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Three-Dimensional Comparative Analysis of Root Parallelism in First Premolar Extraction Cases: Clear Aligner Versus
Waseem S Al-Gumaei1,2, Fan Jian1, Xiaoqi Zhang1
1State Key Laboratory of Oral Diseases and National Clinical Research Centre for Oral Diseases and Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China.
Orthodontics & Craniofacial Research
|November 27, 2024
Summary
Invisalign clear aligners show comparable or superior three-dimensional root parallelism to fixed appliances in premolar extraction cases. However, fixed appliances are more effective for mesiodistal incisor root parallelism.
Area of Science:
- Orthodontics and Dental Imaging
- Biomaterials and Biomechanics
Background:
- Orthodontic treatment planning increasingly utilizes advanced imaging like cone-beam computed tomography (CBCT) to assess three-dimensional root positioning.
- Comparing the efficacy of clear aligners (CA) versus traditional fixed appliances (FA) in achieving optimal root parallelism is crucial for treatment outcomes, especially in extraction cases.
Purpose of the Study:
- To quantitatively compare the three-dimensional root parallelism (mesiodistal and buccolingual) between Invisalign clear aligners (CA) and fixed appliances (FA).
- To evaluate treatment outcomes in patients undergoing first premolar extraction with either CA or FA, focusing on root alignment using CBCT.
Main Methods:
- Sixty participants with similar orthodontic discrepancy index scores were divided into CA and FA groups (30 each).
- Post-treatment CBCT scans were analyzed using Invivo 6.0.3 software to measure mesiodistal and buccolingual root parallelisms.
- Statistical analysis was performed with a significance level of p < 0.05.
Main Results:
- Mesiodistal root parallelism was significantly inferior in the CA group for upper (U1-U2) and lower (L1-L2) incisor pairings (p < 0.05).
- Superior mesiodistal parallelism was observed in the CA group for U3-U5 and L5-L6 pairings (p < 0.05).
- Buccolingual root parallelism was significantly superior in the CA group for U5-U6 and L5-L6 pairings (p < 0.05), with no significant differences in other pairings.
Conclusions:
- Invisalign clear aligners can achieve comparable or superior three-dimensional root parallelism to fixed appliances in first premolar extraction cases.
- Fixed appliances demonstrated better mesiodistal root parallelism for incisors, while clear aligners showed advantages in specific posterior tooth pairings.
- CBCT analysis provides valuable insights into the nuanced differences in root control between clear aligners and fixed appliances.
