[A study of the adhesive resins used in adhesion bridges]

We suspected that the composition of stiffened adhesive resins may cause adhesion bridges to drop out. In this study, by using a scanning type electron microscope, we observed the breaking sides of the adhesive resin after the tension test. We also examined the surfaces of the resin that we cut and ground after it had hardened, and the surfaces of the adhesion bridges that dropped out.

1) RESULTS of the tension test. No significant differences between the adhesive resins were observed. We noticed no significant differences between the metal surface treatment methods. 2) Observations of the breaking side after the tension test. When we examined Panavia EX, we observed flaking of the metallic side and the tooth enamel. We noticed that the surface was smooth regardless of the method of preprocessing the metal. But the surface of the adhesive resin was bumpy, and we found bubbles of different sizes on the resin surfaces. When we examined Super-Bond C&B, we observed flaking of the metallic side and the tooth enamel, and the surfaces were smooth regardless of the method of preprocessing the metal. Unlike Panavia EX, however, we found various hollows, big and small, like the bubbles on the smooth surfaces of Super-Bond C&B. 3) Observations of the abrasive surface of stiffened adhesive resins. With an ambient temperature of 15 and 28 degrees, we found many minute hollows like bubbles on the abrasive surfaces of Panavia EX and Super-Bond C&B. 4) Observations of the surface of the bonding materials of the adhesion bridges which dropped out. We found bumpy surfaces on the adhesive resin which remained on the metallic side of the adhesion bridges, whichever position the adhesion bridges dropped out of.