Push-out bond strength between composite core buildup and fiber-reinforced posts after different surface treatments

Photomed Laser Surg. 2013 Jul;31(7):328-33. doi: 10.1089/pho.2013.3478. Epub 2013 Jun 11.

Abstract

Objective: The aim of this study was to evaluate the effects of different surface treatments on the pushout bond strength of fiber-reinforced posts to composite resin cores.

Materials and methods: Twenty-five translucent glass fiber posts were divided into five groups according to surface treatment methods as follows: an untreated control group, a group coated with silicated alumina particles (Co-Jet system, 3M ESPE, St. Paul, MN), and three groups undergoing surface preparation with erbium:yttrium-aluminum-garnet (Er:YAG) laser under three different power settings (150, 300, and 450 mJ at 10 Hz for 60 sec at 100 μs duration). After surface treatment, fiber posts were built up to a dual cure composite resin core. All of the specimens were set and sectioned perpendicularly along the long axis of the post using a saw. Two discs (thickness of 2 mm) were obtained from each post-core sample; finally, each group consisted of 10 samples. For artificial aging, the specimens were stored in water (37°C) for 24 h and subjected to thermal cycling (5000 cycles, 5-55°C, and 30 sec dwell time). Pushout tests were performed using a universal testing machine at a crosshead speed of 0.5 mm/min. The pushout pressure values were measured in MPa and analyzed using one way analysis of variance (ANOVA) and Tukey's honestly significant difference (HSD) post-hoc test (p<0.05). Fiber post surface images were obtained using a scanning electron microscope (SEM).

Results: The bond strength values ranged between 14,949 and 23,879 MPa. The lowest values were observed in the groups treated with the Er:YAG laser at 150 mJ. Irradiation by the Er:YAG laser at 450 mJ affected the bond strength significantly (p<0.05). After Co-Jet sandblasting, the bond strength increased relatively (19,184 MPa).

Conclusions: Er:YAG laser irradiation enhanced the bond strength of fiber-reinforced posts to composite resin cores depending upon the power applied; Co-Jet sandblasting also increased the bond strength.

Publication types

  • Comparative Study

MeSH terms

  • Composite Resins*
  • Dental Bonding*
  • Glass
  • Humans
  • In Vitro Techniques
  • Lasers, Solid-State*
  • Post and Core Technique*

Substances

  • Composite Resins
  • fiberglass