Changes during treatment of class III malocclusion by Y appliance and appliance with screw according to Bertoni

Abstract

Introduction/Objective. Class III malocclusion is caused by changes in skeletal and/or dentoalveolar structures with typical mesial relationship of posterior teeth. Y? appliance and appliance with screw according to Bertoni can be used in treatment of Class III caused by maxillary retrognathism in period of mixed dentition. The aim of study was to determine and compare changes on skeletal and dentoalveolar structures in patients with Class III treated by ?Y? appliance and appliance with screw according to Bertoni. Methods. 40 patients with Class III were included in this study. Whole sample were divided in two groups, with 20 patients in each group. Including criteria were maxilarry retrognatism, period of mixed dentition and pubertal growth. Excluding criteria were mandibular prognatism, patients with genetical predisposition for skeletal Class III, patients with cleft lip and palate or craniofacial syndrome and period of permanent dentition. Appliances which caused mostly changes on the upper jaw were used in this study because all patients had deficience of maxillary growth. Anamnesis, clinical and functional testing, study casts analysis, analysis of orthopantomograms, lateral cephalograms, extraoral and intraoral photos have been done for each patient. Therapeutic effects were analysed on study casts and lateral cephalograms after this phase of orthodontic treatment. Results. Main dentoalveolar effect was protrusion of the upper incisors. Skeletal effects were not significant. Conclusion. Y appliance and appliance with screw according to Bertoni caused greater changes on dentoalveolar structures comparing to skeletal changes.