A3.5 and B1, which combines the advantages of glass ionomer materials which those of composites. Application of Ionolux is quick, and the material can be modelled with ease without sticking to the instrument. Ionolux not only makes conditioning of the dental hard tissue unnecessary, there is also no need to apply a final coat of varnish. Polymerisation times are short and practice-oriented, at 20 seconds per 2-mm layer. Ionolux is easy to polish, it is biocompatible and releases fluorides.

KAVO

ESSENTIA

ESTETICA E50 LIFE

A universal light-cured composite system which brings high level aesthetics back to the essentials of basic dentine and enamel layering in a simplified system with just 7 shades. GC’s advanced filler technologies forged the development of dentine and enamel shades that are structurally different so they can move light and mimic the natural differences in dentine and enamel. Then, by intuitively matching the natural aging of teeth, a simplified but highly aesthetic system is created which allows all your restoration needs to be fulfilled with just 7 shades! Using a simple 2-layer system that mimics dentine & enamel and the aging of natural teeth all your aesthetic restorations can be created with just 7 shades.

Our proven Ionolux is now available in the new and particularly practical application capsule, distinguished by the fact that an activator is no longer required. The combined advantages of glass ionomer materials and composites, easy to use with Ionolux: place the filling, polymerise, finish, ready!

The KaVo ESTETICA E50 LIFE is simple to use, expand, and is most of all reliable. The E50 LIFE features a new patient chair, camera, and software communication system. Direct keys without double allocation guide you intuitively to your goal with no time-consuming familiarisation or tiresome searching for functions during treatment. In conjunction with the clearly designed screen and the tried and tested KaVo colour scheme, you will quickly find your way. This will guarantee a smooth workflow and will allow you to have more effective treatment time. •Higher maximum patient weight - up to 185kg •Extended highest and lowest positions •Integrated Trendelenburg movement for patient comfort •Optimised soft upholstery form

QUINTESSENCE

MEDICAL MICROBIOLOGY AND IMMUNOLOGY FOR DENTISTRY Nejat Duzgunes This clinically oriented textbook explores medical microbiology and immunology as they relate to the practice of dentistry, including sections on the microbiologic basis of caries, periodontal disease, and endodontic infection. The book begins with a thorough discussion of immunology and then systematically covers the bacteria, fungi, viruses, and parasites that affect the human body as well as their oral manifestations. Extremely detailed illustrations throughout aid the reader in comprehending the

complex interactions involved in processes such as cellular immunity, bacterial and fungal infiltration, biofilm and plaque formation, and virus entry and replication. Sections on recombinant DNA technology, molecular diagnostics and genomics familiarize the reader with new technologies and emerging fields that will impact future practice. Notable discoveries in molecular biology are highlighted throughout, and research questions are featured as well to engage understanding and critical thinking. Finally, an appendix of cases in medical microbiology challenges the reader to pose diagnoses based on clinical symptoms. This book will no doubt become the definitive textbook on microbiology for dental students and dentists. Q-5120803 | 306 pp; 272 illus

All products available from: HENRY SCHEIN HALAS • Tel: 1300 65 88 22 • www.henryschein.com.au 62 INTERNATIONAL DENTISTRY – AUSTRALASIAN EDITION VOL. 11, NO. 2

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PRODUCTS

SHERMAN

MOCOM

NEW SWEET TOOTH PUFFY STICKERS

DISINFECTOR H10 TETHYS Renowned Italian autoclave manufacturer, Mocom, has launched a new generation of washer disinfector units. The Mocom Tethys H10 Hybrid Disinfection Device expands the traditional role of the thermal washer disinfector by adding ultrasonic cleaning as an initial step and delivering instruments dry and ready for packaging and sterilisation at the end of a 35-minute cycle. • Easy installation on normal bench

Comes in 6 assorted designs. Create Fun in your surgery! Dental Hygiene is Cool! Stickers are a great motivator to Brush, Floss and Rinse every day. Stickers encourage everyone to smile and brighten everyone's day. Nothing brightens a day as much as a smile. Give the sticker to your little patients or use the sticker to seal your envelopes and see how many smiles you get.

• Touch-screen control panel • Compact dimensions • Washing with ultrasounds • Thermal disinfection at 90°C • Effective drying • Short cycle time • Full compliance with standard EN 15883-1/2

KAVO

VOCO

PRIMUS 1058 LIFE

IONOSELECT®

The Primus 1058 Classic was the top-selling treatment centre from KaVo. In the development of the follow-up model Primus 1058 Life, KaVo have maintained and further optimised its values. The 1058 Life has been designed to accommodate maximum loads, tested with quadruple strain and the benefits of every new function have been examined to ensure all newly developed functions offer real value. All newly developed functions offer real added value. This applies to the considerably quieter motor, the ergonomic optimisation of the patient chair and the well thought out, simplified new dentist element. •Higher maximum patient weight - up to 185kg •Extended highest and lowest positions •New dentist element with intuitive design •Improved operating concept with direct selection buttons

IonoSelect is a universal glass ionomer material, the world’s first product suitable for use in the four main GIC indications: luting, restorations, core build-up, cavity lining. IonoSelect for restorations features excellent physical properties, such as high compressive strength, good adhesion to enamel and dentine, as well as high levels of biocompatibility and fluoride release. It is suitable for restorations of non-occlusionbearing class I cavities, semi-permanent restorations of class I and II cavities, restorations of class III and V cavities, treatment of cervical lesions and root caries, temporary restorations, cavity lining, restoration of deciduous teeth and extended fissure sealing. Application of IonoSelect is equally simply for all indications. The material is ready to use immediately after mixing and can be applied using an applicator. Iono Select in the new VOCO application capsules is compatible with all standard applicators.

QUINTESSENCE

MEDICAL EMERGENCIES IN DENTAL PRACTICE Orrett E Ogle, Harry Dym, Robert Weinstock The active use of preventive measures is invaluable in clinical practice, but the best way to ensure effective management of a medical emergency is to be prepared in advance. Practitioners and their entire dental staff

must be ready to confront medical emergencies that may arise during treatment with sufficient medical knowledge to initiate appropriate primary treatment. This accessible manual addresses the most common medical emergencies encountered during dental treatment. Step-by step treatment guidelines and decision-making algorithms outline the steps for immediate treatment and make this practical book an essential office manual. Q-5120804 | 200 pp; 156 illus

All products available from: HENRY SCHEIN HALAS • Tel: 1300 65 88 22 • www.henryschein.com.au 64 INTERNATIONAL DENTISTRY – AUSTRALASIAN EDITION VOL. 11, NO. 2

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