title: Effects of metal primers on the bonding of an adhesive resin cement to noble metal ceramic alloys after thermal cycling.
abstract: BACKGROUND
  Although the effectiveness of primers for resin bonding to noble alloys has been demonstrated, no effective clinical technique for bonding to noble metal ceramic alloys has been established.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the effects of metal primers on the shear bond strength of an adhesive resin to noble metal ceramic alloys after thermal cycling.
  
  
  METHODS
  Sixty-three disk-shaped specimens (10 × 2.5 mm) were cast from high-gold-content alloys (Super Metal W-85: W85 or IFK88 GR: IFK88), a high-palladium-content alloy (Super Metal N-40: N40), and an Ag-Pd-Cu-Au alloy (Castwell M.C.12: MC12). Smaller-sized disk-shaped specimens (8 × 2.5 mm) were fabricated with MC12. Bonding surfaces were finished with 600-grit SiC-paper and airborne-particle abraded with 50-μm alumina. Pairs of disks were primed (V-Primer: VP; ML Primer: ML; or Metaltite: MT) and bonded with an adhesive resin (Super-Bond C&B). The bond strengths were determined before and after 20,000 and 50,000 thermal cycles (n=7). Data were analyzed by using a 3-way ANOVA and the Bonferroni test (α=.05). Failure modes were determined by optical microscope and SEM observation.
  
  
  RESULTS
  Bond strengths to high-gold-content alloys with VP and MT significantly decreased after the thermal cycling (P<.001). Bond strengths to W85 (35.27 ±4.25 MPa) and IFK88 (33.57 ±3.56 MPa) after 50,000 thermal cycles obtained by ML were the highest (P<.001), and these groups showed combination failures. Bond strengths to N40 significantly decreased after 50,000 thermal cycles (P<.001), regardless of primers.
  
  
  CONCLUSIONS
  Shear bond strengths (SBS) to high-gold-content alloys were not degraded up to 50,000 thermal cycles when primed with ML. None of the primers evaluated was effective for high-palladium-content alloy.
authors: Fixed Prosthetic Clinic, Kagoshima University Medical and Dental Hospital, Kagoshima, Japan. minami@dent.kagoshima-u.ac.jp
authors: Hiroyuki
authors: H
authors: Minami
authors: Sadaaki
authors: S
authors: Murahara
authors: Shiro
authors: S
authors: Suzuki
authors: Takuo
authors: T
authors: Tanaka
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry; D001896:Boron Compounds / Q000737:chemistry; D017554:Carbon Compounds, Inorganic / Q000737:chemistry; D003300:Copper / Q000737:chemistry; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry*; D045662:Dental Etching / Q000379:methods; D006047:Gold Alloys / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D016876:Metal Ceramic Alloys / Q000737:chemistry*; D008689:Methacrylates / Q000737:chemistry; D008768:Methylmethacrylates / Q000737:chemistry; D010165:Palladium / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D033081:Shear Strength; D017655:Silicon Compounds / Q000737:chemistry; D012834:Silver / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013889:Thiouracil / Q000031:analogs & derivatives / Q000737:chemistry; D014227:Triazines / Q000737:chemistry
chemical_list: D001896:Boron Compounds; D017554:Carbon Compounds, Inorganic; D003738:Dental Cements; D006047:Gold Alloys; D016876:Metal Ceramic Alloys; C509517:Metaltite; D008689:Methacrylates; D008768:Methylmethacrylates; D019279:Resin Cements; D017655:Silicon Compounds; D014227:Triazines; C107059:V-Primer; D012834:Silver; D013889:Thiouracil; D010165:Palladium; D003300:Copper; C049495:Super-bond; D000537:Aluminum Oxide; C022088:silicon carbide