1. Oral medicine Done by Abdulaziz m. ghannam 0610052

2. Personal data  Name/A.S.G  Age/16  Sex/ male  Nationality/Saudi  Occupation/student

3. Patient history Chief complain: He wants to check his teeth. Medical history: Not significant. Family history: Not significant. dental history & habits: Not significant.

4. Clinical examination Extra oral examination: Not significant.

10. Clinical examination Intra oral examination: Not significant, except for the impacted left lower canine

15. radiographs

16. radiographs Radiograph interpretation report: An OPG showing a mixed lesion localized at the left region of the mandible extending from the distal of the lower lateral to the mesial side of the first left premolar, the lesion is large rounded and appear as RO with RL rim of fibrous capsule and extend from the apical third of the lateral to near the inferior of the mandible displacing the left impacted canine with some root resorption, the teeth #37,38 and 48 are congenitally missing. Small multilocular RL lesion at the region of the teeth # 37 & 38 may be O.K.C or early stage of amiloblastoma

18. radiographs

19. definitive diagnosis Odontoma(complex)

20. odontoma Def/An odontoma in which the various odontogenic tissues appear in a haphazard arrangement that bears no resemblence to teeth. Def/a non-neoplastic malformation, a hamartoma, consisting of a mixture of enamel, dentine and cementum. Hamartoma: a benign tumor-like nodule composed of an overgrowth of mature cells and tissues that normally occur in the effected part, but with disorganization and often with one element predominating.

21. Treatment plan The treatment of choice is the Surgical treatment and the biopsy can be done during surgery. ….but

22. Cont. The patient refuse the surgery because of his financial status,so we well proceed with a follow up approach.

23. Follow up

29. Related topic Nestin expression in odontoblasts and odontogenic ectomesenchymal tissue of odontogenic tumours

30. Background: Nestin, one of the intermediate filaments constituting the cytoskeleton, is a marker of neural stem cells or progenitor cells. Its expression is also related to tooth development and repair of dentine.

31. :Aims The aim of this study was to investigate nestin expression in various odontogenic tumours and evaluate its usefulness for histopathological diagnosis.

32. Methods They studied formalin fixed, paraffin embedded specimens from 129 cases of odontogenic tumours and 9 of mandibular intraosseous myxoma.

33. After characterisation of odontogenic ectomesenchymal tissues in these tumours using antibodies to vimentin, desmin, neurofilament, and glial fibrillary acidic protein, we immunohistochemically examined nestin expression.

34. Results No differentiation towards muscle and nervous tissues was found in the odontogenic ectomesenchymal tissues. Although almost all the ameloblastomas and malignant ameloblastomas were negative for nestin, odontogenic ectomesenchyme in the odontogenic mixed tumours demonstrated nestin immunolocalisation, particularly in the region adjacent to the odontogenic epithelium.

35. Odontoblasts and their processes, pulp cells near the positive odontoblasts, and flat cells adhering to the dentine showed immunoreaction with nestin in the odontomas and odontoma ‐ like component in the ameloblastic fibro ‐ odontomas. Neoplastic cells in almost half cases of jaw myxoma and one case of odontogenic fibroma expressed nestin.

36. Parenchyma and stoma cells of ameloblastoma showed no nestin immunoreactivity.

37. Odontoma showed nestin expression in the odontoblasts and their processes in the dental tubules. Pulp cells adjacent to the odontoblasts gave a positive reaction (arrows).

38. Conclusions The distribution of nestin in the odontogenic mixed tumours suggests that nestin expression in the odontogenic ectomesenchyme is upregulated by stimulation from odontogenic epithelium. In addition, nestin may also be involved in the differentiation from pulp cells to odontoblasts in odontogenic tumours. Therefore, nestin is a useful marker for the odontogenic ectomesenchyme and odontoblasts in odontogenic tumours.

39. Nestin, one of the intermediate filaments constituting the cytoskeleton, is a marker of neural stem cells or progenitor cells. Its expression is also related to tooth development and repair of dentine.

40. Referances 1-Martine S, Michael G : benign tumors of the oral cavity, Burket’s oral medicine, 11 th edition (2008). 2-1. Lendahl U, Zimmerman L B, McKay R D. CNS stem cells express a new class of intermediate filament protein. Cell 1999. 60585–595.