ABSTRACT
Adhesion is becoming more and more important in many situations in dentistry. Effective adhesion retains restorative dental materials at proper positions of tooth structure, solves the problem of leakage around restorations, and, consequently, improves their performances. Treatment of ceramic surfaces with chemicals such as silane coupling agents or hydrogen fluoride has been proposed, but the adhesion has not been improved enough for practical applications. The most important but difficult requirement for dental adhesives is to maintain the performance in water for a long period of time, and we found that even methacrylate monomers 11–14 that showed high adhesion in air were not suitable in water. Some possible reasons of low adhesiveness of calcium metaphosphate ceramic (CMP) are as follows: CMP is not providing thorough wetting with adhesives; functional groups or atoms, probably associated with adhesion, are not readily accessible on the surface; and total surface area is insufficient.
