Brazilian Oral Research最新文献

This study evaluated the background and effect of surrounding colors on the color blending of a single-shade composite used in a thin layer. Disc-shaped specimens (1.0 mm thickness) were built with the Vittra APS Unique composite surrounded (dual specimens) or not surrounded (simple specimens) by a control composite (shade A1, A2, or A3). Simple specimens were also built with only control composites. The specimen color was measured against white and black backgrounds with a spectrophotometer (CIELAB system). The whiteness index for dentistry (WID) was calculated for simple specimens. Differences (ΔE00) in color and translucency parameters (ΔTP00) between the simple/dual specimens and the controls were calculated. The translucency adjustment potential (TAP) and color adjustment potential (CAP) were estimated based on the ratios between data from simple and dual specimens. The Vittra APS Unique composite showed higher WID values than the controls. No differences between ΔTP00_SIMPLE and ΔTP00_DUAL were observed for any of the shades. The composite shade did not affect TAP values. The lowest values of ΔE00_SIMPLE and ΔE00_DUAL were observed for shade A1 regardless of the background color. For the white background, ΔE00_SIMPLE values did not differ from those of ΔE00_DUAL for all shades. Only A1 showed ΔE00_DUAL values lower than ΔE00_SIMPLE when the black background was used. The highest modulus of CAP (negative values for the white background) was observed when shade A1 surrounded the Vittra APS Unique composite. The color blending ability of the single-shade resin composite used in a thin layer was affected by both the surrounding shade and background color.

Pain is common in orthodontic treatment, is subject to individual variation, and is associated with anxiety and stress, which can potentially become catastrophizing. The aim of the present study was to determine the variability of pain response after the insertion of orthodontic separators and to assess the association of pain levels with dental anxiety, catastrophizing, tooth sensitivity, and genetic expression of cytokines. To this end, 70 patients of both genders were divided into two equal groups according to the elastomeric separator used: G1 (Dentaurum) and G2 (Orthometric). Two separators were inserted in the mesial and distal sides of the lower right first molar. Participants were instructed to rate the level of pain at T0 (before insertion), T1 (just after insertion), and T2 (24 hours after insertion) on a visual analog scale. The gingival crevicular fluid was collected at T0 and T2. The levels of anxiety, catastrophizing, tooth sensitivity, and cytokine expression were also assessed. Statistical analysis was performed with the Fisher-Freeman-Halton, chi-squared, Spearman's correlation, and dependent and independent t tests (α=5%). Pain intensity was higher at T2 than at T1, in both groups (P<.05). An association was established (P<.05) between pain intensity at T1 and catastrophizing, and at T2 with anxiety and catastrophizing. Within-group differences in cytokine expression were found between T0 and T2. There was no correlation between cytokine expression and pain levels, anxiety, catastrophizing, and sensitivity at T2. Tooth separation produced variable pain levels, which were influenced by anxiety and catastrophizing, however, pain level was not correlated with increased cytokine expression.

Burning mouth syndrome (BMS) is a condition characterized by painful symptoms of the oral mucosa, despite the absence of any clinical signs. Its etiology is unknown, and there is still no effective treatment to date. Current evidence has shown neuropathic impairment in BMS patients. Neuropathic pain can be related to the dysfunction of voltage-gated sodium channels, considering that these receptors regulate the induction of action potentials in nociceptive neurons. This study evaluated the gene expression of voltage-gated sodium channels Na v 1.7, Na v 1.8 and Na v 1.9 in these patients. The gene expressions of these channels were assessed by real time RT-PCR analysis of fresh-frozen tongue biopsies in a case-control study composed of 12 patients with BMS, and 5 healthy control patients, proportionally matched by sex and age, and analyzed using the 2^(-Delta Delta CT) method. There was no statistically significant difference between the analyzed groups, despite the increase in Na v 1.7 (fold-change = 3.13, p = 0.52) and decrease in Na v 1.9 (fold-change = 0.45, p = 0.36) gene expression in the BMS group. The Na v 1.8 gene was not expressed in any of the samples analyzed. Although the gene expression in the voltage-gated sodium channels in BMS under study seems to be comparable with that of the normal oral mucosa, the functionality of these channels in BMS has not yet been identified, thus suggesting that further research is needed to better understand these voltage-gated sodium channels.

The genetic basis of oral epithelial (OED) is unknown, and there is no reliable method for evaluating the risk of malignant transformation. Somatic mutations are responsible for the transformation of dysplastic mucosa to invasive cancer. In addition, these genomic variations could represent objective markers of the potential for malignant transformation. We performed whole-exome sequencing of 10 OED samples from Brazilian and Chilean patients. Using public genetic repositories, we identified 41 deleterious variants that could produce high-impact changes in the amino acid structures of 38 genes. In addition, the variants were filtered according to normal skin and Native American genome profiles. Finally, 13 genes harboring 15 variants were found to be exclusively related to OED. High-grade epithelial dysplasia samples showed a tendency to accumulate highly deleterious variants. We observed that 62% of 13 OED genes identified in our study were also found in head and neck squamous cell carcinoma. Among the shared genes, eight were not identified in oral squamous cell carcinoma. To our knowledge, we have described for the first time 13 genes that are found in OED in a Latin American population, of which five genes have already been observed in oral squamous cell carcinoma. Through this study, we identified genes that may be related to basal biological functions in OED.

The aim of this study was to develop and validate a questionnaire that allows a systematic evaluation of the impact of self-perceived oral health on expectations of getting a job on adult population seeking dental care, and to describe its associations with demographic characteristics, job related, and health coverage variables. We designed a descriptive cross-sectional study including men and women aged 18 to 65 years from a population seeking dental services in a walk-in clinic. In a first stage we design and validated an instrument on a sample of 100 subjects. The questionnaire was registered in a Likert scale, with higher scores represented higher impact of the oral status self-perception on employability. We calculated internal consistency, construct validity, and domains validation. The final instrument consisted in an 18-item questionnaire (Cronbach α = 0.814), grouped into two domains based on exploratory and confirmatory factor analysis. The total variance explained with values >1 was 66 percent, grouping questions into six components. One domain refers to oral health status and importance of dental aesthetics, while the other refers to specific job-seeking elements. In a second stage we applied the questionnaire on 800 participants from the same population of reference. Women, people who intended to change jobs, those younger than 40 years old, having health insurance, and higher educational level showed statistically significant higher scores than their counterparts (p<0.001). We developed a tool that enables evaluating the impact of self-perceived oral health on expectations of getting a job for adults seeking emergency care in a dental clinic.

The pandemic caused by coronavirus has resonated throughout different levels of health care in Brazil and, in this context, the present research aimed to evaluate this impact on tertiary dental care provided by the Unified Health System (SUS). Therefore, an ecological study was conducted with data obtained from the Hospital Information System processed by the Portal of the Department of Informatics of SUS. The sample consisted of patients of all sexes and age groups, whose Hospital Admission Authorizations (AIHs) were approved for dental tertiary care procedures from January 2015 to December 2020. Descriptive analyses and the ANOVA test with a significance level set at p < 0.05 were used. When the annual mean numbers of AIHs approved were evaluated, findings showed that on an average, the Southeast region authorized a higher number of procedures (p-value < 0.001), however, in the pandemic year (2020), a reduction of approximately 24.5% of these hospitalizations occurred throughout Brazil, with the Midwest being the region most affected (32.12%). A percentage increase occurred in the Surgical Treatment of Oral sinus/Oral nasal Fistula (16.1%), in addition to a significant decrease in performing procedures for Resection of Mouth Lesion (33.4%). In the pandemic year, there was a reduction of 14% in expenditures related to hospital services and 23.26% related to professional services. It was concluded that the data presented demonstrated a significant reduction in AIHs for tertiary dental care in the pandemic year.

This study tested a novel in vitro dental erosion-abrasion model and the performance of cross-polarization optical coherence tomography (CP-OCT) in longitudinally monitoring the simulated lesions. Thirty human enamel specimens were prepared and randomized to receive three dental erosion-abrasion (EA) protocols: severe (s-EA, lemon juice/pH:2.5/4.25%w/v citric acid), moderate (m-EA, grapefruit juice/pH:3.5/1.03%w/v citric acid) and no-EA (water, control). EA challenge was performed by exposing the specimens to acidic solutions 4x/day and to brushing 2x/day with 1:3 fluoridated toothpaste slurry, for 14 days. Enamel thickness measurements were obtained using CP-OCT at baseline (D0), 7 (D7) and 14 days (D14) and micro-computed tomography (micro-CT) at D14. Enamel surface loss was measured with both CP-OCT and optical profilometry at D0, D7 and D14. Data was analyzed with repeated-measures ANOVA and Pearson's correlation (r) (α = 0.05). CP-OCT enamel thickness decreased over time in the s-EA group (D0 >D7 > D14, p < 0.001) and m-EA group (D0 > D14, p = 0.019) but did not change in the no-EA group (p = 0.30). Overall, CP-OCT and micro-CT results at D14 correlated moderately (r = 0.73). CP-OCT surface loss was highest for s-EA (p <0.001) but did not differ between moderate and no-EA (p = 0.25). Enamel surface loss with profilometry increased with severity (no-EA>m-EA>s-EA, p < 0.001). D14 surface loss was higher than D7 for both methods except for the no-EA group with profilometry. CP-OCT and profilometry had moderate overall correlation (r = 0.70). Our results revealed that the currently proposed in vitro dental erosion-abrasion model is valid and could simulate lesions of different severities over time. CP-OCT was a suitable method for monitoring the EA lesions.

The present study evaluated the effect of the taper angle of different internal conical connection implants and cyclic loading on the implant-abutment bacterial seal. A total of 96 implant-abutment sets were divided into eight groups. Four groups of different taper degrees with cyclic mechanical loading of 500,000 cycles per sample, with a 120-N load at 2 Hz before analysis [16DC (16-degree, cycled), 11.5DC (11.5-degree, cycled), 3DC (3- degree, cycled) and 4DC (4- degree, cycled)] were compared to four control groups without cyclic loading [16D (16-degree), 11.5D (11.5-degree), 3D (3-degree), and 4D (4-degree)]. Microbiological analysis was performed by immersing all samples in a suspension containing Escherichia coli and incubating them at 37°C. After 14 days, the presence of bacterial seals was evaluated. Fisher-Freeman-Halton exact tests and binomial tests were performed (5% significance level). The groups showed significant differences in bacterial seal, and mechanical load cycling improved the bacterial seal in the 3DC group. In all other groups, no significant differences in bacterial seal were found between cycled and uncycled samples. To conclude, the internal conical connection with a 3-degree taper angle showed better results than the other connection with different angles when subjected to load cycling. However, none of the angles tested were fully effective in sealing the implant-abutment interface.