高下牙槽神经损伤风险下颌第三磨牙相关下颌管皮质骨 缺损的危险因素研究

doi:10.13591/j.cnki.kqyx.2026.04.005

Abstract

Abstract:

Objective To identify risk factors influencing cortical bone defect of the mandibular canal related to mandibular third molar with high-risk of inferior alveolar nerve injury (IAN-risk M3). Methods A retrospective study was conducted on 2 516 patients (3 389 M3s) with IAN-risk M3s who attended the Affiliated Stomatological Hospital of Nanjing Medical University between January 2018 and December 2021. All patients underwent panoramic radiography and cone-beam computed tomography (CBCT). Mandibular canal cortical bone condition was assessed on CBCT, and multivariate Logistic regression analysis was performed to determine significant risk factors for cortical bone defect. Results The incidence of mandibular canal cortical bone defect associated with IAN-risk M3 was 38.15%. Mesioangular, middle and low levels impactions, Class Ⅱ and Class Ⅲ impactions, mandibular canal positioned lingual to or between the M3 roots, and a narrow canal morphology were significant risk factors for cortical bone defect. Conclusion Mandibular canal cortical bone defect associated with IAN-risk M3s have a relatively high prevalence and were significantly correlated with radiographic characteristics. Preoperative CBCT evaluation in such cases can assist clinicians in optimizing surgical strategies for third molar extraction and reducing the risk of inferior alveolar nerve injury.

Key words: mandibular third molar, mandibular canal cortical bone defect, CBCT, risk factors

CLC Number:

R782.11

YANG Haochuan, YANG Shengjun, LIU Jingyi, XU Binhao, WANG Dongmiao. Risk factors for cortical bone defect of the mandibular canal related to mandibular third molars with high-risk of inferior alveolar nerve injury[J]. Stomatology, 2026, 46(4): 266-271.

Figures/Tables 8

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References 30

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相关因素		下颌管皮质骨状态				P
相关因素		完整		局部缺损		P
性别	男性	926	(64.44%)	511	(35.56%)	0.001^*
性别	女性	1 170	(59.94%)	782	(40.06%)	0.001^*
年龄/岁	18~25	550	(60.98%)	352	(39.02%)	0.063
	26~35	823	(59.99%)	549	(40.01%)
	36~45	512	(65.64%)	268	(34.36%)
	46~55	211	(62.99%)	124	(37.01%)
Winter分类(曲面断层片)	近中	484	(50.26%)	479	(49.74%)	<0.000 1^*
	水平	566	(52.85%)	505	(47.15%)
	垂直	1 046	(77.20%)	309	(22.80%)
Pell-Gregory分类(基于第二磨牙咬合平面,曲面断层片)	高位	1 115	(81.15%)	259	(18.85%)	<0.000 1^*
	中位	786	(51.37%)	744	(48.63%)
	低位	195	(40.21%)	290	(59.79%)
Pell-Gregory分类(基于下颌升支,曲面断层片)	Ⅰ类	762	(84.57%)	139	(15.43%)	<0.000 1^*
	Ⅱ类	888	(63.66%)	507	(36.34%)
	Ⅲ类	446	(40.81%)	647	(59.19%)
下颌管相对M3牙根的位置(CBCT)	下方	816	(70.77%)	337	(29.23%)	<0.000 1^*
	颊侧	1 173	(67.92%)	554	(32.08%)
	舌侧	101	(22.15%)	355	(77.85%)
	中间	6	(11.32%)	47	(88.68%)
下颌管形态(CBCT)	圆形/卵圆形	2 014	(88.02%)	274	(11.98%)	<0.0001^*
下颌管形态(CBCT)	狭窄型	82	(7.45%)	1 019	(92.55%)	<0.0001^*

类别		皮质骨状态		P	OR (95%CI)
类别		完整	局部缺损	P	OR (95%CI)
性别	男性	926(64.44%)	511(35.56%)
	女性	1 170(59.94%)	782(40.06%)	0.090	1.227(0.968,1.555)
年龄	18~25	550(60.98%)	352(39.02%)
	26~35	823(59.99%)	549(40.01%)	0.139	1.237(0.933,1.639)
	36~45	512(65.64%)	268(34.36%)	0.808	1.042(0.746,1.456)
	46~55	211(62.99%)	124(37.01%)	0.118	1.402(0.918,2.140)
Winter分类(曲面断层片)	近中	484(50.26%)	479(49.74%)
	水平	566(52.85%)	505(47.15%)	0.322	0.855(0.627,1.166)
	垂直	1 046(77.20%)	309(22.80%)	0.238	0.808(0.568,1.151)
Pell-Gregory分类(基于第二磨牙咬合平面,曲面断层片)	高位	1 115(81.15%)	259(18.85%)
	中位	786(51.37%)	744(48.63%)	0.007^*	1.587(1.133,2.223)
	低位	195(40.21%)	290(59.79%)	0.047^*	1.569(1.006,2.449)
Pell-Gregory分类(基于下颌升支,曲面断层片)	Ⅰ类	762(84.57%)	139(15.43%)
	Ⅱ类	888(63.66%)	507(36.34%)	0.082	1.389(0.959,2.012)
	Ⅲ类	446(40.81%)	647(59.19%)	<0.0001^*	2.504(1.597,3.926)
下颌管相对M3牙根的位置(CBCT)	下方	816(70.77%)	337(29.23%)
	颊侧	1 173(67.92%)	554(32.08%)	0.055	0.783(0.609,1.005)
	舌侧	101(22.15%)	355(77.85%)	<0.000 1^*	2.365(1.581,3.537)
	中间	6(11.32%)	47(88.68%)	0.020^*	4.243(1.250,14.408)
下颌管形态(CBCT)	圆形/卵圆形	2 014(88.02%)	274(11.98%)
	狭窄型	82(7.45%)	1 019(92.55%)	<0.000 1^*	60.615(46.408,70.181)

Risk factors for cortical bone defect of the mandibular canal related to mandibular third molars with high-risk of inferior alveolar nerve injury

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