Reactive gingival lesions: a retrospective study of 2,439 cases.

OBJECTIVE: To identify the clinicopathologic features of epulides in West China and to compare these data with those of previous studies from other countries. METHOD AND MATERIALS: Demographics; clinical data including gender, age, and chief complaints of the patients; and the type, size and location, duration, diagnosis, and histologic features of the lesion were studied from among biopsy specimens and clinical records at West China College of Stomatology from January 1951 to July 2005. RESULTS: A total of 2,439 epulides were identified. Epulides found were peripheral fibroma (PF: 1,489, 61.05%), peripheral ossifying fibroma (POF: 431, 17.67%), pyogenic granuloma (PG: 482, 19.76%), and peripheral giant cell granuloma (PGCG: 37, 1.52%). The total ratio of males to females was 1:1.40. Specifically, the ratios were 1:1.31 for PF, 1:1.99 for PG, and 1:1.47 for PGCG (all P < .001). The peak incidence of epulides fell in the third to sixth decade of life overall, the fifth to sixth decade for PF and POF, and the third to fourth decade for PG. CONCLUSIONS: Among the 4 kinds of reactive lesions, PF had the highest incidence and PG had the lowest incidence in Chinese patients. There were also differences in type, sex, age, location, duration, and histologic features: PF was the most common type; all of the epulides except PGCG showed a predilection for females; PG was more prevalent among young patients; and POF lasted much longer than other lesions. Differences in the distribution of the 4 types of lesion were also found among various ethnic groups.

Ameloblastic fibro-odontosarcoma of the mandible with active epithelial proliferation: A rare case report.

Ameloblastic fibro-odontosarcoma (AFOS) is an extremely rare subtype of odontogenic sarcoma, with no more than 19 cases reported in the English literature to date. AFOS is a biphasic neoplasm, with deposits of dentin and enamel matrix. We herein present a case of AFOS with active epithelial proliferation in a 31-year-old female patient. The patient was referred to the West China Hospital of Stomatology (Chengdu, China) due to a 6-month history of a swelling in the left mandible. Following clinical and radiological examination, the initial preoperative diagnosis was ameloblastoma, with local invasion and the possibility of malignant transformation. Left hemimandibular resection was subsequently performed. The postoperative histopathological diagnosis was AFOS, accompanied by active epithelial proliferation. Immunohistochemically, cytokeratin (CK)14 and CK19 were intensely positive in the epithelium, whereas the mesenchymal cells were strongly positive for vimentin. The Ki-67 labeling index was considerably higher in the mesenchymal component (mean, 40%) compared with that in the epithelial element (mean, 5-8%). Three months after the surgical procedure, the patient remained clinically and radiologically disease-free.

Primary intraosseous squamous cell carcinoma in pre-existing keratocystic odontogenic tumor: A case report and literature review.

Primary intraosseous squamous cell carcinoma (PIOSCC) is a rare type of odontogenic carcinoma that arises within the jaws. PIOSCC has no initial connection with oral mucosa and possibly develops from the residues of the odontogenic epithelium or from an odontogenic cyst or tumor. The diagnosis of PIOSCC can be difficult as it must be differentiated from other odontogenic carcinomas, such as malignant ameloblastoma, from SCCs arising from the overlying oral mucosa, from the primary tumors of the maxillary sinus or nasal mucosa, and from the tumors that have metastasized to the jaws from other primary sites. The present study reported a rare case of a 59-year-old male patient with a course of keratocystic odontogenic tumor for 25 years, between 1988 and 2013, which eventually transformed into PIOSCC after at least five recurrences and corresponding treatments. The mandible excision and titanium plate reconstruction was performed. Follow-up examinations have revealed no sign of recurrence thus far. The present study discussed this case from three aspects of clinical history, radiological examination and pathological features.

[Ossifying fibromyxoid tumor in the mandible: a case report].

Ossifying fibromyxoid tumor is an uncommon neoplasm with uncertain histogenesis. This tumor is usually characterized by a small, painless mass in the subcutaneous tissue or limb muscles. In this case, an ossifying fibromyxoid tumor of the mandible was reported, and relevant literature was reviewed.

Ghost cell odontogenic carcinoma arising from calcifying cystic odontogenic tumor: a case report.

Ghost cell odontogenic carcinoma (GCOC) is an exceptionally rare and malignant odontogenic tumor with aggressive growth characteristics. We describe a case of GCOC which was considerably derived from a previously resected calcifying cystic odontogenic tumor (CCOT). Cellular atypia, mitotic activity, Ki-67 labeling index and matrix metalloprotease-9 positive expression rate were all increased in the currently resected specimen compared to the initial one. This is a rare case of malignant transformation of CCOT to GCOC with respect to its histopathological and immunohistochemical findings.

Solid variant of keratocystic odontogenic tumor with ameloblastomatous transformation: a case report and review of the literature.

The solid variant of keratocystic odontogenic tumor is an extremely rare tumor. Its clinical and pathologic features remain poorly defined, even in the 2005 World Health Organization odontogenic tumor classification. We report an unusual lesion in a 38-year-old female Chinese patient. The lesion demonstrated the solid or multiple cystic architecture of a keratocystic odontogenic tumor, but also exhibited ameloblastomalike lining epithelium in some areas. The complex histopathology made a pathologic diagnosis difficult. Finally, the lesion was diagnosed as solid variant of keratocystic odontogenic tumor with ameloblastomatous transformation. We present the clinical and pathologic details of the case, and review the relevant literature.

Biodegradable thermosensitive hydrogel for SAHA and DDP delivery: therapeutic effects on oral squamous cell carcinoma xenografts.

BACKGROUND: OSCC is one of the most common malignancies and numerous clinical agents currently applied in combinative chemotherapy. Here we reported a novel therapeutic strategy, SAHA and DDP-loaded PECE (SAHA-DDP/PECE), can improve the therapeutic effects of intratumorally chemotherapy on OSCC cell xenografts. OBJECTIVE/PURPOSE: The objective of this study was to evaluate the therapeutic efficacy of the SAHA-DDP/PECE in situ controlled drug delivery system on OSCC cell xenografts. METHODS: A biodegradable and thermosensitive hydrogel was successfully developed to load SAHA and DDP. Tumor-beared mice were intratumorally administered with SAHA-DDP/PECE at 50 mg/kg (SAHA) +2 mg/kg (DDP) in 100 ul PECE hydrogel every two weeks, SAHA-DDP at 50 mg/kg(SAHA) +2 mg/kg(DDP) in NS, 2 mg/kg DDP solution, 50 mg/kg SAHA solution, equal volume of PECE hydrogel, or equal volume of NS on the same schedule, respectively. The antineoplastic actions of SAHA and DDP alone and in combination were evaluated using the determination of tumor volume, immunohistochemistry, western blot, and TUNEL analysis. RESULTS: The hydrogel system was a free-flowing sol at 10 °C, become gel at body temperature, and could sustain more than 14 days in situ. SAHA-DDP/PECE was subsequently injected into tumor OSCC tumor-beared mice. The results demonstrated that such a strategy as this allows the carrier system to show a sustained release of SAHA and DDP in vivo, and could improved therapeutic effects compared with a simple additive therapeutic effect of SAHA and DDP on mouse model. CONCLUSIONS: Our research indicated that the novel SAHA-DDP/PECE system based on biodegradable PECE copolymer enhanced the therapeutic effects and could diminished the side effects of SAHA/DDP. The present work might be of great importance to the further exploration of the potential application of SAHA/DDP-hydrogel controlled drug release system in the treatment of OSCC.

[Anatomic study of canal isthmuses of mandibular permanent incisors by micro-CT].

OBJECTIVE: To investigate the anatomic feature of the canal isthmus of mandibular permanent incisors by Micro-CT. METHODS: Thirty-three mandibular permanent incisors with two canals were selected through the radiograph in proximal view. These teeth were then scanned using Micro-CT and reconstructed. The scanning layer thickness was 20 microm. We observed the apical 6 mm of the 33 roots, and 300 sections were gained each tooth, giving a total of 9900 sections. The numbers of canals at each level in the apical 6 mm were recorded. The numbers of sections showing isthmuses at each level of the root canals were recorded too. Data were analyzed using the Chi-square statistic to test the null hypothesis that location of the sections in each of the apical 6 mm and presence of the isthmus were independent. The minimum root canal wall thickness was measured in each of the apical 6 mm of the roots. RESULTS: Isthmuses were found to be present at all levels with prevalence from 10.0% to 85.5%. The Chi-square test indicated a significant difference in the distribution of isthmuses with section (P = 0.0O1). The incidence of isthmuses was higher at the apical 3-6 mm level, and the highest incidence (85.5%) was at 5 mm level. There were many more sections containing complete isthmuses (49.7%) than those containing partial isthmuses (4.5%). The thickness of the minimum root canal was less than 0.5 mm. CONCLUSION: The mandibular incisors have a high incidence of isthmus and are narrow in proximal direction. Debridement of the isthmus is a major challenge during surgical and nonsurgical root canal treatment.

[Central mucoepidermoid carcinoma of the jaws: a clinical and pathological analysis of eight cases].

OBJECTIVE: To report eight cases of central mucoepidermoid carcinoma of the jaws (CMCJ) and to analyze its clinical and pathological features. METHODS: Eight cases of central mucoepidermoid carcinoma were diagnosed between 1989 and 2008. The clinical manifestation, radiological and histopathological changes were analyzed. RESULTS: The mean age of this group of patients was 43.3 years, with 5 male and 3 female. Seven cases occurred in mandible, mainly in the molar, angle and ramus areas, and one in maxilla. The first complain usually was local swelling, pain or paraesthesia of the jaw and loosening and pain of the tooth. X-ray displayed unilocular or multilocular radiolucent lesion with distinct or ill-distinct border, and the light microscopic findings were similar to the mucoepidermoid carcinoma originated in the salivary gland. CONCLUSIONS: To diagnose a CMCJ, it's necessary to synthetically analyze the case history, clinical examination, radiological and histopathological features. The treatment is wide local resection. Selective neck dissection and radiochemotherapy may improve curative effect and prognosis.

[Roles of matrix metalloproteinases and tissue specific inhibitors of metalloproteinases in dentinogenic ghost cell tumor and ghost cell odontogenic carcinoma].

OBJECTIVE: To investigate the roles of matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMP) in dentinogenic ghost cell tumor (DGCT) and ghost cell odontogenic carcinoma (GCOC). METHODS: The expressions of MMP-2, MMP-9, MMP-14, TIMP-1 and TIMP-2 were examined in 15 DGCT cases and 9 GCOC cases by immunohistochemistry. Their mRNA expression in one DGCT case and one GCOC case were investigated by RT-PCT.MMP-2 and MMP-9 protein activities in the two cases were analyzed by gelatin zymography. RESULTS: MMP-9 and TIMP-1 expressions elevated greatly in GCOC, and there was a significant difference (P < 0.05) in TIMP-1 expression between GCOC and DGCT.Pro-MMP-9, MMP-9 activated form, pro-MMP-2, and MMP-2 activated forms were detected in the GCOC case, while pro-MMP-9 and MMP-9 activated form were very faint in the DGCT case. The mRNA level of MMP-9 elevated obviously in the GCOC case, which was similar to that of TIMP-1. CONCLUSIONS: The elevated expression of MMP-9 and TIMP-1 may influence the behaviour of GCOC.