Longitudinal study of pressed glass-ceramic inlays for four and a half years

Abstract

Statement of problem. Some restorative materials used in the posterior region of the mouth present conventional problems, such as microleakage, recurrent caries, wear, and poor color stability. Purpose. This study determined the reliability of the IPS Empress ceramic material for fabricating inlays and onlays in the posterior region of the mouth. Material and methods. A total of 125 IPS Empress pressed glass ceramic inlays were placed for 29 patients in a private practice. The restorations were observed for a period of 7 to 56 months, with a mean of 40.3 months. All inlays were constructed in the same dental laboratory and the restorative materials used according to the manufacturers' instructions. The restorations were evaluated clinically according to modified U.S. Public Health Service criteria at the time of insertion and at periodic recall appointments. Kaplan-Meier statistics were used to calculate survival rates. Results. Clinical evaluation revealed that pressed glass ceramic inlays, with the exception of four fractured restorations, were rated from Alpha to Bravo for each criteria. Marginal discoloration recorded the lowest percentage of alpha ratings (65.3%). The estimated survival rate after approximately a 4.5-year follow-up period was 95.63% (95% confidence interval; 90.77% to 99.95%). (J Prosthet Dent 1997;78:346-53.)