Objective: To evaluate the clinical wear of two different denture tooth materials in two groups of subjects.
Material and Methods: Twenty-eight subjects received full dentures with two different materials at three centers. In center A (n=18, median age 64 years, 13 w, 5 m), the denture tooth material was based solely on PMMA with organic fillers (SR Postaris DCL, Ivoclar Vivadent, Liechtenstein). In centers B and C (n=10, median age 67.5 years, 3 w, 7 m) the denture material contained anorganic nanofillers (NFC, Candulor, Switzerland). At baseline and after 12 months impressions of the posterior teeth were poured with improved stone. After laser scanning (etkon es 1, Germany) the casts were superimposed and matched (Match 3D, etkon). Maximal vertical loss (µm) was calculated for each tooth type and subject by averaging the vertical loss of the buccal and oral wear facets of each posterior tooth and taking the maximal value of those. The data were logarithmically transformed to normalize their distribution.
Results: For the pooled data the mean vertical loss of the group with the composite material NFC was statistically significantly lower after 12 months than that of the group with the DCL material (ANOVA, p=0.013): median values NFC 150µm, DCL 253µm. The first molars showed statistically significant more wear than the first premolars in the DCL group (Wilcoxon test, p=0.03) whereas in the NFC group no such difference has been observed. The mean coefficient of variation was 27% for the NFC group and 60% for the DCL group.
Conclusions: The composite based denture tooth material NFC showed a statistically significant lower wear that the PMMA based DCL material after 12 months of service. The variability within the subject groups was substantially lower for the NFC compared to the DCL material.