IN-VITRO FLEXURAL FATIGUE LIMITS OF DENTAL COMPOSITES

The flexural fatigue test equipment developed was used to study the fa tigue behavior of dental restorative composites, using a ''staircase'' approach. Three commercial composites were tested after dry and wet s torage conditions. The findings indicate that the method is accurate a nd reliable, and that changes due to water sorption are clearly reflec ted: The flexural fatigue limit decreases after water sorption. From t he present results it seems that under environmentally controlled cond itions, the fatigue behavior is characterized by a well-defined fatigu e stress level above which the composites tested fail rapidly, and bel ow which they survive. (C) 1994 John Wiley and Sons, Inc.