title: Microtensile bond strength of resin cement to a feldspathic ceramic.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the microtensile bond strength of resin cement to a feldspathic ceramic after treating the surface with (a) hydrofluoric (HF) acid, (b) air abrasion, (c) Er:YAG laser irradiation, (d) Nd:YAG laser irradiation, and (e) HF acid etching after either air abrasion or laser irradiation.
  
  
  BACKGROUND
  It is unknown whether the laser application or its combination with another treatment method can be used as a tool to roughen the surface of a feldspathic ceramic in order to increase the bond strength between the resin cement and ceramic surface.
  
  
  METHODS
  Forty feldspathic ceramic blocks (Ceramco(TM)) were prepared and divided into eight equal groups (n = 5) according to the following surface treatments: no treatment; etching with 9.5% HF acid; air abrasion with 50 μm Al(2)O(3); Er:YAG laser irradiation; Nd:YAG laser irradiation; air abrasion plus acid etching; Er:YAG laser plus acid etching; and Nd:YAG laser plus acid etching. After surface treatment, a silane-coupling agent and resin cement (Panavia F(TM)) were applied to each block. After storing for 24 h at 37°C and thermocycling between 5°C and 55°C for 1000 cycles, the microtensile bond strength of each specimen was measured.
  
  
  RESULTS
  The highest bond strength was obtained from HF acid etching. HF acid etching after each laser irradiation significantly increased the bond strength (p < 0.05). However, HF acid etching after air abrasion decreased bond strength when compared to air abrasion alone.
  
  
  CONCLUSIONS
  HF acid etching is the most effective surface treatment method for a feldspathic ceramic. However, laser irradiation with either the Er:YAG or Nd:YAG laser is not an adequate method for improving the bond strength of Panavia F. The laser application should be combined with HF acid etching.
authors.affiliation: Department of Prosthodontics, School of Dentistry, University of Atatürk, Erzurum, Turkey. samilakyil@hotmail.com
authors.forename: Musa Şamil
authors.initials: MŞ
authors.lastname: Akyıl
authors.forename: Asude
authors.initials: A
authors.lastname: Yılmaz
authors.forename: Funda
authors.initials: F
authors.lastname: Bayındır
authors.forename: Zeynep Yeşil
authors.initials: ZY
authors.lastname: Duymuş
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D020906:Air Abrasion, Dental / Q000379:methods; D000704:Analysis of Variance; D001840:Dental Bonding / Q000379:methods; D003764:Dental Materials / Q000737:chemistry / Q000627:therapeutic use; D003776:Dental Porcelain / Q000737:chemistry* / Q000627:therapeutic use; D003799:Dental Stress Analysis; D006801:Humans; D006858:Hydrofluoric Acid / Q000737:chemistry / Q000627:therapeutic use; D066298:In Vitro Techniques; D028022:Low-Level Light Therapy / Q000379:methods; D008422:Materials Testing / Q000379:methods*; D019279:Resin Cements / Q000737:chemistry* / Q000627:therapeutic use; D013718:Tensile Strength
chemical_list: D003764:Dental Materials; C438843:Panavia-Fluoro; D019279:Resin Cements; D003776:Dental Porcelain; C058233:Ceramco; D006858:Hydrofluoric Acid