title: Effect of laser irradiation and cavity disinfectant application on the microtensile bond strength of different adhesive systems.
abstract: OBJECTIVE
  The aim of this study was to evaluate the effect of two different cavity disinfection procedures (chlorhexidine gluconate-based cavity disinfectant and Er,Cr:YSGG laser irradiation) on the bond strength of two different types of adhesive systems (Adper Single Bond 2 [SB] and Clearfil SE Bond [SE]).
  
  
  METHODS
  Thirty human third molars were ground flat to expose midcoronal dentin. After the dentin surfaces were polished with 600-grit silicon carbide paper, the teeth were randomly assigned to six groups (n = 5) according to the cavity disinfection procedure and the adhesive resin: Group I, etch and rinse adhesive (SB); Group II, self-etch adhesive (SE); Group III, cavity disinfectant application (cavity cleanser) + SB; Group IV, cavity disinfectant application + SE; Group V, laser irradiation (Er,Cr:YSGG laser, 20 Hz; 0.75 W; 15% water, 15% air) + SB; Group VI, laser irradiation + SE. For each group, the composite crown was incrementally fabricated with a composite resin. Following storage in distilled water at 37 degrees C for 24 h, the bonded specimens were serially sectioned into rectangular beams (n = 32). Bond strengths were determined using a microtensile tester at a crosshead speed of 0.5 mm/min. Data were analyzed using two-way ANOVA, and multiple comparisons were performed using post hoc Duncan's test (p < 0.05).
  
  
  RESULTS
  Cavity disinfectant application and laser irradiation produced significantly higher bond strength values compared to the control group for SB. For SE, only laser irradiation improved the bond strength values compared to the control. There was a statistically significant decrease in the bond strength values of the specimens that were subjected to cavity disinfectant before SE application. The failure mode was mainly adhesive in all groups.
  
  
  CONCLUSIONS
  Cavity disinfectant application and laser irradiation may influence bond strength, depending on the adhesive system used. As a cavity-disinfecting procedure, laser irradiation might enhance the bond strength of etch and rinse and self-etch adhesive systems.
authors.affiliation: Baskent University, Faculty of Dentistry, Department of Conservative Dentistry, Ankara, Turkey. ccivelek@hotmail.com
authors.forename: Ciğdem
authors.initials: C
authors.lastname: Celik
authors.forename: Yonca
authors.initials: Y
authors.lastname: Ozel
authors.forename: Bora
authors.initials: B
authors.lastname: Bağiş
authors.forename: Selim
authors.initials: S
authors.lastname: Erkut
mesh_terms: D003513:Cycloheximide / Q000494:pharmacology*; D003737:Dental Cavity Preparation / Q000379:methods*; D003738:Dental Cements / Q000528:radiation effects*; D004202:Disinfectants / Q000494:pharmacology*; D004203:Disinfection / Q000379:methods; D006801:Humans; D066298:In Vitro Techniques; D007834:Lasers; D013718:Tensile Strength / Q000187:drug effects / Q000528:radiation effects
chemical_list: D003738:Dental Cements; D004202:Disinfectants; D003513:Cycloheximide