Aim: The objective of this systematic review was to investigate whether breastfeeding decreases the risk of malocclusions.Methods: Six databases were systematically searched to the end of October 2014. Observational and interventional studies were included. Breastfeeding was evaluated in three categories: (i) ever versus never; (ii) exclusive versus absence of exclusive; and (iii) longer periods versus shorter periods. All types of malocclusion were considered as the outcome. Pooled adjusted odds ratio and its 95% confidence interval (95%CI) were obtained from meta‐analyses. Heterogeneity was assessed with both the Q‐test and the I‐square. Funnel plots and Egger's test were employed to assess publication bias.Results: Forty‐eight studies were included in the systematic review, and 41 were included in the overall meta‐analysis (n = 27 023 participants). Subjects who were ever breastfed were less likely to develop malocclusions than those never breastfed (OR 0.34; 95% CI 0.24; 0.48), those who were exclusively breastfed presented lower risk to present malocclusion than those with absence of exclusive breastfeeding (OR 0.54; 95% CI 0.38; 0.77), and subjects longer breastfed were less likely to have malocclusions than those shorter breastfed (OR 0.40; 95% CI 0.29; 0.54).Conclusion: Breastfeeding decreases the risk of malocclusions.

BACKGROUND: Few studies have assessed the effect of breastfeeding, bottle feeding, and sugar consumption on children’s dental caries. We investigated whether the duration of breastfeeding is a risk factor for dental caries in the primary dentition, independently of sugar consumption. METHODS: An oral health study (n = 1303) nested in a birth cohort study was carried out in southern Brazil. The average number of decayed, missing, and filled primary tooth surfaces (dmfs) and severe early childhood caries (S-ECC: dmfs ≥6) were investigated at age 5 years. Breastfeeding was the main exposure collected at birth and at 3, 12, and 24 months of age. Data on sugar consumption were collected at 24, 48, and 60 months of age. Marginal structural modeling was used to estimate the controlled direct effect of breastfeeding (0–12, 13–23, and ≥24 months) on dmfs and on S-ECC. RESULTS: The prevalence of S-ECC was 23.9%. The mean number of dmfs was 4.05. Children who were breastfed for ≥24 months had a higher number of dmfs (mean ratio: 1.9; 95% confidence interval: 1.5–2.4) and a 2.4 times higher risk of having S-ECC (risk ratio: 2.4; 95% confidence interval: 1.7–3.3) than those who were breastfed up to 12 months of age. Breastfeeding between 13 and 23 months had no effect on dental caries. CONCLUSIONS: Prolonged breastfeeding increases the risk of having dental caries. Preventive interventions for dental caries should be established as early as possible because breastfeeding is beneficial for children’s health. Mechanisms underlying this process should be investigated more deeply.

Breastfeeding is a powerful health-promoting behavior. A 2016 Lancet global collaboration to review the health implications of breastfeeding was among the first to consider oral health outcomes. While a role was suggested for breastfeeding in preventing malocclusion, caries was the only included disease condition unfavorably associated with breastfeeding. The present critical review examines the evidence connecting breastfeeding practices to these outcomes and discusses the methodological challenges inherent in reaching causal conclusions. Published systematic reviews show some evidence of a protective effect of breastfeeding against primary dentition malocclusion but no supportive evidence for mixed dentition and permanent dentition malocclusions. Regarding caries, well-conducted studies report a benefit with breastfeeding up to 12 mo but a positive association between caries and breastfeeding of longer duration, at times that vary between 12 and 24 mo, as well as nocturnal feeding. Future studies would be methodologically stronger if focused on specific malocclusion traits that are plausibly associated with sucking movements rather than using general malocclusion indices. Studies should use detailed and consistent terminology for breastfeeding definition, including frequency, intensity, and timing. Analytical studies should be carried out to distinguish between confounders (e.g., prematurity) and mediators (e.g., use of pacifier). Regarding a link to caries, standard terminology for exposures (e.g., nocturnal feeding) is recommended. Statistical analyses must account for known confounding factors (e.g., socioeconomic conditions) but avoid inappropriate adjustment for variables on a causal path between exposure and outcome or for variables not associated with breastfeeding (e.g., tooth brushing), as can be guided using tools such as direct acyclic graphs. For dental practice, the potential caries risk of long-duration breastfeeding should be part of individual patient counseling that incorporates patient values and circumstances. Given the unquestioned overall health benefits of breastfeeding, the dental community should support World Health Organization guidelines that encourage and promote breastfeeding.

OBJECTIVES: The distinct effect of exclusive and predominant breastfeeding on primary dentition malocclusions is still unclear. We hypothesized that exclusive breastfeeding presents a higher protective effect against malocclusions than predominant breastfeeding and that the use of a pacifier modifies the association between breastfeeding and primary dentition malocclusions. METHODS: An oral health study nested in a birth cohort study was conducted at age 5 years (N = 1303). The type of breastfeeding was recorded at birth and at 3, 12, and 24 months of age. Open bite (OB), crossbite, overjet (OJ), and moderate/severe malocclusion (MSM) were assessed. Poisson regression analyses were conducted by controlling for sociodemographic and anthropometric characteristics, sucking habits along the life course, dental caries, and dental treatment. RESULTS: Predominant breastfeeding was associated with a lower prevalence of OB, OJ, and MSM, but pacifier use modified these associations. The same findings were noted between exclusive breastfeeding and OJ and between exclusive breastfeeding and crossbite. A lower prevalence of OB was found among children exposed to exclusive breastfeeding from 3 to 5.9 months (33%) and up to 6 months (44%) of age. Those who were exclusively breastfed from 3 to 5.9 months and up to 6 months of age exhibited 41% and 72% lower prevalence of MSM, respectively, than those who were never breastfed. CONCLUSIONS: A common risk approach, promoting exclusive breastfeeding up to 6 months of age to prevent childhood diseases and disorders, should be an effective population strategy to prevent malocclusion.

Birth cohorts are those among observational studies that provide understanding of the natural history and causality of diseases since early in life. Discussions during an International Association for Dental Research symposium in London, United Kingdom, in 2018, followed by a workshop in Bangkok, Thailand, in 2019, concluded that there are few birth cohort studies that consider oral health and that a broader discussion on similarities and differences among those studies would be valuable. This article aims to 1) bring together available long-term data of oral health birth cohort studies from the low, middle, and high-income countries worldwide and 2) describe similarities and differences among these studies. This work comprises 15 studies from all 5 continents. The most studied dental conditions and exposures are identified; findings are summarized; and methodological differences and similarities among studies are presented. Methodological strengths and weaknesses are also highlighted. Findings are summarized in 1) the negative impact of detrimental socioeconomic status on oral health changes over time, 2) the role of unfavorable patterns of dental visiting on oral health, 3) associations between general and oral health, 4) nutritional and dietary effects on oral health, and 5) intergenerational influences on oral health. Dental caries and dental visiting patterns have been recorded in all studies. Sources of fluoride exposure have been documented in most of the more recent studies. Despite some methodological differences in the way that the exposures and outcomes were measured, some findings are consistent. Predictive models have been used with caries risk tools, periodontitis occurrence, and permanent dentition orthodontic treatment need. The next steps of the group’s work are as follows: 1) establishing a consortium of oral health birth cohort studies, 2) conducting a scoping review, 3) exploring opportunities for pooled data analyses to answer pressing research questions, and 4) promoting and enabling the development of the next generation of oral health researchers.