INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
Contents
Adhesive science
Structure of enamel
Adv/disadv of banding & bonding
Direct bonding www.indiandentalacademy.com
Broad Rationale of Adhesive Science ď Ź
Charect. Req.& prop. Of orthod. material
molecular
structural
Why do materials cohere at all? www.indiandentalacademy.com
Broad Rationale of Adhesive Science
Range of attractive forces that may operate in & b/w molecules Covalent bonds Hydrogen bonds Weak intermolecular forces Self coherent solids Gold & waxes Welding & brazing www.indiandentalacademy.com
Broad Rationale of Adhesive Science
Most other solids (tooth & ortho brackets) Surface forces operate very short dist & ↓ rapidly with inverse 6th – 7th power of separation Solids- micro. rough
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Broad Rationale of Adhesive Science FLUID AGENT Contact angle
Smaller contact angle
Viscosity
Larger contact angle
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Broad Rationale of Adhesive Science
PHASE CHANGE Physical means Chemical setting mechanism Dimensionally stable Volumetric expansion/shrinkage
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Broad Rationale of Adhesive Science
Adhesion :-- Attraction b/w unlike molecules
Cohesion :-- Attraction b/w like molecules
Mechanical bonding:-- Strong attachment of 2 substances accomplished mechanically rather than by molecular attraction. penetration of adhesive into micro & submicro irregularities www.indiandentalacademy.com
BONDING= ADHESION+ATTACHMENT
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Enamel
Highly mineralized tissue
Hardest tissue in human body
Clinically visible
No regenerative capacity
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Morphology of Enamel
Enamel prisms (rods) – 5-12 million Extend from DEJ to outer surface Prismless enamel
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Morphology of Enamel
Longitudinal section under microscope
Wider – Prisms
Narrower – Prism tail
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Morphology of Enamel ď Ź
Cross section under electron microscope
- Keyhole pattern or fishlike apperance.
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Morphology of Enamel
Keyhole pattern
Head – incisal region
Tail – cervical region
Prisms contain hydroxyapatite crystals www.indiandentalacademy.com
Morphology of Enamel ď Ź
Hydroxyapatite crystals
- Run parallel to long axis of prism and become perpendicular as they approach tail.
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Acquired pellicle
Precipitation of salivary glycoproteins
Removed by pumicing
Reform almost immediately
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Factors affecting enamel solubility
Pre – eruptive factors
Post – eruptive factors
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Factors affecting enamel solubility
Pre – eruptive factors
Affect chemical and histological characteristics - Hypoplasia - Hypocalcification - Fluorosis
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Factors affecting enamel solubility ď Ź
Post – eruptive factors
- Topically applied fluorides - Organic pellicle - Plaque www.indiandentalacademy.com
Factors affecting bonding to ideally etched surface
ď Ź
Patient
Operator
- salivary contamination - contact with lips and tongue - exhalation vapor
- oil / water via spray - rubbing /touching etched surface
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Direct Bonding: Past and present BANDING
- W.E. Magill – 1871
Negative factors – - Time and skill - Impacted / partially erupted teeth - Decalcification / discoloration - Gingival irritation - Closure of band spaces - Unaesthetic - Placement of separators is painful www.indiandentalacademy.com
The goal was to have brackets, tubes and other attachments directly cemented on the tooth surface to eliminate problems encountered with metal bands.
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Banding preferred to bonding
Teeth that receive heavy intermittent forces eg. Upper 1st molar
Teeth that need both labial and lingual attachments
Teeth with short clinical crowns
Teeth surfaces difficult to bond eg. Amalgam rest., Porcelain rest., Fluorosed teeth. www.indiandentalacademy.com
Advantages of bonding
Esthetics Faster and simpler Less patient discomfort Arch length not increased No band space closure Partially erupted or fractured teeth can be controlled Lingual orthodontics www.indiandentalacademy.com
Advantages of bonding
Interproximal enamel reduction and composite build up possible
Bond artificial tooth surface
Caries risk eliminated
Bracket may be recycled
More hygienic
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Disadvantages of bonding
Weaker than bands
Better access for cleaning does not guarantee better
No protection against interproximal caries
Rebonding > recementing Debonding > debanding www.indiandentalacademy.com
Bonding Procedure
Cleaning Enamel conditioning
moisture control
enamel pretreatment
Sealing Bonding
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Cleaning ď Ź
Remove organic pellicle and plaque.
ď Ź
Pumicing using rubber cup / polishing brush
REISNER et al Buccal surfaces lightly abraded with TC bur at slow speed (25000rpm) > Pumicing for 10 sec.
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Enamel conditioning 1. Moisture control Lip expanders Cheek retractor Saliva ejectors Tongue guards Salivary duct obstructors(dri-angles) Cotton or gauze rolls Antisialagogues www.indiandentalacademy.com
Antisialogogues
Both tab. & injectable solns : Banthine pro- Banthine Atropine sulfate Excellent & rapid saliva flow restriction proBanthine---- no longer advised Banthine tab. – 50mg/45kg(100lb) body wt. in a sugar free drink,15 min before bonding www.indiandentalacademy.com
Enamel conditioning 2.Enamel pretreatment ď Ź
Acid etching
ď Ź
Other alternatives to acid etching 1. Crystal growth 2. Sand blasting / Air abrasion 3. Laser etching
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Acid Etching
1955 Buonocore - 85% phosphoric acid for 30 sec. 37% phosphoric acid – 15 - 60 sec Nordenvall et al - 15 sec for deciduous & young permanent teeth 30 – 60 sec for adult teeth Longer periods – less bond strength due to loss of enamel structure
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Acid Etching Procedure Isolation Gentle application of etchant – should not be rubbed Rinsed with water spray Dry with moisture and oil free source ( pref with chip blower) Avoid salivary contamination– if it occurs, re etch the tooth. www.indiandentalacademy.com
Acid Etching ď Ź
Dull frosty white appearance
ď Ź
Teeth that do not appear dull and frosty white should be re - etched www.indiandentalacademy.com
Acid Etching ď Ź
Alternative acids for etching - 10% Phosphoric acid - 10% Maleic acid - 2.5% Nitric acid - Polyacrylic acid
Most widely used is 30 – 50% ( 37%) phosphoric acid www.indiandentalacademy.com
Rationale of etching
Gwinnet, Matsui and Buonocore & others Primary attachment mechanism of resin is “resin tags”. Micromechanical bond
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Rationale of etching
Removes about 3-10 microns of enamel surface Etching also increases the wetability and surface area of the enamel substrate. Resin tag penetrate upto the depth of 80 um or more
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Conc. Of etchant Most widely used concns. of phosphoric acid from 30% - 50% with an application of 30 -60 seconds. 20 – 50% / 60 sec. Most retentive surface ( Silverstone ) > 50% phosphoric acid – Monocalcium phosphate monohydrate < 27% phosphoric acid Dicalcium phosphate dihydrate
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Acid for etching Maleic 10% similar
Phosphoric 37% similar
Bond st
Morphological pattern similar
‘’
Depth of etched surface less www.indiandentalacademy.com
Nitric acid 2.5% less effective
Patterns of etching According to Retief ď Ź Type 1 - Selective removal of enamel prism cores - Peripheries intact (honey comb app.)
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Patterns of etching ď Ź
Type 2 - Reverse process - Peripheries removed - Cores intact (cobble stone app.)
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Patterns of etching ď Ź
Type 3 - surface loss w/o exposing underlying prisms
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Effects of enamel etching time on morphology Barkmeier,Gwinnett & Shaffer JCO January 1985 ď Ź
The morphology of enamel following etching for 15 or 60 secs. differed only in the amount of gross enamel loss with 50% phosphoric acid
ď Ź
No morphological differences in the pattern or character of the etched enamel rods. www.indiandentalacademy.com
Bond strength with various etching times Wang et al AJO-DO July 1991
Compared the tensile bond strength at various etching times 15, 30, 60, 90, 120 secs 37% Phosphoric acid TBS was not statistically different for 15, 30, 60, 90 secs TBS decreased – 120 secs Amount of enamel fragments increased in proportion to the length of the etching times Optimal etching time should be 15sec www.indiandentalacademy.com
SEM Study & SBS measurement with 5% & 37% phosphoric acid AJO-DO oct,1995 Wasundhara A. Bhad, Pushpa V. Hazarey, G.D.C.Nagpur ď Ź
PURPOSE: To use an acid concn. Of H3PO4 that yielded max. bond strength with minimal enamel loss & to measure & compare the SBS b/w 5% & 37% H3PO4 with 60 sec acid etching time. www.indiandentalacademy.com
SAMPLE: 60 Premolars 1st grp 10 teeth, used to study etching pattern with 5% & 37% H3PO4
2nd grp 50 teeth, used to study & compare SBS after etching with 5% & 37% H3PO4
CONCLUSION :
5%H3PO4 can be used for etching tooth surface before bonding instead of 37% H3PO4 concn; as with 5%H3PO4, there is minimal enamel loss & bond strength is not affected www.indiandentalacademy.com
Variations in acid-etch patterns with different acids and etch times Alastair Gardner, Ross Hobson, AJO 2001 ď Ź
ď Ź
Compared the enamel etch patterns produced by 37% phosphoric acid and 2.5% Nitric acid for 15, 30 & 60 secs Concluded - 37% phosphoric acid > 2.5% nitric acid for all three applications -optimum time for applying 37% phosphoric acid is 30 sec www.indiandentalacademy.com
Acid etching in pri. teeth
Outer 30um of pri. Enamel is prism less no uniform etch
Higher organic content
Prism rods approach the surface at greater angle www.indiandentalacademy.com
Acid etching in pri. teeth
STUDIES: SILVERSTONE:- 120 sec etch necessary to establish proper enamel porosity MUELLER(1977):- By increasing the etch time an increase in tag formation was seen NORDENVELL et al :- Compared pri. Young & mature perm. Teeth using var. etch times b/w 15-60 sec. found that 15 sec gave greatest surface irreg. in pri. teeth. REDFORD:- etch time of 15 sec with 38% phos acid was adeq for pri. teeth. www.indiandentalacademy.com
Commonly asked questions
Should the etch cover the entire facial enamel or only a small portion outside the bracket pad?
Are gels preferable to solutions?
What is the optimal etching time? Is it different for young and old teeth?
Is sandblasting as effective as acid etching? www.indiandentalacademy.com
What is the preferred procedure for deciduous teeth?
Is prolonged etching necessary when teeth are pretreated with fluoride?
Will incorporation of fluorides in the etching soln increase the resistance of enamel to caries attack?
Is etching permissible on teeth with internal white spots? www.indiandentalacademy.com
ď Ź
How much enamel is removed by etching and how deep are the histologic alterations? Are they reversible? Is etching harmful?
ď Ź
Should other means than acid etching( e.g. crystal growth ) be preferred?
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Alternatives to acid etching
Crystal growth
Sand blasting / Air abrasion
Laser etching
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Iatrogenic factors Maijer & Smith 1986 AJO-DO 1.Loss of enamel caused by etching 10-20 um lost - acid etch 6-50 um lost - after debonding 2.Retention of resin tags – discoloration of enamel Resin tags – 80um or more U/V cured resin – didn’t contain u/v absorber
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Iatrogenic factors Maijer & Smith 1986 AJO-DO 3.Leakage at the bracket interface Bracket corrosion and staining Small pores – pathway for bact., stains etc. Ceen & gwinnett and maijer & smith – stain due to biodgradation of the metals
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Iatrogenic factors Maijer & Smith 1986 AJO-DO 4.Enamel loss fracturing of enamel at time of debonding. Reported by Reteif(1974) and Reteif & Denys(1979) 5.A rougher surface with enamel cracks 2 step procedure should be used 1st step – debonding pliers,hand instru,u/s scalers 2nd step – abrasive cups/discs with polishing medium www.indiandentalacademy.com
Iatrogenic factors Maijer & Smith 1986 AJO-DO 6.A softer enamel surface with lower fluoride content, more predisposed to decalcification ď Ź Acquired fluoride â&#x20AC;&#x201C; 10um
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Crystal growth
1st demonstrated by Smith & Cartz Maijer & Smith 1979 did lot of work Polyacrylic acid + sulfate ion long needle shaped crystaline deposit CALCIUM SULPHATE DIHYDRATE (Spherulitic habit)
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Crystal growth
Crystalline interface produced tensile bond strength equivalent to conventional acid etched surface. Debonding – fracture at crystal resin interface Other soln – Sulphuric acid anion ( more reliable and uniform growth )
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Crystal growth
MECHANISM OF RETENTION Calcium sulphate crystals must enucleate from bound calcium
To achieve this some etching is required
Enamel solubility ~ crystal enucleation
Mechanical attachment is created around the crystalline interface and superficially etched enamel.
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Crystal growth
Artun and Bergland 1984 Sulphuric acid – crystals not as long and needle like as with polyacrylic acid but were rounder and flatter. Hence debonding was easier.
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Advantages of Crystal growth
Debonding quicker and easier
No damage to enamel
Minimal effect on outer fluoride containing enamel
No resin tags left behind
Possibility of incorporating fluoride in crystal interface – anticariogenic action. www.indiandentalacademy.com
Crystal growth – Procedure
One drop of viscous liquid placed on tooth surface Left undisturbed for 30 sec No mechanical agitation Rinsed for 20 sec Forceful water spray to be avoided as it will break crystals Dull whitish deposit Bracket bonded in usual way.
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Alternatives to acid etching
Crystal growth
Sand blasting / Air abrasion
Laser etching
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Sand blasting / Air abrasion
Makes use of high speed stream of aluminium oxide particles ( 50-90 um) propelled by air pressure Produces rough surface
Used for cavity preparation
Remove old composite resin
Improve the retentive surface of loose bracket www.indiandentalacademy.com
Sand blasting / Air abrasion
Could contribute to better bond strength with less enamel loss Factors affecting bond strength Particle size Air pressure Exposure time Microstructure of enamel surface www.indiandentalacademy.com
Sand blasting Albert Feilzer,AJO Jan 2000 Compared bond strength and enamel loss b/w sand blasting and conventional acid etching at varying exposure times and air pressure Enamel loss â&#x20AC;&#x201C; equal or less depend on time of exposure and pressure Bond strength â&#x20AC;&#x201C; Sand blasting < Acid etching www.indiandentalacademy.com
Conclusion Sandblasting ď Ź
Crystal growth
Enamel loss
controlled by operator ď Ź
Acid etching
remineralized
less
Bond strength low than A E
Optimum www.indiandentalacademy.com
low than A E
Alternatives to acid etching
Crystal growth
Sand blasting / Air abrasion
Laser etching
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Laser etching
LASER – Light Amplification by Stimulated Emission of Radiation
Maiman 1960 – developed first laser
Generation of monochromatic, coherent & collimated radiation by a suitable laser medium in a optical resonator www.indiandentalacademy.com
Laser etching
Laser unit – 3 elements
1.Lasing medium - liquid/solid/gas 2.Energy source - xenon flash lamp/electrical discharge 3.Optical resonator- 3prop. coherence collimation monochromacity www.indiandentalacademy.com
Laser etching
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Laser etching USE OF LASER SYSTEM
Soft & hard tissue lesions t/t
Caries prevention
Desensitization of teeth
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Laser etching Classification ď Ź According wavelength 1. UV range ( Krypton fluoride, Argon fluoride) 2. Visible light ( Helium Neon, argon laser ) 3. Infrared range (carbon dioxide , Nd: YAG )
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Laser etching of enamel for direct bonding Von Fraunhofer 1993, No.1 AO
Phosphoric acid – 30 sec. 4 power settings on the laser etching unit were used: 80mJ, 1W, 2W and 3W. Melting and ablation of enamel surface (roughness) Result Acceptable shear bond strength,(0.6kg/mm), could achieved at laser power settings of 1 to 3W but not at the lowest setting (80 mJ). Shear bond strengths lower than acid etching. www.indiandentalacademy.com
Laser etching Dr. Francis 2001
Aim – to compare tensile & shear bond strength obtained by acid etching & krypton flouride excimer laser. KrF(440MJ/cms, 460 and 480) Optimum bond strength achieved with 460 & 480 TBS - highest with 460 then480 & acid etching SBS- highest with 480 both Least with 440 Adhesive more on E with acid etching www.indiandentalacademy.com
Bonding Procedure
Cleaning
Enamel conditioning
- Acid etching - Crystal growth - Sandblasting - Laser etching Sealing Bonding www.indiandentalacademy.com
Sealing Sealer / Primer / Intermediate resin Low viscosity resin which is applied prior to bonding ď Ź
VARIOUS CONCEPTS Necessary to achieve proper bond strength Resist. to microleakage Both reasons Not needed at all www.indiandentalacademy.com
Sealing
Sealants 2 types light cured chemically cured
CEEN & GWINNETT Light cured sealant protect the enamel adjacent to the brackets from dissolution & subsurface lesions Chemically cured polymerize poorly & have low resist. to abrasion www.indiandentalacademy.com
Evaluation of sealant in Orthodontic bonding Wei Nan Wang et al AJO 1991
Evaluated the TBS with & w/o use of sealant
No statistically significant difference in the bond strength of the two evaluated groups
The distributions of debonding interface between groups were similar and also had no statistical difference.
Sealant in the two-paste self polymerize bonding system for enhanced strength is unnecessary. www.indiandentalacademy.com
Sealing
However the use of sealant
May offer extra protection to enamel during debonding
As chances of enamel surface detachment without use of sealant was greater. www.indiandentalacademy.com
Self Etch Primer
Traditional orthodontic bonding systems
Fourth-generation bonding systems such as(AllBond 2)
Fifth-generation bonding (Prime & Bond NT) Etchant & Primer + Adhesive into one step.
Sixth-generation adhesive (Prompt L-Pop, Transbond Plus Self Etching Primer) www.indiandentalacademy.com
Self Etch Primer ď Ź ď Ź
Prompt L Pop Transbond self etch primer
Liquid begins to etch as soon as it is applied Saves time www.indiandentalacademy.com
Self Etch Primer Composition of Prompt L-Pop –
Methacrylate phosphoric acid ester Phosphine oxide Parabenes Stabilizer A fluoride complex Water www.indiandentalacademy.com
Procedure For Self Etch
Teeth are pumiced
Self etch primer gently swirled on to each enamel surface for 2 to 5 secs
As pH rises , etchant is converted to primer
Primer is thinned with burst of air
No rinsing with water
Bracket then bonded in usual way. www.indiandentalacademy.com
Procedure for self etch primer
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Self Etch Primer - studies
Rueggeberg et al (2000) - promt L-Pop w/o acid etch produce = bond strength as conventional bracket placement Hitmi (2000)- no signi. diff b/w promt L-Pop & 37% phosphoric acid Bergeron et al (2000)- resin enamel bond strength of diff self etching primer including promt L-Pop, was similar to or better than multistep www.indiandentalacademy.com
Self Etch Primer - studies ď Ź
Fritz et al(2001)- bonding with 3 self etching primer(Clearfil SE Bond,Clearfil Liner Bond 2V& Novabond)was = phos acid
ď Ź
Bishara et al(2001)- self etching primer prod a signi lower, but clinic acceptable, SBS compared to acid etch when Transbond XT composite used
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Self Etch Primer - studies
SHADOW ET AL (2002 JCO) clinical eval. bond failure rates with a new self ething primer- Transbond Plus Conclusion Traditional AE 15 sec = etch & 15-20 sec = rinsing.10 sec= primer + curing Transbond Plus =3 sec Bracket retention > traditional www.indiandentalacademy.com
Hydrophilic Primer ( MIP )
Bond failure – moisture contamination
Hormati et al – 50% decreased shear bond st
Hydrophilic primer ( HEMA & Maleic acid )dissolved in acetone – 3M Unitek.
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Hydrophilic Primer ( MIP ) S.J. Little Wood et al JO 2000
Compared the bond strength of bracket bonded with hydrophilic primer with conventional primer
Bond strength (6.43) was lower than conventional primer (8.71)
Bracket bonded with hydrophilic primer were 3.96 times more at risk of failure. www.indiandentalacademy.com
Pre primed brackets
ADVANTAGES:
Consistent quality of adhesive Reduced flash Adequate bond strength Less chances of contamination
Can be used in both direct & indirect tech. Both metal & ceramic brackets are available www.indiandentalacademy.com
Bonding Procedure
Cleaning
Enamel conditioning
- Acid etching - Crystal growth - Sandblasting - Laser etching Sealing Bonding www.indiandentalacademy.com
Bonding Procedure
Four steps 1.
Transfer
2.
Positioning
3.
Fitting
4.
Removal of excess
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Bonding
TRANSFER
Adhesive put on bracket base
Bracket placed on the tooth closed to the correct position www.indiandentalacademy.com
Bonding ď Ź
POSITIONING
ď Ź
Proper vertical and horizontal positioning ( eg Using placement scaler with parallel edges) www.indiandentalacademy.com
Bonding
FITTING
Bracket firmly pushed towards the tooth surface with one point contact www.indiandentalacademy.com
Bonding REMOVAL OF EXCESS
Gingival irritation
Plaque build up
Better esthetics
Prevents staining and discoloration www.indiandentalacademy.com
Bonding to Fluorosed teeth Dr.Veeresh
Bonding to the fluorosed teeth is difficult with conventional acid etching.
Aim – to evaluate the shear bond strength of the bracket to the fluorosed teeth by using a comb. of sandblasting & acid etching www.indiandentalacademy.com
Bonding to Fluorosed teeth
Group 1 – acid etching Group 2 – sandblasting Group 3 - acid etching followed by sandblasting Group 4 – sandblasting then acid etching Results Only group 4 – Bond strength slightly higher than optimum (8.1Mpa) www.indiandentalacademy.com
Curing Lights
Tungsten quartz halogen light
Argon laser
Xenon plasma arc light
Light emitting diode curing units ( LED )
Pulsed xenon plasma arc light www.indiandentalacademy.com
Halogen Tungsten Quartz Curing Light
Bulb quartz Filament Tungsten Gas Halogen
Selective filters – blue light ( 400-500 micron)
40 seconds per bracket 15 minutes – both arches www.indiandentalacademy.com
Halogen Tungsten Quartz Curing Light Disadvantages
Curing is time consuming
Light output < 1% of consumed electricity
Lifetime – 100hrs
High heat - degrades components of bulb www.indiandentalacademy.com
Argon laser
Introduced in the late 80’s &early 90’s
Promised to reduce the curing time dramatically
480 microns wavelength
Curing time 3 secs – per bracket 1 min – both arches
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Argon laser
KELSEY ,POWELL To equal bond strength of 40 sec exposure by conventional curing light, argon laser must cure for 10 seconds
Disadvantages
Laser unit large
expensive
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Xenon plasma arc light
Introduced in late 1990’s
Short exposure time at lower cost
Curing time – 3-5 sec per bracket
Higher intensity than conventional
Expensive – argon laser > xenon plasma > conventional light. www.indiandentalacademy.com
Comparison of efficiency of xenon plasma light and conventional light Sheldon Newman et al AJO 2001
Exposure time 40 secs – conventional curing light 3,6 & 9 secs – xenon plasma light Bond strength Xenon light > with longer exposure time To equal bond strength of conventional curing light the exposure time with xenon had to be 6 – 9 secs www.indiandentalacademy.com
Light emitting diode curing units Mills –1995
Instead of hot filament – Halogen bulb.
LED – junction of doped semi conductors.
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Light emitting diode curing units Advantages:
Lifetime 10, 000 hrs Requires no filters Resist shock and vibration Little power to operate Newer – GALLIUM NITRIDE ( LED ) 400500microns www.indiandentalacademy.com
Light emitting diode curing units Mills et al ( BJO 1997 ) Compared light source containing LED to Halogen units Concluded â&#x20AC;&#x201C; LED curing units cured composites to significantly greater depths when tested at 40 & 60 sec www.indiandentalacademy.com
Light emitting diode curing units ď Ź
Disadvantages
ď&#x192;&#x2DC;
Their technology is new to orthodontics, and the concept still is evolving.
ď&#x192;&#x2DC;
Their curing time is slower than plasma arc curing lights and some enhanced halogen lights. www.indiandentalacademy.com
Light emitting diode curing units Disadvantages Their batteries must be recharged.
They cost more than do conventional halogen lights.
They offer a relatively low intensity. www.indiandentalacademy.com
Polymerization of resin cement with LED curing unit
ď Ź
ď Ź
William Dunn & Louis Taloumis AJO sep 2002 Compared the shear bond strength of orthodontic brackets bonded to teeth with conventional halogen light and LED curing units . No diff in bond strength of orthodontic brackets bonded to teeth with conventional halogen light and LED curing units . www.indiandentalacademy.com
Light Emitting Diode Units Dr.Ravitej
1. 2.
3.
Aim - Shear Bond Strength Evaluation of three commercially Available Light Emitting Diode Units The 3 different LED sources used in the study Elipar Freelight (3M/ESPE) Bee Cool (Confident dental equipments, Bangalore) Apoza (Meghna and Co., Bangalore) www.indiandentalacademy.com
1. 2.
3.
3 different LED sources used in the study Elipar Freelight (3M/ESPE) Bee Cool (Confident dental equipments, Bangalore) Apoza (Meghna and Co., Bangalore)
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Study sample -- 70 non-carious extracted upper premolar teeth Divided into 7 groups of 10 each
Group I Elipar Freelight
Group II-IV Group V-VII Bee Cool (Confident) Apoza
Results Bond strength of G I and G IV samples fall in the optimal range. Bond strength values of other groups were suboptimal. www.indiandentalacademy.com
ď Ź
Group I sample (Elipar Freelight-10s, 3M/ESPE) can be considered most suitable
ď Ź
Group IV sample (Bee Cool-20s, Confident dental equipments, Bangalore) can also be considered appropriate
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References
Orthodontics current principles & techniques: Graber & Vanarsdall, 3rd Ed Philip’s science of dental materials 11th Ed Contemporary orthodontics: Proffit 3rd Ed Orthodontic Materials Scientific & Clinical Aspects: William A. Brantley,Theodore Eliades SEM Study & SBS measurement with 5% & 37% phosphoric acid - AJO-DO oct,1995 Wasundhara A. Bhad, Pushpa V. Hazarey, G.D.C.Nagpur www.indiandentalacademy.com
References
Air abrasion tech vs conventional acid etching tech.- AJO-DO Jan 2000- Wandela L. et al Laser etching of enamel for direct bondingAO,1993 no.1- Von Fraunhofer et al Clinical trials with crystal growth- AJO-DO Apr 1984 – Artun and Bergland crystal growth on outer enamel surface- AJO-DO March 1986- Maijer & Smith Thesis on Laser etching - Dr. Francis Thesis on Bonding to Fluorosed teeth Dr.Veeresh www.indiandentalacademy.com
References
Bond strength with various etching times on young perm teeth- AJO-DO Jul 1991- Wang & Chau Lu Effect of enamel etching time on bond strength & morphology- JCO Jan 1985- Wayne et al Lab.& clinical evaluation of self etching primer JCO Jan 2001- Robert A. Miller Variation in acid etch patterns with diff acids & etch time AJO-DO Jul 2001- Alastair Gardner et al www.indiandentalacademy.com
References
Clinical evaluation of bond failure rates with a new self etching primer- JCO Dec 2002Shadow Asgari et al Rapid curing of bonding with xenon plasma arc light - AJO-DO Jun 2001- Oesterle, Sheldon, Newman et al Evaluation of sealant in ortho bonding- AJO-DO Sep 1991- Wei Nan Wang Bond strength comparison of MIP- AJO-DO Sep 2002- Shane & Timothy www.indiandentalacademy.com
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