Nine-week-old male Wistar-strain rats were used, corresponding to adulthood in human beings. Calcium deficiency and low calcium diet were fed for 3 weeks, followed by activated Vitamin D_3 for 1 week, and standard diet for another 3 weeks. The effect on formation of bone matrix was investigated, and results were as follows. 1. Body weight No significant differences were revealed among the three groups after 7 weeks of study. 2. Radiographic findings and bone density Calcium deficiency group showed thinner width of interosseous and medial cortice than control group. Bone density showed no significant differences among the three groups. 3. Histopathological findings Bone matrix of diaphyseal cortex was shown densely distributed in control group, inner and outer circumferential lamellae thick, and Haversian system well-formed. Calcium deficiency group showed such findings of bone loss as decreased width of outer circumferential lamellae, decreased Haversian system number, and cavitated osteocytic lacunea. Formation of bone matrix in low calcium group was shown almost the same as in control group. 4. SEM findings Many osteocytic lacunae were seen on superficial layer of interosseous and medial cortice in control group, collagen fibers and deposition of calcifying vesicles were present. Calcium deficiency group showed no significant differences morphologically compared with control group, but the bone contour showed small. Osteocytic lacunae showed indistinct borders with the from surrounding matrix, and irregular-shaped resorptive lacunae were seen. In low calcium group, no changes were found in interosseous and medial cortice compared with control group. The regular-arranged collagen fibers were seen in bone formative layer, the collagen fibric network got dense in superficial area. 5. Hematologic findings Electrolytic, biochemical, and endocrinological examinations showed no significant differences among the three groups. From the aforementioned results, combined treatment with calcium-containing dietary and activated Vitamin D_3 helps with the improvement of bone structure in bone loss resulting from calcium deficiency, as long as bone formation is normal until the adulthood with standard diet feeding. With low calcium diet, bone metabolism was shown to function well, and resulting bone matrix formation almost the same as control group.

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We evaluated the usefulness of the serum TNF-α levels of 38 patients with oral squamous cell carcinoma and the relationships among the serum TNF-α levels and these tumor markers. The mean serum concentration of TNF-α for the patients with O-SCC was significantly higher than that in the healthy controls. The mean serum concentrations of TNF-α were also significantly higher in the good-prognosis group than in the poor-prognosis group. The survival curve revealed a better prognosis for the serum TNF-α-positive patients than for the serum TNF-α-negative patients. A significant correlation was thus observed in the serum TNF-α levels and two tumor markers (SCCA, IAP). An evaluation of the serum TNF-α levels in O-SCC patients is thus considered to be a valuable tumor marker for the diagnosis and prognosis of O-SCC patients.

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[in Japanese]

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The purpose of the present study was to investigate the relationship between the presence of the tension ridge and the severity of periodontal disease and the morphological characteristics of the dentition. Thirty seven patients with and without periodontal disease were recruited from the pool of the patients. The following clinical parameters were recorded by a single dentist ; probing pocket depth (PPD), probing attachment level (PAL), bleeding on probing (BOP). In addition, 14 series of dental radiographs, oral photographs, and the study cast impression were taken at the initial examination. The patients were classified into four groups in accordance with the presence of the tension ridge and the severity of the periodontal disease. Four groups constituted T(+) I ; patients who had the tension ridge in conjunction with moderate to severe periodontitis, T(-) I ; patients who did not have the tension ridge in conjunction with moderate to severe periodontitis, T(+) II ; patients who had the tension ridge in conjunction with healthy to slight periodontitis, and T(-) II ; patients who did not have the tension ridge in conjunction with healthy to slight periodontitis. Comparison was made among the groups as to PPD, PAL and BOP. PPD and PAL in palatal site of maxillary premolar, canine and incisor, and those in buccal site of maxillary incisor showed greater values in T(+) I as compared with T(-) I. BOP in palatal site of maxillary premolar, canine and incisors, and those in buccal site of maxillary premolar showed greater values in T(+) I as compared with T(-) I. There was no statistically significant difference between T(+) II and T(-) II in the PPD and BOP. Furthermore, the measurments of the study casts were compared among the groups. The width of the dentition showed no statistical difference between any two groups. The vertical length between central incisors and first molars in T(+) I was longer than that in T(-) I. These results indicated that the patients who had tension ridge in conjunction with periodontitis showed local progression of the periodontitis and the typical morphological characteristics of the dentition. For the diagnosis and the treatment planning of the periodontitis for the mouth breathers, these findings may provide useful information.

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The general expectation of patients who come in for orthodontic treatment is not only to obtain a good occlusal relationship but also to achieve a certain level of esthetic improvement. Therefore, contemporary orthodontic treatment has to take facial structures and varieties into consideration. Consequently this experiment was based on previous research on most preferable profiles, and we once again, conducted survey the preference of people concerning the non-preferable profiles. The followings are the results of this survey. 1. The least preferable profiles are the ones with lips deficiencies (lip retraction and protrusion). 2. Among assorted types of lip deficiency, protruding lips are the least favored. 3. This was the choice of all those tested among all groups of profiles. The results of survey are in accordance with those of previous survey on ideal profiles.

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Tooth preparation of veneer crown is a very important step in prosthodontic treatment. The following basic principles are necessary to fabricate the esthetic form and good fit of veneer crown. 1. Have a good grasp of the restorative from before tooth preparation. 2. Prepare in your mind for the ideal form preparation. 3. Use the air turbin exactly. 4. Use magnifier to prepare. 5. Select the instrument that is suitable for the form preparation. 6. Prepare fully on labial tip part of abutment tooth. 7. The end of shoulder type is more lingual than conntact point. 8. Don't undercut when shoulder type is prepared. 9. Prepare smooth finishing line and clear margin cervical part. 10. Don't make outline of abutment tooth too sharp.

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