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The excessive occlusal wear of complete-arch implant-supported prostheses made with metal and acrylic resin is a clinical complication that can require repeated maintenance in certain patients. A patient who presented with moderate occlusal wear of the prosthetic teeth and substantial fracture of the maxillary anterior acrylic resin base only 2 years after a previous replacement of the acrylic resin base and denture teeth is described. Because of the patient's history and existing wear, both the maxillary and mandibular prostheses were repaired by replacing the acrylic resin bases and resin denture teeth but with the addition of cast gold occlusal surfaces on the posterior prosthetic teeth. The provided treatment helped this patient, who was likely to need more frequent maintenance visits in the future because of his history of accelerated occlusal wear and increased occlusal force. [ABSTRACT FROM AUTHOR]

The effect of staining beverages on the color of dentures made with computer-aided design and computer-aided manufacturing (CAD-CAM) is unknown. The purpose of this in vitro study was to evaluate the stainability of acrylic resins used in CAD-CAM–fabricated complete dentures compared with conventional materials. Acrylic resin denture teeth from 3 different manufacturers (2 conventional and 1 milled) were obtained (N=45). Denture base acrylic resin specimens were made with 3 different techniques (compression molding, injection molding, and milling) (N=45). Conventional and/or milled acrylic resins were used to make specimens comprising both denture teeth and denture base acrylic resins (4 conventional, 2 milled denture bases with bonded teeth, and 1 all-milled) (N=105). All specimens were then immersed in coffee, red wine, or distilled water as control. The CIELab color differences between before and after immersion were determined by using a VITA Easyshade spectrophotometer. The tooth-denture base interface of the denture blocks was evaluated visually for the presence of stain. The CIELab data were analyzed by using ANOVA, and chi-square test was used for visual assessment (α=.05). Significant interactions were found between each acrylic resin material and each staining solution immersion when compared with distilled water immersion (P <.001). Denture teeth had similar color change after immersion in coffee (P =.149), while the most pronounced color change was observed with Portrait teeth upon immersion in wine (P <.001). Injection-molded denture base specimens exhibited less color change upon staining in wine than compression-molded or milled specimens (P <.001). Upon staining in coffee, milled specimens were not significantly different from injection- (P =.053) and compression-molded specimens (P =.180). The chi-square test showed a significant association between processing technique and stain accumulation at the tooth-denture base interface when evaluated visually (P <.001). Stain accumulation was greatest with compression-molded specimens (58%), followed by injection-molded (43%) and milled specimens with bonded teeth (8%). Monolithic teeth with milled denture base had no stain deposits at the tooth-denture base interface. The stainability of milled acrylic resins was no better than that of conventional materials. However, CAD-CAM milled denture blocks with teeth and base acrylic resins had greater resistance to stain accumulation at the tooth-denture base interface than those of conventional processing methods. [ABSTRACT FROM AUTHOR]