» Articles » PMID: 39797316

Second Versus First Molar Extractions in Class II Division 1 Malocclusion Treatment: A Retrospective Longitudinal Outcome Study into Maxillary Canine, Premolar, and Molar Movement

Overview
Journal J Clin Med
Date 2025 Jan 11
PMID 39797316
Authors
Affiliations
Soon will be listed here.
Abstract

This retrospective longitudinal outcome study comparing orthodontic extraction modalities, including extraction of maxillary first or second molars, aimed to compare the three-dimensional tooth movement of maxillary canines (C), premolars (P1, P2), and molars (M1, M2) in Class II division 1 malocclusion treatment with fixed appliances. A sample of 98 patients (mean age 13.20 ± 1.46 years) was selected for the M1 group, and 64 patients (mean age 13.20 ± 1.36 years) were chosen for the M2 group. Tooth movement was analyzed three-dimensionally on pre-treatment (T0) and post-treatment (T1) digital dental casts. Regression analyses compared the tooth movements (in mm) between the M1 and M2 groups. The mean treatment duration for the M1 group was 2.51 ± 0.55 year, while, for the M2 group, it was 1.53 ± 0.37 year. The data showed limited distal movements of the C, P1, and P2 of approximately 2 mm in the M1 group and 1 mm in the M2 group during orthodontic treatment, but the M1 group exhibited significantly more distal movements than the M2 group (mean difference 1.11 to 1.24 mm). Vertical movements of the C, P1, and P2 in both groups were also minor (0.16 to 1.26 mm). The differences between groups did not exceed 0.2 mm and were not significant. Both treatment modalities resulted in a significant degree of anchorage loss with a distinct mesialization (8.40 ± 1.66 mm) of M2 in the M1 group and limited distalization (0.83 ± 0.98 mm) of M1 in the M2 group. The findings highlight the importance of thorough case evaluation when choosing between extraction modalities in Class II treatment. If a large distal movement of canines and premolars is required, additional anchorage mechanics should be considered.

References
1.
Evrard A, Tepedino M, Cattaneo P, Cornelis M . Which factors influence orthodontists in their decision to extract? A questionnaire survey. J Clin Exp Dent. 2019; 11(5):e432-e438. PMC: 6599705. DOI: 10.4317/jced.55709. View

2.
Booij J, Kuijpers-Jagtman A, Bronkhorst E, Livas C, Ren Y, Kuijpers M . Class II Division 1 malocclusion treatment with extraction of maxillary first molars: Evaluation of treatment and post-treatment changes by the PAR Index. Orthod Craniofac Res. 2020; 24(1):102-110. PMC: 7891627. DOI: 10.1111/ocr.12412. View

3.
Ganzer N, Feldmann I, Liv P, Bondemark L . A novel method for superimposition and measurements on maxillary digital 3D models-studies on validity and reliability. Eur J Orthod. 2017; 40(1):45-51. DOI: 10.1093/ejo/cjx029. View

4.
Schmitz J, Keilig L, Daratsianos N, Bourauel C . Superimposition of dental models to determine orthodontic tooth movements : Comparison of different superimposition methods in vitro and in vivo. J Orofac Orthop. 2024; . DOI: 10.1007/s00056-024-00513-6. View

5.
Liu J, Koh K, Choi S, Kim J, Cha J . Validation of three-dimensional digital model superimpositions based on palatal structures in patients with maximum anterior tooth retraction following premolar extraction. Korean J Orthod. 2022; 52(4):258-267. PMC: 9314216. DOI: 10.4041/kjod21.126. View