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.

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.

Effects of high-dose bisphenol A on the mouse oral mucosa: A possible link with oral cancers.

Bisphenol A (BPA) is an endocrine disrupting chemical able to promote hormone-responsive tumors. The major route of BPA contamination being oral, the aim of the present study was to investigate BPA effects on oral cells. Here, we evaluated the impact of sub-chronic in vivo exposure to BPA and its in vitro effects on neoplastic and non-neoplastic oral cells. We evaluated the oral mucosa of mice chronically exposed to BPA (200 mg/L). The response of keratinocytes (NOK-SI) and Head and Neck (HN) Squamous Cell Carcinoma (SCC), HN12 and HN13 cell lines to BPA was examined. In vivo, BPA accumulated in oral tissues and caused an increase in epithelial proliferative activity. BPA disrupted the function of keratinocytes by altering pro-survival and proliferative pathways and the secretion of cytokines and growth factors. In tumor cells, BPA induced proliferative, invasive, pro-angiogenic, and epigenetic paths. Our data highlight the harmful effects of BPA on oral mucosa and, tumorigenic and non-tumorigenic cells. Additionally, BPA may be a modifier of oral cancer cell behavior by prompting a functional shift to a more aggressive phenotype.

Saliva biomonitoring using LPME-GC/MS method to assess dentistry exposure to plasticizers.

Bisphenol A and phthalates are endocrine disruptors widely used as chemical additives mainly in plastic products, including materials for dentistry procedures. Besides, many plasticizers have been associated with important diseases requiring performed methods for their quantification. In the present study, an alternative method for the determination of bisphenol A (BPA) and phthalate metabolites in saliva was developed and validated using hollow fiber liquid phase microextraction (HF-LPME) for sample preparation and gas chromatography coupled to ion trap mass spectrometry (GC/MS) for analysis. A mixture of octanol and ethyl octanoate (1:1 v/v) was used as an acceptor phase in hollow fiber to extract the analytes from saliva samples. A Doehlert design was performed to optimize the variable sample agitation and extraction time. The HF-LPME-GC/MS method developed for saliva analysis showed good selectivity, linearity (R2 > 0.900), and precision (CV = 0.86-18.68%). Limits of detection and quantification ranged from 0.03 to 0.53 µg L-1 and 0.09 to 1.78 µg L-1, respectively. A high concentration of BPA in the oral cavity and oropharyngeal space is a warning of the possible association with the main cancer of the mouth. The method developed and validated was applied to patients with oral squamous cell carcinoma (study group, n = 16) and patients who did not present any oral lesion (control group, n = 16). A principal component analysis was performed and showed a tendency for the association between oral squamous cell carcinoma (OSCC) and plasticizers. Graphical abstract.