Mandibular Third Molar Impaction: Review of Literature and a Proposal of a Classification

Abstract

ObjectivesThe purpose of present article was to review impacted mandibular third molar aetiology, clinical anatomy, radiologic examination, surgical treatment and possible complications, as well as to create new mandibular third molar impaction and extraction difficulty degree classification based on anatomical and radiologic findings and literature review results.Material and MethodsLiterature was selected through a search of PubMed, Embase and Cochrane electronic databases. The keywords used for search were mandibular third molar, impacted mandibular third molar, inferior alveolar nerve injury third molar, lingual nerve injury third molar. The search was restricted to English language articles, published from 1976 to April 2013. Additionally, a manual search in the major anatomy and oral surgery journals and books was performed. The publications there selected by including clinical and human anatomy studies.ResultsIn total 75 literature sources were obtained and reviewed. Impacted mandibular third molar aetiology, clinical anatomy, radiographic examination, surgical extraction of and possible complications, classifications and risk factors were discussed. New mandibular third molar impaction and extraction difficulty degree classification based on anatomical and radiologic findings and literature review results was proposed.ConclusionsThe classification proposed here based on anatomical and radiological impacted mandibular third molar features is promising to be a helpful tool for impacted tooth assessment as well as for planning for surgical operation. Further clinical studies should be conducted for new classification validation and reliability evaluation.

Comparison of Piezosurgery and Conventional Rotary Instruments for Removal of Impacted Mandibular Third Molars: A Randomized Controlled Clinical and Radiographic Trial

“…Approximately 20% of the population has impacted teeth, where mandibular and maxillary third molars are the most common [1]. …”

“…Surgical removal of these teeth is usually correlated with postoperative pain, swelling, and trismus whereas complications such as infection, dry socket, trigeminal nerve injuries, and, rarely, fracture of the mandible are less common to occur [1, 3]. …”

Anatomical Relationship of Lingual Nerve to the Region of Mandibular Third Molar

“…The LN often lies close to the cortical plate. So, there is a high risk of LN damage using the lingual split technique or elevating the third molar flap medially to the distoangular recess [3]. …”

Accidental Displacement of Third Molar into the Sublingual Space: a Case Report

“…Differently, in the present report an entire third molar was displaced into the sublingual space, indicating that the tooth was in a favourable position for extraction, in which the crown resection was not necessary. Besides, wrong surgical techniques are closely related to the transoperative displacement of third molars [15], potentially justifying the accident reported in our study. The same was observed in the reports of Pippi and Perfetti [16], and Olusanya et al [17], in which general practitioners performed unsuccessful extractions, highlighting the relevance of not performing surgical interventions without having a proper expertise on the field.…”