A unique biomaterial, DNA/atelocollagen membrane, was newly developed. The effect of DNA/atelocollagen combined with bovine derived-bone morphogenetic proteins (BMP) on osteogenesis was evaluated histologically in subcutaneous tissue and supra-alveolar and periodontal defects. DNA/atelocollagen was prepared as a composite of DNA from salmon milt and pepsin-digested type I collagen (atelocollagen) from bovine dermis. The composite fiber showed structural characteristics of DNA-coated atelocollagen on phase-contrast and fluorescence microscopy. The time-course of bone induction was investigated, using a rat ectopic bone formation assay. DNA/collagen (10×5×1mm) was subcutaneously implanted with 100μg of BMP induced osteoblast differentiation 1 week after operation. Histological examination of the BMP/DNA/collagen showed direct bone formation, and carrier DNA/collagen fibers were found in woven bone. Wounds through the supra-alveolar bone and periodontal ligament (10×5×5mm) were surgically created on the mesial root of the mandibular second and third premolars in 6 beagle dogs. The defects were immediately filled with either DNA/collagen (10×5×5mm) combined with 500μg of BMP or DNA/collagen alone, or were left unfilled (controls). Animals treated with BMP/DNA/collagen showed regeneration of alveolar bone, periodontal ligament, and cementum on the exposed dentin at 4 and 6 weeks, while the other groups showed virtually no regeneration. In addition, the newly formed bone and cementum were separated by a periodontal ligament-like tissue, and no ankylosis was seen. These results indicate that DNA/collagen is an effective absorbable material that can be used as a carrier matrix for BMP. DNA/collagen sponge combined with BMP may promote tissue regeneration without disturbing periodontal homeostasis in supra-alveolar and periodontal defects.
We used a combination of arthrocentesis, mouth opening exercises, and nansteroidal antiinflammatory drugs as a primary treatment for temporomandibular joint (TMJ) osteoarthrosis. This study evaluated the long-term results of this treatment by a mail questionnaire. Fifty patients with moderate and severe TMJ dysfunction who had TMJ unilateral osteoarthrosis were followed up from 1 year 6 months to 3 years 3 months (mean: 2 years 4 months) after the combined treatment. Of the 43 patients who returned the questionnaire, 37 (74%) had an acceptable outcome. Maximal mouth opening, pain on chewing, and pain on opening the mouth at the time of responding to the questionnaire were significantly better than those at time of finishing primary treatment. These results showed that stable effects were maintained after combined primary treatment.
Squamous cell carcinoma of the parotid gland is rare. Metastasis to the parotid gland occurs very rarely in oral carcinomas. This report describes a case of squamous cell carcinoma of the parotid gland with suspected metastasis from the maxillary alveolus. The patient was a 72-year-old woman who presented at the Department of Dentistry and Oral Surgery, Ishikawa Prefectural Central Hospital because of an ulcer in the right side of the maxillary gingiva. Clinical and radiographic examinations showed a lesion extending to the right side of the maxillary sinus. However, the parotid glands showed no evidence of the lesion. A biopsy was performed, and the histopathological diagnosis was squamous cell carcinoma. The tumor was resected after chemotherapy and radiation. A mass in the left parotid gland appeared 4 months after operation. Fine needle aspiration cytology was performed, and the histopathological diagnosis was squamous cell carcinoma. The mass was clinically diagnosed as a metastatic tumor and underwent resection. There was evidence of tumor recurrence 4 months after resection of the parotid gland tumor, and radiation therapy was performed. However, the patient died of pneumonia 1 and a half years after presentation to our department.
Stevens-Johnson's syndrome is a serious systemic disorder associated with vesicobullous lesions involving the skin and mucous membranes. We describe a rare case of Stevens-Johnson's syndrome showing initial symptoms in the oral cavity of a 27-year-old woman. Her chief complaint was tenderness because of erosive stomatitis. The results of blood tests indicated that this case was caused by herpes simplex. This case was successfully treated with steroids.
Neurilemmoma is a benign tumor derived from abnormal growth of Schwann cells. We report a case of a large neurilemmoma in the oral cavity. A 60-year-old man was referred to our department because of a tumor in the right side of the mouth floor. Clinically, the tongue was deviated to the left by the tumor, and magnetic resonance imaging showed a large oval mass. The clinical diagnosis was a benign tumor. The tumor was excised intraorally under general anesthesia. The excised specimen had a yellowbrownish surface, measured 65×42×35mm, and weighed 49 grams. The histopathological diagnosis was a neurilemmoma. The postoperative course of the patient has been good for 3 months.
Massive osteolysis is a rare disease characterized by continuous and progressive resorption of bone. We present a case of massive osteolysis of the mandible that responded to radiation therapy. A 47-year-old man was referred to our hospital because of progressive resorption of the mandible. On the basis of clinical and histological findings, he was given a diagnosis of massive osteolysis. He underwent radiotherapy with 40 Gy, and no bone resorption has occurred for 1 year 5 months after treatment.
Cheilitis granulomatosa (CG) is a chronic inflammatory disorder of unknown etiology. Various types of symptomatic therapy have been used to manage CG, with varying success. Recently, CG has been considered part of a new concept of disease referred to as “orofacial granulomatosis”. We report on a 40-year-old woman with persistent CG of the upper and lower lips that was successfully managed by local injection of dexamethasone. Treatment consisted of local injection of 4 mg dexamethasone diluted with lidocaine hydrochloride, administered at intervals of 1 to 4 weeks over the course of 7 months. After 5 months of treatment, both the upper and lower lips of the patient appeared normal. On follow-up at 1 year, the patient's lips remained normal in shape and contour.
Sialolithiasis is a common disease of the salivary glands that usually affects the submandibular gland. Histological changes, such as infiltration of inflammatory cells, atrophy or degeneration of acini, and fibrosis and metaplasia of ductal epithelium, are found in most cases, but fatty degeneration is rare. We report a case of sialolithiasis with severe fatty degeneration of the submandibular gland. In this case, fatty degeneration affected 70% of the submandibular gland. Moreover, fatty degeneration was found in each lobule and was not diffuse. The fatty degeneration was attributed to disturbed lipid metabolism related to anoxia, caused by local circulatory disorder related to severe inflammatory cell infiltration.
We encountered a case of secondary infection associated with a silicon implant in the mental region. A 41-year-old woman underwent plastic surgery with silicon implantation in the mental region 12 years previously. Recently, she had periapical periodontitis of the mandibular anterior teeth. She was cured by endodontic treatment by her dentist. Secondary infection of the silicon implant arose from the periapical periodontitis, and she was referred to our department. An abscess and an extraoral fistula were observed in the mental region. The silicon implant was removed surgically after resolution of infection. In the oral and maxillofacial region, silicon implants often cause secondary infection triggered by dental infection. This case suggests that oral hygiene and oral care are essential to prevent secondary infections derived from odontogenic infection.
Arthroscopic examination with an ultra-thin arthroscope is an easy, minimally invasive procedure for examination of the inside of joints. However, one disadvantage of arthroscopy is the risk of scope breakage in narrow joint spaces. We describe an improved procedure for arthroscopic examination of the upper joint space and describe the findings thus obtained. Arthroscopic examination is done with the patient under local anesthesia in the outpatient clinic. To observe the synovium in the posterior compartment, an 18-gauge needle and a trocar for a 0.8mm rod-lens fiberscope are inserted into the anterior and posterior compartments of the upper joint space, respectively. The articular cartilage of the glenoid fossa and eminence is also observed. Finally, the presence or absence of adhesion in the anterior compartment is examined. In narrowed joint spaces with severe adhesions, injection of normal saline under sufficient pressure is performed to widen the upper joint space. The fiberscope is then advanced from the posterior compartment to the anterior compartment via the lateral paradiscal groove. This procedure enables us to observe synovitis with capillary hyperemia or hyperplasia of the synovium, cartilage changes with fibrillation or exposure of subchondral bone, and the distribution and degree of adhesion.
We performed temporomandibular joint (TMJ) arthroscopic surgery to treat posterior disc displacement and obtained good results. The patient was a 58-year-old man who presented with masticatory disorders due to open bite in the molar region on October 3, 2001. The patient was given a diagnosis of posterior disc displacement in the right TMJ, and splint therapy and pumping manipulation were performed. Because the symptoms did not subside, the disc was arthroscopically repositioned on November 2. The postoperative clinical course has been good for 6 months, with no jaw movement disorders. Contact has been maintained between the upper and lower molars.