title: Different surface preparation techniques of porcelain repaired with composite resin and fracture resistance.
abstract: 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.
  
  
  OBJECTIVE
  To investigate the fracture resistance of few techniques of surface preparation in repairing fractured porcelain using composite resin.
  
  
  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.
authors.affiliation: School of Dental Sciences, Universiti Sains Malaysia Kubang Kerian, Kelantan, Malaysia.
authors.forename: Mohd Helmy Khalid
authors.initials: MH
authors.lastname: Abd Wahab
authors.forename: Wan Zaripah Wan
authors.initials: WZ
authors.lastname: Bakar
authors.forename: Adam
authors.initials: A
authors.lastname: Husein