Mandibular advancement analysis among orthodontists, lay people and patients in class II malocclusion subjects. A three-dimensional imaging study.

Abstract

To evaluate the acceptance of orthodontists, laypeople and the patient when progressive mandibular advancements are performed in class II subjects with mandibular retrognathism. 3D images were obtained by an optical surface scanning of fifteen individuals (12 males and three females, mean age of 23years and 8months) with mandibular retrognathism in three mandibular positions: maximum intercuspation (MIC) and progressive mandibular advancement of 2 and 4mm. The images (n=45) were evaluated through a scale by two groups of panellist, 20 orthodontists, 20 laypeople and by the patients themselves (n=15). The participants evaluated and rated each video and give scores between 0 and 10, according to their perception of facial harmony. MANOVA for repeated measures was used for intra- and intergroup differences and to evaluate the patients' self-perception. Laypeople reported better face acceptance than orthodontists in MIC and progressive mandibular advancement of 2 and 4mm (P<.0001). 80% of the patients evaluated their own face as pleasant in MIC. Around half of them did not note significant difference following mandibular advancement of 2mm as compared with MIC and even two-third attributed lower scores when the mandible was advanced 4mm. A high variability was observed among all groups of raters. Patient´s opinion should be taken into account when mandibular advancement of 4mm or more is planned. This study suggests that a thorough discussion of facial changes resulting from mandibular advancement should be carried out among professionals, parents and patients.