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Data in this article are associated with our research article "Dental Resin Monomers Induce Early and Potent Oxidative Damage on Human Odontoblast-like Cells." Dental adhesives are polymeric compounds consisting of several chemical substances, including resin monomers, such as 2-hydroxyethyl methacrylate (HEMA) and triethylene glycol dimethacrylate (TEGDMA), together with other comonomers, making up the organic matrix of the adhesive and whose composition is based on the methyl methacrylate chemistry. The release of residual monomers, susceptible to biodegradation, acts as a source of bioactive compounds, which can interact with tissues and induce a cytotoxic cellular response. The most used techniques to evaluate cytotoxicity, proliferation, or metabolic activity of cells exposed to different substances, are MTT and resazurin. Each chemistry evaluates cell viability differently, so the data obtained could vary depending on the technique sensitivity to detect changes in cell metabolism. The objective of this article was to present viability data as a function of the metabolic activity in human odontoblast-like cells (hOLCs), exposed to 3, 6, 9, and 12 mM HEMA, or 0.75, 1.5, 3, and 6 mM TEGDMA evaluated by the MTT, and resazurin techniques in the first 24 hours of exposure, at different time points. The absorbance data for the MTT test and the fluorescence intensity for the resazurin test were obtained by spectrometry. SIMSTAT software 2.6.5 for Windows was used to confirm the normal data distribution (Levene's test). Subsequently, an analysis of variance (one-way ANOVA) was performed to compare the control with each HEMA and TEGDMA concentration. Where a p < 0.05 indicated a high F value, a Fisher's least significant differences post-hoc analysis was performed, using an alpha value < 0.05. Data from the different time points were compared with a Student's t-test for each concentration. These data may be useful to compare the cytotoxic response of hOLCs with other cell types or the cell response to other resin monomers.
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Introdução: O aparelho ortodôntico passivo esporão é um método utilizado em crianças para correção de mordida aberta anterior. Para realizar a fixação desses acessórios dentes é necessário a utilização de materiais resinosos que podem liberar subprodutos tóxicos como BisGMA e TEGDMA. Além disso, a movimentação dentária ortodôntica pode aumentar a concentração de interleucinas no fluido crevicular gengival (FCG). A liberação de subprodutos resinosos no tratamento de mordida aberta e o comportamento da expressão de interleucinas ainda não estão elucidados na literatura. Objetivo: (1) avaliar a expressão de citocinas no FCG em crianças com mordida aberta que receberam fixação de esporão como tratamento e (2) quantificar o BisGMA e TEGDMA na saliva desses pacientes; e (3) avaliar a migração e viabilidade de quetarinócitos humanos expostos à resina. Métodos: Foram selecionados pacientes da clínica da FO-UFMG que apresentaram mordida aberta anterior. A colagem dos esporões foi realizada e os excessos de resina foram removidos. Foram realizados exames clínico e periodontal nos incisivos superiores e inferiores, coletas do FCG (antes da colagem baseline, 24 h e 7 d após) e saliva (baseline, 30 min, 24 h e 7 d após a colagem). As citocinas do FCG foram analisadas por meio do BD™ Cytometric Bead Array e as amostras de saliva, através do método de cromatografia líquida de alta eficiência. Para as análises in vitro, células imortalizadas HaCat foram tratadas com meio de cultura condicionados com incrementos do sistema resinoso em 3 diferentes diluições e posteriormente foram realizados os testes de viabilidade e migração celular. Resultados: O estudo in vivo demonstrou que houve aumento do sangramento gengival nos incisivos inferiores após 7d quando comparados ao baseline e que este índice estava maior nos dentes inferiores do que nos superiores. Em 24h e 7d após a fixação do esporão, os níveis de IL-8 nos incisivos superiores estavam aumentados. Em 7d, a concentração de IL-1ß foi aumentada em comparação ao baseline nos dois grupos de dentes. Comparando os incisivos superiores e inferiores, os níveis de IL-8, IL-1ß e IL-6 foram maiores nos superiores às 24h. A produção de citocinas pôde ser positivamente correlacionada com o aumento do volume do FCG. Houve aumento dos níveis de BisGMA e TEGDMA na saliva em 30min, com redução dos níveis em 24h e 7d. Os resultados in vitro demonstraram aumento da migração celular nos queratinóscitos expostos aos meios condicionados mesmo em baixas concentrações .Conclusão: Foi identificado que após a colagem do esporão lingual ocorreu o aumento na expressão de interleucinas no FCG. Além disso, foi possível identificar a liberação de subprodutos resinosos na saliva das crianças. Embora os mesmos possam interferir na migração celular, não há estudos que quantifiquem a exposição mínima capaz de induzir alterações no indivíduo. Sendo assim, os benefícios da colagem do esporão sobrepõem seus efeitos adversos
Introduction: The passive spur orthodontic appliance is a method used in children to correct anterior open bite. To fix these teeth accessories, it is necessary to use resinous materials that can release toxic by-products such as BisGMA and TEGDMA. In addition, orthodontic tooth movement can increase the concentration of interleukins in the gingival crevicular fluid (FCG). The release of resinous by-products in the treatment of open bite and the behavior of interleukin expression are not yet elucidated in the literature. Objective: (1) to evaluate the expression of cytokines in the FCG in children with open bite who received spur fixation as treatment and (2) to quantify the BisGMA and TEGDMA in the saliva of these patients; and (3) evaluate the migration and viability of human ketarinocytes exposed to the resin. Methods: Patients from the FO-UFMG clinic who presented anterior open bite were selected. The spurs were bonded and the excess resin was removed. Clinical and periodontal examinations were performed on the upper and lower incisors, collections of the FCG (before bonding - baseline, 24 h and 7 d after) and saliva (baseline, 30 min, 24 h and 7 d after bonding). The FCG cytokines were analyzed using the BD ™ Cytometric Bead Array and the saliva samples, using the high performance liquid chromatography method. For in vitro analysis, immortalized HaCat cells were treated with culture medium conditioned with increments of the resin system in 3 different dilutions and then the viability and cell migration tests were performed. Results: The in vivo study showed that there was an increase in gingival bleeding in the lower incisors after 7d when compared to the baseline and that this index was higher in the lower than in the upper teeth. At 24h and 7d after spur fixation, IL-8 levels in the upper incisors were increased. At 7d, the concentration of IL-1ß was increased compared to the baseline in the two groups of teeth. Comparing the upper and lower incisors, the levels of IL-8, IL-1ß and IL-6 were higher in those above 24h. Cytokine production could be positively correlated with increased FCG volume. There was an increase in the levels of BisGMA and TEGDMA in saliva in 30 minutes, with a reduction in levels in 24h and 7d. The in vitro results demonstrated an increase in cell migration in keratinocytes exposed to conditioned media even in low concentrations. Conclusion: It was identified that after the gluing of the tongue spur there was an increase in the expression of interleukins in the FCG. In addition, it was possible to identify the release of resinous by-products in children's saliva. Although they can interfere with cell migration, there are no studies that quantify the minimum exposure capable of inducing changes in the individual. Therefore, the benefits of spur bonding override its adverse effects.