title: Effect of convergence angle on retention of resin-bonded retainers cemented with resinous cements.
abstract: BACKGROUND
  Poor retention is a common cause of failure for resin-bonded restorations.
  
  
  OBJECTIVE
  This study evaluated the effect of the convergence angle of tooth preparations on retention of resin-bonded restorations, luted with adhesive and conventional resinous cements.
  
  
  METHODS
  A total of 80 posterior retainers with four different tooth preparation angles were cemented with two different resinous cements, and retentive strength was measured.
  
  
  RESULTS
  The results indicated that (1) increased tapering of tooth preparations resulted in loss of retention and this variable was statistically significant for both cements used when convergence angles exceeded 10 degrees and (2) sandblasted nickel-chromium retainers, combined with adhesive resins, should provide sufficient retention for posterior resin-bonded fixed partial dentures.
authors.affiliation: Department of Fixed Prosthodontics, Aristotelian University, Thessaloniki, Greece.
authors.forename: A
authors.initials: A
authors.lastname: Sarafianou
authors.forename: N M
authors.initials: NM
authors.lastname: Kafandaris
mesh_terms: D000269:Adhesives / Q000737:chemistry; D002484:Cementation; D002858:Chromium Alloys / Q000737:chemistry; D001840:Dental Bonding; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D003779:Denture Design; D003781:Denture Retention; D016379:Denture, Partial, Fixed, Resin-Bonded; D006801:Humans; D008422:Materials Testing; D010710:Phosphates / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength; D019231:Tooth Preparation, Prosthodontic
chemical_list: D000269:Adhesives; D002858:Chromium Alloys; D010710:Phosphates; D019279:Resin Cements; C052304:Panavia EX