title: Immediate and delayed photoactivation of self-adhesive resin cements and retention of glass-fiber posts.
abstract: The aim of this study was to evaluate the effect of immediate and delayed photoactivation of self-adhesive resin cements (SARCs) on the retention of glass-fiber posts luted into root canals. Bovine incisors were endodontically treated, and post holes of 9 mm in depth were prepared. Fiber posts were luted using one of two SARCs, BisCem (Bisco Inc., Schaumburg, USA) or RelyX Unicem clicker (3M ESPE, Saint Paul, USA), or a regular (etch-and-rinse) resin cement (AllCem; FGM, Joinvile, Brazil). Photoactivation was performed immediately, or at 5 or 10 min after cementation. Root/post specimens were transversely sectioned 7 days after luting into 1-mm-thick slices, which were submitted to push-out testing in a mechanical testing machine. Bond strength data were analyzed by two-way ANOVA and Student-Newman-Keuls' method (α = 0.05). Immediate photoactivation resulted in the highest bond strength for Unicem. BisCem demonstrated higher bond strength values when photoactivated after a 10-min delay. Immediate photoactivation yielded the lowest bond strengths for AllCem, although no differences in bond strength were observed between photoactivation delayed by 5 and 10 min. In conclusion, the moment of resin cement photoactivation may affect the intraradicular retention of fiber posts, depending upon the resin cement used for luting.
authors.forename: André Luis
authors.initials: AL
authors.lastname: Faria-e-Silva
authors.forename: Aline Carvalho
authors.initials: AC
authors.lastname: Peixoto
authors.forename: Marcela Gonçalves
authors.initials: MG
authors.lastname: Borges
authors.forename: Murilo de Sousa
authors.initials: Mde S
authors.lastname: Menezes
authors.forename: Rafael Ratto de
authors.initials: RR
authors.lastname: Moraes
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002417:Cattle; D003188:Composite Resins / Q000737:chemistry; D017268:Dental Prosthesis Retention / Q000379:methods*; D003786:Dental Pulp Cavity / Q000187:drug effects*; D019232:Dental Restoration Failure; D003804:Dentin / Q000187:drug effects; D017220:Dentin-Bonding Agents / Q000737:chemistry; D005898:Glass / Q000737:chemistry*; D055115:Light-Curing of Dental Adhesives / Q000379:methods*; D008422:Materials Testing; D058105:Polymerization / Q000528:radiation effects; D011176:Post and Core Technique; D015203:Reproducibility of Results; D019279:Resin Cements / Q000737:chemistry*; D013997:Time Factors
chemical_list: C542562:BisCem cement; D003188:Composite Resins; D017220:Dentin-Bonding Agents; D019279:Resin Cements