Microtensile bond strength of light- and self-cured adhesive systems to intraradicular dentin using a translucent fiber post

Oper Dent. 2005 Jul-Aug;30(4):500-6.

Abstract

This study evaluated the bond strength of a light- and self-cured adhesive system to different intraradicular dentin areas (cervical, middle and apical thirds). Twenty single-rooted teeth were instrumented and their roots were prepared to receive a #2 translucent fiber post (Light Post). The root canals were irrigated with 0.5% sodium hypochlorite for one minute, rinsed with water and dried using paper tips. The teeth were divided into two groups (n=10): Single Bond [SB] (light-cured) and Scotchbond Multi-Purpose Plus [SBMP] (self-cured). To avoid polymerization of the materials through the root lateral walls, the teeth were placed in a silicone mold and the adhesives applied with a thin microbrush according to manufacturer's instructions. The resin cement, Rely X ARC, was inserted into the root canals using Lentulo burs. The post was then placed and the light-curing procedure was carried out for 40 seconds (+/-500 mW/cm2). The roots were kept in a 100% relative moisture environment for 24 hours and stored in distilled water for an additional 24 hours. Each root was perpendicularly sectioned into 1-mm thick sections, resulting in approximately four slices per region. Dumbbell-shaped slices were obtained by trimming the proximal surfaces of each slice using a diamond bur until it touched the post. The bonded area was calculated, slices were attached to a special device and submitted to microtensile testing at 1 mm/minute crosshead speed. Data were analyzed using ANOVA and Tukey's test. The mean bond strength values (MPa) were: SBMP: cervical=10.8a, middle=7.9b%, apical=7.1bc; SB: cervical=8.1b, middle=6.0c, apical=6.9b. Significant differences were found between adhesive systems only for the cervical third. The cervical region showed higher mean bond strength values than the middle and apical regions (p<0.0001).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bisphenol A-Glycidyl Methacrylate / chemistry
  • Dental Bonding*
  • Dental Pulp Cavity / ultrastructure*
  • Dentin / ultrastructure*
  • Dentin-Bonding Agents / chemistry*
  • Humans
  • Materials Testing
  • Polyethylene Glycols / chemistry
  • Polymethacrylic Acids / chemistry
  • Post and Core Technique / instrumentation*
  • Resin Cements / chemistry
  • Root Canal Irrigants / chemistry
  • Root Canal Preparation
  • Sodium Hypochlorite / chemistry
  • Stress, Mechanical
  • Tensile Strength

Substances

  • Dentin-Bonding Agents
  • Polymethacrylic Acids
  • RelyX ARC
  • Resin Cements
  • Root Canal Irrigants
  • Scotchbond Multi-Purpose Plus
  • single bond
  • Polyethylene Glycols
  • Bisphenol A-Glycidyl Methacrylate
  • Sodium Hypochlorite