Factors Affecting the Duration of Fixed Orthodontic Treatment in Patients Treated in a University Department between 2016 and 2020.

The aim of this study was to assess the effect of possible influential factors on duration of fixed orthodontic treatment. This cross-sectional retrospective study included 505 female and 183 male orthodontic patients (a total of 688 persons) referring to a university department of orthodontics during 2016-2020. The study population included only those who had undergone fixed orthodontic treatment of both maxillary and mandibular arches. Information including age, gender, total treatment duration, number of missed treatment sessions, incidences of bracket debonding, and type of treatment plan were collected from patient records. Data were analyzed using SPSS software version 21 at 0.05 significance level. The mean duration of orthodontic treatment was significantly longer in men than women (19.09±5.6 18.22±4.56 months, respectively; P=0.040). The treatment duration was also longer in patients with a treatment plan including teeth extraction compared to non-extraction treatment plans (19.85±4.30 17.56±5.02 months, respectively; P<0.001). Duration of treatment in patients with more than one missed treatment appointment was significantly longer than those who had . one missed session (P<0.001). Duration of treatment in patients with bracket debonding was significantly longer (P=0.030). Also, the duration of treatment had a significant correlation with the frequency of both missed sessions (r=0.365, P<0.001) and bracket debonding (r=0.098, P=0.01). Based on the results of the present study, missed sessions, treatment plan, and bracket debonding have the greatest effect on the duration of fixed orthodontic treatment.