Related Experiment Video
Updated: Jun 23, 2026

Measuring Maxillary Posterior Tooth Movement: A Model Assessment using Palatal and Dental Superimposition
Published on: February 23, 2024
Change of incisor inclination effects on points A and B
Rasha Al-Abdwani1, David R Moles, Joseph Harold Noar
1Department of Orthodontics, UCL Eastman Dental Institute, 256 Gray's Inn Road, London WC1X 8LD, UK. toothfairy999@hotmail.com
Objective:
To identify and evaluate changes in the cephalometric position of points A and B due to an incisal inclination change caused by orthodontic treatment.
Materials And Method:
A total of 103 pairs of consecutive pretreatment and posttreatment lateral cephalographs that met the inclusion criteria were systematically collected from the departmental database and digitized using a customized software program (Gela). Repeatability analyses showed good reliability and no evidence of bias. A statistical model was generated using a Generalized Estimating Equation approach to analyze the data accounting for growth and bodily movement because both factors influence the position of points A and B (P < .001, P < .001). Changes in tooth length were also accounted for, as these changes may influence the calculated position of the centroid (P = .002).
Results:
Each 10 degrees change in the maxillary incisor inclination results in a statistically significant average change in point A of 0.4 mm in the horizontal plane (P = .028). Each 10 degrees change in the mandibular incisor inclination results in a borderline statistically significant average change in point B of 0.3 mm in the horizontal plane (P = .058). There were no significant changes in the vertical position of points A and B.
Conclusion:
The effects of incisal inclination changes, due to orthodontic treatment, are of no clinical relevance to the position of point A and B, even though they may be statistically significant. The validity of points A and B as skeletal landmarks generally holds true, and accounting for treatment changes is unnecessary.
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