Meta analysis of the treatment-related factors of external apical root resorption.
OBJECTIVE
To elucidate possible treatment-related etiological factors--such as, duration of treatment and apical displacement--for external root resorption.


METHODS
Meta-analysis of the available English-language literature.


METHODS
Papers with a sample size > 10, fixed appliances, pre- and post-operative radiographs, and apical displacement recorded were included. History of trauma, prior root resorption and endodontic treatment were excluded. Appropriateness of these selections was tested with a 'funnel plot' analysis.


METHODS
Correlations between root resorption, apical displacement, and treatment duration.


RESULTS
Mean apical root resorption was strongly correlated with total apical displacement (r = 0.822) and treatment duration (r = 0.852).


CONCLUSIONS
The treatment-related causes of root resorption appear to be the total distance the apex had moved and the time it took.
Segal
G R
GR
Department of Orthodontics, Temple University, Philadelphia, PA, USA. sgrsegal@aol.com
Schiffman
P H
PH
Tuncay
O C
OC
D003799:Dental Stress Analysis; D006801:Humans; D007180:Incisor; D008437:Maxilla; D012391:Root Resorption / Q000209:etiology*; D013997:Time Factors; D014087:Tooth Movement Techniques / Q000009:adverse effects*