Incisors inclination in relation to lip parameters: a CBCT study

Abstract

ABSTRACT Introduction: With the introduction of Cone Beam Computed Tomography (CBCT) in dentistry, precise measurements are now attainable. Objective: This study seeks to explore the correlation between incisors inclination and various lip parameters utilizing CBCT technology. Moreover, it aims to assess whether specific incisors inclinations significantly influence lip thickness, length, and position. Material and Methods: This was a retrospective observational study of available records of orthodontic patients (n=84) aged between 11 and 17.5 years old with pre- and post-treatment CBCT imaging. The 3D Slicer software was used to assess lip parameters and incisors inclinations while adhering to standard CBCT imaging methods. Statistical analysis was conducted to find associations between incisors inclination and lip parameters. Results: Within certain limits of incisor inclination, lip parameters showed minimal impact. Changes in upper incisor inclination within an average of 5° did not significantly correlate with upper lip parameters. Similarly, changes in lower incisor inclination within an average of 5.6° had no significant effect on lower lip parameters. However, inclination changes of tooth #21 within 5.4° significantly affected upper lip length within 0.35mm. Conclusions: Lip parameters remained unaffected with specific ranges of incisor inclinations, except for a slight effect on upper lip length with changes in inclination of tooth #21. Clinicians can consider the specific ranges of incisors inclination during treatment planning, especially for patients concerned about lip appearance.

Keywords

• Cone beam computed tomography
• Incisor inclination
• Lip protrusion
• Lip length
• Lip thickness