ABSTRACT
This study evaluated the effect of composite post placement and/or light-irradiation of dual-cure resin composite on adhesion to root canal dentin using the chemical activation mode of a 1-step self-etch dual-cure adhesive. Post spaces were prepared in extracted premolars. Root canal spaces were applied with Unifil Core EM Self-Etching Bond, which was chemically-polymerized, and then filled with Unifil Core EM with or without the placement of composite post. Half the specimens of each group were light-cured for 10 seconds and the other half were chemically-cured in darkness for 30 minutes. After 24 h storage, microtensile bond strengths (µTBS) at the coronal and apical regions were measured. When light-curing, placement of the composite post significantly reduced the µTBS to root canal dentin. On the other hand, when chemical-curing, there was no significant difference in µTBS between with and without placement of the composite post.
Subject(s)
Composite Resins/chemistry , Dental Materials/chemistry , Dental Pulp Cavity/ultrastructure , Dentin-Bonding Agents/chemistry , Dentin/ultrastructure , Post and Core Technique , Self-Curing of Dental Resins/methods , Adolescent , Dental Stress Analysis/instrumentation , Humans , Light-Curing of Dental Adhesives , Materials Testing , Microscopy, Electron, Scanning , Polymerization , Silanes/chemistry , Stress, Mechanical , Surface Properties , Tensile Strength , Time FactorsABSTRACT
The purpose of this study was to evaluate the dentin bonding durability of three HEMA-containing one-step self-etch adhesives after one-year water storage and to measure the amounts of their water sorption/solubility. OptiBond All-In-One (OP), Bond Force (BF) and Clearfil S³Bond (S³) were applied to the dentin surfaces according to manufacturers' instructions. Bond strengths to dentin were determined using µTBS test after water storage for 24 hours, six months, and one year. In addition, water sorption and solubility of the polymerized adhesives were measured. The µTBS of S³ and OP significantly decreased after one year. On the other hand, for BF there were no significant differences in µTBS between all storage periods. There were significant differences in water sorption and solubility among the adhesives (BF>S³>OP). The initial amounts of water sorption and solubility of the three adhesives did not affect their bonding durability to dentin.
