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

BACKGROUND: 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.

Evaluation of periodontal parameters and gingival crevicular fluid cytokines in children with anterior open bite receiving passive orthodontic treatment with a spur.

Objective: To evaluate clinical parameters and gingival crevicular fluid (GCF) cytokines in children with anterior open bite receiving passive orthodontic treatment with spurs. Methods: Twenty children with indications for interceptive orthodontic treatment, an anterior open bite, and good oral hygiene and periodontal health were included in this study. GCF samples were collected from the mandibular and maxillary central incisors before (baseline) and 24 hours and 7 days after spur bonding. Clinical and periodontal examinations and cytokine analyses were performed. Results: At 7 days after spur attachment, gingival bleeding in the mandibular group was increased relative to that in the maxillary group. Visible plaque was correlated with gingival bleeding at 7 days and the GCF volume at 24 hours after spur attachment. Compared with those at baseline, interleukin (IL)-8 levels in the maxillary group and IL-1ß levels in both tooth groups increased at both 24 hours and 7 days and at 7 days, respectively. At 24 hours, IL-8, IL-1ß, and IL-6 levels were higher in the maxillary group than in the mandibular group. Cytokine production was positively correlated with increased GCF volume, but not with gingival bleeding, visible plaque, or probing depth. Conclusions: Although orthodontic treatment with spurs in children resulted in increased gingival bleeding around the mandibular incisors, IL levels were higher around the maxillary incisors and not correlated with periodontal parameters. Increased cytokine levels in GCF may be associated with the initial tooth movement during open bite correction with a passive orthodontic appliance in children.

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.

Efeitos da colagem do esporão lingual no microambiente periodontal e liberação de subprodutos de materiais resinosos no tratamento de mordida aberta anterior em crianças / Effects of lingual sporing collage on the periodontal micro-environment and release of by-products of resin materials on the treatment of anterior open bite in children

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.