Korean J Orthod.  2011 Jun;41(3):174-183. 10.4041/kjod.2011.41.3.174.

Factors affecting orthodontically induced root resorption of maxillary central incisors in the Korean population

• Chung DH
• Park YG
• Kim KW
• Cha KS

• KMID: 1975429
• DOI: http://doi.org/10.4041/kjod.2011.41.3.174

Abstract

OBJECTIVE
Orthodontically induced root resorption (OIRR) involves partial loss of cementum and dentin of teeth caused by routine orthodontic treatment. It decreases root length and influences the function of affected teeth. In this study, the treatment and patient factors causing apical root resorption in Koreans were determined. The observed factors were extraction, gender, age, displacement of root apex, total treatment period, total teeth length, and shape of the root.
METHODS
The records of 137 patients treated with full, fixed edgewise appliances were obtained from the Department of Orthodontics, Dankook University Dental Hospital, from November 2007 to December 2008. Periapical radiographs of the maxillary central incisors and cephalometric radiographs of each patient were used to assess apical root resorption and type of tooth movement.
RESULTS
The mean amount of resorption was 1.62 +/- 1.58 mm. The amount of resorption in the extraction and non-extraction groups was 2.10 +/- 1.64 mm and 1.18 +/- 1.39 mm, respectively. The amount of root resorption increased with the total tooth length. Severe root resorption (> 4 mm) was related to abnormal root shape (blunt, pointed, or eroded).
CONCLUSIONS
The variables significantly related to OIRR were extraction, initial tooth length, and root shape.

Keyword

Root resorption; Extraction; Root shape

MeSH Terms

Dental Cementum
Dentin
Displacement (Psychology)
Humans
Incisor
Orthodontics
Root Resorption
Tooth