Pulpal responses to various dentin bonding systems in dentin cavities.

The purpose of this study was to investigate pulpal response and bacterial invasion associated with five dentin bonding systems placed in cavities without an enamel margin. Two hundred and twenty-four dentin margin cavities were created by removing the surrounding marginal enamel of class V cavities in monkey teeth. These cavities were restored with a resin composite using various current dentin bonding systems. All of the dentin bonding systems showed odontoblastic layer changes to varying degrees, and slight to moderate inflammation at the initial stage. With the lapse of time, the degree of inflammation tended to decrease markedly, except for those cases in which bacteria were present. The result of SA/Photo Bond corresponded to that of the glass ionomer cement (negative control). Accordingly, this study suggests that a good bond and adaptation between resin and dentin should be obtained for eliminating pulpal irritation, even in the dentin cavity.