Effect of laser application on microtensile bond strength of an orthodontic adhesive to water-aged composite

Niger J Clin Pract. 2020 Jan;23(1):18-25. doi: 10.4103/njcp.njcp_318_19.


Aim: This study evaluated the microtensile bond strength (MTBS) of an orthodontic adhesive to water-aged composite surfaces using different surface treatments.

Subjects and methods: Twelve composite blocks (10 mm × 10 mm × 5 mm) were fabricated and randomly divided into two groups. Half of the specimens were stored in distilled water for 1 day, and the other specimens were stored for 30 days. The specimens were randomly assigned to six groups according to surface treatments (n = 15): Group 1, control (no treatment); Group 2, phosphoric acid; Group 3, diamond bur; Group 4, diamond bur + phosphoric acid; Group 5, laser; and Group 6, laser + phosphoric acid. One coat of orthodontic adhesive was bonded to one surface of composite blocks, and a microhybrid composite resin was bonded to the surfaces via a Teflon mold. Bond strength was evaluated using an MTBS test. Surface topography was evaluated using scanning electron microscopy (SEM) analysis. The data were analyzed using one-way analysis of variance, Tamhane post-hoc test, and independent sample t-tests (P < 0.05).

Results: Bond strength values tended to decrease in all groups (with the exception of Group 2) after storage in water for 30 days (P < 0.05). Laser and diamond bur application (with or without phosphoric acid) enhanced the bond strength.

Conclusions: An Er,Cr:YSGG laser application may be a feasible alternative to diamond bur for enhancing the bond strength of orthodontic adhesive to composite resin.

Keywords: Composite; laser; microtensile bond strength; orthodontic adhesive.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Composite Resins / chemistry*
  • Composite Resins / therapeutic use
  • Dental Bonding*
  • Dental Cements / chemistry*
  • Dental Stress Analysis
  • Humans
  • Lasers, Solid-State / therapeutic use*
  • Materials Testing
  • Microscopy, Electron, Scanning
  • Phosphoric Acids / chemistry
  • Shear Strength
  • Surface Properties
  • Tensile Strength*
  • Water / chemistry*


  • Composite Resins
  • Dental Cements
  • Phosphoric Acids
  • Water
  • phosphoric acid