Purpose: The purpose of this study was to determine if dental ages are more advanced in overweight children and influenced by genetic variation. Methods: Panoramic radiographs from 577 children were obtained. For performing genetic studies, an additional 236 subjects had panoramic radiographs and whole saliva samples collected. Genotyping of IGF, FGF, and FGFR markers was done. Dental age was determined in 177 patients utilizing Demerjian's method and panoramic radiographs. Skeletal maturation was determined in 28 patients using Baccetti's cervical vertebral maturation method on lateral cephalograms. PLINK was used to test for over-representation of alleles. Results: FGF7, FGF10, and FGF13 were significantly associated with obesity (P = 0.02). When dental age was considered, overweight and obese children are more likely to have dental ages more advanced than their chronological ages (P = 0.05). An excess of heterozygotes of FGF18 rs4073716 was found in children with dental age more advanced than their chronological age (P=0.04). Conclusions: Overweight and obese children have dental ages more advanced than their chronological ages, and this occurrence may be influenced by genetic variation in FGF18.