Association between Smoking during Pregnancy and Short Root Anomaly in Offspring

Short root anomaly (SRA) is a dental anomaly with short dental roots and its pathogenesis is poorly understood. This study investigated the association between maternal smoking during pregnancy and SRA in offspring. A survey was conducted on 558 children aged 8-16 years from two public schools in Ulaanbaatar, Mongolia. SRA was diagnosed using cases with a root-crown ratio of maxillary central incisors of ≤1.0. A questionnaire survey was conducted to assess maternal lifestyle habits. Multiple logistic regression was used to analyse the association between maternal smoking during pregnancy and SRA in offspring after adjusting for possible confounders. The prevalence of SRA in these children was 14.2%. Children whose mothers smoked from pregnancy to date were found to be 4.95 times (95% confidence interval [CI]: 1.65-14.79) more likely to have SRA than those whose mothers never smoked, after adjusting for possible confounders. Additionally, children whose mothers had been exposed to passive smoking during pregnancy were found to be 1.86 times (95% CI: 1.02-3.40) more likely to have SRA than those whose mothers had not been exposed to passive smoke. Our population-based study suggests that maternal and passive smoking exposure during pregnancy can affect tooth root formation in children.