Mariana Evangelista Santos

Objective: To evaluate hydrogen peroxide (HP) permeability into the pulp chamber, objective color change, and enamel surface morphology after overnight use of over‐the‐counter (OTC) whitening pens. Materials and Methods: Fifty sound premolars were assigned to five groups ( n = 10): control, Optic White Pen LED (OW), Colgate Luminous White Whitening Pen (LW), Equate Teeth Whitening Kit (EQ), and Whiteness Perfect 10% (WP). Fifteen molars were used for enamel surface analyses (microhardness and roughness). Products were applied for 8 h/day for 10 days. HP penetration (μg/mL) and color change (Δ E _ab , Δ E ₀₀ , and WI _D ) were measured by spectrophotometer. Initial HP concentration and pH were determined by titration and pH meter. Data were analyzed using ANOVA ( α = 0.05). Results: EQ showed the highest HP concentration and the lowest pH. HP penetration was significantly higher for EQ and lowest for WP ( p < 0.05). No significant differences in Δ E _ab and Δ E ₀₀ were observed among products, while WI _D increased over time in all groups. Enamel surface changes were similar, except for EQ, which showed reduced microhardness ( p < 0.05). Conclusions: Overnight OTC whitening pens showed comparable cumulative bleaching efficacy. However, EQ resulted in greater pulpal HP penetration and enamel softening. Clinical Significance: Prolonged overnight OTC whitening pen use may increase pulpal exposure and enamel softening risk, reinforcing cautious use and professional supervision.

Objective: This randomized clinical trial evaluated the one‐year color stability and patient satisfaction regarding dental esthetic improvement after 37.5% hydrogen peroxide (37.5HP) in‐office bleaching with a reduced application protocol. Materials and Methods: Forty participants with a shade mean C2 or darker were randomly allocated into two treatment groups ( n = 20): two (37.5HP2) or three (37.5HP3) 8‐min applications per clinical session. Three bleaching sessions were performed at one‐week intervals. Tooth color was measured using a spectrophotometer at baseline, 1 week (1 W), 6 months (6 M), and 1 year (1 Y) post‐bleaching. Esthetic self‐perception was assessed using a 6‐point visual analogue scale. Statistical analysis was performed using the Shapiro–Wilk, Student's t ‐test, Tukey, Mann–Whitney, and Friedman tests ( p < 0.05). Results: No significant differences were observed between 37.5HP2 and 37.5HP3 for Δ, Δ E ₀₀ , or ∆WI _D across the evaluation periods ( p > 0.05). Although both treatment protocols remained effective at 1Y post‐bleaching, a significant color rebound was observed from the 6 M assessment ( p < 0.05). Patient satisfaction with dental esthetics was comparable between groups ( p = 0.3). Conclusions: Two and three 37.5% HP applications provided similar bleaching stability after one year. Patients remained highly satisfied with their smile, regardless of the number of gel applications. Clinical Significance: Clinicians may consider using a neutral 37.5% HP in‐office bleaching gel with two 8‐min applications per session, as it provides the same one‐year bleaching longevity as the manufacturer's recommended protocol of three applications.

Objective: This clinical trial aimed to evaluate the influence of a purple repositioning silicone guide on color assessment before and after at‐home tooth bleaching. Materials and Methods: Forty‐five individuals received 10% carbamide peroxide at‐home tooth bleaching using custom trays on both arches, 3 h per day for 2 weeks. Upper canines were evaluated with a spectrophotometer in two different ways: with and without (control) a purple silicone guide. Tooth color was assessed using the CIELab (Δ E * _ab ), CIEDE2000 (Δ E ₀₀ ), and the whitening index for dentistry (Δ WI _D ) at baseline, 2 and 4 weeks after the beginning of treatment. Data were analyzed using paired t tests for dependent samples ( p < 0.05). Results: At all evaluation periods, the use of the purple silicone guide resulted in lower b * values and higher WI _D values ( p < 0.001) compared with the control group. At 2 and 4 weeks, the repositioning guide resulted in lighter teeth (higher values of Δ E * _ab , Δ E ₀₀ , and Δ WI _D ) than the group that did not use the guide ( p < 0.04). Conclusions: The use of a purple repositioning guide with a spectrophotometer influenced the color measurement of upper canines before and after at‐home tooth bleaching.

This study aimed to analyze the cost-effectiveness of whitening toothpastes and at-home bleaching for the treatment of tooth discoloration.

Introduction. Universal single-shade composite resins are characterized by a property that enables the creation of restorations that mimic tooth structure to the extent possible with fewer shades of color. Objectives. This study aimed to instrumentally and visually evaluate the color correspondence of two single-shade composite resins in extracted human teeth multishade composite resins. Methods. Upper central incisors and upper and/or lower molars with intact buccal surfaces were selected. The study consisted of a control group (n = 20): Z250 XT (3M ESPE) (G1) multishade composite resin in colors A1 to A4, and a test group (n = 20) divided further into two equal groups, consisting of single-shade composite resin Omnichroma (Tokuyama Dental) (G2) and single-shade composite resin Vittra APS Unique from (FGM) (G3). Instrumental evaluation was performed using a spectrophotometer, and visual evaluation was performed by three observers. Descriptive measurements related to the differences in color obtained through instrumental means were analyzed using mean and standard deviation, wherein the means were compared using ANOVA, applying the Bonferroni post hoc test. Results. A statistically significant difference was observed among the groups (G1, G2, and G3) (ANOVA: ). For the visual assessment, regardless of the assessment group, 77.49% of the teeth were within the acceptable color-match classification, with the single-shade resins showing better correspondence than the multishade resins. Conclusion. Single-shade composite resins showed different color-matching results when compared to multishade resins, both in spectrophotometry and visual evaluations. Clinical Significance. Single-shade composite resins simplify the shade-selection process and are promising materials for use in dental practice.

This in vitro study evaluated the effect of 35% hydrogen peroxide (35HP) gels with different desensitizing agents on color, microhardness and roughness of bleached enamel. Forty enamel-dentin specimens (6x6x2 mm2) were obtained from twenty human molars. After color measurement with a spectrophotometer, the specimens were randomized into four groups (n= 10): 35HPw- 35HP without desensitizing agent; 35HPCa- 35HP with calcium; 35HPK- 35HP with 0.5% potassium nitrate; 35HPTFa- 35HPw + topical application of 5% potassium nitrate and 2% sodium fluoride (TFa). Specimens were evaluated for color (∆Eab* and ∆E00), Vickers microhardness (VHN) and, superficial and volumetric roughness (Ra and Sa, µm) using a 3D non-contact profilometer before and 1-week after bleaching. Data were analyzed by ANOVA and Tukey tests (p< 0.05). Both treatment groups promoted a significant whitening effect and there was no difference between them for any color parameters evaluated. All groups reduced significantly the VHN, but the 35HPK showed a reduction significantly major than the other groups. 35HPCa and 35HP+TFa did not avoid the of Ra and Sa increasing. It can be concluded that 35HP bleaching gels with different desensitizing agents did not affect the whitening efficacy. However, all treatments decreased the microhardness, the addition of calcium into 35HP gel and the application of TFa before bleaching did not revert the enamel roughness under in vitro conditions.

Covid-19 is a respiratory disease caused by the SARS-CoV-2 virus. The high rate of contagion and the spread of the virus in the population make the early detection of the pathogen the means for the adequate targeting of infection control measures. WHO directs sample collection on upper respiratory specimens, including nasopharyngeal and oropharyngeal swab or wash in ambulatory patients, as well as lower respiratory specimens: sputum and/or endotracheal aspirate or bronchoalveolar lavage, in addition to citing blood and feces. Among the various sample collection methods, saliva has been investigated and reported as a potential source for diagnosis. Thus, we propose to evaluate the current scenario, based on recent publications on the perspective of detecting SARS-CoV-2 in saliva as a diagnostic method for Covid-19. The detection of SARS-CoV-2 through saliva seems to be very promising, although obstacles such as the technique and the location of the collection and the sample size of the research carried out so far may present a limitation for its use. The current scenario presents saliva as a reliable method for the detection of SARS-CoV-2, due to the ease of obtaining the samples, the possibility of self-collection, low cost because there is no need to use specific equipment, in addition to reducing the risk of transmission for health professionals.