Different surface preparation techniques of porcelain repaired with composite resin and fracture resistance

BACKGROUND: Porcelain from prosthesis such as crown or bridge can be fractured if exposed to trauma; and, can be repaired at chairside using composite resin. AIM: To investigate the fracture resistance of few techniques of surface preparation in repairing fractured porcelain using composite resin. MATERIALS AND METHODS: Eighty samples of porcelain blocks were divided into 4 groups for different surface preparations, such as, Cimara repairing kit; porcelain etch kit containing hydrofluoric acid; Panavia F resin cement; and, sandblasting using aluminium oxide, before composite resin (Filtek Z250, 3M ESPE) was bonded to the prepared porcelain blocks. Twenty others samples in the control group comprised of pure porcelain blocks. The fracture resistance of each sample was tested using Instron machine (UK). RESULTS: With the exception of the group repaired using hydrofluoric acid (3.04±1.04 Mpa), all the other groups showed significant difference in the fracture resistance values when compared to the control group (3.05 ± 1.42 MPa) at P<0.05. CONCLUSIONS: Etching of the porcelain blocks with hydrofluoric acid holds promise in the repair of fractured porcelain with composite resin at chairside.