Evaluation of microimplant anchorage in depressing maxillary elongated molars and CBCT assessment of root resorption risks

doi:10.19438/j.cjoms.2026.02.005

Abstract

Abstract: PURPOSE: To evaluate the clinical efficacy of microimplant anchorage(MIA) in the intrusion of overerupted maxillary molars and the risk of root resorption using CBCT. METHODS: A total of 119 patients with overerupted maxillary molars(130 overerupted maxillary molars in total) admitted to the 904th Hospital of the PLA Joint Logistic Support Force from February 2021 to May 2024 were selected, and all received molar intrusion treatment using MIA technology. CBCT scans were performed before and after treatment. The vertical distance from the molar to the palatal plane(ANS-PNS) was measured to assess the intrusion effect; the tooth length, alveolar bone height at the cervical margin, periodontal probing depth(PD), and modified bleeding index(mBI) were measured. Levander classification was used to evaluate root resorption, and Oral Health Impact Profile-14(OHIP-14) and dental function scale were used to assess patients' quality of life and dental function. RESULTS: All 130 overerupted maxillary molars achieved effective intrusion: the vertical distance from the molar to the ANS-PNS plane was (26.43±1.04) mm before treatment, which decreased to (24.51±1.02) mm after treatment, with an average intrusion of (1.92±0.29) mm. After treatment, the tooth length, alveolar bone height at the cervical margin were significantly improved compared with those before treatment (P<0.05). At 3 months after treatment, 30 molars(23.1%) had mild resorption, and 4 molars (3.1%) had moderate resorption; at 6 months after treatment, only 17 molars(13.1%) had residual mild resorption, and no severe/extreme severe resorption was observed. At 3 months after treatment, the OHIP-14 score decreased significantly, and the dental function score increased significantly(P<0.05). CONCLUSIONS: MIA has significant effect on the intrusion of overerupted maxillary molars. It can improve tooth morphology and periodontal status, enhance patients' function and quality of life, and has a low risk of root resorption.

Key words: CBCT, Microimplant anchorage, Maxillary elongation molars, Root resorption

CLC Number:

R782.1

Gu Meng, Li Yujia, Yuan Deyan. Evaluation of microimplant anchorage in depressing maxillary elongated molars and CBCT assessment of root resorption risks[J]. China Journal of Oral and Maxillofacial Surgery, 2026, 24(2): 128-132.

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