The Risk of Inferior Alveolar Nerve Injury According to the Position of the Mandibular Third Molar
Literature Review
DOI:
https://doi.org/10.29166/od.v28i1.9855Keywords:
Molar third, Mandibular nerve, radiography panoramic, cone beam computed tomographyAbstract
Objective: To critically analyze the evidence published between 2020 and 2025 on the risk of mandibular nerve injury, particularly its inferior alveolar branch (IAN), according to the position of the mandibular third molar and its relationship with the mandibular canal, integrating imaging, anatomical, and therapeutic findings applicable to the Ecuadorian context. Materials and methods: A literature review was conducted in PubMed/MEDLINE, Scopus, and Web of Science using MeSH/DeCS descriptors and free terms. For terminological standardization, the official descriptor “Mandibular Nerve” was used, complemented by terms related to the inferior alveolar nerve, mandibular third molar, mandibular canal, panoramic radiography, and cone-beam computed tomography (CBCT). Clinical-radiographic studies, systematic reviews, meta-analyses, and reviews with explicit methodology were included. The information was qualitatively synthesized by thematic axes and organized in a triangulation table. Results: A total of 40 publications were included. The evidence indicates that neurosensory risk increases in cases of close proximity between the roots and the mandibular canal, loss or discontinuity of the cortical bone, lingual or interradicular canal courses, and anatomical variants. Panoramic radiography is useful as an initial screening tool, although its bidimensional nature limits buccolingual assessment. CBCT should be selectively indicated when three-dimensional analysis may modify clinical decision-making. Conclusions: A stepwise approach, based on initial panoramic radiography and selective CBCT, together with anatomical stratification of the mandibular canal, allows safer surgical planning of mandibular third molar extraction, optimizes resources, and reduces neurosensory complications. In selected high-risk cases, coronectomy may be considered after individualized risk-benefit analysis and clinical follow-up.
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