Ameloblastic fibrosarcoma (AFS) is an extremely rare malignant odontogenic tumor characterized with benign ameloblastic cells islands and malignant mesenchymal component. While two-thirds of AFS seem to arise de novo, but one-third develops from recurrent ameloblastic fibroma (AF) or ameloblastic fibro-odontomas (AFO). Pathological distinction of malignant transformation is essential for appropriate treatment. The patient was a 28 years old man. Since the primary tumor was excised, the mass recurred 2 years later. The recurrent tumor was diagnosed as AFS. Chief complaint was pain in the right mandible. Computer tomography finding revealed multilocular intrabony lesion with radiopaque substance in the primary lesion. In the recurrent lesion cortical bone destruction was found. Microscopically, both the primary and recurrent lesions showed benign ameloblastic follicles with myxoid or highly cellular mesenchymal proliferation. The histological difference between primary and recurrent lesions were that foci of dental hard tissue composed of enamel and dentin were found only in the primary lesion, whereas nuclear pleomorphism was aggrevated in the recurrent lesion. The histological criteria determining malignancy were discussed.

Calcifying cystic odontogenic tumor (CCOT), also known as calcifying odontogenic cyst or Gorin cyst is a rare developmental lesion which arises from odontogenic epithelium. It has been classified as a benign odontogenic neoplasm related to odontogenic apparatus by the World Health Organization. CCOT may be associated with other odontogenic tumors, most frequently odontoma, a finding that is a rare event in other types of odontogenic cysts or tumors. This report describes a case of hybrid odontogenic tumor composed of CCOT and ameloblastic fibroma-odontoma of the impacted right maxillary canine region that occurred in a 14-year-old female.

Ameloblastic fibro-odontoma has been defined as a lesion similar to ameloblastic fibroma by WHO, as it shows inductive changes which forms enamel and dentin. Ameloblastic fibro-odontoma is a very rare mixed dentition tumor in children, and the symptom shows indolent edema in maxillary and mandibular molar area. The prevalence is two times higher in male than in female, and two times higher in maxilla than in mandible. Radiologically, it shows clear border and characteristics of both fibroma and odontoma histologically. This review reports a case that a 4-year old female visited in dental clinic of this school for edema as chief complaint in Feb, 2012. Emergency surgical curettage was performed right after initial diagnosis as odontoma, then confirmed diagnosis as Ameloblastic fibro- odontoma after biopsy. Currently, after 6 month, no sign of recurrence can be seen. Ameloblastic fibro-odontoma is very rare mixed dentition tumor. Moreover, as it is the case of female maxilla, this case is worth of publishing. Furthermore, accurate diagnosis of Ameloblastic fibro-odontoma is difficult. This review is published for accurate diagnosis through differential diagnosis of several important mixed dentition tumors.

This is a case reporL of a ra re mi xed odontogenic tumo r, amelob lastic fibro-odontoma in the poste1'ior of r ight ma nd tlbe A 2-year - olcl ma le pa ti enL was referred to our department ['or large tumorous lesion 011 ri ght mandible Radiograph ic examination s howed la rge radi opaque and rad iolu cent lesion with impacted and unerupted tooth, #44‘ #45 , #46 #85 , AJ'Ler s urgi cal enuclea Li on & cu rettage of t he mass , the tumor was confirmed to ameloblastic fibro-odontoma. lt was composed with c1 enta l orga ns a ncl is la nd of odontogeni c epithelium embedded in a cell - ri ch mesenchymal s troma, AIso‘ we ca rri ed out an immunohi stochemical study. The resul ts s howed positive CK7 staining. and showed weekly positi ve for Bcl - 2‘ Ki - 67 s Laining, while CEA, CK8‘ CKl2, CKl6 showed l1egative, Follow-up studies have shown no tumot recurrence for 2 yea rs ,