Objective To evaluate the effect of charcoal‐based dentifrices on the color change (CC) and surface wear (SW) of resin composites. Materials and Methods Five dentifrices, including three toothpastes: Colgate total‐12 (C12), Black is the new White (CPX), and Natural (NAT); and two powders: Carvvo (CVV) and Whitemax (WMX), were evaluated. Composite blocks (5x5x2mm‐ Z350 3 M/ESPE, shade A2) were subjected to 417 and 5004 brushing cycles. The CC (n = 7, CIEDE2000; ΔE00) was evaluated using a spectrophotometer. SW (n = 5) was assessed using profilometry. The dentifrice particles were characterized by scanning electron microscopy (SEM). Results In 417 brushing cycles, resin composite exhibited higher color change upon being exposed to NAT, CVV and WMC than to C12 (p ≤ 0.05). In 5004 brushing cycles, resin composite showed higher color change values when exposed to all dentifrices, except C12 (p ≤ 0.05). The powders promoted higher SW on resin composite than C12 in both evaluation times (p ≤ 0.05). In 417 cycles, WMX caused higher SW on composite than C12, CPX, and NAT (p ≤ 0.05). No significant different SW was found between powders and charcoal‐based toothpastes after 5004 brushing cycles (p > 0.05). SEM showed larger particles for powder than for toothpaste dentifrices. Conclusion Within the limitations of this study, both null hypotheses have been rejected. Resin composites exposed to charcoal‐based dentifrices exhibited significantly (p ≤ 0.05) higher color change and surface wear than conventional toothpastes. Clinical Significance Color change and surface wear shown by charcoal dentifrices may compromise the longevity of restorations.

This in vitro study aimed to evaluate the gaps length and depth of cure of dual-cure bulk-fill resin composites inserted in box-shaped preparations. Box-shaped preparations (4 mm deep) were made in fifteen human third-molars and divided into three groups according to the resin composites (n=5): Dual-cure bulk-fill BulkEZ (BEZ); Dual-cure bulk-fill HyperFIL (HF); and Tetric Evoceram Bulk-fill (TETRIC), as control. Gaps length (%) was evaluated in tooth-restoration interface with micro-computed tomography (µCT). The restorations were sectioned, and the degree of conversion (DC) and Knoop microhardness were evaluated at five depths (0.3, 1, 2, 3, and 4 mm). Microhardness data were statistically evaluated using absolute values (KHN) and relative values (microhardness percentages in relation to top). Gaps length (%) increased in the following order: BEZ=TETRIC<HF. The microhardness percentages in relation to top significantly decreased from 2 mm for TETRIC and 3 mm for HF. BEZ had constant microhardness and DC at all depths, while HF and TETRIC presented a significant decrease on DC at 4 mm. Dual-cure bulk-fill composites did not reduce gaps compared to light-cure bulk-fill, but they can improve depth of cure of bulk-filled restorations.

ResumoIntrodução: O sucesso de restaurações indiretas depende de uma adequada união entre o cimento e o substrato dental. Portanto, a seleção e o conhecimento das características dos agentes cimentantes são importantes para a retenção da restauração indireta. Objetivo: Avaliar a resistência de união de dois cimentos resinosos diferentes à cerâmica de dissilicato de lítio. Metodologia: Dois grupos experimentais foram confeccionados: cimento resinoso convencional (Grupo CRC) e cimento resinoso autoadesivo (Grupo CRA). Para isso, dez discos de cerâmica de dissilicato de lítio (10 mm) foram pré-fabricados e, sobre cada disco, foram confeccionados quatro postes de cimento (0,7×1,0 mm), obtendo-se um total de 20 amostras de cada tipo de cimento. Os discos tiveram o mesmo tratamento de superfície para os dois grupos, que é padrão para as cerâmicas ricas em sílica, de acordo com o protocolo estabelecido pelo fabricante. As amostras foram submetidas ao teste de microcisalhamento para avaliar a resistência de união entre o cimento e a cerâmica. Posteriormente, o modo de falha foi analisado em microscópio ótico. Resultado: Os dados obtidos foram submetidos a teste estatístico. Foi observado que o grupo CRC apresentou maiores valores de resistência de união (15,29 MPa) em relação ao grupo CRA (12,41 MPa). Na análise do modo de falha, nenhuma amostra obteve fratura do tipo adesiva. Em ambos os grupos, CRC (75%) e CRA (65%), obtiveram-se mais falhas do tipo mista, seguidas pela falha coesiva. Conclusão: Ambos os cimentos apresentaram adesão à cerâmica. O cimento resinoso convencional apresentou maior adesão a cerâmica à base de dissilicato de lítio que o cimento resinoso autoadesivo.Descritores: Cerâmicas; resistência ao cisalhamento; cimentação; cimentos de resina; prótese dentária. AbstractIntroduction: The success of indirect restorations depends on the union between cement and dental substrate. Therefore, the selection and knowledge of the characteristics of cement is important for the retention of indirect restoration. Objective: Is to evaluate the bond strength of two different resin cements to ceramic lithium disilicate. Methodology: Two experimental groups were made: conventional resin cement (CRC Group) and self-adhesive resin cement (CRA Group). With this, 10 lithium disilicate ceramics discs (10 mm) were prefabricated and on each disc were made 04 cement posts (0.7×1.0 mm), yielding a total of 20 samples of each type of cement. The disks had the same surface treatment for both groups, which is standard for the rich silica ceramic according to the protocol established by the manufacturer. The samples were submitted to microshear test to evaluate the bond strength between the cement and ceramics. Subsequently, the fail mode was analyzed in an optical microscope. Result: Data were subjected to statistical analysis. It was observed that the CRC group had a higher bond strength (15.29 MPa) compared to CRA group (12.41 MPa). In the analysis of fail mode, neither samples obtained adhesive fracture. In both groups, CRC (75...

Objective To verify the prevalence of dental anomalies in terms of number, position and shape, and the presence of bone alterations, through analysis of panoramic radiographs. Methods This study evaluated dental anomalies and bone alterations in children aged 6 to 12 years-old, detected on panoramic radiographies recorded in the radiographic database of the Federal University of Espírito Santo between 2012 and 2016. Clinical and demographic information were registered. Dental records were retrieved to obtain the medical history involving syndromes or other diseases that may interfere with the anomalies and alterations. Chi-square and exact Fischer’s statistical tests were performed. Results There were alterations in 83 out of 301 panoramic radiographs analyzed. There were 169 anomalies or alterations (mean of 2,04±1,38 anomalies/patient), involving 201 teeth. The most prevalent anomaly was tooth impaction (26.63%), which affected the canines more frequently, followed by hypodontia (24.26%), more often found in the second premolar, and both affected mostly females. Hyperdontia and radiolucent lesions showed the same prevalence (18.93%), the most affected teeth were those of the anterosuperior region and the first mandibular molars, respectively. The least prevalent anomalies were dilaceration (7.69%), taurodontism (2.37%) and radiopaque lesions (1.18%). Bone alterations were significantly more found in mandible and in the posterior region, which confirms the prevalence in the lower molars. Conclusion Although there was no statistically significant difference regarding sex, there was a high prevalence of anomalies and alterations in our study population, which indicates the importance of its diagnosis by means of a panoramic x-ray examination.

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