Arch widths after extraction and nonextraction treatment in class I patients.

AIM To compare pretreatment and post-treatment dental arches in relation to intercanine and intermolar width changes in extraction and nonextraction treatment in class I patients. MATERIALS AND METHODS In this retrospective study pretreatment and post-treatment dental casts of 60 patients (30 extractions of first premolars and 30 nonextractions) were selected. Anterior and posterior arch widths in the canine and molar regions from the most labial aspect of buccal surfaces, the canines and the molars were measured with the help of digital caliper on the study models and compared statistically to determine whether the dental arches were narrower after extraction treatment. RESULTS At the start of the treatment there were no statistically significant differences in maxillary and mandibular intercanine widths in both groups. At the end of treatment in both the groups anterior and posterior arch width changes were not significant except for the intercanine dimension which was 0.82 mm larger (p < 0.05) in the extraction group. CONCLUSION The extraction treatment does not result in narrower dental arches than nonextraction treatment in intercanine and intermolar region. CLINICAL SIGNIFICANCE It is documented that the arch widths determine smile esthetics and treatment stability. According to the findings of the present study the arch widths in extraction treatments are not narrower than nonextraction so there will not be any compromising effects on esthetics and treatment stability.