Method for enhancing retention in complete denture bases

Physical retention of a denture depends on adhesion of a salivary film to its fitting surface and supporting tissues. Adhesion is influenced by many factors.

This study examined the effect of the texture of the fitting surface on denture retention.

According to the method developed, mucosal-supported palatal bases were made for 10 dentate subjects who had no obvious oral disease, history of allergy to dental materials, or palatal mucosal undercuts. A specially designed strain gauge force transducer and a pen-chart recorder were used to record forces that were needed to dislodge the bases from the palate. Forces were recorded 30 times (10/day) for each subject. Similar forces were recorded after the fitting surface of each base was uniformly air-particle abraded under 4 kg/cm2 of pressure for 1 minute with 50-microm grit alumina dust. Data were analyzed with a 2-sample Student t test and a paired t test.

Substantial variations for all measurements were observed both between and within subjects. Notwithstanding, these variations, the mean retention of the bases significantly (P <.05) increased by more than 2-fold when the fitting surface was air-particle abraded. These force values were similar to those recorded previously for well-fitting mucosal-supported palatal bases in a separate group of dentate subjects.

While reinforcing the importance of good adaptation of the denture to the tissues, these findings also suggest that an additional improvement in denture retention can be accomplished after the fitting surface is air-particle abraded.