No abstract available.

No abstract available.
Adenoma, Pleomorphic ; Mouth Mucosa

No abstract available.

No abstract available.
Carcinoma, Verrucous ; Lip

Adult ; Connective Tissue ; Extremities ; Head ; Histiocytoma, Malignant Fibrous ; Humans ; Maxilla ; Neck ; Radiotherapy ; Sarcoma

Retinal prostheses are being developed to restore vision for the blind with retinal diseases such as retinitis pigmentosa (RP) or age-related macular degeneration (AMD). Since retinal prostheses depend upon electrical stimulation to control neural activity, optimal stimulation parameters for successful encoding of visual information are one of the most important requirements to enable visual perception. Therefore, in this paper, we focused on retinal ganglion cell (RGC) responses to different voltage stimulation parameters and compared threshold charge densities in normal and rd1 mice. For this purpose, we used in vitro preparation for the retina of normal and rd1 mice on micro-electrode arrays. When the neural network of rd1 mouse retinas is stimulated with voltage-controlled pulses, RGCs in degenerated retina also respond to voltage amplitude or voltage duration modulation as well in wild-type RGCs. But the temporal pattern of RGCs response is very different; in wild-type RGCs, single peak within 100 ms appears while in RGCs in degenerated retina multiple peaks (~4 peaks) with ~10 Hz rhythm within 400 ms appear. The thresholds for electrical activation of RGCs are overall more elevated in rd1 mouse retinas compared to wild-type mouse retinas: The thresholds for activation of RGCs in rd1 mouse retinas were on average two times higher (70.50~99.87micronC/cm2 vs. 37.23~61.65micronC/cm2) in the experiment of voltage amplitude modulation and five times higher (120.5~170.6micronC/cm2 vs. 22.69~37.57micronC/cm2) in the experiment of voltage duration modulation than those in wild-type mouse retinas. This is compatible with the findings from human studies that the currents required for evoking visual percepts in RP patients is much higher than those needed in healthy individuals. These results will be used as a guideline for optimal stimulation parameters for upcoming Korean-type retinal prosthesis.
Animals ; Electric Stimulation ; Fees and Charges ; Humans ; Macular Degeneration ; Mice ; Retina ; Retinal Diseases ; Retinal Ganglion Cells ; Retinaldehyde ; Retinitis Pigmentosa ; Vision, Ocular ; Visual Perception ; Visual Prosthesis

Carcinomas derived from ameloblastomas have been designated by a variety of terms, including malignant ameloblastoma, ameloblastic carcinoma, metastatic ameloblastoma, and primary intra-alveolar epidermoid carcinoma. The term of ameloblastic carcinoma is differentiated from the term of malignant amelblastoma and is defined as an ameloblastoma in which there is histologic evidence of malignancy in the primary tumor or the recurrent tumor(or metastasis), regardless of whether it has metastasized. The well-documented and adequately followed cases are currently lacking and this report described an instance of ameloblastic carcinoma with good result after treatment and review of literature.
Ameloblastoma ; Ameloblasts* ; Carcinoma, Squamous Cell ; Mandible*

This is a case report and review of literature of a rare mixed odontogenic tumor, ameloblastic fibro-odontoma in the posterior area of the mandible. The ameloblastic fibro-odontoma which was developed by hyperplasia of dental epithelium and mesenchymal tissue. This tumor was classified from ameloblastic odontoma by Hooker, in 1967. At first and characterized by mixed appearance of odontoma and ameloblastic fibro-odontoma, But, on the point of pathologic feature, there are many controversial opinions among scholars up to the present. The patients of this case report was refereed to our department via the pedodontic department for the treatment of hard mass on the premolar area of the left mandible. And then, on the clinical and radiographic examination at first visit, we had tentative diagnosis that the lesion was benign mixed odontogenic tumor of defined mass margin that was amelblastic fibro-odontoma. The tumor mass was removed by surgical enucleation and curettage and extracted left mandibular second premolar which was impacted on the lesion. And the removed tumor mass was confirmed to ameloblastic fibro-odontoma on the post-operative biopsy. The patients has well done follow-up check postoperatively and shown no sign of recurrence up to the present.
Ameloblasts* ; Bicuspid ; Biopsy ; Curettage ; Diagnosis ; Epithelium ; Follow-Up Studies ; Humans ; Hyperplasia ; Mandible* ; Odontogenic Tumors ; Odontoma ; Recurrence

Maxillofacial infection often place the oral and maxillofacial surgeon in situations where timely decisions have to be made. These decisions can be lifesaving. Odontogenic infection are frequently encountered in the practice of oral and maxillofacial surgery. These infections often repond to surgical and antimicrobial management. Otheriwise odontogenic infections have the potential to spread via the fasical spaces in the head and neck region. They can compromise vital structures in this region or involve distant structures. The classic signs of maxillofacial infections include pain, swelling, fever, dysphagia, and dehydration. The goals of management should be to correct these conditions. We have undertaken clinical studies on infections in the oral and maxillofacial regions (facial space) by analyzing hospitalized patients in the Dept. of Oral and Maxillofacial Surgery, Kyung Hee University Hospital past 5 years from 1991. To 1995. And bacterial cultures and antibiotics sensitivity test were performed and the comparative analysis of the antibiotics was done. The results were as follows: 1. The most frequent cause of oral and maxillofacial infection was odontogenic 68% and in 23% patients with signs and symptom aggrevated after teeth extraction. 2. The most common fascial spaces involved was buccal space 36.1%, followed by submandibular space 12.3% and 3 cases were Ludwig's angina. 3. Antibiotics were administrated in all cases and surgical incision and drainage was performed in 88.6%. 4. The most causative organisms isolated from the pus cultures were streptococci group 51.1%.
Anti-Bacterial Agents ; Deglutition Disorders ; Dehydration ; Drainage ; Fever ; Head ; Humans ; Ludwig's Angina ; Neck ; Suppuration ; Surgery, Oral ; Tooth

Nd:YAG laser is well absorbed to water, melanin, hemoglobin and thus, Nd:YAG laser may be used for bleeding control and extraction site sterilization where is easily contaminated by saliva and blood. Additionaly, Nd:YAG laser have analgesic effect by elevation of pain threshold. On the basis of Nd:YAG laser effects, we applied the Nd:YAG laser on extraction socket of 50 patients who visited to our department for lower third molar extraction and evaluated the effects of Nd:YAG laser on the bleeding control, pain relief, swelling reduction after tooth extraction. For the objective assesment on Nd:YAG laser effects, we made up the other 50 patients(control group) who were treated by conventional extraction method and compare the subjective and objective symptoms(pain relief, swelling and oozing time) between each group. The results were as follows: 1. The Nd:YAG laser was effective to relief of postextraction pain and most effective to 2 hours after extraction when local anesthesia disappears. 2. The Nd:YAG laser application was non-effective to reducing the facial swelling after extraction. 3. The Nd:YAG was effective to decrease the oozing time after extraction and the average time was 4 hours.
Anesthesia, Local ; Equidae ; Hemorrhage ; Humans ; Lasers, Solid-State* ; Melanins ; Molar, Third ; Pain Threshold ; Saliva ; Sterilization ; Tooth Extraction