Clinical evaluation of fenestration decompression combined with secondary curettage for ameloblastoma of the jaw: retrospective radiographic analysis.

BACKGROUND: Ameloblastoma is a benign odontogenic epithelial tumor with local infiltration and a high recurrence rate that occurs most frequently in the jawbone. The aim of this study was to investigate the outcomes of fenestration decompression combined with secondary curettage (FDSC) in the surgical treatment of jaw ameloblastoma, and clarify the possibility of FDSC to become an appropriate therapeutic method for ameloblastoma with large lesion. METHODS: A retrospective analysis was carried out in 145 patients diagnosed with multicystic ameloblastoma (MA) and 88 patients with unicystic ameloblastoma (UA). These patients were divided into two groups based on the therapeutic regimen: the FDSC group and the local curettage (LC) group. Panoramic radiography was taken 2 years after curettage to evaluate the change in lesion area in each case, and the therapeutic effects of different treatment methods were further assessed by the chi square test. RESULTS: For MA, the effective rate of cystic cavity area reduction in the FDSC group (71.19%) was higher than that in the LC group (30.23%) (P < 0.001). For UA patients, the effective rate of lesion area reduction after FDSC was 93.02%, which was higher than that after LC (53.33%) (P < 0.001). Moreover, the recurrence rate of the FDSC group in the MA was 30.51%, which was significantly different from that of the LC group (P < 0.001). Regarding UA, the recurrence rates were 13.95% and 28.89%, after FDSC and LC, respectively, with no significant differences between the two groups (P > 0.05). CONCLUSIONS: FDSC exhibits a much better curative effect than LC in both MA and UA, whereas the recurrence rate of these two therapeutic strategies did not significantly differ in UA. The above data demonstrated that FDSC may serve as a routine, safe, effective and appropriate surgical treatment plan for MA or UA patients with large lesions.

Zoledronate inhibits the differentiation potential of adipose-derived stem cells into osteoblasts in repairing jaw necrosis.

OBJECTIVE: To explore the inhibitory effects of zoledronate (ZOL) on adipose-derived stem cells (ADSCs) into osteoblasts for repairing jaw necrosis. METHODS: ADSCs were induced to differentiate into osteoblasts. The differentiation characteristics of osteoblasts was observed under inverted microscope by alizarin red staining. The transwell assay was performed to evaluate the migration of ADSCs co-cultured with osteoblasts and divided into ZOL group treated with ZOL and N-ZOL group without ZOL treatment. The differentiation and proliferation characteristics of ADSCs differentiated osteoblasts were observed respectively. The expression of CTSK (Cathepsin K) and FGFR3 (Fibroblast growth factor receptor 3) in osteoblasts were analyzed by immunofluorescence and western blot. RESULTS: The differentiation degree and proliferation of ADSCs to osteoblasts in N-ZOL group were both higher than those in ZOL group. The migratory cell number in ADSCs differentiation in ZOL group was higher than that of N-ZOL group. The protein expression of CTSK and FGFR3 in ADSCs differentiated to osteoblasts in ZOL group was higher than that in N-ZOL group. CONCLUSION: The differentiation of ADSCs into osteoblasts is significantly inhibited by ZOL. Due to this reason, it may be difficult to achieve good results by ZOL induced ADSCs into osteoblasts in repairing jaw necrosis.

[Treatment of maxillary ameloblastoma with different modalities: a retrospective analysis of 92 cases].

PURPOSE: To explore the appropriate surgical approach for each type of maxillary ameloblastoma. METHODS: The clinical data of 92 patients with maxillary ameloblastoma were retrospectively analyzed. All patients were pathologically diagnosed, followed up for 3-8 years after surgery, maxillofacial CT and panoramic images were taken regularly to observe the surgical outcomes. SPSS 22.0 software package was used for data analysis. RESULTS: The proportion of maxillary ameloblastoma in male and female patients was 3 to 1,with more male patients and the mean age was 45.77 years old. The total recurrence rate of 92 patients was 21.74%, among which unicystic ameloblastoma had no recurrence after different surgical procedures. Among 38 patients with typical maxillary ameloblastoma, 14 underwent curettage, 3 underwent decompression，16 underwent extended resection, 3 underwent subtotal maxillary resection, 1 underwent iliac bone transplantation after subtotal maxillary resection, and 1 underwent reconstruction with anterolateral thigh flap after subtotal maxillary resection. Among them, 18 had recurrence and 5 had canceration. Three patients with extrasseous/peripheral type underwent expanded resection and two underwent curettage，none of them had recurrence. One patient with metastasizing ameloblastoma recurred after extended resection. CONCLUSIONS: Maxillary ameloblastoma with unicystic type should be completely removed with minimal trauma. The recurrence rate of maxillary ameloblastoma via simple curettage or extended resection is still relatively high, which may be due to the large tumor involvement scope of these patients and the failure of complete tumor removal by curettage. For external/peripheral ameloblastoma and metastatic ameloblastoma, the involved jaw bone should be removed as much as possible to prevent recurrence. For malignant transformation of ameloblastoma, the tumor and jaw bone should be dissected during the operation to reduce recurrence rate. The primary site, cervical lymph nodes and lungs should be closely followed after operation to detect early metastasis.

Second primary oral squamous cell carcinoma after radiotherapy: a retrospective cohort study.

BACKGROUND: The purpose of the present study was to investigate the clinicopathological characteristics and prognostic factors of second primary oral squamous cell carcinoma after radiotherapy for head and neck cancer. METHODS: The clinicopathological characteristics of 48 second primary oral squamous cell carcinoma patients with a history of radiotherapy for head and neck cancer were retrospectively analyzed by Kaplan-Meier survival analysis and Cox proportional hazards model, including gender, age, alcohol consumption, smoking, clinical stage, margin status, regional lymph node status, tumor differentiation and treatment mode. RESULTS: The second primary oral squamous cell carcinoma mostly occurred on the tongue [18/48], buccal [12/48] and gingiva [10/48], and the 3- and 5-year overall survival (OS) was 60.3% and 39.4%, respectively. Margin status and extranodal extension were significantly associated with OS, while only margin status was found to be an independent prognostic factor of OS in the Cox proportional hazards model (P=0.003, HR =3.976, 95% CI: 1.596-9.904). CONCLUSIONS: Oral squamous cell carcinoma patients underwent radiotherapy for head and neck cancer show poor survival outcomes. Margin status is an independent prognostic factor of second primary oral squamous cell carcinoma.