Universidade Veiga de Almeida

Visual shade selection in dentistry may be influenced by factors that include the background color and the illuminant.

The purpose of this clinical study was to evaluate the influence of using a gray background and a light-correcting device on visual shade selection.

Two experienced clinicians assessed the incisor color of 30 volunteers using the VITA 3D-MASTER shade guide. Visual analyses were carried out using or not (control) a gray background, with and without (control) a light-correcting device (Smile Lite). Furthermore, the use of a polarizing filter was evaluated. Data from a clinical spectrophotometer were defined as the standard instrumental analysis. The agreement and the similarity (based on the whitening indexes of tabs) were evaluated between instrumental and visual analyses. Statistical testing was conducted through ordinal logistic regression and repeated-measures ANOVA. The Shapiro-Wilk test was used to confirm the data distribution, and homogeneity of variance was assessed with the Levene test (α=.05) RESULTS: The use of Smile Lite resulted in lighter tabs than indicated by the instrumental analysis, and the opposite was observed in its absence. The polarizing filter did not affect the results (P>.05). For similarity, the illuminant improved the results (P<.001). The gray background reduced the differences between visual and instrumental analysis only in the absence of the Smile Lite (P<.001).

The color similarity between visual and instrumental analysis improved with the use of a light-correcting device with or without a polarization filter. A gray background was useful only without the light-correcting device.

To investigate whether the use of sports mouthguards (SMG) influences salivary parameters and oral health indices.

Electronic searches were conducted across six major databases and two sources of gray literature in July 2024, with no restrictions on language or publication date. Interventional studies assessing oral parameters in participants with and without SMG were included. Risk of bias (ROB) was evaluated using the NIH-NHLBI Quality Assessment Tools for before-and-after studies. Descriptive synthesis was performed, and the certainty of evidence was assessed with the GRADE approach.

Four studies met the inclusion criteria, encompassing a total of 202 male and female athletes aged 8 to 24 years. ROB ratings were classified as fair in three studies (75%) and poor in one study (25%). Evaluated salivary parameters included pH, stimulated and unstimulated flow rates, microbial count, saliva consistency, and buffering capacity. Additionally, oral indices such as full mouth plaque and bleeding scores were assessed. The studies demonstrated high heterogeneity in collection and analysis methods, outcome evaluation, and follow-up duration. Overall, the influence of SMG use on salivary pH (n = 4; 100%) and stimulated flow rate (n = 2; 100%) was inconclusive. SMG use did not affect microbial count (n = 2; 100%) or saliva consistency (n = 1; 100%) but was associated with a decrease in buffering capacity (n = 1; 100%). An increase was noted in unstimulated flow rate (n = 1; 100%) and oral indices (n = 1; 100%) with SMG use. The certainty of the evidence was rated as very low for all evaluated parameters.

SMG use appears to impact saliva's buffering capacity but does not influence its consistency or microbial count. Despite the limited literature and methodological limitations of existing studies, this systematic review provides insights that could inform the design of more rigorous primary research, ultimately strengthening the evidence base on this topic.

The main goal of this study is to evaluate the potential risk of high levels of particulate matter with diameter ≤ 2.5 μm (PM_2.5) on children´s health, using PM_2.5 monitoring in the western zone of the city of Rio de Janeiro and health data determined in the same area. Results showed that, during this period, in more than 50% of days PM_2.5 concentration were > 15 µg m^- 3. This value is the maximum concentration to ensure a good air quality according to the WHO guidelines and the Brazilian legislation. Furthermore, in 2023, 28.24% and 5.29% of mortality rates, for children between 1 and 5 years old, were due to respiratory and cardiovascular diseases respectively. On the basis of the particulate matter levels recorded in this study and the WHO AIRQ + software, we estimate that PM_2.5 levels may have contributed to approximately 8.5% of the total number of these deaths and could have been prevented.