Release of leachable products from resinous compounds in the saliva of children with anterior open bite treated with spur

Abstract To evaluate the release of bisphenol-A glycidyl methacrylate (BisGMA), triethylene glycol dimethacrylate (TEGDMA), bisphenol A (BPA), and phthalates of the composite resin used in the bonding of spurs applied in the treatment of children with anterior open bite and its effects on human keratinocytes. Methodology Saliva samples of 22 children were collected before spur attachment (baseline) and 30 minutes (min) and 24 hours (h) after spur bonding. Analysis was performed using high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry (HPLC-MS/MS) and gas chromatography coupled to mass spectrometry (GC-MS). Standardized resin increments were added to three different dilutions of the cell culture medium. Keratinocytes (HaCaT) were cultivated in the conditioned media and evaluated for cell viability (MTT) and cell scratch assay. Results The levels of BisGMA (1.74±0.27 μg/mL), TEGDMA (2.29±0.36 μg/mL), and BPA (3.264±0.88 μg/L) in the saliva after 30 min, in comparison to baseline (0±0 μg/mL, 0±0 μg/mL, and 1.15±0.21 μg/L, respectively), presented higher numbers. After 24 h, the levels of the monomers were similar to the baseline. Phthalates showed no significant difference among groups. HaCat cells showed increased viability and reduced cell migration over time after exposure to methacrylate-based resin composites. Conclusion Resin composites, used to attach spurs in children with anterior open bite during orthodontic treatment, release monomers after polymerization and can influence the behavior of human keratinocytes, even at very low concentrations. Orthodontists should be aware of the risks of the resinous compounds release and preventive procedures should be held to reduce patient exposure.

Avaliação da alteração de cor de uma resina composta "beautiful bulk" submetida à imersão em soluções pigmentantes / Color change evaluation of a composite resin "beautiful bulk" submitted to immersion in pigmentant solutions

Objetivo:O objetivo do estudo foi verificar, in vitro, a alteração de cor da resina composta Beautiful-Bulk®, exposta aos líquidos pigmentantes. Métodos:Foram confeccionados 60 espécimes da resina (15,0 mm de diâmetro e 1,0 mm de espessura, n = 5) nas cores A2, B2 e C2. Os espécimes foram mantidos em uma sala escura por sete dias, em ambiente seco, a 37 °C e, em seguida, foram fotografados com aparelho celular iPhone 6S®. Os espécimes foram divididos aleatoriamente e submetidos a ciclos de imersão em quatro líquidos: água destilada (controle), suco de açaí, Coca-Cola® e molho de tomate. As imersões foram realizadas em sete e quatorze dias de forma cíclica, após a confecção dos espécimes, três vezes ao dia, durante 20 minutos. Ao fim de cada ciclo, novas fotografias foram realizadas. As imagens foram analisadas no programa Adobe Photoshop® e os dados convertidos em L*a*b através de um histograma. A variação de cor (∆E) foi analisada pela escala CIE-Lab. Resultados:A análise dos resultados (One-way ANOVA, Teste de Tukey, p < 0,05) demonstrou que o grupo controle produziu maior alteração de cor (p < 0,05) em sete e quatorze dias na cor A2. A cor B2, no ciclo de quatorze dias, apresentou maior alteração de cor (p < 0,05) para os espécimes imersos em molho de tomate sem diferença estatística (p > 0,05) do controle. Para a cor C2, os espécimes imersos em molho de tomate tiveram maior alteração de cor (p < 0,05) em sete dias. Conclusão:Conclui-se que todas as substâncias pigmentantes e a água destilada foram capazes de produzir grandes alterações de cor na resina Beautifil Bulk®. Existe uma interação significativa entre a cor da resina e agentes pigmentantes.

Aim: This study sought to verify, in vitro, the color change of the nanoparticle composite resin, Beautiful Bulk®, exposed directly to pigmented liquids. Methods: Sixty test specimens were made in a Metal matrix (15.0 mm X 1.0 mm) using composite resin (n = 5) in colors A2, B2, and C2. The specimens were photographed with a smartphone (iPhone 6S®) seven days after the preparation. The specimens were kept in the dark for seven days, dry, at 37°C. The specimens were then randomly divided and immersed in four liquids: distilled water (control), açaí juice, Coca-Cola®, and tomato sauce. The immersions were performed in seven and fourteen days cyclically, three times a day, for 20 minutes. At the end of each immersion cycle, new photographs were taken with the same smartphone. The images were analyzed in the Adobe Photoshop® program, and the data was converted to L* a* b* through a histogram. The color variation (∆E) was analyzed by the CIE-Lab scale. Results: Analysis of the results (Tukey's test, p < 0.05) showed that the control group produced a greater color change (p < 0.05) in seven and fourteen days in the A2 shade. The B2 shade, in fourteen days, showed a greater color change (p < 0.05) for the specimens immersed in tomato sauce with no statistical difference (p > 0.05) of the control. For the C2 shade, the specimens immersed in tomato sauce presented a greater color change (p < 0.05) at seven days. Conclusion: It could therefore be concluded that there is a significant interaction between the composite resin and pigment agents. All pigmented substances produced color changes in the composite resin.

Physicochemical Properties of a Methacrylate-Based Dental Adhesive Incorporated with Epigallocatechin-3-gallate

This study aimed to evaluate the influence of epigallocatechin-3-gallate (EGCG) incorporation on the physicochemical properties of a methacrylate-based dental adhesive. EGCG was added to Adper Easy One (3M-ESPE) except in control group, to obtain concentrations of 0.01% w/w and 0.1% w/w of EGCG-doped adhesives. For water sorption (WS) and solubility (SL) surveys, resin discs were assayed following ISO recommendations (n=10). The degree of conversion (DC) was analyzed by FTIR whereas flexural strength (FS) was tested by three-point bending with bar specimens (n=10). Data were subjected to one-way ANOVA and Tukey's test (p<0.05). No significant difference in the DC, WS and FS were found between the different concentrations of EGCG (p>0.05). Adhesives containing 0.1% or 0.01% of EGCC demonstrated similar values of SL (p>0.05) and higher than those found for adhesive without EGCC (p<0.05). In conclusion, the addition of EGCC to adhesive reduced the solubility without affecting the other evaluated properties.

Esse estudo teve como objetivo avaliar a influência da incorporação de epigalocatequina-3-galato (EGCG) nas propriedades físico-químicas de um sistema adesivo à base de metacrilato. O EGCG foi adicionado ao Adper Easy One (3M-ESPE), exceto para o grupo controle, para a obtenção das concentrações de 0,01% e 0,1% p/p. No ensaio de sorção (S) e solubilidade (SL), foram confeccionados discos de resina de acordo com as recomendações da ISO (n=10). O grau de conversão (GC) foi analisado através de FTIR, enquanto a resistência flexural (RF) foi avaliada em teste de flexão de três pontos com espécimes em forma de barra (n=10). Os dados foram submetidos à Análise de Variância a um critério e teste de Tukey (p<0,05). Não houve diferença significativa entre as concentrações de EGCG testadas no GC, SL e RF (p>0,05). Adesivos contendo EGCG a 0,1% ou 0,01% apresentaram valores similares de SL (p>0,05) e maiores do que os valores obtidos pelo adesivo não incorporado por EGCG. Conclui-se que a adição de EGCG ao adesivo reduziu a solubilidade sem afetar as outras propriedades avaliadas.

Effectiveness of different removal methods of artificially demineralized dentin / Efetividade de diferentes métodos de remoção de dentina desmineralizada artificialmente

Objective: This study aimed to evaluate the effectiveness of different mechanical methods for the removal of demineralized dentin. Methods: Healthy human third molars were prepared in such a way that the flat occlusal surfaces of the dentin were exposed and longitudinally sectioned in a vestibular-lingual direction. One section of each tooth was submitted to the pH-cycling model, while the other section was kept intact. The tooth sections were joined, and a single operator performed dentin removal using a steel bur, a hand instrument,or a polymer bur. The tooth’s sections were then separated, and digital images were obtained. The depth of the prepared cavities and the microhardness measurements were checked and analyzed statistically using the Kruskal-Wallis One-Way ANOVA in Ranks, the Tukey test, while desmineralized dentin were comparedusing the One-Way ANOVA, and the Holm-Sidak method (p < 0.05). Results: The steel bur produced the deepest cavities in mineralized and demineralized dentin. The polymer bur generated the shallowest cavitiesin demineralized dentin. The measurements of microhardness of the deepest surfaces of the cavities prepared in demineralized dentin indicated that the steel bur and hand instrument presented similar values, while those values produced by polymer burs proved to be lower. Conclusion: The effectiveness of the removalof demineralized dentin varied among the three methods used in this study. The polymer bur proved to bethe most conservative of the methods used. By contrast, the steel bur and hand instrument showed a similareffectiveness in the removal of dentin, according to the microhardness of the remaining dentin, even thoughthey produced different cavity depths.

Isolamento do Campo Operatório: Panorama de Utilização em Consultórios e Clínicas Privadas de Belo Horizonte, MG, Brasil / Rubber Dam: Use in Private Clinics in Belo Horizonte, MG, Brazil

Objetivo: verificar a utilização de isolamento em consultórios e clínicas privadas em Belo Horizonte, observando-se: tipo, procedimentos executados com isolamento e o motivo da escolha; além de fatores como: tempo de formação dos cirurgiões-dentistas (CDs), classe econômica dos pacientes e presença de pessoal auxiliar (ASB). Método: a amostra elegível foi formada por CDs atuantes na região Centro-Sul da cidade. A amostra final de conveniência foi de 115 CDs que responderam a um instrumento de coleta de dados com questões descritivas e objetivas. Os dados foram analisados descritivamente e pelo teste Qui-quadrado (p≤0,05).Resultados: dos CDs que participaram da pesquisa, 55% eram do gênero feminino; 63,5% tinham entre 23 e 35 anos; 39% tinham menos de cinco anos de atividade profissional e 59% eram especialistas. Eram da região Central 69% e Sul 31%; têm ASB 66% dos CDs. Os pacientes foram classificados em classe econômica A (11%), B (30%), C (34%), D (16%) e E (9%). Relataram utilizar algum tipo de isolamento 82% dos CDs (36% relativo; 28% absoluto; e 36% ambos). O grau de aceitação dos pacientes quanto aos métodos de controle de umidade foi considerado alto para 52% dos CDs. O principal motivo para escolha doisolamento absoluto foi o controle de infecção (27%) e para o relativo foi a praticidade (24%). O isolamento absoluto é utilizado principalmente na endodontia (38%) e o relativo em restaurações (33%). Gênero (p=0,6483), tempo de atividade (p=0,2576), especialidade (p=0,0733) e presença de ASB (p=0,4127), não influenciaram significativamente na escolha do tipo de isolamento. Conclusão: a maioria dos CDs relatou utilizar algum tipo de isolamento do campo operatório e aponta como principais vantagens a biossegurança, a praticidade e melhor qualidade dos procedimentos executados

Objective: The aim of this study was to investigate the use of isolation in offices and private clinics in Belo Horizonte, it was observed: the type, procedures performed in isolation and the reason for their choices. In addition to those factors were also observed the duration of the dentistsÆ training, the patientsÆ economic class and the presence of an office assistant.Method: The eligible sample consisted of active dentist in the southcenter region of the town. The final sample of convenience was 115 professionals who answered to an instrument data collection with descriptive and objective questions. The results were analyzed descriptively and by Qui-Square test (p≤0,05).Results: Among the dentist in the survey 55% were female, 63.5% were between 23 and 35 years old, 39% had less than five years of professional activity and 59% were specialists; 69% were from the central region and 31% from the south; 66% of the dentists have assistant in office. Patients were classified according to their economic class; class A (11%), B (30%), C (34%), D (16%) and E (9%). 82% of the dentists reported the use of some type of insulation, (36% relative, 28% absolute, and 36% both). The degree of the patientsÆ acceptance to methods of moisture control was considered high, for 52% of the professionals. The main reason for choosing the absolute isolation was the control of infection (27%) and the relative was the practicality (24%). The rubber dam is mainly used in endodontics (38%) and the relative isolation is used in restorations (33%). The gender (p=0.6483), professional activity time (p=0.2576), training (p=0.0733) and presence of an office assistant (p=0.4127) havenÆt significant influence in the type of isolation choice. Conclusion: The most of dentists reported using some type of isolation of the operative field and indicated that the main advantages are the biosafety, practicality and quality of procedures performed