Is there an association between bruxism and intestinal parasitic infestation in children?

PURPOSE: Multiple factors have been considered in the etiology of bruxism in pediatric patients, among which are infestations by intestinal parasites suggested by some authors. No empirical evidence exists, however, of such association. Therefore, this study's purpose was to investigate the existence of an association between bruxism and intestinal parasitic infestation in children. METHODS: Fifty-seven 6- to 11-year-olds (30 cases and 27 controls) who had not used anthelminthics 2 months before the baseline examination were enrolled in the study. A diagnosis of bruxism was based on an intraoral clinical examination performed by a single trained examiner and on the parent/guardian's report of any perceived parafunctional habits (questionnaire-based interview). Bruxism cases were defined as those children with a report of currently perceived habits of eccentric or centric bruxism (tooth-grinding and tooth-clenching, respectively) combined with clinical evidence of nonphysiologic wear facets. The volunteers were required to collect 3 fecal samples (1 every 2 to 3 days). Parasitologic analysis was performed using the spontaneous sedimentation method. Data gathered from the intraoral clinical examination, questionnaire, and parasitologic analysis were tabulated and submitted to statistical analysis using the chi-square test and student's t test. RESULTS: Intestinal parasitic infestation was observed in 30% (N=9) of cases and 41% (N=11) of controls, but no statistically significant association was observed (P=.40). CONCLUSION: This study's findings do not support the existence of an association between intestinal parasitic infestation and bruxism among the evaluated pediatric population.

Lead contents in the surface enamel of deciduous teeth sampled in vivo from children in uncontaminated and in lead-contaminated areas.

This study aimed to: (1) measure lead contents in the surface enamel of two populations consisting of 4-6-year-old children, one from an apparently uncontaminated area (Ribeirão Preto, São Paulo State, SP, Brazil, n=247) and the other from an area notoriously contaminated with lead (Bauru, São Paulo State, Brazil, n=26); (2) compare biopsy depths between the two populations; (3) correlate biopsy depth with lead content; (4) stratify samples according to biopsy depth to compare lead contents in samples from similar biopsy depths. A surface enamel acid-etch microbiopsy was performed in vivo on a single upper deciduous incisor for each sample. Lead was measured by graphite furnace atomic absorption spectrometry (GFAAS) while phosphorus was measured colorimetrically to establish biopsy depth. Samples from both populations were classified into categories of similar biopsy depths based on biopsy depth quartiles. Median lead contents were statistically different between the Ribeirão Preto population (206 microg/g, range: 5-1399 microg/g) and the Bauru population (786 microg/g, range: 320-4711 microg/g) (p<0.001); however, biopsy depth did not differ between the Ribeirão Preto (3.9 microm, Standard Deviation, SD=0.9) and Bauru (3.8 microm, SD=0.9) populations (p=0.7940). Pearson's correlation coefficient for biopsy depths versus log10 lead values was -0.29 for Ribeirão Preto and -0.18 for Bauru. Lead contents were statistically different between the two populations for all quartiles of biopsy depth. These findings suggest that lead accumulated in the surface enamel of deciduous teeth is linked to the environment in which people reside, indicating that this tissue should be further explored as an accessible biomarker of lead exposure.

In vivo studies on lead content of deciduous teeth superficial enamel of preschool children.

The amount of lead in the superficial enamel of deciduous teeth from 4- and 5-year-old children was determined by means of an enamel biopsy followed by lead analysis by graphite furnace atomic absorption spectrometry. Children examined in this study (n=329) attended public preschools in the city of Piracicaba, SP, Brazil. The selection of preschools was based on geographical location: some were located in an industrial area of the city, whereas others were located in an area devoid of industries. The objectives of this study were (1) to test whether enamel biopsies were an appropriate method for lead content population screening in young children; (2) to verify the lead content of superficial enamel of preschool children's deciduous teeth and to compare the results obtained from children exposed to different environments; (3) to analyze how biopsy depth correlated with lead content and affected comparisons between groups. An adhesive tape with a central hole (diameter=1.6 mm) was placed on one of the upper central incisors. Five microliters of 1.6 M l(-1) HCl in 70% glycerol (v/v) were applied to this area for 20 s, followed by a rinse with 5-microl ultrapurified water for 10 s. It was shown that the technique was feasible for population studies on young children. The lead concentration in enamel biopsies from the industrial area children (median: 169 ppm Pb) was significantly higher than that from the children living far from industries (118.1 ppm Pb) (P<0.0001). Analysis of the data showed that biopsies deeper than 3.9 microm gave more reliable results for comparisons between groups. To our knowledge, this study is the first to use an enamel microbiopsy to characterize a large sample of young children in vivo for lead monitoring in teeth.