Download Influence of the apical root morphology in the potential external root

Influence of the apical root morphology in the potential external root
resorption related to orthodontic treatment.
Introduction: This prospective study aimed to verify whether the shape of the
apical root affected the severity of root resorption during fixed orthodontic
treatment. Methods: Pre- and post-treatment panoramic radiographs of 100
patients, 50 males and 50 females, were evaluated. Patients were included
according to the following criteria: no history of previous orthodontic treatment,
presence of all permanent teeth, and current orthodontic treatment carried out
by a single group of clinicians using the Roth-Slot .022 technique. Blinded
images were randomly assessed by three calibrated observers. The apical root
shape was assessed as described by Levander & Malmgren (1988) and the
long axis of the upper incisors was measured using an accurate caliper. Data
were analyzed by one-way ANOVA, the paired student’s t-test, and the
Wilcoxon test for paired samples. Results: There was no statistical significant
difference (p > 0.05) among the three observers concerning the initial and final
lengths (mm), and the length variation (%). The incisor length decreased
significantly from pre- to post-treatment (p < 0.05) for each observer, indicating
external resorption of the apical root. Conclusion: Moderate apical root
resorption occurred after orthodontic treatment, and pipette and triangular root
shapes showed the greatest root resorption.
Keywords: Root resorption; Orthodontic movement; Root morphology