To Evaluate the Total Tooth Length of the MandibularAnteriors Treated by Extraction of all 4first Premolar in Class I Bimaxillary Protrusion Cases Using CBCT - A Comparative

Aim: To evaluate the changes in the total tooth length during lower incisor retraction in Bimaxillary protrusion cases (Class I)using Cone Beam Computed tomographic images. Methodology: Ten patients undergoing orthodontic treatment with MBT 3M (Abzil) - 0.022 slot appliance were selected. Change in periapical region was measured by comparing the pre-treatment and post-retraction CBCT of the Mandibular anterior region. ONDEMAND Software was used for image processing and analysis to evaluate the changes in the Total Tooth Length [TTL] during lower incisor retraction in class I Bimaxillary protrusion cases. Result: Total tooth length was reduced compared to the pretreatment CBCT images. The mean Total tooth length [TTL] Pretreatment [T0] was 18.38 mm and Post-treatment [T1] was 17.38 mm; the difference value of mean Total Tooth Length [TTL] was 1.0 mm (p value = 0.02). Conclusion: The study showed that there was a decrease in the total tooth length [TTL].