Comparison of Classic and Metal Reinforced Maxillary Acrylic Complete Dentures Fracture Resistance

摘要

The aim of our study was to evaluate fracture resistance of the PMMA complete dentures and to make a comparison between the classic acrylic maxillary complete dentures and the metal-reinforced ones, in terms of fracture resistance during function and to compare the fracture pattern of the two groups of complete dentures. We used maxillary complete dentures made of heat-processed acrylate, 5 exclusively and 5 in which a metal-cast net in the form of a mesh was inserted after being casted, worn by patients for a period of 5 years. A bilateral progressive force was applied to the PM2-M1 area until the samples failed, recording the force value at which the first change occurred. A Universal Loading Machine was used. The results were analyzed using the ANOVA method. For the classic acrylic complete dentures group, the minimum fracture force value was 1060 N, the maximum fracture force value being 2443 N. For the reinforced complete dentures group, the minimum fracture force value was 3320 N, the maximum value being 3760 N. Statistical analysis of data using the ANOVA shows that the results are statistically relevant, with a p value of 0.000137 (p<0,05). All the dentures from the classic acrylic complete dentures group fractured presenting two or more fracture lines, most of them involving also fractures on the acrylic teeth and breaking into multiple pieces, while all the dentures from the reinforced complete dentures group fractured presenting one or two fracture lines, most of them without detachable fragments and involving also fractures on the acrylic teeth.