Shigaku = Odontology; journal of Nihon Dental College最新文献

The models of infection in the rabbits mandible using Streptococcus milleri and Bacteroides fragilis by the method of Satoh-Heimdahl were prepared. A penicillic peroral antimicrobial agent, lenamipicillin (LAPC), and pyridone carboxylic acid peroral antimicrobial agent, tosufloxacin tosilate (TFLX), were administered to infected and healthy groups. Drug concentrations in the serum, pus, mandible, maxilla, humerus, sternum, costa, ilium, femur, tibia, liver, and kidney were determined by a biological method. The data were submitted to pharmacodynamic analysis and compared. The following results were obtained. The concentration of LAPC in the serum and various bone tissues was 1.2-6.4 times higher in the infected group than in the healthy group. The concentration of TFLX in the serum and bone tissues was 1.1-3.7 times higher in the infected group than in the healthy group. Moreover, concentrations in the liver 1.1-fold and 2.1-fold higher in the infectious group than in the healthy group in the LAPC and TFLX administration groups, respectively, and 1.1-fold and 1.3-fold higher in the kidney in the LAPC and TFLX groups, respectively. Both LAPC and TFLX diffused to the pus more satisfactorily than to the serum. The Cmax ratios of pus to infected serum were 1.48 and 1.81 for LAPC and TFLX, respectively, and the AUC ratios of pus to infected serum were 1.31 and 1.62 in LAPC and TFLX, respectively. These results indicated that both LAPC and TFLX are distributed satisfactorily to the local foci in the mandible, and that their systemic diffusion exerted immediate clinical effects.

The three-dimensional structure of the connective tissue core (CTC) of each type of lingual papillae of Mogella wogura wogura was studied by scanning electron microscopy after removal of the epithelial cell layer and compared with the results obtained from light microscopy as well as transmission electron microscopy. Filiform papillae are densely distributed on the dorsal surface of the anterior part of the tongue. They were conical in shape and their connective tissue cores (CTCs) resembled wooden spoons at the tip of the tongue, while they were flower-shaped (Lysichiton camtschatense) at the middle part of the tongue. Fungiform papillae which had a round depression on the top were distributed sporadically among the filiform papillae, and contained columnar CTC with several plane striations running longitudinally along the lateral surface. A pair of vallate papillae was located at the boundary between the anterior and posterior tongue. Their CTC were flower shaped closely resembling a carnation. Giant conical papillae occupied the posterior marginal region of the tongue. These papillae contained much smaller conical CTC similar to the outer form. Light and transmission electron microscopic observations of the dorsal lingual epithelium revealed three different regions: anterior region to the filiform papillae, posterior to the papillae and interpapillary region. In the intermediate layers between the germinal layer and the surface layer of the anterior region to the filiform papillae, a large number of keratohyaline granules was observed, but the cornified layer was obscured. In the posterior region, keratohyaline granules were fewer in number and the cornified layer was clear and thick. In the interpapillary region, keratohyaline granules were few and a thin cornified layer was recognized. At higher magnification, small sized keratohyaline granules contained a large number of free ribosomes, suggesting a close relationship between the two. Odland bodies were found only on the interpapillary region.

The changes appeared in the developing dentin and enamel of rat upper incisor after single intraperiotoneal injection of cyclophosphamide (4-8mg/100g body weight) were investigated histologically and microradiographically. 1) Changes appeared immediately after the injection were karyolysis, necrosis and intercellular accumulation of tissue fluid in the preodontoblast layer at the cell proliferating stage and its neighboring pulp tissue, however, no particular change was observed in the adjacent inner enamel epithelium cells. Those changes were more prominent in the labial side than the lingual side and expanded their range with time after the injection and then were replaced gradually by the fibroblasts proliferated. 2) Changes appeared in the dentin secondarily were as follows: a. Hypoplasia of dentin made by the odontoblasts which were at the stage of cell differentiation at the time of the injection. This is probably due to early cessation of dentinoplastic activity. b. Hypoplasia of the dentin induced by the odontoblasts which were at the stage of cell proliferation at the time of the injection. This change was induced by odontoblasts recovered from the changes described in 1). c. Hypomineralization appeared in the dentin which places more incisally than the site of change a and have commenced its matrix formation after the injection. This change did not accompany hypoplasia. d. Slight hypoplasia appeared at the basal side of change b. This change was made by the odontoblasts proliferated after the injection. With time after the injection, "niche" formation became observable at the pulpal surface of dentin due to hypoplasias mentioned above. 3) Osteodentin formation became appear secondarily and expanded its range in the pulp adjacent to the portion of the changes described in 2). Early cessation of dentin described in b and c of 2) is due to cell dysfunction occurred by pressure induced by osteodentin formation. 4) At the developing enamel adjacent to the hypoplastic dentin, no particular change was observed in the progressive mineralization pattern, although distortion of contour of surface or slight hypoplasia were observed.

A clinical review was performed on patients who requested implantation and visited the Nippon Dental University Hospital during the five years from April 1985 to June 1990. This report describes patient characteristics and treatment results. 1. The total number of new patients was 127 (68 males and 59 females). Their ages ranged from 20 to 80 years. 2. The number of patients who were diagnosed with an indication for implantation and completed the 1st stage operation was 39 (30.7%). An additional 23 patients (18.1%) entered preoperative treatment and are waiting for their operation. Overall, implantation was indicated in 48.8% of all new patients. 3. The ages of patients at fixture installation ranged from 20 to 79 years (mean 60.54, S.D. 11.21) among the 39 patients (20 males and 19 females) who completed the 1st stage operation. As for the number of jaws, implantation was indicated in 40 jaws (21 in male patients and 19 in females). Maxillary implants were indicated in 8 jaws and mandibular implants were indicated in 32 jaws (1 male patient had indications in both jaws). 4. The total number of implanted fixtures was 198, of which 39 were installed in the maxilla, and 159 in the mandible (1 female patient was 5 mandibular fixtures installed at the University of British Columbia, Canada). 5. Of the fixtures implanted in 40 jaws, 94.9% of maxillary fixtures and 98.1% of mandibular fixtures remained stable after the 1st stage operation.(ABSTRACT TRUNCATED AT 250 WORDS)