Evidence map›Paper›PMID 42096836›Full record

ArticleInternational dental journal2026

Anatomical Predictors of Second Molar External Root Resorption: A Cone-Beam Computed Tomography Study of Impacted Third Molars.

Mingyue Wang, Jingyi Wang, Ieoktong U, Yumin Wu, Sien Zhang, Zhiguo Liu, Zongxi Wu

Abstract read
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Article in International dental journal, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

7 authors.

Mingyue WangHospital of Stomatology, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Clinical Research Center of Oral Diseases, Guangzhou, China.
Jingyi WangHospital of Stomatology, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Clinical Research Center of Oral Diseases, Guangzhou, China.
Ieoktong UHospital of Stomatology, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Clinical Research Center of Oral Diseases, Guangzhou, China.
Yumin WuHospital of Stomatology, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Clinical Research Center of Oral Diseases, Guangzhou, China.
Sien ZhangHospital of Stomatology, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Clinical Research Center of Oral Diseases, Guangzhou, China. Electronic address: zhangsen5@mail.sysu.edu.cn.
Zhiguo LiuHospital of Stomatology, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Clinical Research Center of Oral Diseases, Guangzhou, China. Electronic address: liuzhg6@mail.sysu.edu.cn.
Zongxi WuHospital of Stomatology, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Clinical Research Center of Oral Diseases, Guangzhou, China. Electronic address: wuzx65@mail.sysu.edu.cn.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectivesThis study aimed to identify anatomical and radiographic risk factors associated with second molar (M2) external root resorption (ERR) induced by impacted third molars (M3) using cone-beam computed tomography, providing a strategic framework for clinical decision-making regarding prophylactic extraction.

methodsA retrospective analysis was conducted on cone-beam computed tomography scans of 513 impacted M3s. Anatomical parameters, including M3 angulation, impaction depth (Pell and Gregory classification), and skeletal constraints (M3 to the posterior border of the maxilla, distance from the M3 root to the posterior border of the mandible, etc.) were quantified. The severity and anatomical location of M2 ERR were evaluated using stratified statistical methods to identify key predictors of resorption.

resultsIn the univariate analysis, M2 ERR severity was significantly associated with M3 impaction depth and skeletal space constraints rather than angulation alone (P < .05). Class C impaction with apical-third involvement represented the highest risk profile; notably, 100% of severe maxillary ERR cases were localized to the M2 apical third. In the multivariate model, an increased distance from the M3 to the posterior border of the maxilla (OR = 1.26) and a reduced cervical width of the M2 were key predictors of severity. Furthermore, a distinct sexual dimorphism was observed, with female patients exhibiting a significantly higher prevalence of severe maxillary ERR, likely due to more restricted skeletal space.

conclusionsThe severity of M2 ERR is primarily driven by impaction depth and anatomical constraints, particularly the limited space in the maxillary tuberosity and mandibular retromolar area. Class C impaction targeting the M2 apical third is the most critical risk factor for severe resorption. CLINICAL RELEVANCE: Clinicians should consider a proactive management strategy, prioritizing preventive M3 extraction in high-risk cases - specifically Class C impactions in female patients - to avoid irreversible pulp involvement and potential M2 loss. These findings support shifting from passive observation to early intervention based on specific anatomical risk profiles.

Indexed as

Cone-Beam Computed TomographyMolarMolar, ThirdRoot ResorptionTooth, ImpactedAdolescentAdultFemaleHumansMaleRetrospective StudiesRisk FactorsSex FactorsYoung AdultAnatomical risk factorsCone-beam computed tomographyExternal root resorptionImpacted third molarsSexual dimorphism

Identifiers

PMID42096836
PMCPMC13157144

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LicenceCC BY-NC-ND
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.