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Three-dimensional measurement of tooth inclination: A longitudinal study
Mahtab Nouri1, Sahar Khaje Hosseini2, Sohrab Asefi3
1Department of Orthodontic, Dentofacial Deformities Research Center, School of Dentistry, Research Institute of Dental Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Dental Research Journal
|July 16, 2019
Summary
Tooth inclination changes over time in adolescents with normal occlusion were measured using 3D software. Sex significantly impacted these changes, with considerable variation observed in tooth torque.
Area of Science:
- Dentistry
- Orthodontics
- Biomedical Engineering
Background:
- Advancements in 3D imaging tools enable precise tooth inclination measurement.
- Assessing longitudinal changes in tooth inclination is crucial for orthodontic treatment planning.
Purpose of the Study:
- To quantify tooth inclination changes over 2 and 4 years in adolescents with normal occlusion.
- To analyze the influence of sex, follow-up duration, and jaw on tooth inclination changes.
Main Methods:
- Retrospective longitudinal study of 24 adolescents (9-13 years) with normal occlusion.
- Three-dimensional (3D) measurements of tooth inclination using OrthoAid software.
- Statistical analysis using Mann-Whitney and Wilcoxon tests (P < 0.05 significance).
Main Results:
- Positive incisor torque observed in both maxilla and mandible.
- Negative torque noted for canine, premolar, and molar teeth in both jaws.
- Maxillary lateral incisor in boys showed the greatest inclination change (~7°); mandibular canine in girls showed the least (4°).
Conclusions:
- Sex significantly influences tooth inclination changes during the study period.
- Significant variation in torque changes was observed.
- No consistent pattern of inclination change was identified across all teeth and sexes.
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