comparison of dental arch symmetry in orthodontic patients treated with and without permanent tooth extraction using extraoral scanners

Abstract

Background and aims: Many orthodontic treatments require tooth extraction to create sufficient space for tooth alignment, but concerns persist about the effect of this procedure on dental arch symmetry. This study aimed to compare arch symmetry between extraction and non-extraction treatment plans using extra oral scanners. Methods and Materials: This cross-sectional study was conducted on orthodontic casts of patients treated in the post graduate orthodontic department, dentistry faculty of Tabriz University of medical sciences. A total of 60 casts were selected, including 30 casts, in which the treatment involved tooth extraction and had their first premolars extracted, and another 30 casts, in which the treatment did not involve tooth extraction. After selecting the casts, they were scanned using the rainbow scanner (Dentium, South Korea). Digital data were analyzed using Exocad and Meshmixer and Photoshop software to compute transverse and anteroposterior arch symmetry indices. The obtained data were compared using statistical tests to compare arch symmetry between extraction and non-extraction groups. Results:The results of data analysis indicated that in both canine and molar areas, there were no significant differences in transverse and anteroposterior symmetry between the extraction and non-extraction groups. Furthermore, inter-examiner and intra-examiner error mearurments showed that there was no noticeable error while measuring data. Conclusion: Extraction in orthodontic treatments, when performed correctly, does not significantly impact on dental arch symmetry. Also the use of extra oral scanners may be beneficial for more accurate measurements in orthodontists. Keywords: Orthodontics, Dental Arch Symmetry, Tooth Extraction, Digital Dentistry, Dental Models.