Prevention of external apical root resorption during orthodontic treatment

The issue of orthodontic-induced external apical root resorption (EARR) has attracted the interest of clinicians and investigators because of the alarming clinical and legal implications associated with its occurrence in a severe form. The January/February 2005 issue of the American Association of Orthodontist’s Bulletin reported that medical malpractice is a significant problem in the USA today and that patients are filing claims and lawsuits against medical and dental practitioners, including orthodontists, in record numbers. EARR is a common iatrogenic consequence of orthodontic treatment. Cross-sectional as well as longitudinal studies show that EARR is a small problem for the average orthodontic patient, with radiographic mean resorption of less than 2.5 mm. This magnitude of resorption has no adverse clinical consequences. However, 1–5% of orthodontic patients experience a severe form of EARR, defined as exceeding 4 mm or one-third of the original root length. Severe root resorption mainly occurs in maxillary incisors. It compromises crown–root ratios and can result in tooth mobility. The main etiologic risk factor for the severe form of EARR is genetic predisposition. Emphasis is thus given on the root-sparing treatment procedures to minimize the risk for development of the severe form of EARR. Orthodontists are highly trained dental caregivers obligated to abide by the Hippocratic Oath of doing no harm. It is the author’s hope that this article will create awareness among clinicians that there are orthodontic and orthopedic treatment regimes designed precisely to minimize or even avoid the development of EARR. Successful treatment should begin at a young age so that the clinician can take advantage of eruption guidance and of growth modification when a Class II skeletal problem exists. Suggested treatment regimes outlined in this paper minimize the distance that teeth/root apices need to be moved.