Introducción: Diabetes mellitus is a group of metabolic diseases characterized by chronic hyperglycemia resulting from defects in insulin secretion, insulin action, or both. There is a significant relationship between type 1 diabetes mellitus (T1DM) and an increased prevalence of oral cavity-related diseases in the pediatric population.

Objective: To analyze the literature and describe T1DM and its oral manifestations, including alterations in saliva and dentobacterial plaque, as well as periodontal disease and caries, and to emphasize its importance in pediatric dentistry.

Methodology: An exhaustive search was carried out in PubMed with the keywords Type I diabetes Mellitus, children, oral manifestations, caries, periodontal disease, gingivitis, xerostomia, pediatric dentistry, candida.

Results: Salivary flow could be considered decreased with T1DM. Higher plaque levels and higher incidence of chronic gingivitis. Higher risk of developing periodontal disease. Higher caries levels, higher prevalence of xerostomia. Insulin treatment may cause local reactions such as lipohypertrophy, lipoatrophy and instant and delayed allergy. Erythema multiforme, leukocytoclastic vasculitis, drug eruptions and photosensitivity have been described as adverse reactions to oral antidiabetics.

Conclusion: Childhood and adolescent patients with T1DM have a predisposition to xerostomia and this leads to halitosis and a favorable environment for the proliferation of bacteria and the formation of dental caries, they present greater accumulation of plaque and therefore are susceptible to gingival inflammation and this ends in periodontal disease at an early age producing bone loss. Patients receiving insulin often present skin lesions. Medications can immunosuppress and this makes them susceptible to Candida.