Objective: The aim of this research is to study the behavior of mandibular asymmetries in skeletal Class III (CIII) patients.

Patients and methods: Out of 280 skeletal CIII patients treated between 2005 and 2010 in this program a random sample of 142 patients, 91 women and 41 men was analyzed. Age: 18.5 years DS ± 4.2. A frontal and posteroanterior teleradiography and clinical analysis is performed, using a cephalogram developed by the authors, and a custom analysis of the orthopantogram; to determine the asymmetries prevalence, its correlation with the affected mandibular structures, the presence of compensations, and the associations with the inclination of the maxilla. Statistically, the Test Z’ for 2 proportion, exact Fisher’s, Chi-Square was used.

Results: The observed prevalence of asymmetries in CIII patients was 65.5%; women (69%) men (59%), not showing statistical significance. The left asymmetry (51.6%) and the right (48.4%) did not show statistical significance either. The condyle (44%) and the ramus (19%), are the most affected structures in the etiology of the asymmetry, being the affected side statistically irrelevant. 71% of the asymmetric patients showed compensation. 43% of these patients also showed maxillary inclination.

Conclusions: A prevalence of 65% asymmetry in skeletal CIII is shown. The patient’s gender and the side of the affected mandible do not influence the expression of the asymmetry. The affected mandibular structure is independent from the side affected, showing frequently compensation in ipsilateral and contralateral structures. The maxillary inclination can be present independently from the side of the asymmetry.

Conflict of interest: None declared.