The complete anatomy of the mandibular lingula: a meta-analysis with clinical implications

The objective of this meta-analysis was to investigate the anatomical variations of the mandibular lingula (ML) and its relationship with surrounding anatomical structures. Understanding such variations is crucial to help determine the site and depth of a successful inferior alveolar nerve (IAN) anaesthetic block as well as a safe area for oral and maxillofacial invasive procedures to minimise the risk of neurological or haematological damage to the inferior alveolar nerve.

A systematic search was conducted in which all studies were searched on the anatomy of ML. Major medical databases such as PubMed, Scopus, Embase, Web of Science, Google Scholar, and Cochrane Library were searched.

All the results were based on a total of 4694 subjects. The overall height of the ML was found to be 8.17 mm (SE = 0.22). The triangular type of ML was found to be the most common. The pooled prevalence of this variation was found to be 29.33% (LCI = 23.57%; HCI = 35.24%). The pooled prevalence of the nodular type was found to be 27.99% (LCI = 22.64%; HCI = 33.67%).

The present meta-analysis provides clinically relevant information regarding the shape, location, and height variations of the ML. Understanding such variations of the ML is crucial when performing malocclusion correction procedures that require the ML as a landmark, namely sagittal split ramus osteotomy, and intraoral vertical ramus osteotomy. Furthermore, effective anaesthetic blocks during oral and maxillofacial procedures can be accomplished with a higher success rate if the correct site of injection is identified. The possible locations of the ML should be considered to determine the location of the mandibular foramen and, therefore, the inferior alveolar bundle to prevent motor, sensory, or perfusion pathology during maxillofacial and oral procedures of the lower jaw.