Lead deposition in bovine enamel during a pH-cycling regimen simulating the caries process.

Like fluoride, lead (Pb) accumulates on the enamel surface pre-eruptively, but it is not yet known whether it also deposits on enamel while dental caries is developing. This study evaluates Pb distribution in bovine enamel slabs submitted to a pH-cycling regimen simulating the caries process. The slabs were subjected to 8 cycles of de- and remineralizing conditions, and Pb (as acetate salt) was added to the de- and remineralized solutions at concentrations of 30 µg/l (experimental group, E1) and 300 µg/l (experimental group, E2). The control group (C) consisted of solutions to which Pb was not added. After the pH cycling, 100-µm sections of the slabs were analyzed by polarizing microscopy, to observe the extent of caries-like lesions, and these sections were used for Pb estimation by Synchrotron radiation X-ray microfluorescence. Caries lesions were observed along all superficial enamel surfaces to an extent of 120 µm. A Pb concentration gradient was observed in enamel, which decreased toward dentine. The highest Pb signals were observed for group E2, and the differences were statistically significant at enamel depths of 0 (C vs. E2; p = 0.029) and 50 µm (C vs. E2 and E1 vs. E2; p = 0.029). In conclusion, this study suggests that if Pb is present in the oral environment, it may deposit in enamel during the caries process.

Health care resource use and costs in opioid-treated patients with and without constipation in Brazil.

OBJECTIVE: To estimate the prevalence of constipation concomitant to opioid treatment and related resource use and costs from the private payer perspective. METHODS: In this retrospective database analysis, patients receiving opioid therapy were identified from a longitudinal insurance claims database. An algorithm was used to identify patients receiving opioid therapy with coincident constipation-related claims according to ICD-10 codes, targeted procedures, and opioid use criteria. Resource use and costs were determined for these individuals and compared with patients receiving opioid therapy without constipation, without opioid therapy with constipation, and without both conditions. Results were compared using analysis of variance with a significance level of 0.05. RESULTS: A total of 23,313 patients were classified as opioid-treated patients (2.2%) and 6678 of them had events related to constipation (29.0%). Compared with opioid-treated patients without constipation, incremental mean total costs per month per patient were 261.18 BRL (P < 0.001). The average cost per month for opioid-related constipation patients was 787.84 BRL, significantly higher than other patients (P < 0.001 for all comparisons). Among cancer patients, 24.4% was receiving opioids and 27.0% of those had constipation-related claims. As expected, the opioid therapy prevalence was significantly higher when compared to all patients (2.2% vs. 24.4%, P < 0.001). Cancer patients had, in average, higher costs than did noncancer patients in all four subgroups. CONCLUSIONS: Patients with constipation coincident with opioid treatment exhibited a significantly higher economic burden than did patients without the condition. These results indicate that reducing opioid-induced constipation could lead to potential cost savings for the health care system.