title: Repair strength of etched vs silica-coated metal-ceramic and all-ceramic restorations.
abstract: The purpose of this in vitro study was to examine shear bond strengths of composite resin to metal-exposed porcelain-fused-to-metal (PFM) and all-ceramic restorations after silica coating or etching with 5% hydrofluoric acid (HF). Specimens were fabricated for each of the following groups: two all-ceramic materials [a feldspathic porcelain (Vita Mark II) and a leucite-reinforced glass-ceramic (IPS Empress)], and one noble metal-ceramic (Orplid Keramik I alloy; Vita VMK 68 N felspathic veneer ceramic). These groups were repaired with resin composites after different pretreatment methods. In one metal-ceramic subgroup the surface exhibited a 50% metal and 50% ceramic exposure. In the silica-coating groups, the specimen surfaces were air abraded with silica acid-modified Al2O3 (CoJet Sand) and treated corresponding to the porcelain repair with resin composite. For control groups, the surfaces were etched with 5% HF for 60 seconds and treated in the same way as the silica-coated groups. After 24 hours of storage (distilled water, 37 degrees C) and an additional 24 hours of thermocycling (1150 x 5 degrees C/55 degrees C) the specimens were debonded using a shear bond strength test (n = 15). In all groups the silica coat repair achieved equal or significantly higher bond strengths than did the etching technique (p < 0.05, Mann-Whitney U test). In the metal-exposed group, the mean bond strength increased from 7.3 MPa to 16.3 MPa following the silica-coat repair. Results indicated that silica coating represents a suitable treatment for the intraoral repair of the materials tested in the present study.
authors.affiliation: Policlinic for Operative Dentistry and Periodontology, University of Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Frankenberger
authors.forename: N
authors.initials: N
authors.lastname: Krämer
authors.forename: J
authors.initials: J
authors.lastname: Sindel
mesh_terms: D000134:Acid Etching, Dental; D000538:Aluminum Silicates / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry*; D003722:Dental Alloys / Q000737:chemistry; D001840:Dental Bonding; D003776:Dental Porcelain / Q000737:chemistry; D017269:Dental Prosthesis Repair; D006047:Gold Alloys / Q000737:chemistry; D006801:Humans; D006858:Hydrofluoric Acid / Q000737:chemistry; D008422:Materials Testing; D016876:Metal Ceramic Alloys / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry; D017680:Potassium Compounds / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D018709:Statistics, Nonparametric; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
chemical_list: D000538:Aluminum Silicates; D003188:Composite Resins; D003722:Dental Alloys; D006047:Gold Alloys; C075815:IPS-Empress ceramic; D016876:Metal Ceramic Alloys; D017680:Potassium Compounds; C082340:Vita Mark II; D014867:Water; D003776:Dental Porcelain; C016447:feldspar; C078519:leucite; D010984:Platinum; D012822:Silicon Dioxide; C047040:Vita VMK 68; D006858:Hydrofluoric Acid