An evaluation of factors affecting duration of orthodontic treatment

One of the first questions asked by new orthodontic patients is: How long w ill I need to wear my braces? A multitude of factors have the potential to influence the answer to this question. The purpose of this retrospective st udy was to identify some of the primary factors that influence orthodontic treatment duration. Few studies have attempted to evaluate these factors. D ata were gathered from 140 consecutively completed, comprehensive treatment patient records in five orthodontic offices. Thirty-one variables related to patient characteristics, diagnostic factors, modality of treatment, and patient cooperation were evaluated. Average treatment time was 28.6 months with a range of 23.4 to 33.4 months among the five offices. Nearly half (46 .9%) of the variation in treatment duration was explained by a five-step mu ltiple regression analysis. Included in the regression equation were the nu mber of missed appointments, the number of replaced brackets and bands, the number of treatment phases, the number of negative chart entries regarding oral hygiene, and the prescription of headgear wear during treatment. An a dditional 6.7% of the variance was explained by variation among the five of fices. Six of the 31 variables examined made a statistically significant (a lpha = .01) contribution to the explanation of variation in treatment time. The quality of the finished cases and the appropriateness of the original diagnosis and treatment plan were not evaluated. Developing an objective as sessment to evaluate these areas may be important for increasing our unders tanding of treatment time variation.