Breastfeeding, bottle feeding practices and malocclusion in the primary dentition: a systematic review of cohort studies.

The World Health Organization recommends exclusive breast feeding for at least six months. However, there is no scientific evidence of the benefits of breast feeding for oral health in children under primary dentition. This study aimed to search for scientific evidence regarding the following question: is bottle feeding associated with malocclusion in the primary dentition compared to children that are breastfed? An electronic search was performed in seven databases. The systematic review included 10 cohort studies. It was not possible to conduct meta-analysis; therefore a qualitative analysis was assessed. The majority of studies evaluated feeding habits by means of questionnaires and conducted a single examination. Three studies observed that bottle feeding was significantly associated with overjet and posterior crossbite. Studies reported several cut-off times for breastfeeding (varying from 1 month up to 3 years of age) and several types of malocclusion. Controlling for non-nutritive sucking habits was reported for only half of the studies and this may have led to biased results. The scientific evidence could not confirm a specific type of malocclusion associated with the feeding habits or an adequate time of breastfeeding to benefit the children against malocclusion. Further cohort studies are needed to confirm this evidence.

The association between occlusal factors and noncarious cervical lesions: a systematic review.

OBJECTIVES: This study aimed to systematically review the scientific evidence for the association between noncarious cervical lesions (NCCL) and occlusal risk factors (ORF) [occlusal interferences in excursive movements; occlusal force; premature contacts; type of guidance; skid of centric occlusion to maximum intercuspidation] in adults. SOURCES: Pubmed, Web of Science, Cochrane, Lilacs, Clinical Trials, National Research Register and National Institute for Health were searched. STUDY SELECTION: From 1082 potentially eligible studies, 106 were selected for full text analysis. Two independent reviewers (Kappa=0.8; p<0.001) selected the studies, abstracted information and assessed quality based on standardised scales. Six cross-sectional, two case-controls and one clinical trial were included. Several occlusal variables were analysed among the studies, but there was no standardisation of the units used in the analysis of occlusal factors. The majority of studies did not find significant associations between NCCL and ORF. Three studies found associations between NCCL and some variables (occlusal contact area, right canine guidance, premature contacts in centric relation and working side) (p<0.05). The methodological quality varied across studies, and there was high heterogeneity among them. CONCLUSION: Current scientific evidence does not support an association between ORF and NCCL. Further prospective studies with standardised methods are vital to strengthen the evidence. CLINICAL SIGNIFICANCE: Understanding the risk factors for NCCL is important to control the causes and to help the dentist choose the best approach for the patient. The evidence does not support intervention to alter some occlusal factors for the prevention or control of the progression of NCCL.

A systematic review of socioeconomic indicators and dental caries in adults.

Increasing evidence suggests that socioeconomic factors may be associated with an increased risk of dental caries. To provide better evidence of the association between dental caries in adults and socioeconomic indicators, we evaluated the relation between these two conditions in a thorough review of the literature. Seven databases were systematically searched: Pubmed, Cochrane, Web of Science, Bireme, Controlled Trials, Clinical Trials and the National Institute for Health and Clinical Excellence. No restrictions were placed on the language or year of publication. The search yielded 41 studies for systematic review. Two independent reviewers screened the studies for inclusion, extracted data and evaluated quality using the Newcastle-Ottawa scale. The following socioeconomic indicators were found: educational level, income, occupation, socio-economic status and the community index. These indicators were significantly associated with a greater occurrence of dental caries: the subject's education, subject's income, subject's occupation and the Gini coefficient. A high degree of heterogeneity was found among the methods. Quality varied across studies. The criteria employed for socioeconomic indicators and dental caries should be standardized in future studies. The scientific evidence reveals that educational level, income, occupation and the Gini coefficient are associated with dental caries.

Infant formula and enamel fluorosis: a systematic review.

BACKGROUND: Researchers have considered infant formula consumption a potential risk factor for enamel fluorosis in the U.S. population. The authors conducted a systematic review of controlled studies regarding the risk of developing enamel fluorosis associated with use of infant formula. METHODS: One reviewer independently conducted systematic searches in eight databases. The authors then abstracted information, assessed study quality and combined odds ratios (ORs), when obtainable, by using a random-effects model. RESULTS: After evaluating 969 potentially eligible published studies, the reviewers found that the authors of 41 studies had evaluated the effect of infant formula on enamel fluorosis risk. Authors of 14 of the 41 studies did not report their findings in their results. The authors of the remaining 27 published studies reported the findings of 19 observational studies; authors of 17 of these 19 studies reported ORs and, among these, infant formula consumption was associated with a higher prevalence of enamel fluorosis in the permanent dentition (summary OR 1.8, 95 percent confidence interval [CI] 1.4-2.3). There was significant heterogeneity among studies (I(2) 66 percent) and evidence of publication bias (P = .002). A metaregression analysis indicated that the ORs associating infant formula with enamel fluorosis increased by 5 percent for each 0.1-part-per-million increase in the reported levels of fluoride in the water supply (OR 1.05, 95 percent CI 1.02-1.09). CLINICAL IMPLICATIONS: Infant formula consumption may be associated with an increased risk of developing at least some detectable level of enamel fluorosis, which depends on the level of fluoride in the water supply. The evidence that the fluoride in the infant formula caused enamel fluorosis was weak, as other mechanisms could explain the observed association.

Association between breast-feeding practices and sucking habits: a cross-sectional study of children in their first year of life.

In addition to providing nutrition and immunological protection, breast-feeding has positive effects on the development of the infant's oral cavity. The aim of the present study is to assess breast-feeding patterns and to analyze the influence of breast-feeding practices and maternal sociodemographic variables on the prevalence of non-nutritive sucking habits in a sample of Brazilian infants. This cross-sectional study was carried out in Southern Brazil. A random sample of 100 mothers of infants up to 12 months of age was interviewed during the National Vaccination Campaign Day. The prevalence and median duration of breast-feeding were assessed. Breast-feeding practice, the exposure factor, was categorized as exclusive breast-feeding, predominant breast-feeding, complementary breast-feeding, or weaning. Maternal sociodemographic variables included age, race, marital status, educational level, profession, and family income. The outcome investigated was the prevalence of sucking habits (pacifier use and thumb sucking). We used two-sample tests, the chi-square test and FISHER'S EXACT TEST for statistical analyses of the data. The study revealed that 75% of infants were being breast-fed. Pacifier use and thumb sucking were common in 55%. Bottle-feeding was prevalent in 74% of infants. Breast-feeding was negatively correlated with pacifier use and thumb sucking (OR=0.11; 95% CI: 0.03 to 0.4). Bottle-feeding was strongly associated with weaning (p=0.0003). Among the sociodemographic variables, only marital status showed a statistical association with sucking habits (p=0.04). These findings suggest that breast-feeding can prevent the occurrence of sucking habits. Although we could not evaluate causality assessment, malocclusion prevention seems to be yet one more reason for promoting breast-feeding practices.