Orthodontic preparation for orthognathic surgery: how long does it take and why? A retrospective study.

We investigated the duration of pre-operative orthodontic treatment of patients who had combined orthodontic and orthognathic treatment and examined the variables that influenced this. Records of patients who had undergone such treatment in the past 5 years were collected (n=65) from three consultant orthodontists and one Senior Specialist Registrar/Fixed Term Training Appointment (FTTA). The number of days from placement of the first active orthodontic component to the day that final planning impressions were taken was used to calculate the duration of treatment before the patient was ready for operation. The variables investigated were: sex, age, malocclusion, extractions (excluding third molars), and the clinician. The median duration of pre-operative treatment was 17 months (range 7-47). Only the orthodontist appeared to affect this duration, but this requires further investigation as it may merely reflect variation in other factors such as compliance. We conclude that patients should be informed that the pre-operative phase may last 12-24 months.