Preplanning Contemporary Incisor Positioning using Inclinometer: A Clinical and Cephalometric Study

Abstract

Introduction: The purpose of the present study is to link the fields of cephalometric assessment of incisor inclination with that of contemporary orthodontic incisor inclination correc tion, in order to enhance the applicability of well-accepted cephalometric standards. Materials and methods: The sample of the study consists of 120 subjects, 53 males and 67 females pretreatment lateral cephalograms and corresponding dental casts with proper inclusion criteria. Upper (U1) and lower (L1) axial incisor inclinations were assessed using inclinometer with reference to the cephalometric lines NA (nasion to point A) and NL (palatal plane), and NB (nasion to point B) and ML (mandibular plane: tangent to the lower border of the mandible) respectively. Sagittal and vertical skeletal relationships were classified using SNA (SNB) and NSL (SN plane)—ML (NSL-NL) angles. Third order angles [U1TA (upper incisor torque angle) and L1TA (lower incisor torque angle)] were derived from direct dental cast measurements using an incisor inclination-recording appliance (inclinometer). Results: Cephalometric assessments of upper incisor inclination showed a range of 31 ± 5.27° for U1NA/degree and 32 ± 5.84° for the U1NL. Lower incisor inclination showed a variation of 28.5 ± 6.58 (L1NB/degree) and 36.75 ± 7.2 to the L1ML respectively. Third-order angles varied between 31° for U1TA and 35° for L1TA. In the upper arch, U1TA assessments underscored U1NA/degree values with a mean of 14.43° and U1NL data at a mean of 104.63°. Conclusion: Third-order measurements using inclinometer device can offer a simple way to get an objective and rapid vision of the incisors inclination and might be a helpful guideline to the choice of low or high torque brackets. Incisor inclination is strongly correlated with skeletal-sagittal data, but little with skeletal-vertical findings. OrIgInal reSearch