Recurrent exposure to gastric acid as in children with bulimia and gastroesophageal reflux disease (GERD) may contribute to dental erosion. We performed a prospective study to evaluate the presence of GERD and dental erosions in children with primary and permanent dentition. Children undergoing elective endoscopy for possible GERD (n = 37) underwent evaluation of their teeth for the presence, severity, and pattern of erosion and stage of dentition: 24 patients had GERD. Dental erosions were identified in 20; all had GERD. Erosion patterns showed more involvement of the posterior teeth. Many affected patients had primary dentition.