title: Reasons for Retreatment of Amalgam and Composite Restorations among the Patients Referring to Tabriz Faculty of Dentistry.
abstract: OBJECTIVE
  Retreatment of existing restorations not only requires a lot of money and time but also there is a danger of weakening tooth structure and irritating the pulp. Since awareness of the reasons for the retreatment of teeth will save the teeth from possible future failure, the aim of this study was to assess the reasons for retreatment of amalgam and composite restorations in patients referring to Tabriz Faculty of Dentistry.
  
  
  METHODS
  In this descriptive study, the subjects had previously received an amalgam or a composite restoration in the Operative Department by dental students and were judged to need retreatment in their second visit. A total of 300 defective teeth were selected by simple random sampling method. The data was collected through examination and questionnaires and analyzed using chi-square test.
  
  
  RESULTS
  There was a statistically significant association between the type of the restorative material and the reason for retreatment (p=0.001).
  
  
  CONCLUSIONS
  Although the reasons for the retreatment of amalgam and composite restorations were different, recurrent caries was the main reason for the retreatment for both restorative materials.
authors.affiliation: Assistant Professor, Department of Operative Dentistry, Faculty of Dentistry, Tabriz University of Medical Sciences, Iran.
authors.forename: Soodabeh
authors.initials: S
authors.lastname: Kimyai
authors.forename: Masomeh
authors.initials: M
authors.lastname: Mehdipour
authors.forename: Siavash
authors.initials: S
authors.lastname: Savadi Oskoee
authors.forename: Parnian
authors.initials: P
authors.lastname: Alizadeh Oskoee
authors.forename: Armin
authors.initials: A
authors.lastname: Abbaszadeh
keywords: Amalgam; composite; failure; replacement; retreatment