Laboratory evaluation of shear bond strength of porcelain repair methods

Introduction: porcelain fracture is a relatively common problem in clinical dental practice. various methods have been proposed for repairing porcelain fractures including direct composite resin repair or construction of a porcelain laminate veneer and its cementation with a resin cement. evaluation of shear bond strength of porcelain repair methods was the purpose of this study.methods: twenty feldspathic porcelain discs (10 mm in diameter) were fabricated. the samples underwent air-born abrasion with an aluminum oxide and etching with hf, and were then ultrasonically cleaned and randomized into two groups: 1- repair with porcelain disc (7 mm in diameter) with light cure cement (choice 2); and 2- repair with resin composite (clearfil ap-x). we measured the shear bond strength of the samples by zwick roll at 0.5 mm/min crosshead speed.results: the resin composite group had the highest shear bond strength (12.91 mpa). we found no significant differences between the choice and composite groups (p=0.970).conclusions: our findings indicate that resin composite yields acceptable shear bond strength to be used in porcelain repair.