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Apical root resorption in patients treated with comprehensive orthodontics
E F Harris1, B W Boggan, D A Wheeler
1College of Dentistry, University of Tennessee, Memphis, USA.
The Journal of the Tennessee Dental Association
|April 28, 2001
Summary
Most orthodontic patients experience slight external apical root resorption (EARR), especially in incisors. Genetic susceptibility appears to be the primary driver, not treatment specifics.
Area of Science:
- Dentistry
- Orthodontics
- Genetics
Background:
- External apical root resorption (EARR) is a frequent outcome of orthodontic therapy.
- Incisors are particularly susceptible due to their morphology and typical treatment movements.
Purpose of the Study:
- To investigate the prevalence and contributing factors of EARR in patients undergoing comprehensive orthodontic treatment.
- To identify key predictors of EARR severity.
Main Methods:
- A cohort of 153 patients undergoing orthodontic treatment was studied.
- Upper incisor EARR was assessed using a five-grade ordinal scale.
- Data on patient sex, age, malocclusion severity, treatment mechanics, and premolar extractions were collected.
Main Results:
- Over 80% of patients showed slight-to-moderate EARR (1-2 mm loss) by treatment end.
- Premolar extractions correlated with increased EARR, likely due to greater incisor retraction.
- Patient sex, age, malocclusion severity, and mechanics explained minimal EARR variation.
Conclusions:
- Inter-individual variation in genetic susceptibility is the most significant factor influencing EARR.
- Further research into the biochemical basis of EARR susceptibility is warranted.
- Screening patients for genetic predisposition could help identify those at higher risk.
