INTRODUCTION: Costello Syndrome (CS) is a rare, autosomal dominant genetic disorder caused by mutations in the HRAS gene. Its systemic and orofacial manifestations are highly relevant to pediatric dentistry. This study reports the case of a Brazilian female child who began receiving dental care at 25 months of age at the Children's Specialties Clinic, located at the Baby Clinic of the State University of Londrina, with dental follow-up over five years. CASE REPORT: The patient presented systemic alterations (pulmonary valve stenosis, laryngomalacia, growth and developmental delay, among others), facial features (macrocephaly, hypertelorism, broad nasal base, wide mouth), and oral conditions (anterior open bite, posterior crossbite, enamel hypoplasia, diastemas, tooth gemination, bruxism, and oral hypersensitivity). The pediatric dental approach focused on individualized preventive strategies, including dental biofilm control, oral hygiene guidance for caregivers, dietary counseling, and topical application of silver diamine fluoride. At six years old, orthopedic treatment with the SN3 appliance was proposed, but adherence was low due to sensory issues. RESULTS: Over a 5-year follow-up period, there was progressive improvement in clinical behavior, oral hygiene, and adoption of healthier habits. CONCLUSION: The manifestations of CS are diverse and affect multiple tissues, with significant systemic, facial, and oral alterations. Early multidisciplinary follow-up is essential for timely diagnosis and therapeutic planning, with an emphasis on oral health promotion, functional rehabilitation of the stomatognathic system, and aesthetic interventions aimed at improving the child's quality of life and that of their family.
Fagundes et al. (2026) studied this question.