microRNAs (miRNAs) are involved in cancer pathogenesis, apoptosis and cell growth, thereby functioning as both tumor suppressors and oncogenes. However, the expression patterns and roles of miRNAs in oral squamous cell carcinoma (OSCC) remain largely unknown. We hypothesized that oral cancer may have a unique miRNA profile, which in turn may play a critical role in oral cancer development, progression, diagnosis and prognosis. We, therefore, investigated the expression profiles of 29 OSCC tumors and 7 normal oral mucosal samples. The miRNA expression patterns in OSCC were examined by TaqMan-based microRNA assays. We were subsequently able to identify the candidates of cancer-related miRNAs through analysis of the miRNA expression profiles. In conclusion, OSCC tissues were shown to have a unique miRNA profile pattern when compared with that in normal tissues. The present study may provide useful information for further investigation of the functional roles of miRNAs in OSCC development, progression, diagnosis and prognosis.

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The osteogenic induction of adipose-derived stem cells (ADSCs) has been regarded as an important step in bone tissue engineering. In the present study, we focused on the buccal fat pad (BFP) as a source of adipose tissue, since BFPs are encapsulated by adipose tissue and are often coextirpated during oral surgery. Low-intensity pulsed ultrasound (LIPUS) is effective in the treatment of fractures, and nanohydroxyapatite (NHA) is known as a bone substitute material. Here we investigated the synergistic effects of LIPUS and NHA in the osteogenesis of ADSCs. A combination of LIPUS irritation and NHA as a scaffold significantly increased the osteogenic differentiation of ADSCs in vitro, and in our in vivo study in which ADSCs were transplanted into calvarial bone defects of nude mice, the combinational effect greatly enhanced the new bone formation of the margin of the defects. These results demonstrate that synergistic effects of LIPUS and NHA are capable of effectively inducing the differentiation of ADSCs into osteoblasts, and they suggest a novel therapeutic strategy for bone regeneration by the autotransplantation of ADSCs.

Odontogenic myxoma (OM) is a relatively rare, benign odontogenic tumor with locally aggressive behavior, but it is a nonmetastasizing neoplasm of the jaw bones. Although radical resection with an appropriate surgical margin is recommended, emerging evidence has suggested that a more conservative approach will result in acceptable recurrence rates with less morbidity if careful long-term follow-up is provided. A 56-year-old Japanese man with odontogenic myxoma of the left mandible was conservatively treated by surgical enucleation and curettage because he desired functional and cosmetic preservation. During a follow-up period of 100 months, the patient has remained clinically and radiologically free of recurrence. As far as we can ascertain, 20 reports published after 1990 described 37 patients with mandibular OM that had been treated by conservative surgery. Tumors recurred during a mean follow-up of 49.2±42.8 months in 7 (18.9%) patients, and only one of five patients who were followed up for over 100 months developed recurrence. The rate of recurrence decreased from 24.0% to 8.3% when follow-up exceeded 60 months. Although enucleation and curettage have proven effective, the risk of recurrence remains considerable and long-term follow-up is indispensable. More evidence of long-term outcomes after conservative surgery for OM is needed.

Purpose To evaluate the accuracy of the maxillary segment positioning method using a splint fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM) and surgical navigation in patients who required two-jaw surgery. Methods Subjects were 35 patients requiring two-jaw surgery. A 3-dimensional (3D) skull model was prepared using cone-beam computed tomography (CBCT) data and dentition model scan data. Two-jaw surgery was simulated using this model, and a splint for maxillary positioning was fabricated by CAD/CAM. Using coordinate transformation software, the coordinate axis of surgical simulation data was merged with the navigation system, and data were imported to the navigation system. The maxillary segment was placed using the CAD/CAM splint, and consistency of the maxillary segment position with that planned by simulation was confirmed using the navigation system. CBCT taken at 4 weeks postoperatively and the prediction image fabricated using surgical simulation were superimposed. Predicted movement distances (PMD) at 6 arbitrary measurement points and actual movement distance (AMD) in surgery were measured. Differences of 3D measurements between the surgical simulation and postoperative results were evaluated. Results No significant differences were seen between PMD and AMD at most measurement points on the X and Y axes. Although significant differences between PMD and AMD were seen on the Z axis, no difference was evident between linear distance on the estimated image and postoperative CBCT image at most measurement points in 3D space. Mean error at measurement points between the PMD and AMD ranged from 0.57 mm to 0.78 mm on the X axis, 0.64 mm–1.03 mm on the Y axis, and 0.84 mm–0.90 mm in the Z axis. Conclusion Position of the maxillary segment moved by the CAD/CAM splint in Le Fort I osteotomy was almost consistent with the position established by simulation using the navigation system, confirming clinical accuracy.