- 著者
- 宮本 謙治 下田 妙子 伊藤 明彦 嶋村 昭辰
- 出版者
- 九州歯科学会
- 雑誌
- 九州齒科學會雜誌 : Kyushu-Shika-Gakkai-zasshi (ISSN:03686833)
- 巻号頁・発行日
- vol.40, no.5, pp.1124-1136, 1986-10-25
- 被引用文献数
- 2
The morphological and histological characteristic of the teeth of the Afghan pika, Ochotona rufescens rufescence were studied in 12 animals, weighing about 200-300 grams. After the skulls were soft X-rayed, some were prepared for examination on a dissecting microscope and the others for non-decalcified or calcified sections. The main results obtained were summarized as follows. 1. All of the incisors and molars were rootless. 2. The labial and distal surface of the outer incisors were covered with enamel. On the other hand, it was absent on the palatal and mesial surface. For the inner incisors, the four surfaces were covered perfectly with enamel. 3. Enamel was absent on the buccal surface of the upper molars and on the lingal surface of the lower molars. 4. The longitudinal groove found in the labial surface of the outer incisors was filled comparatively thickly with cellular cementum. In the molars, except the lower M_3, bonelike cementum was supplemented along the longitudinal grooves of each lobule (the isthmus) and reinforced the connection between the two. 5. In both the incisors and molars, all of their surfaces including the filling cementum were covered with remarkably thin acellular cementum. 6. The ameloblast being in the process of forming young enamel derived from the enamel organ in the basal end were degenerated gradually toward the occlusal side and were replaced suddenly with the cementoblasts derived from the dental sac. Consequently, on the region cementum covered over enamel (on the occlusal side). Where enamel was absent, neither ameloblast nor inner enamel epithelium was observed. Instead, only short cementoblasts were seen. 7. As compared with the domestic rabbit, the following differences were pointed out. a. The upper M_3 was absent in this animal. b. The lower M_3 of the animal were of single lobule, while those of the rabbit were of double lobi. c. Distribution of enamel in the mesial and distal surfaces of the outer incisors differed slightly between the two animals. d. The region lacking the molar's enamel in the pika tended to be a very little wider than that of the rabbit.
1 0 0 0 OA アンケート結果からみた第104回日本消化器内視鏡学会近畿支部例会Web開催の功罪
- 著者
- 神田 暁博 脇坂 恭加 大槻 晋士 水田 寛郎 伊藤 明彦 辻川 知之
- 出版者
- 一般社団法人 日本消化器内視鏡学会
- 雑誌
- 日本消化器内視鏡学会雑誌 (ISSN:03871207)
- 巻号頁・発行日
- vol.63, no.7, pp.1397-1401, 2021 (Released:2021-07-20)
COVID-19感染の流行により,数々の学会が中止や延期,開催方法の変更を余儀なくされている.第104回日本消化器内視鏡学会近畿支部例会は,急遽Web閲覧方式に変更して開催した.発表演題は音声付きのパワーポイントスライドで2020年6月27日から2週間閲覧可能とした.参加は1,000人と過去の通常開催を上回る登録が得られた.アンケートからは自由な時間に閲覧できることや遠方でも参加しやすいなど肯定的な意見が多かった.一方,双方向での質疑応答ができなかったなどの問題も指摘された.今後の日本消化器内視鏡学会支部例会は,Web開催でも参加者が十分に議論に参加できるよう技術的な克服が課題である.
1 0 0 0 創造的自己表現のための情報教育
1 0 0 0 OA 歯冠修復物のマージン形態ならびにその組織親和性について
- 著者
- 伊藤 明彦 郭 明毅 劉 嘉東 細川 隆司 永富 勝広 村上 繁樹 内田 康也 帆鷲 郷一 内山 長司
- 出版者
- 九州歯科学会
- 雑誌
- 九州歯科学会雑誌 (ISSN:03686833)
- 巻号頁・発行日
- vol.43, no.2, pp.351-359, 1989-04-25 (Released:2017-12-21)
In this study, we investigated the effects of the marginal surface configurations of different crown systems on the periodontal tissues. The morphology of the marginal surface of the crowns was examined by using a light- and a scanning electron microscope. In addition, biocompatibility of the materials used for crown margins was also examined by a subcutaneous implantation. The results were as follows : 1. The margins of the Ag-Pd-Au alloy full cast crowns fabricated by a conventional method were sharp and wavy with irregularities. 2. The modified method in which the margins of the Ag-Pd-Au alloy full cast crowns were rounded slightly with silicone rubber wheels was effective to make the margins smooth and round. 3. The glazed porcelain jacket crowns with metal foil copings produced sharp marginal openings because of the occurrence of a microfracture in a glass state of the ceramics. 4. The conventional ceramo-metal crowns displayed the irregularities of the surface adjacent to the boundary between metal collar and porcelain. One of the reason of this observation might be the exposure of a opaque porcelain of the crowns. 5. In the collarless ceramo-metal crowns, the marginal line configulations were totally rounded. 6. The DICOR crowns exhibited the smoothest marginal surfaces and the slightly rounded margins. 7. In the study of subcutaneous implantation, the porcelain (VMK 68) and the castable ceramic (DICOR) showed better histopathological findings than the gold alloy metal.