Influence of cavity dimensions, insertion technique and adhesive system on microleakage of Class V restorations.
BACKGROUND
The authors evaluated the influence of cavity dimensions, insertion technique and adhesive system on microleakage of Class composite restorations.


METHODS
The authors prepared cylindrical cavities with enamel margins of 3-millimeter diameter by 1-mm depth or 6-mm diameter by 2-mm depth on the labial surface of bovine incisors. They defined experimental groups (n = 15) according to cavity size, insertion technique (bulk or incremental) and adhesive system applied (Single Bond, 3M ESPE, St. Paul, Minn., or Excite, Ivoclar Vivadent, Amherst, N.Y.). They restored preparations with Tetric Ceram (Ivoclar Vivadent). After 36 hours' storage in distilled water at 37 C, specimens were submitted to microleakage using 50 percent silver nitrate as tracer. Teeth were sectioned twice and dye penetration on the axial wall was determined in millimeters.


RESULTS
The authors analyzed the data using analysis of variance/Tukey test (a = .05). For large restorations, the use of Single Bond resulted in higher microleakage than Excite (1.56 +/- standard deviation [SD] 0.26 mm and 0.63 +/- SD 0.56 mm, respectively; P < .001), whereas for small restorations there was no statistical difference between adhesives (Excite: 0.47 +/- SD 0.28 mm; Single Bond: 0.46 +/- SD 0.28 mm).


CONCLUSIONS
The choice of adhesive system influenced microleakage only for large restorations. Incremental insertion of the composite did not affect dye penetration.


CONCLUSIONS
Microleakage of composite restorations cannot be predicted only on the basis of the restorations' dimensions. In large restorations, it also depends on the choice of adhesive system, whereas in small restorations, the adhesive used does not seem to be an influential factor. Incremental insertion did not seem to reduce restorations' microleakage.
Costa Pfeifer
Carmem Silvia
CS
University of São Paulo, School of Dentistry, Department of Dental Materials, Brazil.
Braga
Roberto Ruggiero
RR
Cardoso
Paulo Eduardo Capel
PE
D000134:Acid Etching, Dental; D000818:Animals; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D002417:Cattle; D003188:Composite Resins / Q000737:chemistry*; D003737:Dental Cavity Preparation / Q000379:methods*; D003743:Dental Enamel / Q000033:anatomy & histology*; D003763:Dental Leakage / Q000145:classification*; D003793:Dental Restoration, Permanent / Q000145:classification / Q000379:methods*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D007180:Incisor; D008689:Methacrylates / Q000737:chemistry; D010756:Phosphoric Acids / Q000737:chemistry; D016622:Silver Staining; D013696:Temperature; D014867:Water / Q000737:chemistry
D003188:Composite Resins; D017220:Dentin-Bonding Agents; C420130:Excite cement; D008689:Methacrylates; D010756:Phosphoric Acids; C121818:Tetric ceram; C115612:single bond; D014867:Water; D017438:Bisphenol A-Glycidyl Methacrylate