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The removal of mandibular third molars can be complicated by injury to the inferior alveolar nerve (IAN). Coronectomy retains the tooth root; this method has been found to be preferable to extraction in the context of mandibular third molars. A failed coronectomy may cause mobilization of these roots, thereby requiring a subsequent extraction. Having undergone a previous coronectomy, extraction is then safer as the roots usually migrate away from the IAN. Computed tomography is more accurate than radiography when imaging mandibular third molars pre-operatively owing to its three-dimensional nature. Longer studies need to be conducted to evaluate the long term benefits of coronectomy.
CPD/Clinical Relevance: The removal of mandibular third molars can be complicated by the presence of the close lying inferior alveolar nerve. Coronectomy can be useful in this setting and therefore it is important to be aware of the pros and cons of this technique.
Article
The removal of mandibular third molars is a common procedure. According to the NICE guidelines, these are removed as a result of pathological changes or for prophylactic purposes for pathology-free impacted third molars.1,2 This is a relatively routine procedure, however, complications can occur due to the close proximity of the roots of these teeth to the inferior alveolar nerve (IAN), which can be damaged as a result of removal, with an incidence of up to 8%.1
One method of management is coronectomy, which is the deliberate retention of the tooth root, therefore preventing potential damage to the IAN.3 Radiographic features can be used to assess the potential risk of injury, including:
This paper reviews clinical studies with regards to aspects such as the development of imaging techniques, proximity to IAN, success rate and possible long-term complications, to evaluate the overall effectiveness of this procedure.
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