MARGINAL LEAKAGE OF DENTAL RESTORATIONS SUBJECTED TO THERMAL STRESS

The effects of thermal stress on the microleakage of dental restorations of varying ages were measured with radioisotope. Microleakage around one-week amalgam restorations was increased when the restorations were subjected to 500 temperature cycles. Three-month specimens exhibited good sealing ability which was not affected by the thermal cyclin. Amalgam restorations, which were inserted into cavities coated with a varnish, showed little or no marginal penetration at any time period, and the sealing qualities of these restorations were not impaired by thermal stressing. Silicate cement and the two types of restorative resins sealed the cavities with a considerable degree of efficacy over the three-month period of the study. The marginal adaptation was not impaired by thermal stress of the magnitude employed in this study. © 1969 The C. V. Mosby Company.