Heat of polymerization of certain new and conventional restorative materials

A differential thermal analysis (DTA) for the heats of reaction and temperature rises produced during the setting of tooth coloured restorative materials

Differential thermal analysis (DTA) has been used to obtain the temperature rises produced during the setting of a range of tooth coloured restorative materials, which included silicates, glass ionomers and composites. These have been compared on the basis of the temperature rise per unit volume of material. Calibration of the areas under the reaction peaks (produced during this isothermal operation) to obtain heats of reaction is discussed and a method described. As for the temperature rises, values are given per unit volume of material. The results are compared with those reported in other studies from which DTA is seen to be a technique suited to the determination of these parameters and which might be considered for use a standard method.

Adhesion of restorative materials to teeth

A statistical evaluation was made of the effects of silver nitrate and citric acid tooth pretreatments on the adhesion, measured in vitro, of several direct-filling resin restorative materials for human and bovine dentin and enamel and of the significant interactions of the various factors.