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ObjectiveTo evaluate and compare color stability and gloss retention of ceramic stains and glaze under simulated toothbrushing using dentifrices with different relative dentin abrasion (RDA).Materials and MethodsFeldspathic porcelain, lithium disilicate, 3 mol% yttria partially stabilized zirconia, and 5 mol% yttria partially stabilized zirconia were evaluated. Ceramics were externally stained, glazed and mounted in the toothbrush simulator. A toothbrush with 300 g force was applied. Regular toothpaste (72 RDA) and charcoal toothpaste (RDA <200) were used. Linear brushing motion with cycle intervals: 5 k, 10 k, 30 k, and 50 k was achieved. Change in color (CIEΔE2000) and gloss measurements were collected using a reflection spectrophotometer (Ci 7600, X‐rite) at baseline and cycle intervals. Repeated measures analysis of variance within specimen factors (ceramic type, toothpaste and cycles) was performed.ResultsΔE00 was significantly different at 50 k cycles and with zirconia ceramics (P < .0001). Charcoal toothpaste was significantly different in ΔE00 compared to regular toothpaste (P > .0001). Loss of gloss was observed at 5 k and 30 k (charcoal and regular toothpaste respectively) regardless type of ceramic (P > .0001).ConclusionGlass‐phase ceramics retain stains longer than zirconia ceramics. Charcoal toothpaste affect color and gloss stability. Ceramic glaze maybe lost within the first 6 months in patients' mouth.Clinical SignificanceLong‐term color and gloss stability of externally stained and glazed ceramics maybe a clinical concern. Charcoal toothpastes enhance loss of color and gloss of ceramic restorations.

Purpose The purpose of this retrospective, cross‐sectional study is to evaluate if there is a difference in number of visits (including fabrication and postoperative) and remake rate when comparing conventionally fabricated and digitally fabricated complete dentures by dental students in a predoctoral student dental clinic. Materials and methods This two‐year retrospective cross‐sectional study consisted of a chart review for patients receiving maxillary and/or mandibular complete dentures between 2017 and 2019 (n = 314) at the UNC Adams School of Dentistry predoctoral student clinic. No control group was determined for this study. Data were extracted for 242 conventional dentures and 39 digital dentures. Objective treatment outcomes were obtained for each included denture: the number of patient appointments from preliminary impressions to denture placement, the number of postoperative visits, any complications noted, and any need for remakes. Fisher's Exact Test and Cochran‐Mantel‐Haenszel analysis were completed with statistical significance set at p < 0.05. Results For the number of visits from preliminary impression to placement, 50% of conventionally fabricated dentures had 6 or more visits, while only 5% of digitally fabricated dentures had 6 or more visits. This difference for the number of patient visits was statistically significant (p < 0.05). Additionally, conventionally fabricated dentures required an average of 2‐3 postoperative visits, whereas digitally fabricated dentures required 1‐2 postoperative visits. This difference was also statistically significant (p < 0.05). For the number of dentures requiring remake, there was no statistical difference (p = 0.1904). Conclusions When comparing conventionally fabricated and digitally fabricated dentures in the predoctoral clinic, the digitally fabricated dentures required fewer patient appointments from start to finish, and fewer postoperative appointments than conventionally fabricated dentures. Fewer visits may be an important consideration for patients, especially those with limited access to care.

Objective Conventional complete denture protocols require several patient appointments with multiple laboratory procedures. There are multiple workflows incorporating digital technology that can expedite the process, whereas increasing predictability. The proposed digitally replicated denture technique (DRDT) demonstrates a predictable workflow for fabricating complete dentures for patients with existing dentures. Clinical Procedure A patient's existing maxillary and mandibular complete dentures were scanned with an intraoral scanner. The generated STL was then printed using a desktop 3D printer. This served as a custom tray and record base to decrease patient chair time and associated laboratory procedures. Conclusion The DRDT workflow incorporates digital technology into a complete denture protocol to minimize laboratory steps and chair time when fabricating complete dentures for patients with existing prostheses. Clinical Significance The use of a digitally replicated denture using rapid prototyping can streamline the process of complete denture fabrication for patients with existing dentures.

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