ADHESION OF DENTURE TOOTH PORCELAIN TO HEAT-POLYMERIZED DENTURE RESIN

Use of porcelain denture teeth may be desirable in many clinical situa tions, including implant-supported prostheses. However, lack of space because of frameworks often precludes the use of conventional retentio n by diatorics and pins. Adhesion of porcelain denture teeth to dentur e resin could also stiffen and possibly strengthen dentures and decrea se stain ingress between porcelain teeth and resin denture bases. Unli ke previous studies that investigated the bond between conventional fe ldspathic metal-ceramic porcelain and bis-GMA based composite resin, t his study investigated adhesion of denture tooth porcelain to polymeth yl methacrylate (PMMA). High-energy air abrasion, hydrofluoric acid et ching, and the use of a general purpose bonding agent resulted in an i mproved bond strength of heat-cured denture PMMA bonded to denture too th porcelain. Silane coating did not improve bond strengths, and conve n tional air abrasion was no more effective than polishing with 600-gr it silicon carbide. Storage in water and artificial aging substantiall y decreased bond strengths. The strongest bond strengths were achieved by a high energy-abrasion + etching + multiple purpose bonding-agent treatment, but a simpler etching + multiple purpose bonding-agent trea tment also produced reliable results. A laboratory technique was sugge sted. The role of surface treatment in the mechanism of adhesion was e xamined with scanning electron microscopy. High-energy abrasion produc ed a slightly more detailed initial topography than conventional air a brasion, but after etching, the high-energy topography became much mor e detailed. Surface topography alone did not account for all differenc es found.