To analyze articulatory movement trajectories and sound production simultaneously, a motion analyzer, which consisted of a high-speed video system, an image processor and a sound spectrograph, was specifically created.
The measurement error of the head mobility correction system and the reference markers trajectories were studied. Utilizing this new system, articulatory jaw movement during the production of /t/ sounds was then observed in a glossectomy patient who had had reconstructive surgery done with the fore-arm flap, as well as a normal adult.
The results follow :
1. Via the head mobility correction program, the new system has been proved to be adequately successful in correcting the head's mobility during speech production.
2. As the measurement error of reference markers trajectories was extremely small, the reliability of this new system was confirmed.
3. The glossectomy patient exhibited higher mandibular position and abnormal mandibular movement than normal adults during /ata/ production.
In conclusion, this new system is considered to be useful for observing mandibular movement articulation in a glossectomy patient, who has had reconstructive surgery, during speech production.

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Morphological changes in caries-affected or caries-free dentin during experimental dentin bonding procedures were observed using a SEM. The cavity wall was conditioned with 0.5 mol/l EDTA; next, the cavity was primed with or without GM solution; a commercial dentin bonding agent (Clearfil Photo Bond) was applied, followed by a commercial resin composite (Silux Plus) to restore the cavity. The dentin tubules of the caries-affected dentin were filled with the rod-shaped substances or the cubic crystals of the Whitlockite which interfere with the penetration of the dentin bonding agent. A short and donut-shaped resin tag was formed in the sclerotic dentin though the resin tag was long and tough in the caries-free dentin. However, no obvious change was recognized in the interfacial microstructure by GM priming in both the caries-affected or the caries-free dentin. It was possible to conclude that the adhesive monomer infiltration into the sclerotic dentin was interrupted by GM priming although monomer diffusion into the dentin or resin tag formation of the caries-affected dentin scarcely affected the bonding between the resin composite and the dentin.

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The relationship between lateral deviation of the spine and occlusion is currently the subject of considerable research in the field of odontology. When an afflicted individual begins to feel symptoms in the head, neck and shoulder region, lateral deviation of the spine is larger than in a healthy person. Many muscles are working to stabilize the head position orientation. Some researchers have found that unilateral occlusion may influence tension in the trapezius and sternocleidomastoid muscles. Muscular tension has also been proposed as a likely cause of lateral deviation of the spine. Although a number of studies have investigated the relationship between occlusion and lateral deviation of the spine, little is known about the influence of tension.
The present paper attempts to explain the relationship between occlusion and lateral deviation of the spine through active simulation using a computer. Analysis was carried out using the 3-dimensional analysis software package “MADYMO”. When unilateral tension was applied to either the trapezius muscle or sternocleidomastoid muscle, the head was deviated to the operated side. At the same time, the cervical spine and lumbar spine were deviated to the opposite side, whereas the thoracic spine was deviated to the operated side. The same results were observed when tension was applied to both muscles. Based on the above results, unilateral tension on cervical muscles has a strong effect on development of the spinal curve. Moreover, unilateral occlusion likely influences lateral deviation of the spine.

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The aim of this study was to investigate the effects of rhBMP-2 on wound healing of the bone where long-term effects of irradiation had developed. Forty male Wistar rats were used. A single dose of 15 or 30 Gy irradiation from a Linac source was delivered to the right lower leg of all rats. The left leg was remained as non-irradiated site. A block of Poly D, L-lactic-co-glycolic acid (PLGA) and gelatin sponge with 100 ng, 1, or 2μg rhBMP-2 was installed to the bilateral tibial proximal metaphysis three months after irradiation. The rats implanted the carrier without rhBMP-2 were served as control. Two weeks after placement, the bone healing was examined histologically. The newly formed bone mineral content (BMC) was also quantified with pQCT. The results obtained were as follows :
1. Administration of rhBMP-2 promoted bone formation in both the 15 and 30 Gy irradiated groups.
2. However, BMC did not increase dose-dependently in either irradiated group, but did in the non-irradiated control.
3. Bone formation in the central and outer parts of the carrier was less in the 30-Gy group than the control and the 15 Gy group.
These results indicate that rhBMP-2 improves bone formation to some degree in bone where long-term effects of irradiation had developed, but the level was not so high as on the nonirradiated bone.

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By the development of the technology of the tissue engineering, the research on tissue regeneration using the transplantation of the cultured tissue would be carried out in great numbers introduction recent years. However, the transplantation of culture cell to in vivo the graft cell proliferates in vivo in order to use the cell which is similar to the transplantation field, and there are many unclear point on the retrieval of differentiating. Then, the green fluorescence protein (GFP) of Jellyfish Aequorea Victoria was genetically transfected into the culture periodontal ligament cell in order to examine, and it was made to be the cell marker. By transplanting this periodontal ligament cell with gene transfection in the bone, and observing the dynamic phase of graft cell time-dependent, the growth and differentiation of the cells in the transplantation field were morphologically examined. The periodontal ligament cells were cultivated three-dimensional in the collagen gel in respect of the GFP gene in periodontal ligament culture cells that it extracted from maxilla incisor root part of tooth of the Wistar strains rat and collected. The periodontal ligament cell inclusion gel was transplanted in the rat skull. The new bone formation did not recognize large difference, when GFP gene transfected cells and non-GFP gene introduction cells were transplanted. And, the GFP gene transfected cells group recognized the fluorescent coloring in the cell in which period in the session length. It was indicated to become a marker, when the transfection of the GFP gene to graft cell from the fact observes the dynamic phase of graft cell.

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A competitive ELISA method was constructed for measurement of the salivary level of lactoferrin. The salivary lactoferrin level obtaind by this method was 7.72±3.74 μg/ml (mean±1 SD) in healthy subjects, 25.42±14.25 μg/ml in patients of periodontal disease and 9.47±5.48μg/ml in patients of edentulous jaw. The mean value in patients of periodontal disease was significantly (p<0.01) greater than that in healthy subjects.
The salivary lactoferrin level correlated positively with the transferrin level (r=0.318), the leukocyte count (r=0.483) and the probing depth (r=0.582).
The salivary protein level in patients of periodontal disease was 108.8±64.8 mg/dl which was higher than 63.1±24.4 mg/dl in healthy subjects, though the difference was not statistically significant.
When salivary protein bands were fractionated using cellulose acetate electrophoresis and silver staining, an Ig A band was darkly stained, an albumin band was faint and 2-3 bands were observed at the position of albumin in healthy subjects, whereas an albumin band was densely stained in addition to an Ig A band in patient of periodontal disease. In the electrophoretic pattern of proteins in gingival crevicular fluid, the same patients of periodontal disease showed densely stained albumin bands in a manner similar to salivary proteins. This was considered to result from leakage of a small volume of gingival crevicular fluid into saliva due to periodontal inflammation.
These results suggest that salivary lactoferrin and albumin can serve as useful markers of periodontal inflammation.

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Surgical orthodontic treatments are performed when restoration of a satisfactory occlusal relationship by conventional orthodontic treatments is considered to be difficult due to marked imbalance between the upper and lower jaws.
Since surgical orthodontic procedures, which involve separation of the mandibular, cause marked changes in the relative spatial relationship between the upper and lower dentitions in a short period, dynamic effects of traction by masticatory muscles may also change after the treatments. Moreover, as the stability of occlusion and adaptation of muscle function after treatments are closely related, functional assessments before and after the treatments are important when the treatments entail such drastic changes. In this paper, a clinical trial case is presented with the results of electromyographic analyses before and after surgery.
The patient was admitted for correction of reversed occlusion and received surgical orthodontic treatments after occlusal management until the end of the growth. The ANB value increased from -4.0° at the initial examination to -7.7° at the end of the growth (at the beginning of orthodontic treatments before surgery) but improved to -1.7°at the end of orthodontic treatments after surgery. Both the occlusal state and the esthetic results were satisfactory 1 year after the end of the dynamic treatments. Because of the asymmetric development of the lower jaw, the distance of surgical shift was 13 mm on the right side and 9 mm on the left side. The integral values of electromyograms of the bilateral anterior bellies of the temporal muscles, posterior bellies of the temporal muscles, and masseter muscles showed postoperative activity-related increases, but changes were observed also in the activity ratios among the dominant muscle and other muscles.

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The strength and persistence of antibacterial activity of a zinc phosphate cement containing silver inorganic antibacterial agent (BIKAHM-AK) to cariogenic bacteria were examined by in vitro growth inhibition assay. The disks made by mixing BIKAHM-AK and zinc phosphate cement showed sufficient antibacterial activity on cariogenic bacteria and the activity increased in a dose-dependent manner to BIKAHM-AK. The antibacterial activity was retained for at least 7 days without significant decrease even when the disks were immersed in saline. The persistence of the activity was observed in any disks containing 5-25 wt% BIKAHM-AK. These results suggest that the zinc phosphate cement containing BIKAHM-AK shows sufficient antibacterial activity to cariogenic bacteria and is useful for controlling formation of dental plaque in oral cavity.

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Gingival cysts in adults arise from odontogenic epithelial remnants and most commonly seen in the canine-premolar region of the mandible. This lesion is rare, in Japan, an extensive review of the literature revealed only one reported CARP arising from maxilla. We have encountered such a case, and report it here. A 28-year-old man was referred to our department on February 12, 2000, because of gingival swelling in the left first incisor region of the maxilla. He had previously consulted a dental clinic because of tenderness in the same region. It was hemispheric. the border was clear The patient had slight pain and tenderness. The surrounding teeth were all vital, and had no pain on percussion or mobility. A radiographic examination showed no abnormalities. We clinically suspected the swelling as an epulis. It was pathologically diagnosed as gingival cyst in an adult. The postoperative course has been good.

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The Tokyo City, Ohta ward health and welfare division conducted an evaluation of a model project to provide integrated in-home care of health and welfare services for the 1995 and 1996 fiscal years. Survey results of the model project are as follows : 1. There is a shortage of in-home care staff. 2. Food was not appropriate for the swallowing function of recipients. 3. More severe bedridden status corresponded to worse swallowing function. These problems translated to poor dietary habits among recipients. The integration of health and welfare services throughout the entire ward began in the 1997 fiscal year. Dental hygienists created a system of “care services for eating habits” based upon the results of the model project. These services are operated in cooperation with other occupations and organizations, including the district dental association. We are going to report on the system of dietary care services and the status as well as the results of the survey from the model project.

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