This in vitro study investigated the extrinsic tooth-whitening effect of bleaching products containing polyphosphates on the dental enamel surface compared to 10% carbamide peroxide (CP). Eighty human molars were randomly allocated into four whitening-products groups. Group A (control) was treated with 10% CP (Opalescence). The other groups with non-CP over-the-counter (OTC) products were group B = polyphosphates (iWhiteWhitening-Kit); group C = polyphosphates+fluoride (iWhite-toothpaste); and group D = sodium bicarbonate (24K-Whitening-Pen). L*, a*, b* color-parameters were spectrophotometer-recorded at baseline (T0), one day (T1), and one month (T2) post-treatment. Changes in teeth color (ΔE_ab) were calculated. Data were analyzed using ANOVA and the Bonferroni test (α = 0.05). Groups A, B, and D showed significant differences in ΔL*&Δa* parameters at T1, but not in Δb* at T0. Group C showed no difference for ΔL*, Δa*, Δb* at T0 and T1. Group A showed differences for ΔL*, Δa*, Δb*, at T2, while groups B, C, and D had no difference in any parameters at T0. At T1, ΔE_ab values = A > D> B > C (ΔE_ab = 13.4 > 2.4 > 2.1 > 1.2). At T2, ΔE_ab values increased = A > B > C > D (ΔE_ab = 12.2 > 10.6 > 9.2 > 2.4). In conclusion, the 10% CP and Biomimetic polyphosphate extrinsic whitening kit demonstrated the highest color change, while simulated brushing with dark stain toothpaste and a whitening pen demonstrated the lowest color change at both measurement intervals.

Background/Objectives: Despite clear benefits, conventional rubber dam use remains low due to barriers that often originate during undergraduate training. To examine a potential approach to mitigating these barriers, this study evaluated the efficacy and feasibility of OptraDam^® Plus, a user-friendly alternative to the conventional rubber dam, in preclinical simulation training. Methods: In this 2 × 2 crossover trial, preclinical undergraduate students were randomly assigned to two groups to perform two types of dental isolation, conventional rubber dam and OptraDam^® Plus, in alternating sequences on a dental simulator. The efficacy and feasibility of both systems were evaluated based on application time, isolation quality, and students’ perceptions. Results: Data from 94 randomized students were collected and analyzed. Although students’ performance was suboptimal with both systems, there were significant differences in efficacy and feasibility between them. Application time was shorter with the conventional rubber dam (mean reduction 77 s; 95% CI 4–151; p = 0.039), whereas using OptraDam^® Plus was associated with 51% lower odds of achieving a higher isolation quality category (OR 0.49; p = 0.011). In addition, students perceived the conventional rubber dam to be superior to the OptraDam^® Plus in achieving higher-quality dental isolation and in their confidence in using it. Conclusions: OptraDam^® Plus cannot be considered a suitable alternative to the conventional rubber dam in preclinical simulation training due to its inferior efficacy and feasibility. The findings of this study challenge the assumption that utilization of newer marketed “user-friendly” rubber dam systems necessarily overcome the core technical barriers faced by undergraduate students.