Hyun-Young Cho

Odontogenic carcinosarcoma of the mandible: a case report and review.

Odontogenic carcinosarcoma is an extremely rare malignant odontogenic tumor with only a few reported cases. It is characterized by a true mixed tumor showing malignant cytology of both epithelial and mesenchymal components. It has been assumed to arise from pre-existing lesions such as ameloblastoma, ameloblastic fibroma, and ameloblastic fibrosarcoma. To date, the reported cases have exhibited considerably aggressive clinical behavior. The case of an odontogenic carcinosarcoma in the mandible of a 61-year-old male is described herein. The tumor destroyed the cortex of the mandible and invaded the adjacent tissues. Treatment was performed by surgical resection and reconstruction. The purposes of this article are to introduce odontogenic carcinosarcoma through this case study, to distinguish it from related diseases and to discuss features of the tumor in the existing literature.

Tibial bone fractures occurring after medioproximal tibial bone grafts for oral and maxillofacial reconstruction

Objectives Oral and maxillofacial defects often require bone grafts to restore missing tissues. Well-recognized donor sites include the anterior and posterior iliac crest, rib, and intercalvarial diploic bone. The proximal tibia has also been explored as an alternative donor site. The use of the tibia for bone graft has many benefits, such as procedural ease, adequate volume of cancellous and cortical bone, and minimal complications. Although patients rarely complain of pain, swelling, discomfort, or dysfunction, such as gait disturbance, both patients and surgeons should pay close attention to such after effects due to the possibility of tibial fracture. The purpose of this study is to analyze tibial fractures that occurring after osteotomy for a medioproximal tibial graft. Materials and Methods An analysis was intended for patients who underwent medioproximal tibial graft between March 2004 and December 2011 in Inha University Hospital. A total of 105 subjects, 30 females and 75 males, ranged in age from 17 to 78 years. We investigated the age, weight, circumstance, and graft timing in relation to tibial fracture. Results Tibial fractures occurred in four of 105 patients. There were no significant differences in graft region, shape, or scale between the fractured and non-fractured patients. Conclusion Patients who undergo tibial grafts must be careful of excessive external force after the operation.

Facelift incision and superficial musculoaponeurotic system advancement in parotidectomy: case reports

Surgical procedures for parotidectomy had been developed to gain adequate approach, prevent morbidity of nerve, and give esthetic satisfaction.We performed two cases of parotidectomy through facelift incision. One case was reconstructed with superficial musculoaponeurotic system (SMAS) flap and sternocleidomastoid (SCM) muscle rotated flap at the parotid bed. In second case, same procedures were performed, but collagen membrane was additionally implanted for prevention of Frey’s syndrome. After surgery, two cases showed esthetic results without neck scar and hollow defect on parotid bed area.

Pigmented villonodular synovitis of the temporomandibular joint - computed tomography and magnetic resonance findings: a case report

Pigmented villonodular synovitis (PVNS) is a benign but locally aggressive and destructive disease originating in the synovial membranes. It is a proliferative disorder of unknown etiology. Involvement of the temporomandibular joint (TMJ) is very rare. Computed tomography clearly reveals areas of lytic bone erosion and sclerosis, and also clearly defines the extent of the tumor which is the focal areas of hyperdensity within the soft-tissue mass. Magnetic resonance images invariably show profound hypointensity on both T1- and T2-weighted sequences due to hemosiderin pigmentation. Additionally, high signal intensity on T2-weighted images may indicate cystic loculation of the joint fluid. This case study describes a rare case of PVNS of the TMJ with bone destruction of the mandibular condyle. Complete surgical excision of the lesion was performed through a preauricular approach with temporal extension. During the 10-year follow-up, two more operations were performed due to local recurrence and the fracture of the reconstruction plate. Total joint reconstruction with Biomet was finally performed, and the absence of disease was confirmed with a biopsy report showing fibrosis with hyalinization and mild inflammation of the excised soft tissue from the old lesion.

Effect of herbal extracts on bone regeneration in a rat calvaria defect model and screening system

Objectives The aim of this study was to evaluate the effects of herbal extracts on bone regeneration. Two known samples were screened. Materials and Methods We previously established a rat calvaria defect model using a combination of collagen scaffold and herbal extracts. An 8 mm diameter trephine bur with a low-speed dental hand piece was used to create a circular calvaria defect. The experimental group was divided into 4 classifications: control, collagen matrix, Danshen with collagen, and Ge Gan with collagen. Animals in each group were sacrificed at 4, 6, 8, and 10 weeks after surgery, and bone regeneration ability was evaluated by histological examination. Results Results revealed that both Danshen and Ge Gan extracts increased bone formation activity when used with collagen matrix. All groups showed almost the same histological findings until 6 weeks. However, after 6 weeks, bone formation activity proceeded differently in each group. In the experimental groups, new bone formation activity was found continuously up to 10 weeks. In the Danshen and Ge Gan groups, grafted materials were still present until 10 weeks after treatment, as evidenced by foreign body reactions showing multinucleated giant cells in chronic inflammatory vascular connective tissue. Conclusion Histological analyses showed that Danshen and Ge Gan extractions increased bone formation activity when used in conjunction with collagen matrix.

Intracorporeal reduction of condylar fracture using both pedicled condylar and seperated ramal fragments after vertical ramal osteotomy

The aim of this study is to introduce a surgical technique that can maintain blood supply to prevent condylar resorption in the extracorporeal reduction of condylar fracture. Neither the medial pterygoid muscle on the ramal bone nor the lateral pterygoid muscle on the condylar fragment was detached after vertical ramal osteotomy. Thus, reduction was performed in the intracorporeal state. Therefore, blood supply was expected to be maintained to the fragments of both the condylar and ramal bones. On postoperative radiographs, the anatomical outline of the fractured condyle was well restored, and the occlusion was stable. In the unilateral case, there were no signs of mandibular condylar resorption until postoperative 3 weeks. In the 2 bilateral cases, condylar displacements with plate fractures and screw loosening were observed at postoperative 1 month or 5 months, but radiodensity at the displaced fracture site increased during the follow-up period. Finally, complete remodeling of the condylar fragments with restored anatomic appearance was observed on 8-month or 2-year follow-up radiographs. All cases exhibited good healing aspects with no signs or symptoms of mandibular condylar dysfunction during the postoperative remodeling period after intracorporeal reduction of condylar fracture.

Prostate adenocarcinoma mandibular metastasis associated with numb chin syndrome: a case report

The purpose of this study is to report a rare case of mandibular adenocarcinoma that was diagnosed due to metastasis from the prostate. Numb chin syndrome (NCS), which was associated with this case, is also discussed. Computed tomography (CT) and an intraoral incisional biopsy of the left mandibular area were performed. Urology consultation, hormone therapy, chemotherapy and follow-up radiographic images were administered. Histological examination of the incised specimen revealed moderately differentiated adenocarcinoma. The Gleason score was 8 (primary 4/secondary 4). Immunohistochemical features and radiographic results confirmed the diagnosis of metastasis from prostate adenocarcinoma, moderately differentiated. The patients prostate-specific antigen (PSA) level was very high. After hormone treatment, the patients PSA levels dropped gradually. Seventeen months later, in May 2015, the PSA level was elevated. The 18-month follow-up CT image indicated that the patients condition was aggravated. Docetaxel chemotherapy was started in June 2015 (18 months later), and the sixth cycle of the therapy is in progress. Oral metastases that originate from prostate adenocarcinoma are rare and can induce various periosteal reactions. Hormone therapy, chemotherapy and close follow-up could be additional, appropriate treatment, and were applied in this case. Finally, NCS is a valuable indicator of metastatic disease in the mandible.