Interfaces in Prosthodonticsshankariyerdds.com/AAID_Maxicourse_Asia/course_materials_Modul… · Amalgam • Annual failure rates 0 – 7.4% – (non gamma-2 and gamma-2 alloys upto

Interfaces in Restorative Dentistry

Exploring the RomanceThursday, March 19, 2009

A Long Lasting Romance• Neural Crest Cells - Ectomesenchyme

Thursday, March 19, 2009

A Long Lasting Romance• Reciprocal Interaction – papillary stimulation of

ectoderm – the enamel organ – the bud stage


A Long Lasting Romance• The Cap stage


A Long Lasting Romance• The Bell Stage


A Long Lasting Romance• Enamel – odontoblasts – dentine – the “DEJ”


A Long Lasting Romance• PDL – Cementum – root dentine


Tragedy – The Break - Up• Agenesis, Oligodontia, Microdontia


Tragedy – The Break - Up• Amelogenesis imperfecta


Tragedy – The Break - Up• Caries


Tragedy – The Break - Up• Trauma


Tragedy – The Break - Up• Periodontitis


Evolution of ProsthodonticsReviving the Romance

• Restorative Dentistry


The Restorative Interface

Review of the Clinical Survival of Direct and Indirect Restorations in

Posterior Teeth


Amalgam• Annual failure rates 0 – 7.4%

– (non gamma-2 and gamma-2 alloys upto 20years)– Cross-sectional data – better survival than composites

Summit et al. The performance of bonded vs pin-retained complex amalgam restorations. A five-year clinical evaluation, J Am Dent Assoc 2001;132:923-931

Wilson NHF, Wastell DG, Norman. Five-year performance of high-copper content amalgam restorations in multiclinical trial of a posterior composite, J of Dentistry 1996;24:203-210


Amalgam• Annual failure rates 0 – 7.4%

– (non gamma-2 and gamma-2 alloys upto 20years)– Cross-sectional data – better survival data than composites

Modes of Failure:– Secondary caries– Bulk and tooth fracture– Cervical overhang– Marginal ditching


Direct Posterior Composites• Annual failure rates 0 – 9 %Modes of failure: - Insufficient wear resistance (pre 1990) - Marginal opening with secondary caries - Fracture of the restorations - Marginal deterioration - Discoloration and wear

“Despite improvements in the formulation of new bonding agents with enhanced marginal adaptation and bond strengths, a perfect marginal seal is still not achievable” Buonocore Memorial Lecture – Reinhard Hickel, Operative Dentistry 2004;29:481-508


Posterior Composites• Interface contamination

– Saliva and Blood


Posterior Composites• Interface contamination

– Saliva and Blood “Salivary contamination had no adverse effect on the

shear bone strength of One-step total-etch adhesive after blot dried, washed or re-etched with phosphoric acid. Salivary drying < strength. Clearfil SE required only reapplication of primer”1

1.Park J, Lee KC. The Influence of Salivary contamination on Shear Bond strength of Dentin Adhesive Systems, Operative Dentistry 2004,29:437-442

Taskonak B, Sertgoz A. Shear bond strengths of saliva contaminated “one-bottle” adhesives, J Oral Rehabilitation 2002;29:559-564


Amalgam vs. Posterior Composites


Amalgam vs. Posterior Composites• Insurance Claim Database results:

– 207,558 amalgams – 94% survival – 5 years– 93,195 direct composites – 93% survival– Survival dropped from 92% - 60% at 7 years when

patients changed dentists

Bogacki et at. Survival analysis of posterior restorations using an insurance claim database, Operative Dentistry 2002;27:488-492


Ormocers(Organically Modified Ceramics)

• Annual failure rates 0-12.7%Modes of failure:– Polymerization shrinkage– Wear– Lower bond strenghts

Lopes LG et al. Clinical evaluation of two “packable” posterior composite resins: Two-year results, Clin Oral Investigations 2003;7:123-128


Compomers• Annual failure rates 0 – 3.3% (at 3 years)1

Stronger than microfilled composites2

Modes of Failure:– Inferior wear rate– Unknown long term behavior

1. Jedynakiewicz NM, Martin N & Fletcher JM. A clinical evaluation of a posterior compomer restorative at 3 years, J Dental Res 2002;81:52

2. Manhart J et al. Flexure mechanical properties of compomer materials J Dental Res 2001;80:203


Glass IonomersART restorations

• Annual failure rate – 33% Failure Modes: - low mechanical strength - secondary caries

Frencken JE, Makoni F, Sithole WD. Atraumatic restorative treatment and glass ionomer sealants in a school oral health programme in Zimbabwe: Evaluation after 1 year, Caries Research 1996;30:428-433


Indirect Posterior Restorations


Indirect Posterior RestorationsHierarchy of performance and longevity Cast Gold Inlays and Onlays –best longitudinal data CAD/CAM Ceramic Inlay and Onlays Ceramic Inlays and onlays Composite Inlays and Onlays

Annual failure rates: upto 10%(composites) Van Nieuwenhuysen et al. Long-term evaluation of extensive restorations in permanent

teeth, Journal of Dentistry 2003;31:395-405


Luting Interface• Provisional

– Zinc Oxide Eugenol (Tempbond,TempCem,Zone)- Very reliable- Interferes with PMMA- Does not interfere with bonding of composites with

newer multipurpose bonding agents*

* Leirstar J, NordbØ. The effect of zinc oxide eugenol on the shear bond strength of a commonly used bonding system, Dental Traumatology 2000;16:265



Eugenol free cements (Tempbond NE, Zone NE, Fregenol)– Ability to reline acrylic provisionals– Lowest retention for restorations– Preferred for implant FPD retrievability1

1. Michalalis KX, Pissiotis AL, Hirayama H. Cement failure loads of 4 provisional luting agents used for the cementation of implant-supported fixed partial dentures, Int J Oral Maxillofac Implants 2000;15:545-549



Resin based cements(Improv, Olympian, Implacem) - poor adhesion to tooth structure and provisional materials1

- longer setting time1

- Too retentive for implant FPDs2

“Insufficient data available for predictable usage”

1.Personal experience 2. Michalalis KX, Pissiotis AL, Hirayama H. Cement failure loads of 4 provisional luting agents used for the

cementation of implant-supported fixed partial dentures, Int J Oral Maxillofac Implants 2000;15:545-549


The Definitive Luting Interface• Zinc Phosphate

+ Longest track record > 100 years+ Excellent compressive strength+ Good film thickness+ Economical and good working time- Technique sensitive- Mild solubility- Poor tensile strength


The Definitive Luting Interface• Glass Ionomers(GC, Shofu)• Poly Carboxylates(Durelon)

+ Chemical Adhesion+ Fluoride release?– Water solubility– Compressive strengths1

1. Tyas MJ. Milestones in Adhesion: glass ionomer cements, J Adhes Dent 2003;5:259-66


The Definitive Luting InterfaceResin modified Ionomers(Rely X, Fujiplus, Fujicem)Compomers (Principle)+ good strength+ quick set, easy clean up+ fluoride release?- Hygroscopic expansion?1,2

1. Sindel J, Frankenberger R, Kramer N, Petschelt A.Crack formation of all-ceramic crowns depdendent on different core build-up and luting materials. J Dent 1999;27:175

2. Snyder MD, Lang BR, Razzoog ME. The efficacy of luting all-ceramic crowns with resin-modified glass ionomer cement. J Am Dent Assoc 2003;134:609-12


The Definitive Luting Interface Resin cements+ best strength+ good mechanical properties1

+ ability to work with different substrates- Technique sensitive- Breakdown of catalyst – unpredictable optical

properties

- 1. Fonseca et al.Comparison of the tensile bond strengths of cast metal crowns luted with resin cements J Oral Rehab 2004;31:1080-4


Documents

Interfaces in Prosthodonticsshankariyerdds.com/AAID_Maxicourse_Asia/course_materials_Modul… · Amalgam • Annual failure rates 0 – 7.4% – (non gamma-2 and gamma-2 alloys upto