Trends in surgical-orthodontic management of Class III malocclusions in Western Australia

Aim: The aim of this retrospective cohort study was to identify trends in the surgical-orthodontic management of skeletal Class III malocclusions in Western Australia between 1985 and 2016. Methods: The records of 225 patients (132 females, 93 males) who received combined surgical-orthodontic correction of their Class III malocclusion between 1985 and 2016 were retrospectively assessed. The subjects were divided into three groups according to surgery type: Group (1) maxillary advancement only; Group (2) mandibular setback only; Group (3) two-jaw surgery. Results: A trend towards two-jaw surgery for Class III correction was observed. Between 1985 and 2016, 123 patients (55%) were treated via two-jaw surgery; 97 patients (43%) were treated via maxillary advancement alone and five patients (2%) were treated via mandibular setback alone. Between 2011 and 2016, 61% were treated via two-jaw surgery; 37% were treated via maxillary advancement surgery; 2% were treated via mandibular setback surgery. Gender affected surgery type: two-jaw surgery (60% female); maxillary advancement (62% female); mandibular setback (17% female). A greater proportion of females received Class III surgical management in comparison with males (59:41). Conclusion: Two-jaw surgery is the most common procedure for the surgical correction of skeletal Class III malocclusions in Western Australia. Of the single jaw procedures, isolated maxillary advancement surgery is more common than mandibular setback procedures.