Abstract Background Genetic polymorphisms have been shown to influence several physiological traits, including dental and craniofacial characteristics. Understanding the clinical relevance of genetic polymorphisms in dental practice is crucial to personalize treatment plans and improve treatment outcomes. Objective to evaluate the association between dental age and genetic polymorphisms in genes encoding estrogen receptors alpha and beta (ESR1 and ESR2, respectively) in a sample of Brazilian children. Methodology This retrospective cross-sectional study was performed with children undergoing orthodontic treatment. Patients with syndromes, congenital anomalies, craniofacial deformities, under hormonal or systemic treatment, and with a previous history of facial trauma were excluded. Panoramic radiographs were used to assess dental age according to the Demirjian, Goldstein, and Tanner method. A delta [dental age-chronological age (DA-CA)] was obtained, which shows whether the patient tends to have a normal, delayed (negative values), or advanced (positive values) dental age. DNA isolated from buccal cells was used to genotype four genetic polymorphisms: rs9340799 (A>G) and rs2234693 (C>T), located in ESR1; and rs1256049 (C>T) and rs4986938 (C>T), located in ESR2. A statistical analysis was performed and values of p<0.05 indicated statistical difference. Results A total of 79 patients were included, 44 (55.70%) girls and 35 (44.30%) boys. The Demirjian, Goldstein, and Tanner method, in general, overestimated patients’ age by 0.75 years. There was no difference in the delta of dental age between the sexes (p>0.05). Genetic polymorphisms in ESR1 and ESR2 were not associated with dental age (p>0.05). Conclusion The studied genetic polymorphisms in ESR1 and ESR2 were not associated with dental age in Brazilian children.

Abstract This study evaluated how Er,Cr:YSGG laser, associated or not with 5% fluoride varnish, influences the surface roughness and volume loss of bovine root dentin submitted to erosive and/or abrasive wear. One hundred and twenty dentin specimens were divided into the groups: without preventive treatment (WPT), 5% fluoride varnish (FV); Er,Cr:YSGG laser irradiation (L), and varnish combined with laser (FV + L). The specimens (n = 10) were subdivided into: 1 = erosion (E); 2 = abrasion (A); and 3 = erosion followed by abrasion (E + A). The erosive solution used was a soft-drink (pH = 2.42 at 4ºC) applied in 5-min cycles twice a day for 10d. Abrasive wear involved brushing for 60s with an electric brush (1,600-oscillations/s) at a load of 2.0N. Surface roughness and volume loss were evaluated using a laser scanning confocal microscope. Roughness data were submitted to one-way ANOVA and Tukey post-hoc test. For volume loss, the Kruskal-Wallis and Dunn’s post-hoc tests were used (α = 5%). The lowest values of roughness were found in the control areas of all subgroups (p > 0.05). In the experimental area, the [(WPT) + (E+A)] subgroup had a significantly higher roughness (5.712 ± 0.163 μm 2 ) than the other subgroups (p < 0.05). The L and (FV + L) groups had statistically similar roughness, regardless of the type of wear. The (FV + L) group had the lowest volume loss, regardless of the type of wear performed: [(FV + L) + (E)] = 7.5%, [(FV + L) + (A) = 7.3%, and [(FV + L) + (E + A)] = 8.1%. The subgroup [(WPT) + (E + A)] had the highest volume loss (52.3%). The proposed treatments were effective in controlling dentin roughness. Laser irradiation can be an effective method to increase root dentin resistance after challenges and limit problems related to non-carious lesions.

Este estudo avaliou a influência de um refrigerante a base de cola e um suco de laranja a base de soja na erosão da superfície e subsuperfície do esmalte do dente decíduo, em função do tempo de exposição. Setenta e cinco incisivos decíduos foram divididos para o teste de microdureza (n=45) ou para a análise em microscópio eletrônico de varredura (MEV) (n=30). Os espécimes foram alocados aleatoriamente em 3 grupos: I - saliva artificial (controle); II - refrigerante a base de cola; e III - suco de laranja a base de soja. Ciclos de imersão nas bebidas foram realizados sob agitação durante 5 min, 3 vezes ao dia, durante 60 dias. A microdureza superficial foi mensurada aos 7, 15, 30, 45 e 60 dias. Após 60 dias, os espécimes foram seccionados e a microdureza subsuperficial foi mensurada aos 30, 60, 90, 120, 150 e 200 μm. Os dados foram analisados pelos testes ANOVA e Tukey (α=5%). Os grupos II e III apresentam uma diminuição similar da microdureza superficial. O grupo II apresentou menores valores de microdureza subsuperficial. As imagens de MEV revelaram que após 60 dias as superficies mostraram perdas de estruturas claramentes identificadas, diferentemente das superfícies imersas em saliva artificial. Pode-se concluir que a erosão das superficies expostas ao refrigerante a base de cola foi mais acentuada e diretamente proporcional ao tempo de exposição à bebida.

This study evaluated the influence of a cola-type soft drink and a soy-based orange juice on the surface and subsurface erosion of primary enamel, as a function of the exposure time. Seventy-five primary incisors were divided for microhardness test (n=45) or scanning electron microscopy (SEM) analysis (n=30). The specimens were randomly assigned to 3 groups: 1 - artificial saliva (control); 2 - cola-type soft drink; and 3 - soy-based orange juice. Immersion cycles in the beverages were undertaken under agitation for 5 min, 3 times a day, during 60 days. Surface microhardness was measured at 7, 15, 30, 45 and 60 days. After 60 days, specimens were bisected and subsurface microhardness was measured at 30, 60, 90, 120, 150 and 200 µm from the surface exposed. Data were analyzed by ANOVA and Tukey’s test (a=0.05). Groups 2 and 3 presented similar decrease of surface microhardness. Regarding subsurface microhardness, group 2 presented the lowest values. SEM images revealed that after 60 days the surfaces clearly exhibited structural loss, unlike those immersed in artificial saliva. It may be concluded that erosion of the surfaces exposed to the cola-type soft drink was more accentuated and directly proportional to the exposure time.

Este estudo avaliou in vitro a resistência ao cisalhamento (RC) de um selante resinoso [Fluroshield (F), Dentsply/Caulk] em associação com um sistema adesivo de condicionamento total [Adper Single Bond 2 (SB), 3M/ESPE] ou auto-condicionante [Clearfil S3 Bond (S3), Kuraray Co., Ltd.] após contaminação salivar do esmalte, comparando dois protocolos: fotopolimerização individual do sistema adesivo e do selante ou simultânea de ambos os materiais. Superfícies mesiais e distais de esmalte de 45 terceiros molares hígidos foram aleatoriamente alocadas em 6 grupos (n=15), de acordo com a técnica adesiva empregada: I - F foi aplicado sobre o esmalte condicionado com ácido fosfórico a 37%. Os demais grupos foram contaminados com saliva (0,01 mL por 10 s) após o condicionamento ácido. II - SB e F foram fotopolimerizados separadamente; III - SB e F foram fotopolimerizados simultaneamente; IV - S3 e F foram fotopolimerizados separadamente; V - S3 e F foram fotopolimerizados simultaneamente; VI - F foi aplicado sobre o esmalte condicionado e contaminado sem sistema adesivo. RC foi testada em uma máquina universal de ensaios (0,5 mm/min; 50 kgf) e os dados analisados por ANOVA a 1 fator e teste exato de Fisher (α=0,05). As interfaces adesivas foram analisadas quanto ao padrão de fraturas em estereomicroscópio. Três espécimes de cada grupo foram analisados qualitativamente em microscópio eletrônico de varredura. As médias de RC em MPa foram: I-12,28 (±4,29); II-8,57 (±3,19); III-7,97 (±2,16); IV-12,56 (±3,11); V-11,45 (±3,77); e VI-7,47 (±1,99). Conclui-se que a fotopolimerização individual ou simultânea do sistema adesivo e do selante não afetou os valores de RC ao esmalte contaminado. S3/F apresentou RC estatisticamente maior do que os grupos tratados com o sistema adesivo etch-and-rinse SB e estatisticamente semelhante ao grupo controle, no qual o selante foi aplicado em condições ideais, na ausência de contaminação salivar.

This study evaluated in vitro the shear bond strength (SBS) of a resin-based pit-and-fissure sealant [Fluroshield (F), Dentsply/Caulk] associated with either an etch-and-rinse [Adper Single Bond 2 (SB), 3M/ESPE] or a self-etching adhesive system [Clearfil S3 Bond (S3), Kuraray Co., Ltd.] to saliva-contaminated enamel, comparing two curing protocols: individual light curing of the adhesive system and the sealant or simultaneous curing of both materials. Mesial and distal enamel surfaces from 45 sound third molars were randomly assigned to 6 groups (n=15), according to the bonding technique: I - F was applied to 37% phosphoric acid etched enamel. The other groups were contaminated with fresh human saliva (0.01 mL; 10 s) after acid etching: II - SB and F were light cured separately; III - SB and F were light cured together; IV - S3 and F were light cured separately; V - S3 and F were light cured simultaneously; VI - F was applied to saliva-contaminated, acid-etched enamel without an intermediate bonding agent layer. SBS was tested to failure in a universal testing machine at 0.5 mm/min. Data were analyzed by one-way ANOVA and Fisher's test (α=0.05).The debonded specimens were examined with a stereomicroscope to assess the failure modes. Three representative specimens from each group were observed under scanning electron microscopy for a qualitative analysis. Mean SBS in MPa were: I-12.28 (±4.29); II-8.57 (±3.19); III-7.97 (±2.16); IV-12.56 (±3.11); V-11.45 (±3.77); and VI-7.47 (±1.99). In conclusion, individual or simultaneous curing of the intermediate bonding agent layer and the resin sealant did not seem to affect bond strength to saliva-contaminated enamel. S3/F presented significantly higher SBS than the that of the groups treated with SB etch-and-rinse adhesive system and similar SBS to that of the control group, in which the sealant was applied under ideal dry, noncontaminated conditions.