The interspecific relationships of the dental arch shapes and dentitions were investigated in colobus monkeys in order to provide the basic data for the study of the tooth to denture base discrepancy. The materials for the present study were 75 female dry skulls of 3 species of colobus monkeys (Colobus badius, Colobus verus, Colobus polykomos).
Most of colobus monkeys have mandibular protrusion or edge-to-edge bite. The constricted dental arch of the maxillary premolars was often observed, and rotated teeth were observed on the maxillary and mandibulary premolars. In the maxilla, the primate space was clearly noticeable, but in the mandible the C-P₃ space that was considered as the mandibulary interdental space of the primate type was not always to be seen.
In the case of Colobus badius, the arch shapes were long and narrow, especially in the maxillary premolars the arch width was remarkably narrow. But mandibular premolars protruded from the arch to the buccal side. In Colobus verus, the arch widths of molars were wide, but that of premolars were narrow, so the outlines of the arches were uneven. In Colobus polykomos, the arches were relatively wide, outlines of arches were smooth.
The results of the principal component analysis showed the interspecific dental arch size relation was not in agreement with that of the shape relation. From these facts the interspecific relationships of the dental arch shapes in the colobus monkeys could not be explained from an allomorphosis viewpoint.

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Fluorapatite was formed on the enamel surface of extracted teeth by the gelatin gel method, and a study was made on the influence of salivary constituents and protein membrane on the solubility of the produced fluorapatite by determining the rate of elution of Ca and P. As regards the types of salivary constituents, the rate of elution of Ca and P decreased in the order of albumin solution>lysozyme solution>polyvinyl pyrrolidone solution>mucin solution. As to kinds of protein membrane, the rate of elution of Ca and P increased in the order of mucin aqueous solution<mucin-extracted saliva solution<whole saliva<parotid saliva<extraparotid saliva<albumin aqueous solution, therefore, it is suggested that an interaction of the protein of parotid saliva and mucin being contained in the extraparotid saliva would control the solubility of the produced fluorapatite. Furthermore, it is also implied that whole saliva, compared with parotid saliva and extraparotid saliva, would not act briskly on the solubility of the fluorapatite produced on the tooth surfaces by the gelatin gel method.

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Morphological changes of aging on the salivary glands of Mongolian gerbil (from 4-month-old to 48-month-old) were investigated by means of light microscopic, electron microscopic and cytochemical methods. This study especially focused on the effect of aging on the acinar cells of parotid and submandibular glands. The most prominent changes noted in both the acinar cells of parotid and submandibular glands were ultrastructual varieties of the Golgi-complex components. In the acinar cells at 4 months after birth, a large numbers of transport vesicles were found between the rough endoplasmic reticulum and the cis side Golgi complex. However, few transport vesicles were seen in this area in the cases of aged animals. Some acinar cells of animals more than 36 months of age had distended rough endoplasmic reticulum. In these animals, some secretory granules might be fused to each other forming a large vacuole like structure occupying the whole cytoplasm of the acinar cells. In some acini of 48-month-old animals, the acinar cells contained irregular shaped secretory granules in their cytoplasm. There was an age-related increase in the number of cells characterized by dense bodies. indicating positive activity of acid phosphatase.

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In the mature mouse (C57BL/6SrSlc) two-month postnatal morphological changes in the incisive suture (InS) following the excision of the incisors in the upper and lower jaws at the level of their gingival margins were observed histologically. The incisors were excised repeatedly every three or four days because these teeth erupted continuously.
The InS of the mature mouse exhibited the complicated interdigitation of the well-developed bone trabeculae at the sutural surfaces of the premaxilla and the maxilla. The bone trabeculae of each bone were firmly connected to each other with collagen fibre bundles of regular orientation.
Seven days after excision, the collagen fibre bundles became thinner and their number decreased. Fourteen and twenty-one days after excision, osteoclasts appeared and the blood vessels proliferated and dilated in the suture. At this stage, the sutural surfaces altered and the unused collagen fibre bundles disappeared. Twenty-eight days after excision, the InS reformed. The collagen fibre bundles were thin in thickness and few in number compared with those in the InS of the mouse at sixty days postpartum.
The incisors regenerated and regained their masticatory function after we discontinued the excision experiments. The InS of these mice showed morphologically a recovery of it's connecting function with a remarkable formation of collagen fibre bundles.
The thickness and number of the collagen fibre bundles in the sutures of the mice which were fed a powder diet indicated an intermediate state between those of the InS of the mouse at sixty days postpartum and at twenty-eight days after the excision of the incisors.
These results indicate that the morphology of the InS is closely related to the intensity of the masticatory function of the incisors.

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The effects of testosterone propionate (TP) on wound healing of rat calvariae and the growth of the femur and the possible antagonism of such effects by cyproterone acetate (CPA) were studied. Three-week-old male rats were castrated, and one week later two holes were drilled into their calvariae and TP and/or CPA were administered s. c. for 2 weeks (T: 1, 2 and 5 mg/kg; CPA: 5, 10, 20 and 40 mg/kg; TP 1 mg/kg+CPA 10 mg/kg; TP 2mg/kg+ CPA 20 mg/kg). After daily administration of the drugs, the rat body weight was measued and the calvariae containing the wound holes were isolated and soft x-ray photographs were taken. The area of each hole was then measured on the x-ray film. In the case of the groups administration for TP 2 mg/kg and/or CPA 20 mg/kg, the calcium (Ca) and hydroxyproline (HP) contents in the wounded and non-wounded portions of the calvariae were also determined. The results obtained were as follows: 1) The decrease in the body weights of the rats due to the castration was significantly inhibited by TP, and this effect of TP was clearly antagonized by CPA. But the body weights were decreased by CPA. 2) The reduction in the wound hole area was significantly delayed after the castration. TP administration accelerated the reduction of the area dose dependently. 3) CPA showed similar dose dependent effect to TP in higher dosage than TP but this effect was weaker than TP. The effect of TP showed a tendency to be antagonized by the simultaneous administration of CPA, and the value of the area showed about the same as the castrated value or approached that of the castrated value. 4) The growth in the femur was significantly inhibited by castration and TP administration improved that, espcially 2 and 5 mg/kg of TP was remarkable. CPA significantly antagonized the TP effect. 5) The castration-induced reduction in HP content of the wounded portion was inhibited by TP, and this effect was antagonized by CPA. A similar tendency was observed for the Ca content of the wounded portion and for both HP and Ca contents of the non-wounded portion of the calvariae; however, the effects were not so clear as in the case of the HP content of the wounded portion. 6) The decrease in relative weights of prostate, seminal vesicle, and levator ani muscle due to the castration was cleary inhibited by TP, and the TP effects were antagonized by CPA. These results suggest that TP accelerated the regeneration of bone in wounded calvariae and bone growth of castrated rats, and CPA maybe act as an agonist-antagonist of androgen on wound healing and growth of bone.

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To clarify the localization of alkaline phosphatase (Al-Pase) during the development of the mouse submandibular and sublingual glands, histological and histochemical time course observations were made from the 16 th day of fetal life to the 12 th postnatal week. On the 16 th day of fetal life when the epithelial terminal cells still showed the end buds, Al-Pase activity was detected on every cytoplasmic membrane except the basal membrane side of the end buds. On the 18 th day of fetal life when the terminal tubule began to appear, Al-Pase activity was limited only to the luminal surface membrane of the terminal tubule cells and the activity was negative in the myoepithelial cell precursors. After the 2 nd postnatal week, Al-Pase activity was also observed on the cytoplasmic membrane of the myoepithelial cells around the duct system and the acini, whereas the activity in the luminal surface membrane of the terminal tubule cells declined later on. On the 4 th postnatal week Al-Pase activity was seen only on the cytoplasmic membrane of the myoepithelial cells, but the activity in the luminal surface membrane of the terminal tubule cells had disappeared. These results indicate that two types of Al-Pase, which are comparable to those of the fetal and adult types in rats as pointed out by Fukushima[Tr. Soc. Pathol. Vol. 70 (Supple.), pp.45-64 1981], are also expressed in a successive manner in the mouse salivary gland ontogenesis, as in rats, although there are some differences between mice and rats. During the histochemical study, the author developed a modified fixation-embedding technique to preserve Al-Pase activity as well as fine detail of the histological structure.

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The purpose of this study was to investigate the inhibitory mechanism of colchicine on the osteoclastic bone resorption. Male Wistar rats, weighting 120g on average, were injected intravenously with colchicine at the dose of 1.0 mg/kg. The control rats were injected with physiological saline. They were sacrificed at 1, 2, 4 and 8 hours after the injection. Osteoclasts located in the proximal metaphysis of tibia were examined with an electron microscope. Some specimens were stained for acid phosphatase. After the colchicine injection, the number of microtubules in the cytoplasm decreased and the Golgi apparatus moved from the circumunclear area and spread throughout the cytoplasm. Acid phosphatase-positive trans Golgi network became difficult to detect in the dislocated Golgi apparatus. In the central area of the cell, clusters of small vacuoles and vesicles which contained various quantities of amorphous material appeared. Acid phosphatase activity was detected in these vacuoles and vesicles. The structure of the ruffled border was disturbed. In the organ culture of mouse calvaria, colchicine inhibited PTH-enhanced bone resorption and the release of β-glucuronidase and acid phosphatase dose dependently. The results obtained in this study suggested that the disturbance of microtubules by colchicine causes a functional inhibition of both the Golgi-lysosomal system and the ruffled border and subsequently reduces the bone resorbing activity of osteoclasts.

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The present study was pursued to investigate the effects of colchicine on the iron transport and the release process in ameloblasts of the rat incisor by electron microscopy. Male Wistar rats, 120 g body weighing on average, were injected intravenously with colchicine at a dose of 1.0 mg/kg and sacrificed at intervals of 8, 16, and 24 hours. The control rats received physiological saline of the same injected volume as colchicine. Ultrastructural observations of the ameloblasts were performed from the pigment release stage to the regression stage. In the controls, the iron-containing pigment granules were found to be distributed mainly in the middle part of the ameloblasts and their number gradually decreased from the pigment release stage to the incisal end. Within 8 hours after the colchicine injection, the number of pigment granules increased and they accumulated in the middle and distal part of the cell. The nucleus moved toward the distal direction. These findings were more remarkable at 16 and 24 hours. The shape of the ameloblasts were transformed to a rounded profile and many vacuoles appeared in the proximal portion of the cytoplasm. Further, the cytoplasmic microtubules decreased in number. Colchicine seemed to inhibit the iron transport and the release process in the ameloblasts by interrupting the digestion system of the pigment granules and/or the release process of iron from pigment granules. These observations suggest that the cytoplasmic microtubules are important for the regulation of the transport and the release of iron in the rat incisor ameloblast.

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Morphologic effects of maternal alcohol intake on skull, mandible and tooth of the offspring in BALB/cJ mice were studied. Adult female mice were given orally 20% alcohol in drinking water and a diet before and during pregnancy. Maternal blood alcohol levels showed 284.0±1.4 mg/100 ml on gestation day 12.5. Skull and mandible were dissected, weighed and processed for statistical analysis and light microscopic examinations. The results were as follows: 1) The total maternal body weights showed no significant difference during pregnancy between the control and alcohol-treated groups, but the offspring of alcohol-treated females showed weight deficit through the period of gestation and postnatal 28.5 days. 2) The mandible weight of the offspring was less in the alcohol-treated group than the control group through a postnatal period of 28.5 days. 3) The growth of the skull and mandible in the offspring was retarded in the alcohol-treated group through a postnatal period of 28.5 days. Significant statistical differences of the growth were seen in the posterior region of the mandible. 4) Appearance of the tooth germ was delayed on gestation day 14.5. 5) Calcification of the tooth was delayed on postnatal day 1.5. 6) Retardation of the tooth eruption was seen on postnatal day 14.5. It is indicated that the offspring associated with maternal chronic alcoholism showed retardations in their skeletal and dental development, and failed to catch up to the growth of the control animals during a postnatal period of four weeks.

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