TL;DR: This case report is the first in the literature in which concrescence is observed between a third molar and a supernumerary fourth molar in the mandible.
Abstract: Concrescence represents a rare developmental anomaly in which two fully formed teeth are joined along the root surfaces by cementum. Maxillary molars are the teeth most frequently involved, especially a third molar and a supernumerary tooth. Very few cases have been reported about the concrescence of a third molar and a supernumerary tooth. According to our current knowledge, this case report is the first in the literature in which concrescence is observed between a third molar and a supernumerary fourth molar in the mandible.
TL;DR: The impossibility of assigning precise diagnostic terms, such as germination, fusion, macrodontia, and concrescence, to dental twinning anomalies because the entire course of odontogenesis cannot be witnessed is described.
Abstract: Dental twinning results from abnormal events in the embryologic development of teeth. This paper describes the impossibility of assigning precise diagnostic terms, such as germination, fusion, macrodontia, and concrescence, to dental twinning anomalies because the entire course of odontogenesis cannot be witnessed. Traditional nomenclature is reviewed and seven cases that exemplify the principle are presented. Modification of nomenclature to describe dental twinning defects is suggested.
TL;DR: It is concluded that double teeth in primary dentition have to be carefully analysed as they may be associated with anomalies in the permanent dentition.
Abstract: Odontogenic anomalies can occur as a result of conjoining or twinning defects. These include fusion, gemination and concrescence. This article presents two case reports of double teeth. In the first case reported, a 4 -year-old white boy presented primary double teeth associated to the absence of the right permanent mandibular lateral incisor. In the second case, a 5-year-old white girl had a family history of anomaly in primary dentition. The girl and her mother presented double teeth in the primary dentition. Her mother showed hypodontia in the permanent dentition. Extra and intra oral clinical examination was made in both cases. Radiographic analyses showed the involvement of the permanent tooth. Authors conclude that double teeth in primary dentition have to be carefully analysed as they may be associated with anomalies in the permanent dentition. Correct diagnosis of the condition implicates in a better prognosis for the patient.