Related Experiment Video
Updated: Jul 17, 2026
A Finite Element Approach for Locating the Center of Resistance of Maxillary Teeth
Published on: April 8, 2020
Orthodontically induced root resorption in endodontically treated and vital teeth: a cone beam computer tomographic
Ziang Liu1,2,3, Yuqing Ouyang1,2,3, Yiting Lou1,2,3
1Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Hangzhou, China.
Background:
Orthodontically induced root resorption (OIRR) is a common side effect of orthodontic treatment. This study compares the degree of OIRR between root-filled teeth (RFT) and vital pulp teeth (VPT), and analyzes relevant study variables.
Methods:
We conducted a retrospective study on 69 patients who had undergone orthodontic treatment. Using Cone-beam computed tomography (CBCT), we measured changes of root length before and after treatment through a unique method involving three-dimensional (3D) image registration and superimposition. Factors related to the OIRR such as gender, type of treatment, tooth type, age, duration of treatment and distance of root movement were considered.
Results:
The sample included 55 females and 14 males aged 27.19 ± 6.08 years. On the basis that there was no significant difference in the root movement distance between RFT and VPT, RFT showed significantly less OIRR than VPT (P < 0.05). Gender did not significantly impact on OIRR for either RFT or VPT group (P > 0.05). In women specifically, RFT displayed less resorption than VPT (P < 0.05). For treatment type, extraction cases demonstrated a lower degree of OIRR in RFT than VPT (P < 0.05), and notable greater OIRR in with-extraction group compared to no-extractions group was found in RFT (P < 0.05), but not in VPT (P > 0.05). Tooth type did not yield significant differences in OIRR overall; however, upper teeth and premolars experienced lower resorption in RFT than in VPT (P < 0.05). Cases treated with fixed appliance had higher OIRR in both RFT and VPT than those with clear aligners (P < 0.05). Age did not correlate significantly with OIRR for either group (P > 0.05). And duration of treatment positively correlated with OIRR for both types (RFT: r = 0.5506, P < 0.0001; VPT: r = 0.4371, P = 0.0002), so did root movement distance (RFT: r = 0.2955, P = 0.0140; VPT: r = 0.2790, P = 0.0206).
Conclusions:
RFT exhibit significantly less OIRR than VPT after orthodontic treatment. Treatment type, appliance type, duration of treatment and root movement distance are significant factors influencing OIRR. Personalized orthodontic treatment plans and vigilant monitoring are crucial to mitigate OIRR risks.
