Skeletal Class III malocclusion with unconventional extraction. Case report

Abstract

Introduction: Skeletal class III malocclusion occurs due to maxillary deficiency, mandibular excess; or both. The negative discrepancy consists of the disproportion of tooth size and amount of available space. Treatment alternatives are presented including orthopedic, orthodontic forces and extractions. Objective: to describe the evolution of treatment combining maxillary orthopedics and non-conventional extractions in a patient with skeletal class III. Case report: 9-year-old male patient from the Central University of Venezuela attends for aesthetic reasons. Through clinical and cephalometric evaluation, skeletal Class III malocclusion with severe negative discrepancy was diagnosed. It was treated with a McNamara expander and protraction mask, achieving transverse expansion and uncrossing the bite. Guided extractions of primary teeth were performed. In re-evaluation, a cone beam tomography was indicated, showing permanent upper lateral incisor with root resorption caused by an impacted canine; Therefore, the planning of serial extractions was unconventional, including the lower first premolars and lateral incisor. Patient remains in control with eruption guidance and arch shaping. Class I molar and canine occlusion was achieved in the left quadrants and premolar function as a canine in the upper right quadrant. Conclusions: Early therapy combined with orthodontic, orthopedic forces and serial extractions gave favorable results.