Denture trueness and subjective retention analysis of digital monolithic dentures

The aim is to evaluate the trueness and displacement of tooth position as well as subjective retention of the monolithic complete denture (CD).

Twenty-two completely edentulous patients received (n = 22) conventional heat polymerized acrylic CDs. The conventional dentures were scanned with desktop scanner (Medit T710; MEDIT corp.), and the files were sent for milling of monolithic discs (Ivotion, Ivoclar vivadent AG). The files of the scanned monolithic dentures were superimposed with reference scans of conventional dentures to evaluate trueness by using analytic software (Geomagic control X 2020). The amount and direction of tooth displacement were measured by superimposing the scanned monolithic and conventional dentures to the scanned reference waxed trial dentures through points on denture teeth. Retention was subjectively evaluated. Data were analyzed.

For the maxillary and mandibular arches, there was a statistically significant difference in the intaglio and cameo surfaces between the conventional and monolithic CDs. As for the deviation of the teeth position, there was a statistically significant difference between the conventional and monolithic CDs in both maxillary and mandibular teeth. Regarding subjective retention, mandibular monolithic CDs differed significantly from conventional CDs.

A difference was observed between the conventional heat polymerized and monolithic CDs at intaglio, cameo surfaces, and tooth position displacement. More deviation was induced by the cameo surfaces than by the intaglio surfaces, and the shell geometry did not the conventional CD. Practitioner evaluations indicated that monolithic dentures demonstrated superior retention relative to conventional dentures.