Impaction of Lower Third Molars and Their Association With Age: Radiological Perspectives

Soukaina Ryalat; Saif Aldeen AlRyalat; Zaid Kassob; Yazan Hassona; Mohammad H. Al-Shayyab and Faleh Sawair


BMC Oral Health. 2018;18(58) 

In This Article


Extraction of impacted molars remains one of the most commonly performed procedures in oral and maxillofacial surgery. Third molars are the most commonly impacted teeth, with an average worldwide rate of impaction of 24%.[1] According to a recent review, prophylactic extraction of asymptomatic third molars occurs in disorderly manner without clearly defined criteria.[2] It has been estimated that 54% of mandibular third molars are removed prophylactically without the presence of any subjective symptoms, and 30 - 50% of referred third molars are removed without any valid indications.[3,4] One reason for this is the difficulty in predicting which impacted tooth will cause complications if left unextracted.

The current general approach in dealing with impacted third molars is on the basis of clinical judgment; periodic evaluation by some clinicians and early extraction by others.[2] Most expected complications following third molar surgery include sensory nerve damage, dry socket, pain, swelling, trismus, infection and hemorrhage.[5] These complications are disturbing for young patients, especially if they become permanent in cases of inferior alveolar or lingual nerve injuries.[6] In addition to factors related to surgery, the position and angulations of third molars are strongly associated with the number and degree of postoperative morbidities.[7] The purpose of the present study of the pattern of eruption of mandibular third molars is to define the most appropriate age for prophylactic extraction of these teeth. Identification of eruption/impaction pattern of mandibular third molar would help to predict whether mandibular third molar will erupt or will remain impacted, therefore might help in clinical decision regarding the best timing of their extraction.