In the present study, the distribution of fluoride (F) in the enamel carious lesions was investigated by means of the electron microprobe analysis. The ground sections of human permanent teeth (25), ranging from 11 years old to 60 years old, were first microradiographed and, then, were subjected to the elemental analysis. The line scan analysis performed along the line acrossing the lesions from the surface to the enamel-dentin junction and the point analysis performed at the outermost layer of enamel of the entire surface of crown indicate that the fluoride concentration increases prominently in the narrow surface layer of the lesions, whereas, in the remineralized subsurface layer, it does not change significantly. In the surface layer, the highest concentration of fluoride is usually observed at the outermost layer and decreases steeply towards the subsurface lesion, whereas Ca shows high and even concentration throughout this layer. The highly remineralized band observed often in the demineralized subsurface lesion also shows increase of fluoride concentration, although its degree is not so high as observed in the surface layer. The narrow hypermineralized layer appeared along the demineralization front does not show increase of fluoride. These findings are observed in both the smooth surface and fissure lesions. The fluoride concentration in the remineralized surface layer is not related to the mineralization degree, the depth of lesions, the demineralization degree in the subsurface lesion, the age of teeth, and the site of lesion in enamel.

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The course, origin and ramifications of the posterior deep temporal artery of sixty cats were investigated by utilizing the acryl plastic injection method. This artery arose from the maxillary artery distal to the origin of the inferior alveolar, or often in common with it, or rarely in only two cases from the rete mirabile of the maxillary artery distal to the origin of the middle meningeal artery. The posterior deep temporal artery gave rise to the temporomandibular joint, the lateral retial, the lateral pterygoid, the anterior branches and the masseteric artery, and it finally terminated into the superior, the superoposterior and the posterior branches within the insertion of the deep layer of the temporalis muscle. They supplied the muscles of mastication except for the pterygoideus medialis, which was supplied by the lingual branch arising from the lateral retial branch. This branch was similar to the maxillary artery in it's course, to the crab-eating monkey and man. The masseteric artery gave rise to the deep layer, the zygomaticomandibular and the maxillomandibular branches. The posterior deep temporal artery of the cat is similar to that of the dog in its ramifications, more than the crab-eating monkey, unless the lateral retial branch relating to the rete mirabile was not existent. The masseter muscle was mainly supplied by branches of the posterior deep temporal artery.

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After 30% HRP in saline was applied to mandibular canine tooth pulps in 6 adult cats, the openings of the pulp chambers were sealed with dental glass-ionomer cement. Prednisolone sodium succinate was administered intramuscularly every 12 h. to prevent an acute inflammation in the pulp tissues after surgery. Following survivals of 3 days, the trigeminal ganglia on both sides and the brain stem were removed and cut into frozen sections of 60 μm thick. All sections were treated according to the histochemical protocol of Mesulam (1978) and examined microscopically under brightfield illumination. Many HRP-labeled neurons were found in both the mesencephalic trigeminal nucleus (MTN) and trigeminal ganglion (TG) on the side ipsilateral to the HRP application, but none were found either in MTN or in TG on the contralateral side. In TG, labeled neurons were localized in its posterolateral region. All the labeled MTN neurons were pseudounipolar, and distributed rostrocaudally from A3.5-P3.5 within MTN; approximately 70% of them were located in MTN regions from P1.5-P3.0. Frequency distributions of soma diameters of labeled neurons were unimodal both in MTN and TG. The distribution of labeled MTN neurons ranged from 21-58 μm with a mode around 38 μm, while that of labeled TG neurons ranged from 18-59 μm with a mode around 33 μm; difference in the two distributions was significant (X² test, p<0.01). The present results indicate that the cell bodies of feline tooth pulp afferents reside not only in TG, but also in MTN.

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This study was performed to elucidate the effects of calcium hydroxide on the connective tissue and its initial calcification. The subcutaneous connective tissue of rats, injected with 1 mg of calcium hydroxide suspended in 0.2 ml of distilled water, was examined by electron microscopy at intervals of 5 minutes, 5 hours, 15 hours and 24 hours.
Five minutes after injection, most cells showed signs of degeneration and necrosis. Spherical bodies were observed in the extracellular matrix. They showed a tendency to increase in size and to fuse together with the passage of time. At 15 hours, fine needle-like structures were observed within degenereted cells and spherical bodies. At this time, calcification of collagen fibrils was seen at those sites which were in direct contact with the calcified spherical bodies. At 24 hours, calcification of collagen fibrils and necrotic cells was more advanced. Deformation or degeneration of collagen fibrils associated with calcification was observed.
These results suggest that cell degeneration and spherical body formation, caused by the subcu-taneous injection of calcium hydroxide, may initiate ectopic calcification.

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By using an ion analysis technique, it could be observed that all halides except fluoride were oxidized by the peroxidase systems at an acidic pH (3.75-5.0). In the reactions, the reactivity of chloride, bromide and iodide for the peroxidase-hydrogen peroxide systems increased in the order of the atomic number of halogen. That is, the oxidation of chloride was catalyzed only by myeloperoxidase, the oxidation of bromide by myeloperoxidase, lactoperoxidase and saliva peroxidase and the oxidation of iodide effectively by the all tested peroxidases, namely myeloperoxidase, lactoperoxidase, saliva peroxidase and horseradish peroxidase. Thiocyanate, a pseudohalide was also oxidized by the myeloperoxidase-, lactoperoxidase- and saliva peroxidase-hydrogen peroxide systems.

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As a chemically discriminating method of myeloperoxidase, lactoperoxidase, saliva peroxidase and horseradish peroxidase, the halide-required oxidation of fuchsin basic and acid red No. 106 mediated by the peroxidases in the presence of hydrogen peroxide were examined. Both fuchsin basic and acid red No. 106 were not directly oxidized by the peroxidase systems. Chloride and bromide ions mediated the reaction by the myeloperoxidase-hydrogen peroxide system, but fluoride ion did not. While bromide ion mediated the reactions by the lactoperoxidase and saliva peroxidase systems, fluoride and chloride ions did not and fluoride ion rather inhibited the bromide ion mediated oxidation. The horseradish peroxidase system had little effect on the dye oxidation even in the presence of fluoride, chloride or bromide ion.
These results show that myeloperoxidase, lactoperoxidase, saliva peroxidase and horseradish peroxidase could be classified on the basis of the halide dependent oxidation into three types of (i) myeloperoxidase, (ii) lactoperoxidase and saliva peroxidase and (iii) horseradish peroxidase.

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The purpose of this study was to understand the functional roles of macrophages in periodontal disease. In this study, we examined the effects of intraperitoneal injection of Bacteroides gingivalis, which is thought to be an etiological agent of adult periodontal disease, on production of interleukin-1 (IL-1) and various functions of mouse peritoneal macrophages, including Fc-receptor (FcR) mediated-phagocytosis, lysosomal enzyme activity, and cytostatic activity. Macrophages from B. gingivalis-injected mice (1 mg/mouse; dry weight) produced a significant amount of IL-1 as early as one day after injection, and peak production was observed on day 3 after the injection. However, the production declined by day 5. B. gingivalis also induced increases in FcR-mediated phagocytosis, acid phosphatase activity, and cytostatic activity as early as one day after injection with the peak being detected on day 3. IL-1 activity in the macrophage-conditioned medium (MCM) increased within the first 6 hr of the cultivation and then reached a plateau. The activity in the MCM was cell density- and concentration-dependent. The peak of IL-1 activity in the MCM was observed in the fractions having a molecular weight of 17, 000 as determined by Sephadex G-100 column chromatography. These results show that B. gingivalis has the ability to induce functional activation of mouse peritoneal macrophages, which suggests that similar activation of macrophages may occur in lesions of periodontal disease.

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The body weight and the activities of secretory enzymes in the salivary glands and in serum were examined in male Wistar rats following the induction of streptozotocin diabetes. Amylase activity in the salivary glands and serum of diabetic rats was reduced to about half compared with controls. Trypsin-like protease activity in diabetic rats slightly decreased in the submandibular gland. Insulin treatment of diabetic rats restored the activities of amylase and protease to their respective control levels in the salivary glands. These data show that the enzyme in acinar cells of the salivary glands is more affected than that in duct cells by streptozotocin-induced diabetic rats.

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Ultrastructure and distribution of Langerhans cells in the dorsal mucosa of mouse tongue were observed by light and electron microscopy and by ATPase histochemistry. The epithelium could be divided into papillary and interpapillary parts. Both papillae and interpapillae were orthokeratinized. The differences between the two parts were mainly due to the cellular characteristics of the prickle cell layer, granular layer and keratinized layer. In the interpapillae, tonofilaments in the cytoplasm of the prickle cells evenly dispersed without forming bundles, and the desmosomes were observed more clearly. The granular layer was less developed than that of the papillae. The cytoplasm of the keratinized layer stained with toluidine blue more lightly than that of papillae. By light microscopy, cells with clear cytoplasm occurred in the prickle cell layer just above the basal cell layer of interpapillae. They extended long cytoplasmic processes vertically, up to the granular layer and down to the basal layer. ATPase-positive dendritic cells were distributed in the interpapillae. By electron microscopy, Birbeck granule-containing Langerhans cells were observed in the interpapillae. The dendritic cells, which were observed as cells with clear cytoplasm by light microscopy or as ATPase-positive cells, agreed in morphology and distribution with the Langerhans cells which were observed by electron microscopy. In dd mice, ATPase-positive Langerhans cells were not observed at 2 weeks after birth, whereas they were observed at 3 and 4 weeks.

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