Microleakage and marginal adaptation of composite resin restorations.

It has been shown that the use of a sealant offers no advantage with respect to the retentive strength of a composite resin restoration. However, for the improvement of marginal seal and adaptation, the present findings indicate that enamel etching and the application of a sealant, in conjunction with use of a cavity geometry which reduces shrinkage strain, are absolute necessities.

[Adpatation and marginal fit of thixotropic composites and syringe system composites. In vitro findings]. / Adaptation und Randschluss von thixotropen Komposits und Spritzkapselsystemen, In-vitro-Befunde.

In a dye penetration test and a scanning electron microscopic evaluation MOD-restorations made of a thixotropic material (ZKP-A-5(2)) and of two syringe system composites (Concise-Capsule-Composite3, Compocap-S4) were investigated with respect to microleakage and marginal adaptation. These materials did not reveal better marginal micromorphology than a comparable two-paste composite system (Concise3); Compocap-S showed markedly less microleakage. The quality of marginal adaptation, however, was improved to 52% when a low viscosity sealant (ZKP-A-2(2), Concise Enamel Bond3) was applied before insertion of the restorative. A sealant pretreatment is therefore compulsory in thixotropic and syringe packed composites as well. The perfection reached with these composite brands is equal to that of adhesive restorations made of Concise or Adaptic5 [6,7]. Restorations performed with new, complete composite systems (Nimetic6, GC's Epolite 100/Epobond7) revealed moderate results when compared to standard materials like Concise or Adaptic [6,7].

[In vitro evaluation of the adaptation and quality of the margins in various composite systems]. / Constatations faites in vitro à propos de l'adaptation et de la qualité des joints marginaux de différents systèmes de composites.

Microleakage and marginal adaptation of different composite brands (Epoxydent, Restodent, Cosmic) in conventional and adhesive MOD-cavities have been investigated in an in vitro dye-penetration and scanning electron microscope study. The results were compared to those of a standard composite brand (Adaptic). Unrelated to the type of cavity and enamel etching procedures Epoxydent and Restodent revealed moderate results only. When the use of a sealant was omitted prior to bulk placement Cosmic showed the best adaptation. Priming (Cosmic Bond) was found to impede microleakage but not to influence marginal adaptation. The superiority of the adhesive restorations that had been performed with the Adaptic and the Concise system [4] is a result of the combination of these composite materials with a sealant and the new cavity design.

Endosteal oral implantology: two-year results of mobility and hysteresis measurements; A human study.

Clinical experience with tooth mobility measurements for assessment of periodontal health was employed in evaluating endosteal implant status. Mobility and hysteresis measurements of 14 implants in 11 patients were carried out regularly during a 2-year period. Immediate postsurgical implant post displacement was 5 hundreths of a millimeter (5.10(-2) mm). After 1, 6, and 24 months, mobility had increased to 13, 21, and 54.10(-2) mm respectively. Viscoelastic recoil patterns were recognized as diagnostic indicators of profound changes in the biophysical properties of periimplant environment.

[Follow-up studies on 15-month-old adhesive fillings]. / Nachkontroll von 11/4jährigen Adhäsivfüllungen

Clinically, 450 Adhesive Restorations have been reexamined 15 months after insertion. Several of these restorations were also evaluated by SEM. The principles of cavity preparation for adhesive fillings deviate from those postulated by G.V. Black. They aim at a micromethanical retention of the restorative material to the tooth structure. A considerable amount of sound tooth structure can be saved. The combination of cavity design with enamel conditioning and the use of a low viscosity sealant prior to the insertion of the composite (Caulk Nuva System) resulted in restorations showing no microleakage and a perfect marginal adaptation. Their retentive strength seems to be sufficient as well as the durability of their excellent marginal properties. Pulpal responses to the application of etching agents were avoided by covering the dentin with an acid resistant base. Splinting of teeth using a strictly adhesive method without cavity preparations failed in more than 50%. The high rate of composite discoloration (43%) was probably due to factors inherent in the restorative material itself.

[The development of the perfectly adapted MOD composite filling material with tight marginal fitting in vitro findings]. / Die Entwicklung der perfekt adaptierten, randspaltfreien MOD-Kompositfüllung, In-vitro-Befunde

Class II Adhesive Restorations have been realized with composites under laboratory conditions. They show a perfect marginal adaptation and no microleakage at the tooth/restoration interface. These properties were obtained a) with a new cavity preparation, b) by application of a low viscosity sealant prior to the placement of the bulk of the composite material. The Adhesive Restoration compared favorably with conventionally prepared restorations. Nevertheless, enamel conditioning with acid and the use of a low viscosity sealant in conventionally prepared class II cavities resulted also in some improvement of marginal adaptation.