Periodic evaluation of the occlusal vertical dimension of maxillary dentures from the wax trial denture through 48 hours after polymerization

Abstract

Purpose: This study measured the effects of commercial resin type on maxillary complete dentures with monoplane teeth by periodically comparing the occlusal vertical dimension of the polymerized dentures with the baseline, wax trial denture fiducial measurements.Materials and Methods: Commercially available compression-molded, injection-molded, and fluid poly(methyl methacrylate) resins, as well as one compression-molded methyl acrylate ester copolymer, were evaluated. Ten dentures were fabricated from each resin using monoplane teeth. The occlusal vertical dimension at the articulator pin was measured at the wax denture stage for each specimen, and changes in occlusal vertical dimension for each denture were evaluated at a simulated laboratory remount, and at 0, 3, 6, 24, and 48 hours after a simulated clinical remount. Repeated measures analysis of variance (␣ ‫؍‬ 0.05) and post hoc one-way factorial analysis of variance and Scheffe's F-Tests for each resin group were performed using ranks of raw data.Results: Changes in the maxillary denture mean occlusal vertical dimensions were recognized throughout the evaluation periods compared with the wax-denture baseline, and time was a significant influence on displacement (p ‫؍‬ .0001). Only the compression-molded poly(methyl methacrylate) dentures exhibited a mean laboratory remount occlusal vertical dimension that was significantly greater than the mean wax denture measurement, and all resin systems exhibited occlusal error that was significantly less than the laboratory remount measurements at 48 hours. At 48 hours, all resin groups exhibited mean occlusal vertical dimension changes that were less than 1 mm compared with the wax denture. Only compression-molded poly(methyl methacrylate) dentures exhibited a mean 48-hour clinical remount measurement that was statistically similar to the mean wax denture occlusal vertical dimension.Conclusions: Individual maxillary dentures from all resin types and at all intervals exhibited dimensional change. At the last evaluation period, the compression-molded poly(methyl methacrylate) showed no change in mean occlusal vertical dimension from baseline, whereas remaining groups exhibited occlusal vertical dimensions significantly less than baseline.

Influence of the Fast-processing Technique on the Number of the Occlusal Contacts and Occlusal Vertical Dimension of Complete Dentures

“…2,4,6-9 some have merely concerned a single jaw, 4,6 while others have considered both jaws. 2,[7][8][9]14,15 The present study has included completely edentulous patients master casts on which teeth were setup.…”

“…Keenan et al 4 compared the occlusal and vertical height stability of complete removable dentures prepared by different combinations of injection/compression molding and microwave/hot air oven heating and found no significant differences between the groups after 28 days. Swards et al 6 reported that the OVDs of dentures prepared with compression molding and heat polymerization were significantly changed after processing. All groups showed significant differences in the vertical height after 48 hours, but the changes were smaller than with the remounting process.…”

“…The vertical height is increased less with the injection molding technique than with compression molding. 3,4,6,7,9 Compression molding is the most common molding method and was used in the present study. The decrease in the number of the occlusal contacts and the increase in the vertical dimension of occlusion may be related to the heating duration and intensity, to compression during molding or to the lack of uniform thickness in the flanges.…”

“…[1][2][3][4][5] The stability of a complete denture is highly dependent on an even distribution of the occlusal load, which can be achieved by obtaining the maximum intercuspation in the centric relation and by elimination of occlusal errors. [6][7][8][9] This intercuspation should be established bilaterally on the posterior artificial teeth. Unilateral and insufficient occlusal contacts, which are defined as an incorrect occlusion, and the consequent trauma affect the retention and resistance; cause soft tissue soreness, accelerate residual ridge resorption; and decrease masticatory efficiency.…”

“…20,21 Several studies have discussed the effect of molding and processing methods on the OVD of the complete dentures. [2][3][4][5][6][7][8] However, the effect of the applied method on the number and distribution of the occlusal contacts has not been investigated in great detail. 3 Moreover, these studies have mostly been done on low numbers of simulated edentulous jaws or models.…”