Vascularized autologous bone is considered the most suitable graft material for oral and maxillofacial bone defects. However, there are clinical limitations to the harvesting and shaping of grafts. The refore, several previous studies have evaluated prefabricated vascularized bone grafts. We have also experimentally studied prefabricated vascularized bone grafts using a non-biodegradable membrane (e-PTFE membrane). However, no membrane is needed when bone grafts are used. In this study, we made a biodegradable membrane and then prepared a vascularized bone graft with the membrane and autologous tissues. Combination of the biodegradable membrane with autologous tissue was found to be an effective means of making a bone graft with good ectopic blood circulation.
The objective of this study was to investigate the characteristics of osteogenesis around dental implants in both vascularized and nonvascularized bone grafts. Vascularized bone grafts were nourished by inferior alveolar vessels providing medullary blood flow to the mandibles of adult dogs. Titanium implants were placed into the bone grafts and normal mandibles. The time course of osteogenesis around the implants was observed histologically from 2 to 24 weeks after operation. Specimers stained with Stevenel's blue and Van Gieson-picrofuchsin stains and fluorescently labeled specimens were examined with a confocal laser scanning microscope. Implant-bone contact rates were determined. In vascularized bone grafts, new bone formation was evident all around the implants at 2 weeks postoperatively. New bone became compact with the passage of time. These processes of new bone formation were similar to those of normal mandibles. In cortical bone of vascularized bone grafts, bone resorption was recognized. However, bone remodeling was found at an early stage, suggesting that implants could be placed into vascularized bone grafts immediately after the primary operation. In nonvascularized bone grafts, bone resorption and remodeling occurred from the outside of cortical bone. New bone formation around implants was found at 8 weeks postoperatively. The implant apex was encapsulated by fibrous tissue at 24 weeks postoperatively. The results suggest that simultaneous implantation with free bone grafting requires a long time for bony linkage and that encapsulation of implants by fibrous tissue may occur in nonvascularized bone grafts.
We report a case of extranodal NK/T cell lymphoma, nasal type, which is a non-Hodgkin's lymphoma according to the new World Health Organization classification. A 69-year-old man was referred to our hospital because of a necrotizing ulcer on the right side of the maxillary gingiva. Computed tomography showed a soft tissue mass in the both paranasal sinuses, but no evidence of bone destruction. Histologic features included various inflammatory cells in the bottom of the ulcer. High fever, night sweat, and loss of body weight were noteds and the ulcer extended to both sides of the maxillary gingiva and palate. Ga and Tc scintillation scanning showed marked accumulation in the maxilla. Immunoohenotypic analysis of a biopsy specimen revealed that CD56 and Epstein-Barr virus encoded small RNA in situ hybridization (EBER ISH) were positive. The patient was given a diagnosis of extranodal NK/T cell lymphoma, nasal type, stage I E. The patient received chemotherapy with CHOP and radiotherapy. However, these therapies were not effective, and the patient died of lung metastasis.
A 73-year-old man presented to Tokai University Hospital because of a hemorrhagic facial mass. He had advanced hepatic cancer, diagnosed as cholangiocellular carcinoma (CCC), and was receiving palliative therapy. The tumor measured 43 × 45 × 80mm and had grown during the previous 2 months. A biopsy was performed, and the diagnosis was metastatic CCC. Hemorrhage from the metastatic tumor occurred frequently. Transarterial embolization therapy was performed, but control of hemostasis was poor. Complete hemostasis was obtained by surgical resection of the tumor. Postoperatively, the patient was able to intake food orally, and his quality of life improved. However, despite no recurrence of metastasis, he died of hepatic failure 2 months postoperatively. Autopsy revealed that most of the right lobe of the liver was replaced by CCC. Metastases were found in the left adrenal gland, lungs, and lymph nodes (liver hilus, para-aortic).
Osteoblastoma is a rare bone tumor associated with osteoid and atypical bone formation. We describe a case of osteoblastoma of the mandible in a 19-year-old woman. Radiographic examination of the tumor showed a well-defined radiopaque region, measuring approximately 13 mm in diameter and surrounded by a radiolucent area. The treatment was complete surgical excision. The postoperative course was uneventful. The osteoblastoma was mainly composed of abundant connective tissue showing active angiogenesis and osteoid bone covered with osteoblast-like cells and osteoclast-like multinuclear giant cells. We studied the tumor histologically and ultrastructually and examined tumor cell proliferation with MIB antibody immunohistologically.
A ganglion is a cyst-like lesion comprised of a fibrous capsule containing hyaluronic acid. In general, such lesions occur in the intramedullary juxtaarticular regions of the wrist, ankle, and knee joints. We report an extremely rare case of intraosseous ganglion of the condylar head. A 23-year-old woman was referred to our clinic on November 22, 1999 because of radiating pain around the right temporomandibular joint. She had no history of trauma. Pain increased on mouth opening and occlusion. The range of mouth opening was 33 mm between the upper and lower incisors. On computed tomography (CT), the surface of the right condylar head was flattened and partly defective; the bone marrow showed irregular resorption. The condition of the bone deteriorated on subsequent CTscans, and magnetic resonance images showed the lesion to be an irregular mass, measuring 0.8cm × 0.6cm with a clearly defined margin. Right condylectomy incloding the articular disc was performed to make a pathological diagnosis on October 25, 2000. Histopathologically, the condylar head contained cell-rich fibrous tissue associated with increased synovial tissue, including mucous changes, cystic changes, or both. The diagnosis was an intraosseous ganglion. As of 14 months postoperatively, there has been no recurrence or dysfunction.
This report describes a case of nodular fasciitis occurring in the oral floor of a 24-year-old man. He clained the swelling had gradually appeared 2 months previously, with no obvious cause. At initial examination, an elastic soft tumor the size of the forefinger-tip, was discovered under the normal oral floor mucosa. The tumor was removed surgically. It was not attached to the surrounding tissue and was able to be extirpated easily. The histopathological diagnosis was nodular fasciitis. Nodular fasciitis arising from intraoral tissue is rare, especially in the oral floor. Only 3 cases, including ours, have been reported in Japan.
An 83-year-old man was referred to our department because of severe facial pain on September 19, 2001. He had had continuous dull pain in the right cheek for 3 weeks and was prescribed antibiotics by an otolaryngologist 1 week before presentation. Despite treatment, progressive pain and swelling did not resolve. Physical examination revealed a tender, nonfluctuant swelling in the middle of the right side of the face and the submandibular and temporal regions. The patient had only 2 teeth in the upper right side of the maxilla. These teeth were slightly tender on percussion. The body temperature was 37.7°C. Blood tests revealed leukocytosis of 22700/μ1, a C-reactive protein level of 33.6mg/dl, and a glucose level of 142 mg/dl. Reexamination showed a free blood sugar level of 116 mg/dl and HbA 1 C of 5.2%. Computed tomography revealed extensive accumulation of gas bubbles in multiple spaces of the maxillofacial region. Intravenous administration of antibiotics was immediately initiated, and 3 incisions were made: 1 in the right side of the neck and 2 in the temporal region. A large amount of foul-smelling purulent material was drained. Gram-stain smears indicated mixed infection with gram-positive cocci and gram-negative rods. The culture revealed the presence of Staphylococcus and Fusobactenum, but not Clostridium. On the basis of these findings, a final diagnosis of non-clostridial gas gangrene was made.