Comprehensive analysis of ectopic mandibular third molar: a rare clinical entity revisited

The ectopic tooth is usually diagnosed when the tooth is displaced from its standard anatomic site. Due to the rarity of this condition, the etiology, clinical manifestations and optimal management of ectopic mandibular third molar are not well-established until now. Therefore, in this article, Yaping Wu et al found that Ectopic mandibular third molars are usually found in patients with middle ages and in upper and middle ramus of mandible. 

The ectopic mandibular third molar is an unusual clinical structure with inadequately understood etiology. The study aimed to describe its radiographic, clinical, and epidemiological characteristics, and treatment by integrating and interpreting the cases handled at Nanjing Medical University, China concurrently with earlier reported cases.

A new ectopic mandibular third molar definition and classification were suggested on the basis of its anatomic position on panoramic images. The University literature (1990–2016) and the disease registry identified the 51 teeth in 49 patients and 38 mandibular third molars in 37 patients, respectively. Further, these cases categorized and compared as per the institution classification protocol. The data concerning radiographic, clinical, and epidemiological characteristics were obtained and examined.

All the ectopic teeth were classified into four levels. The first level (upper ramus) consists of 33 teeth, level II (middle ramus) consists of 32, level III (mandibular angle) consists of 15 and level IV (mandibular body) comprises of nine. The primary clinical presentations involved swelling, pain, and restricted mouth opening, although sometimes asymptomatic. Maximum of the teeth were correlated with pathological lesions. Management approaches involved a clinical monitor and surgical extraction by intra- or extraoral approach with desirable results. Treatment choices and clinical presentations for these teeth were considerably related with their ectopic positions as per analysis were done by the researchers.

Ectopic mandibular third molars are generally observed among the patients with midlife and in upper and middle ramus of the mandible. Surgery is chosen to extract these ectopic teeth and related pathologies when possible.