Prenatal vitamin D and dental caries in infants.

OBJECTIVES: Inadequate maternal vitamin D (assessed by using 25-hydroxyvitamin D [25OHD]) levels during pregnancy may affect tooth calcification, predisposing enamel hypoplasia and early childhood caries (ECC). The purpose of this study was to determine the relationship between prenatal 25OHD concentrations and dental caries among offspring during the first year of life. METHODS: This prospective cohort study recruited expectant mothers from an economically disadvantaged urban area. A prenatal questionnaire was completed and serum sample drawn for 25OHD. Dental examinations were completed at 1 year of age while the parent/caregiver completed a questionnaire. The examiner was blinded to mothers' 25OHD levels. A P value ≤ .05 was considered significant. RESULTS: Overall, 207 women were enrolled (mean age: 19 ± 5 years). The mean 25OHD level was 48 ± 24 nmol/L, and 33% had deficient levels. Enamel hypoplasia was identified in 22% of infants; 23% had cavitated ECC, and 36% had ECC when white spot lesions were included in the assessment. Mothers of children with ECC had significantly lower 25OHD levels than those whose children were caries-free (41 ± 20 vs 52 ± 27 nmol/L; P = .05). Univariate Poisson regression analysis for the amount of untreated decay revealed an inverse relationship with maternal 25OHD. Logistic regression revealed that enamel hypoplasia (P < .001), infant age (P = .002), and lower prenatal 25OHD levels (P = .02) were significantly associated with ECC. CONCLUSIONS: This study found that maternal prenatal 25OHD levels may have an influence on the primary dentition and the development of ECC.

Shear/peel bond strength of orthodontic attachments to moist and dry enamel.

INTRODUCTION: The purpose of this study was to evaluate the in-vitro shear-peel bond strength of orthodontic attachments bonded to moist and dry enamel surfaces with orthodontic resin. METHODS: Two stainless-steel mesh-based buttons were bonded to pumiced and etched enamel of each of 60 human molars mounted in cylindrical molds with Transbond XT (3M/Unitek, St Paul, Minn) (control), Smartbond (Gestenco International, Goteborg, Sweden), or Assure (Reliance Orthodontic Products, Itasca, Ill) according to each manufacturer's instructions. Half of the teeth were bonded under dry conditions, and half were given a thick layer of whole, unstimulated, fresh human saliva just before bonding. The teeth were stored in distilled deionized water at 37 degrees C. The shear-peel bond strength of 1 button on each tooth was evaluated in a testing device (Zwick, Ulm, Germany) at 24 hours; the remaining button on each tooth was evaluated at 6 months. RESULTS: Statistically significant differences (P < .05) were evident in button adhesion to the tooth surface between moisture variations for Transbond XT, but not for Assure and Smartbond. Superior bond strengths were obtained for Transbond XT on dry enamel; the bond strength of Assure to saliva-contaminated enamel was better than that of the other materials. CONCLUSIONS: Bonding to moist and dry enamel appears to be material-specific. Adequate in-vitro bonding to moist, saliva-contaminated enamel is possible with certain bonding materials.

Review of vitamin D deficiency during pregnancy: who is affected?

OBJECTIVES: Vitamin D deficiencies have been documented in several populations, including aboriginal Canadians from isolated northern communities. Such deficiencies can impact the health of both the mother and her infant. This review was performed to determine how widespread vitamin deficiency is during pregnancy. STUDY DESIGN: Electronic literature search. METHODS: A Medline search was conducted using the Mesh terms "pregnancy" and "vitamin D". Those studies meeting the inclusion criteria were reviewed. RESULTS: 35 of 76 studies reported deficient mean, or median, concentrations of 25(OH)D. Low concentrations were reported among different ethnic groups around the world. In addition, deficient concentrations were identified in 3 northern First Nations communities in Manitoba. CONCLUSIONS: Such deficiencies are of concern, as the developing fetus acquires its 25(OH)D across the placenta and may influence infant health. Future research is required to resolve the discourse surrounding ambiguous threshold values for vitamin D deficiencies and insufficiencies and to identify effective strategies to improve the vitamin D status of expectant women. Vitamin D supplementation may be necessary for many women during pregnancy, especially those in northern regions where endogenous synthesis may be constrained.

Criteria to rationalize population screening to control oral cancer.

Screening populations for the early detection of asymptomatic malignancies and potential malignancies are intuitively attractive strategies to control or reduce the burden of oral cancer on society. Subsequent preventive and/or therapeutic measures must, however, be substantiated by prospective randomized controlled trials (RCT) to markedly improve patient outcomes to reconcile such usages of 'scarce' healthcare resources. This strategic objective is more likely to be achieved by adopting the precedent established by cardiology, where prevention is emphasized over the treatment of occult lesions. For example, the screening identification of individuals at high oral carcinogenic risk will offer potential educational opportunities to change their behaviors, and/or optimize the implementation of contemporary preventive and therapeutic measures for non-compliant individuals. The imperative to substantiate the effectiveness of the screening assays (tests) by prospective RCT also cannot be ignored to safeguard the public against potential false-negative or false-positive diagnoses.