Objective: To assess whether individuals born with nonsyndromic oral clefts display a higher frequency of dental anomalies.
Design: A search of MEDLINE, BIREME, OVID ALL EMB Reviews, and The Cochrane Library was conducted. The methodologic quality of the papers selected was assessed and scored. Papers reporting observational controlled studies of nonsyndromic forms of oral cleft matched for dental anomalies in primary and/or permanent teeth were included without language restrictions. Eligible studies were scored as "A"-low risk of bias, "B"-moderate risk of bias, or "C"-high risk of bias and poor quality. Fixed and random effects models were used to aggregate individual odds ratios (OR) and to derive pooled estimates and 95% confidence intervals.
Results: Six studies fulfilled our selection criteria and were included in the meta-analysis. Three distinct subgroup analyses were carried out in terms of dental anomalies. In the tooth agenesis meta-analysis, a random effects model was used because of heterogeneity and showed a significant association between tooth agenesis and oral clefts (OR = 12.31; 95% confidence interval [CI] = 3.75 to 40.36). In the remaining analyses, the fixed effects model revealed a positive association between supernumerary (OR = 4.99; 95% CI, 2.58 to 9.64) and crown morphologic abnormalities (OR = 5.69; 95% CI, 3.96 to 8.19) with oral clefts. Most included studies were of low to moderate quality.
Conclusion: Although general limitations in study design were observed, the evidence suggests that a higher number of dental anomalies in the permanent dentition are noted in individuals born with oral clefts.