Childhood polybrominated diphenyl ether (PBDE) exposure and executive function in children in the HOME Study

Prenatal exposure to polybrominated diphenyl ethers (PBDEs) have been reported to impair executive function in children, but little is known whether childhood PBDE exposures play a role. Using the Health Outcomes and Measures of the Environment (HOME) Study, a prospective birth cohort in the greater Cincinnati area, we investigated the association between repeated measures of PBDEs during childhood and executive function at 8 years in 208 children and whether effect modification by child sex was present. We used child serum collected at 1, 2, 3, 5, and 8 years to measure PBDEs. The Behavior Rating Inventory of Executive Function was completed by parents to assess executive function at 8 years. We used multiple informant models to examine childhood PBDEs during several exposure windows. Null associations were observed between early childhood PBDEs and executive function. However, we observed significant adverse associations between a 10-fold increase in concurrent concentrations of BDE-28 (β = 4.6, 95% CI 0.5, 8.7) and BDE-153 (β = 4.8, 95% CI 0.8, 8.8) with behavioral regulation. In addition, PBDEs at 8 years were significantly associated with poorer emotional and impulse control. No associations were noted between childhood PBDEs and metacognition or global executive function. However, child sex significantly modified the associations, with significantly poorer executive function among males with higher concurrent BDE-153, and null associations in females. Our study findings suggest that concurrent PBDE exposures during childhood may be associated with poorer executive function, specifically behavior regulation. Males may also be more sensitive to adverse associations of concurrent PBDEs on executive function.     

Incidence of dental anxiety in young adults in relation to dental treatment experience

OBJECTIVES: To document the incidence of dental anxiety among individuals aged 18 years at baseline and 26 years at follow-up, and to determine if dental treatment experience continues to play a significant etiological role with respect to the onset of dental anxiety in young adults. METHODS: Dental anxiety scale (DAS; Corah, 1969) scores at ages 15, 18 and 26 were obtained for Study members in the Dunedin Multidisciplinary Health and Development Study. Dental examinations were conducted, and sociodemographic and dental service-use data were collected using a self-report questionnaire. Using a case definition of a DAS score of 13 or more, age 18-26 incident cases were identified and their dental treatment experience and service-use characteristics compared with the remainder. RESULTS: DAS scores at 18 and 26 were available for 792 (80.8%) of the 980 26-year-old Study members. An increase in dental anxiety prevalence was observed over the eight-year period, with an annualized incidence of 2.1%. Fewer incident cases had visited a dentist in the previous eight years, and there were no differences between incident cases and others in their eight-year DFS, FS or tooth-loss increments. A subgroup of "recurrent" cases was identified who were dentally anxious at 15 and 26 but not at 18, and their eight-year incidence of tooth loss due to caries was substantially higher than non-cases. CONCLUSIONS: Aversive conditioning experiences appear to be unrelated to the adult onset of dental anxiety, and it may be that particular temperamental or psychological traits are associated with the condition.     

Caries increment in the permanent dentition of Mexican children in relation to prior caries experience on permanent and primary dentitions

OBJECTIVE: To evaluate the likelihood of caries increment in schoolchildren, based on their prior caries experience. MATERIAL AND METHODS: We undertook a longitudinal study in 452 six-to-nine year olds between 1999 and 2001 in Mexico, with dental exams conducted by two standardized examiners (kappa>0.85). The dependent variable was the DMFT increment, dichotomized as without increment, and at least one unit of increment. Independent variables estimated caries experience at baseline. Data were analyzed using non-parametric tests and generalized linear models (log-binomial) to calculate relative risk (RR) adjusted for age and sex. RESULTS: The percentage of caries-free children diminished by 20.5% from 1999 to 2001. DMFT index increased two-fold, from 0.25+/-0.70 in 1999 to 0.77+/-1.30 in 2001 (p<0.001). The overall risk for this sample was 24%. The DMFT increment was higher (p<0.001) in children with DMFT>0 and dmft>0 in 1999 (RR=1.89, 95% CI=1.37-2.62; RR=2.71, 95% CI=1.94-3.76, respectively). The likelihood for DMFT increment from the 1999 levels was: (1) 2.78 times higher (95% CI=2.06-3.76) if schoolchildren had caries in any of the first permanent molars and (2) 1.62 times higher (95% CI=1.20-2.19) if schoolchildren were affected by high severity caries at baseline. CONCLUSIONS: Both caries prevalence and mean DMFT had significant increments in 18 months. Dental caries in the primary (dmft) and permanent (DMFT) dentitions at baseline are goods indicators of subsequent caries development in this group of children in a medium income country. This relationship became stronger when the occurrence of caries in the first permanent molars was included.     

Traumatic injuries to the primary dentition and effects on the permanent successors – a clinical follow-up study

Abstract –  This study investigated problems in the permanent dentition that, according to history and records, were attributable to dental alveolar injuries of the primary dentition. 106 children have been involved in the study, who had experienced primary anterior tooth trauma affecting a total of 200 teeth. Thirty-nine patients (81 teeth) were available for follow-up examinations. In 25% of the cases followed up, damage was found on the successors in the secondary dentition (16 children/20 teeth). In half of the cases, a comparatively mild form of lesion like enamel discoloration was observed. This was the result of an injury during the tooth maturation process causing enamel hypoplasia. Clinically more relevant were the dental deformities: cessation of root formation or retention caused by ankylosis, which made up the remaining 50% of cases. This was confirmed by clinical long-term observation. The different effects on the permanent teeth can only be detected by radiography after an interval of several months or may even be clinically assessed only after the eruption of the clinical crown.     

Contribution of the periosteum to bone formation in guided bone regeneration. A study in monkeys

The periosteum has been referred to as a protective barrier in the regeneration of bone defects. The objective of this study was to determine the contribution of periosteum as a natural barrier to bone formation in guided bone regeneration. Mucoperiosteal flaps were elevated bilaterally on the buccal aspect of the mandibular angle in 5 cynomolgus monkeys. Bleeding was induced by perforating the cortical bone. A hemispherical titanium mesh was fixed over the areas thus creating a void 5 mm in height between the mesh and the bone surface. One one side the mesh was covered with an ePTFE membrane (test side). The contralateral side did not receive further treatment (control side). After 4 month healing, histomorphometric analyses were used to determine the percentage of new bone in the void underneath the mesh, and the ratio between mineralized tissue and marrow spaces in new and old bone. The mean percentage of new bone tissue was 77.2 +/- 7.5% for the test sides and 68.6 +/- 8.4% for the control sides (P = 0.018, t-test). This new bone contained 80.0 +/- 3.6% mineralized tissue in the test group and 82.5 +/- 5.0% in the control group (P > 0.05, t-test). In both groups the newly formed bone exhibited significantly less mineralized tissue than the old bone (P < 0.05, t-test). It is concluded from this study that new bone formation was enhanced by the additional use of an ePTFE membrane under a periosteum-lined mucoperiosteal flap when space maintenance was excluded as a critical factor.     

Effects of smoking and drinking habits on the incidence of periodontal disease and tooth loss among Japanese males: a 4-yr longitudinal study

OBJECTIVE: We investigated the risk of periodontal disease and tooth loss, associated with habits of smoking and alcohol consumption, in a longitudinal study. SUBJECTS AND METHODS: The subjects were 1332 Japanese males, 30-59 yr of age, who were free from periodontal disease at the baseline check-up, and who underwent a second check-up 4 yr later. Periodontal disease was diagnosed using the community periodontal index score, based on the clinical probing of pocket depth (> or = 4 mm). Smoking and alcohol consumption patterns were evaluated using a self-administered questionnaire. RESULTS: A dose-response relationship was observed between the amount of smoking and the incidence of periodontal disease in each age group. The overall odds ratios (95% confidence intervals), adjusted for age and alcohol, were 1.51 (0.95-2.22), 1.58 (1.13-2.22) and 2.81 (1.96-4.03), among smokers consuming 1-19, 20 or 21 or more cigarettes per day, respectively, with a significant linear trend (p < 0.0001). A similar association was found between smoking and tooth loss, except for the 50-59-yr-old age group. The adjusted odds ratios were 1.26 (0.60-2.64), 2.01 (1.21-2.32) and 2.06 (1.23-3.48), respectively. A significant linear trend between smoking and tooth loss was also observed (p = 0.01). Ex-smokers showed no significant difference compared with nonsmokers. We also found a significant linear trend between alcohol consumption and tooth loss among 30-39-yr-old subjects, while no relationship was observed between alcohol consumption and periodontal disease. CONCLUSION: Cigarette smoking was found to be an independent risk factor for periodontal disease and tooth loss. Alcohol consumption was a limited risk factor for tooth loss in the younger age group, but was unrelated to periodontal disease. To prevent periodontal disease and tooth loss, health practitioners need to encourage people to stop smoking or not to start.     

Short-term anti-plaque effect of two chlorhexidine varnishes

BACKGROUND: Chlorhexidine (CHX) varnishes have been mainly used for the prevention of caries in high-risk populations. Reports regarding their anti-plaque effect on a clinical level are limited to non-existing as opposed to their microbiological impact on plaque formation. AIM: The aim of this preliminary investigation was to evaluate the anti-plaque effect of two CHX varnishes applied on sound enamel in relation to a positive control, a negative control and to one another. METHODS: Sixteen healthy subjects volunteered for this randomized-controlled, single-blind, four-treatment-four-period crossover-designed clinical trial. A 3-day plaque re-growth model was used to determine de novo plaque accumulation following CHX rinsing, Cervitec application, EC40 application and no therapy. The amount of plaque was measured using the Quigley and Hein plaque index and "automatic image analysis" (AIA). RESULTS AND CONCLUSIONS: Varnish treatment resulted in significantly higher plaque levels than CHX rinsing irrespective of the varnish that was used (p< or =0.002), implying that the latter is likely to remain the gold standard as an anti-plaque agent. However, highly significant differences were also found in favour of both varnish systems when compared with no therapy (p<0.001), which indicates that varnish treatment is an effective means of inhibiting plaque formation in a short time span. Cervitec exhibited slightly, yet significantly, higher plaque levels in comparison with EC40 as determined by AIA (p=0.006). Large-scale trials with a longer observation period are necessary to substantiate these results.     

Sinus floor augmentation using large (1-2 mm) or small (0.25-1 mm) bovine bone mineral particles: a prospective, intra-individual controlled clinical, micro-computerized tomography and histomorphometric study

Objectives: To compare the amount of newly formed bone after sinus floor augmentation with two different particle sizes of bovine bone mineral (BBM) using clinical, micro‐computerized tomography (CT) and histological techniques. Methods: Bilateral sinus floor augmentations were performed in 10 patients. Six to 9 months later, bone samples were retrieved and analyzed. Results: Results: Both groups were not different in vertical bone height achieved after augmentation, post‐operative complications and maximal torque for the insertion of implants. Micro‐CT measurements could not detect a statistically significant difference in bone volume between the groups (with a tendency for new more bone in the small granules group). Histomorphometric analysis revealed that both granule sizes produced the same pattern of bone formation, surrounding the graft granules, and producing a shape of a network, “bridging” between the BBM particles. Multi‐nucleated giant cells, probably osteoclasts, were observed directly on the BBM particle surface in both groups. The osteoclast‐like cells preferred the small‐size BBM particles and not the large particles both in the small‐size and the large‐size granules group. Conclusion: Both sizes of BBM granules preformed equally and achieved the aim of the sinus floor augmentation procedure clinically and histologically. To cite this article:
Chackartchi T, Iezzi G, Goldstein M, Klinger A, Soskolne A, Piattelli A, Shapira L. Sinus floor augmentation using large (1–2 mm) or small (0.25–1 mm) bovine bone mineral particles: a prospective, intra‐individual controlled clinical, micro‐computerized tomography and histomorphometric study.
Clin. Oral Impl. Res 22 , 2011; 473–480
doi: 10.1111/j.1600‐0501.2010.02032.x