A study on the incidence of retromolar foramen in South Indian adult dried human mandibles and its clinical relevance.

Background: The retromolar foramen is one of the most important non-metrical anatomical variants in the mandible. The present study describes the incidence of retromolar foramen in South Indian adult dried mandibles and its clinical relevance. Methods: One hundred South Indian adult dried mandibles of unknown sex were studied at the Department of Anatomy, MVJ Medical College, Bangalore for the presence of retromolar foramen. Its location, size, shape, distance of the foramen if present from the posterior border of socket for 3rd molar tooth, anterior border of ramus of the mandible were measured. Results: Retromolar foramen was present in 16 (16%) of the mandibles. Out of the 16 mandibles, it was present bilaterally in 3 (3%) mandibles and unilaterally in 13 (13%) mandibles (In 3 (3%) on the right side and in 10 (10%) on the left side). The mean diameter of the foramen was 1.33mm (range - 1.10-1.92 mm). It was oval in shape in 9 (9%) and rounded in shape in 7 (7%) mandibles. The mean distance of retromolar foramen from the posterior border of socket for 3rd molar tooth and anterior border of ramus were 6.15 mm (2.23-12.10) and 8.02 mm (3.24-13.12) respectively. Conclusions: The knowledge about the incidence of the retromolar foramen is important for dental surgeons during various anaesthetic, implantation and surgical procedures of the mandible, especially during extraction of the lower last molar tooth.

Characterization of stem cells from the pulp of unerupted third molar tooth.

Context: Dental pulp stem cells (DPSCs) are the most diagnosed type of stem cells isolated from dental tissues. Previous studies demonstrate that tissues in earlier stages of development could be better stem cell resources for tissue engineering. Aims: In this study, aiming at finding younger stem cell resources, we chose the pulp of human unerupted third molar teeth when the crown was completely formed and the roots had not begun their development, Nolla's 6 th developmental stage (N6 th ). Materials and Methods: Surgical removal of the third molar was performed by aseptic technique with minimal trauma. The tissues were digested enzymatically and the resulted single cells were cultured. Immunophenotypic characterization of the cells was done via immunocytochemistry, immunofluorescence, and flow cytometry assays. Adipogenic and osteogenic differentiation potential of these cells was examined and confirmed by histochemical staining and reverse transcription-polymerase chain reaction analysis. Statistical Analysis Used: This study is descriptive. Results: N6 th -unerupted dental pulp cultured cells expressed DPSC markers: Vimentin, CD73, CD90, CD105, CD166, CD44, CD146, and STRO-1, but did not express hematopoietic cell markers: CD14, CD34, CD45, HLA-DR and were also negative for dentin sialoprotein negative showing an undifferentiated preodontogenic state. Adipocytes differentiated from N6 th -DPSCs were positively stained with Oil-Red-O and expressed both early and late adipocyte specific genes. Formation of Alizarin-red positive condensed calcium-phosphate nodules accompanied by strong expression of two osteogenic mRNAs, exhibited osteogenic differentiation. Conclusion: Based on the results of this study, we suggest that N6 th -DMSCs are a viable choice for cryo-banking and future usage in regenerative therapies; however, more investigations are necessary before clinical application can commence.

Odontoma complejo extenso asociado a tercer molar retenido en base de mandíbula: relato de caso clínico / Extensive complex odontoma associated with an unerupted third molar in the mandible base: case Report

Los odontomas son tumores odontogénicos mixtos, diferenciados según sus características anatómicas en odontoma compuesto y complejo. El odontoma complejo es el más raro y normalmente se presenta con un curso evolutivo asintomático, puede ocasionar retención, mal posición dentaria y el aumento de volumen local. La terapéutica incluye exéresis completa de lesión. La evaluación histológica es importante, debido a la rara posibilidad de tratarse de un odontoma ameloblástico. El presente trabajo presenta un caso de una paciente de 18 años, transferida por un odontólogo para la evaluación de una lesión en la mandíbula del lado derecho. En la imagen radiográfica panorámica, se observó un área extensa radiopaca irregular, de evolución indeterminada, con aproximadamente 5 centímetros de diámetro, en la región del cuerpo y ángulo mandibular derecho. El tercer molar inferior derecho retenido y orientado hacia la base de la mandíbula, circunscrito por un área radiolúcida y el segundo molar inferior derecho ausente. Al examen físico intrabucal, observamos una tumefacción dura a la palpación en la superficie lingual de esta región. El diagnóstico presuntivo fue de odontoma complejo y quiste dentígero envolviendo el tercer molar. El examen microscópico reveló la presencia de folículos pericoronarios envolviendo el diente tercero molar inferior derecho y, en el interior de la masa removida, presencia de conglomerado irregular de esmalte, dentina, cemento y tejido pulpar. El diagnóstico final fue de odontoma complejo. La paciente se encontraba en observación de 5 años, sin signos clínicos y radiográficos de recidiva

Odontomas are mixed tumors which can be divided into two types: the complex and the compound odontoma. Complex odontoma is rare, and usually presents an asymptomatic course, being able to cause dental impaction, wrong teeth position and local volume increase. Surgical treatment of these lesions consists of local removal and curettage. The microscopic evaluation is important, because of the possibility of an ameloblastic odontoma. We report a case of an 18-year-old woman with a lesion involving the right mandible. In panoramic radiography we observed an extensive irregular radiopaque area with unknown evolution and approximately 5cm of diameter, in molar mandible region. Teeth 48 impacted and displaced to the mandible base, involved for a radiolucid area and absence of 47 tooth. The previous diagnosis was complex odontoma and dentigerous cyst involving the third molar. The microscopic examination showed a dental follicle surrounding tooth 48 and in the removed mass, haphazard fashion with enamel, dentin, cementum and pulp. Final microscopical diagnosis was complex odontoma. The patient is being followed-up for five years and no clinical and radiological evidences of recurrence were found

Management of the Third Molar Tooth in Mandibular Angle Fracture

The management of the third molar tooth in mandibular angle fracture is still controversial. Retrospective analysis of 197 cases of mandibular angle fractures associated with third molar tooth was undertaken. Selective prophylactic extraction of the third molar teeth were undertaken in 66 cases. The third molar teeth were retained in 131 fractures. The indication of extraction of the third molar teeth in mandibular angle fracture were as follows: 1) interfering with reduction of the fracture; 2) excessive mobility; 3) exposure of tooth root due to distraction of the fracture; 4) fractured teeth; 5) severely carious tooth 6) infected supporting structure. There were no significant differences between the complication rate in the "tooth removed" group and "tooth retained" group. Complications were minimal. Therefore proper management of the third molar tooth in mandibular angle fracture will minimize complication.