title: Effect of femtosecond laser treatment on the shear bond strength of a metal bracket to prepared porcelain surface.
abstract: OBJECTIVE
  The aim of this study was to investigate the effects of femtosecond laser treatment (Group FS) on the shear bond strength (SBS) of a metal bracket to prepared porcelain surface, and to compare it with other surface treatment techniques [50 μm Al2O3 sandblasting (Group SB), 9.6% hydrofluoric acid gel (Group HF), and neodymium-doped yttrium aluminium garnet (Nd:YAG laser) (Group NY)].
  
  
  BACKGROUND
  Because of the increasing number of adult patients in current orthodontic practice, achieving sufficient bond strength of composite resin to porcelain restorations without bond failure during the treatment is a challenge for orthodontists.
  
  
  METHODS
  In total, 80 glazed feldspathic porcelain samples were prepared and randomly assigned to four groups of 20. Treated surfaces were treated with a silane agent. Brackets were bonded to porcelain samples. The specimens were stored in distilled water for 24 h and then thermocycled for 500 cycles between 5° and 55°C. The SBS of the brackets was tested with a universal testing machine at a crosshead speed of 1 mm/min, until bonding failure occurred. The data were analyzed statistically using analysis of variance (ANOVA) and Tamhane multiple comparisons tests. The results of ANOVA indicated that the SBS values varied according to the surface treatment method (p<0.001).
  
  
  RESULTS
  Results of the Tamhane post-hoc tests indicated that the bond strength in Group NY (5.11±1.53) was significantly lower than the other groups (p<0.05). There were no statistically significant differences among Groups SB (9.07±3.76), HF (9.09±3.51), and FS (11.58±4.16) (p=0.28).
  
  
  CONCLUSIONS
  The results of this study showed that FS treatment produced high SBS of the processes assessed; therefore, it appears to be an effective method for bonding orthodontic metal brackets to prepared porcelain surfaces.
authors: 1 Department of Prosthodontics, Faculty of Dentistry, University of Abant Izzet Baysal , Bolu, Turkey .
authors: Yusuf Ziya
authors: YZ
authors: Akpinar
authors: Celal
authors: C
authors: Irgin
authors: Tevfik
authors: T
authors: Yavuz
authors: Muhammed Ali
authors: MA
authors: Aslan
authors: Hamdi Sukur
authors: HS
authors: Kilic
authors: Aslihan
authors: A
authors: Usumez
mesh_terms: D001840:Dental Bonding; D045662:Dental Etching / Q000379:methods*; D003776:Dental Porcelain; D053844:Lasers, Solid-State; D028022:Low-Level Light Therapy; D016910:Orthodontic Brackets; D033081:Shear Strength / Q000528:radiation effects
chemical_list: D003776:Dental Porcelain