Improved fit of maxillary complete dentures processed on high expansion stone casts.

PURPOSE

Although relatively well-fitting dentures are produced at low cost and with easy-to-manipulate material, current denture base materials are not ideal. Because acrylic resin complete and removable partial dentures change dimensionally as a result of polymerization and thermal contractions, a high expansion stone was tested in this study to determine its ability to compensate for some of the dimensional change.

MATERIAL AND METHODS

Maxillary complete dentures were processed on type III dental stone and high expansion stone casts. The accuracy of fit along the posterior palatal border was measured and compared after the prostheses were trimmed and polished and after their immersion in water at 23 degrees C at 1-day and 1-week intervals.

RESULTS

Statistical analysis of the data revealed that at every measurement interval the maxillary complete dentures processed on high expansion stone had posterior palatal border openings that were significantly smaller when compared with type III dental stone (p < 0.001).