Mesiodistal tip and faciolingual torque outcomes in computer-driven orthodontic appliances

Abstract

BackgroundTo investigate the accuracy of the three-dimensional clinical outcome of root inclination (faciolingual torque) and angulation (mesiodistal tip) of SureSmileTM (SS)-treated cases. MethodsInitial SS cone-beam computed tomography (CBCT), SS initial model, SS target model (plan or simulation), and post-treatment CBCT (outcome or final CBCT) results were collected for consecutively 30 finished SS cases. Discrepancies between these variables were compared against the mean discrepancies of the initial CBCT and the initial model for 10 randomly selected cases, which represented a baseline for expected mean discrepancy of like samples. One-sample t-tests were conducted to assess if there was a difference between the planned tooth tip and torque and their treatment outcomes. The t-tests were further used to assess these discrepancies by the individual tooth type. ResultsThe results indicate statistically significant differences between the target and clinically achieved outcomes for both the tooth tip and torque overall across a majority of tooth types. ConclusionAlthough statistically different, the overall mean discrepancy of the SStarget models to the outcome CBCT were within the clinically acceptable range (±2.5°). The mean outcome discrepancies were found to be statistically significant across several tooth types, but their clinical significance (beyond ±2.5°) was limited to the maxillary and mandibular second molars for tip and the maxillary second molar and mandibular central and lateral incisors for torque. Overall, the tip outcomes were closer to the plan than the torque outcomes for most of the tooth types.