Effect of two-stage crown-root extraction method on complications after extraction of high-risk mandibular third molars

doi:10.19438/j.cjoms.2025.06.003

Abstract

Abstract: PURPOSE: To observe the effects of two-stage crown-root extraction and conventional single-stage extraction on the complications after high-risk mandibular third molar (M3M) extraction. METHODS: A prospective non-randomized controlled design was adopted, with 145 high-risk M3Ms divided into two groups. For the experimental group (59 M3Ms), the two-stage crown-root extraction method was used: crown amputation was performed in the first stage, and the remaining tooth roots were extracted in the second stage 3-6 months later. For the control group (86 M3Ms), the conventional one-time extraction method was used to remove both the crown and root of M3M. The conditions of bleeding, infection, postoperative reactions (pain, swelling, and trismus), and inferior alveolar nerve (IAN) injury within 7 days after surgery were compared between the two groups. RESULTS: No statistically significant difference in postoperative hemorrhage was observed between the two groups within 7 days(P>0.05). The experimental group exhibited a higher infection rate after the first stage of surgery, but the postoperative reactions such as pain, swelling and trismus were less than that of the control group, with statistically significant differences between the two groups(P<0.05). Notably, no IAN injuries occurred in the experimental group, whereas the incidence of IAN injuries in the control group was 13.95%(12/86), demonstrating a statistically significant difference (P<0.05). CONCLUSIONS: Although the incidence of infection after the first-stage surgery is relatively high, the two-stage crown-root extraction method for removing high-risk M3M can effectively reduce postoperative complications, especially the risk of IAN injuries, providing a new option for the extraction of high-risk M3M with radiographically confirmed inferior alveolar canal compression.

Key words: Coronectomy, Mandibular third molar, Inferior alveolar nerve, Postoperative complications

CLC Number:

R782.11

Liu Xiangqi, Luo Xueting, Chen Jianghai, Liu Yuhao, Chen Xiangyi, Kuang Shijun. Effect of two-stage crown-root extraction method on complications after extraction of high-risk mandibular third molars[J]. China Journal of Oral and Maxillofacial Surgery, 2025, 23(6): 553-560.

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