Targeting the sonic hedgehog pathway in keratocystic odontogenic tumor.

Keratocystic odontogenic tumors (KCOT) may occur sporadically or associated with the nevoid basal cell carcinoma syndrome. It is a benign aggressive tumor of odontogenic epithelial origin with a high rate of recurrence. A primary human keratocystic odontogenic tumor cell population, KCOT-1, has been established from a tumor explant culture. The KCOT-1 cells were characterized by growth rate, gene expression profiles of major tooth enamel matrix proteins (EMPs), amelogenin (AMELX), enamelin (ENAM), ameloblastin (AMBN), amelotin (AMTN), tumor-related proteins enamelysin (MMP-20), kallikrein-4 (KLK-4), and odontogenic ameloblast-associated protein (ODAM) using quantitative real-time reverse transcription-polymerase chain reaction. Cytokeratin 14 (CK14) was examined by immunohistochemistry. In addition, expression of the members of the sonic hedgehog (SHH) pathway, SHH, patched (PTCH-1), smoothened (SMO), GLI-1, and GLI-2 and of the NOTCH signaling pathway, NOTCH-1, NOTCH-2, NOTCH-3, JAG-2 (Jagged-2), and Delta-like-1 (DLL-1) were evaluated. KCOT-1 cells were treated with SMO antagonist cyclopamine. We found that cyclopamine significantly arrested the growth of KCOT-1 cells in a dose-dependent manner and that the effects of cyclopamine were abolished by adding SHH protein. The protein expression of the SHH pathway was down-regulated by cyclopamine, further confirming that cyclopamine inhibits the SHH signaling pathway; SHH down-regulation correlated with the down-regulation of the NOTCH signaling pathway as well. In conclusion, using an established KCOT-1 cell population, we characterized the gene expression profiles related to the EMPs, SHH, and NOTCH signaling pathway and confirmed that cyclopamine significantly arrested the growth of KCOT-1 cells and may be a viable agent as a novel therapeutic.

How can we diagnose and treat osteomyelitis of the jaws as early as possible?

Osteomyelitis of the jaws is an uncommon infection of the maxillofacial area. The disease is often difficult to diagnose, and thus delays in treatment are common, increasing its morbidity. The clinical, radiographic, and laboratory findings of the disease; its forms; and treatment modalities are reviewed. Suggestions for contemporary diagnosis and surgical treatment of acute and chronic suppurative osteomyelitis are discussed.

The use of demineralized bone matrix for grafting during Le Fort I and chin osteotomies: techniques and complications.

PURPOSE: To examine the use of demineralized bone matrix (DBM) in maxillary and chin orthognathic surgery. The use of DBM in orthognathic surgery has not been reported in the literature. PATIENTS AND METHODS: A retrospective review of the orthognathic surgeries performed in 1 university was conducted. Medical records were assessed to determine the materials used, complications, and details of re-operations required. RESULTS: There were 113 suitable patients identified. The DBM group (88 patients) consisted of 61 Le Fort I osteotomies and 46 genioplasties; the non-DBM group (25 patients) consisted of 25 Le Fort I osteotomies and 4 genioplasties. The mean follow-up period was 5.9 months for the DBM group and 6 months for the non-DBM group. There was only 1 technique of applying DBM to genioplasties, but a variety of different graft material combinations was used in the Le Fort I osteotomies. The only significant Le Fort I complication was maxillary sinusitis; its incidence was 3.3% (2 out of 61) for the DBM group, versus 8% (2 out of 25) in the non-DBM group. All the genioplasties had no complications. There were 4 cases of Le Fort I osteotomies which were re-entered (2 cases for suspected infection and 2 cases for re-osteotomies due to occlusal malalignment) and they showed good bony healing. CONCLUSION: The use of DBM does not significantly increase complications and is suitable to be used in both the maxilla and chin during orthognathic surgery.