[The marginal adaptation of Cerec-Dicor-MGC restorations with dentin adhesives]

Dicor MGC Cerec inlays were placed in 53 teeth clinically and in 24 extracted teeth. Both main groups were subdivided into the following four test subgroups: 1. monofunctional dentin adhesive without linings. 2. bifunctional dentin adhesive without linings. 3. monofunctional dentin adhesive with linings. 4. bifunctional dentin adhesive with linings. The marginal adaptation of the occlusal surfaces of the restorations placed clinically was evaluated from replicas using the scanning electron microscope at x 200 magnification. In contrast, the marginal adaptation of all the restored enamel surfaces and the disto-cervical dentinal margins of the restorations placed in the extracted teeth were similarly evaluated. These margins were examined before and after thermomechanical stressing. The restorations were stressed 120,000 times at 300 cycles of 5-55-5 degrees C, chemically degraded by immersion in ethanol of 75% for 20 h and brushed for 30 min with a toothbrush at 1,96 N load. The in-vitro restorations were also subjected to dye penetration tests. The percent "excellent margin" recorded along the enamel-composite interface of the occlusal surfaces of the clinically placed restorations varied between 83.6 and 88.2%. The corresponding scores for the in-vitro specimens were at least 95% before and 90% after the thermomechanical and chemical stressing. The bifunctional dentin adhesive "Prisma Universal Bond 2" had a 93.6% "excellent margin" along the dentin-composite margin before stressing which decreased to 84.4% after stress. These scores were not significantly different.