Evaluation of damage to removable dentures in two cities in Finland.

The number of damaged dentures and type of damage to removable dentures repaired in dental laboratories was investigated using a questionnaire sent to 24 dental laboratories in Finland. Eight variables were examined for each damaged denture. The results showed that the type of dentures most commonly needing repair was the complete upper denture (49%). The most frequent type of damage was breakdown of the acrylic base and loosening of an artificial tooth. The chi-square test established a statistical dependence (p < 0.005) between damaged dentures and their age. Damaged upper partial dentures most frequently had natural teeth or fixed prostheses as antagonist teeth. Damaged lower skeletal dentures and acrylic partial dentures had a complete denture as the antagonist (p < 0.05). Removable dentures made of acrylic resin material seemed to break despite strengtheners, such as clasp wire.