POSTTREATMENT CHANGES IN MALE AND FEMALE-PATIENTS - A COMPARATIVE-STUDY

The purpose of this study was to determine whether the posttreatment c hanges in patients with Class II, Division I malocclusions who were tr eated with either extraction or nonextraction express similar trends i n the male and female patients. The material for this investigation wa s obtained from the records available in the Graduate Orthodontic Clin ic at the University of Iowa. Ninety-one patients were treated for the ir Class II, Division 1 malocclusions, 44 subjects (21 males and 23 fe males) had four first premolar extractions and 47 subjects (20 males a nd 27 females) were treated with nonextraction. Matched normal subject s included 20 male and 15 female subjects for whom complete sets of da ta were available for the period of this study. None of these subjects had undergone orthodontic therapy. Thirty-nine cephalometric anteropo sterior and vertical skeletal, dental, and soft tissue linear and angu lar measurements were derived. Twenty-four dental arch parameters were evaluated and included: overbite, overjet, maxillary and mandibular a rch lengths, and arch widths, as well as tooth size-arch length discre pancies. Student t tests were used to compare male and female subjects for the following parameters: (1) absolute dimensions recorded before treatment, after treatment, and at retention; (2) the incremental cha nges between the various stages; (3) the relative posttreatment change s. The level of significance was predetermined at p less than or equal to 0.05. From the current findings the following can be concluded: (1 ) There were significant differences in the size as well as the increm ental changes of the various cephalometric dentofacial parameters betw een normal male and female subjects. (2) There were significant differ ences in the absolute posttreatment cephalometric changes between male and female subjects, particularly in linear dimensions. Similar, but less frequent, findings were observed in the relative post-treatment c hanges. (3) Significant differences in the posttreatment dental arch c hanges between male and female subjects were the least frequent. (4) M ale and female subjects expressed similar statistical trends in the di rection of posttreatment changes. Therefore clinicians should not expe ct to observe significant differences in the posttreatment trends on t he basis of the gender of the patient, On the other hand, the changes in linear dimensions are larger in male than female subjects. Therefor e, for a more accurate interpretation of growth and/or treatment chang es, it is advisable to independently analyze data on male and female s ubjects.