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Mandibular alignment changes after full-fixed orthodontic treatment: a systematic review and meta-analysis
Ahmad J Swidi1,2, Andreea E Griffin3, Peter H Buschang1
1Orthodontic Department, College of Dentistry, Texas A&M University, Dallas, TX, USA.
European Journal of Orthodontics
|February 22, 2019
Summary
Mandibular alignment can worsen after orthodontic treatment, especially with premolar extractions and longer follow-up periods. This meta-analysis found limited increases in irregularity, but evidence quality was low.
Area of Science:
- Orthodontics
- Dental Research
Background:
- Mandibular alignment changes post-orthodontic treatment are debated.
- Assessing long-term stability of orthodontic results is crucial.
Purpose of the Study:
- To evaluate changes in mandibular alignment using the irregularity index after full-fixed orthodontic treatment.
- To analyze post-retention follow-up data of at least one year.
Main Methods:
- Systematic review and meta-analysis of published studies.
- Searched MEDLINE, EMBASE, and Cochrane Library up to April 2018.
- Included interventional and observational studies; assessed quality using established tools.
Main Results:
- Included 44 studies (1 RCT, 43 observational) with 1859 patients in meta-analyses.
- Post-retention irregularity increase was 1.22 for extraction and 0.85 for non-extraction cases.
- Longer follow-up durations (10-20 years) showed significantly more irregularity.
Conclusions:
- Evidence quality is low, with potential publication bias.
- Limited increases in post-treatment mandibular irregularity occur.
- Slightly greater increases are noted in extraction cases and with longer follow-up.
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