Meta analysis of the treatment-related factors of external apical root resorption

Abstract

Objective: To elucidate possible treatment-related etiological factors--such as, duration of treatment and apical displacement--for external root resorption.

Design: Meta-analysis of the available English-language literature.

Inclusion & exclusion criteria: 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.

Outcome measure: 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).

Conclusion: The treatment-related causes of root resorption appear to be the total distance the apex had moved and the time it took.