巻号一覧
19 巻 (1979)
- 3 号 p. 201-
- 2 号 p. 85-
- 1 号 p. 1-
19 巻, 2 号
選択された号の論文の5件中1～5を表示しています
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小椋 教順, 鈴木 陽典, 島野 達也1979 年 19 巻 2 号 p. 85-92
発行日: 1979年
公開日: 2010/10/21
ジャーナル フリーWe have often observed oblique incident X-rays' images in roentgenographs taken by the bisecting intra-oral technique because a dental X-ray film has a double emulsion and is about 200 pm in its thickness.
The double emulsion brings the double image. The thickness of the film and the oblique incidence of X-rays to the film make a difference in parallax between the image of the front and the back of the film which produce the double image. The parallax makes unsharpness image. We investigated the change in parallax unsharpness arising with incident angle of X-ray.
The results are summarized as follows:
1) The thickness of the dental film was 190.0±1.2 pm.
2) Geometric unsharpness of intra-oral roentgenography consists of a partial shadow of X-ray focus and additionally the parallax.
3) As increasing the incident angles of X-rays the unsharpness increases with an effect of partial shadow.
4) Unsharpness was the smallest at the geometric position in which partial shadow of X-ray focus was the smallest.
5) Parallax unsharpness have a small value in paralleing technique in which X-rays penetrate the film with small incident angles.
From these results, we could conclude that we could interpret without the parallax unsharpness by observing the film from the same direction as X-ray incident.
In order to reduce the X-ray oblique incident effect, radiograph must be taken with a small X-ray incident angle, not to bent the film, while taking, and we have to observe the film from the direction of incident X-rays.抄録全体を表示PDF形式でダウンロード (772K) -
岩崎 裕一, 上村 修三郎, 淵端 孟1979 年 19 巻 2 号 p. 93-101
発行日: 1979年
公開日: 2010/10/21
ジャーナル フリーMany lesions with cystic or cyst-like roentgenographic appearance are found in jaw bones. So-called simple bone cyst is one of the lesions occurring mainly in the young, and it usually shows no symptom.
Since panoramic roentgenography has become popular, such a latent lesion has been found more frequently. So-called simple bone cyst has to be differentiated from other cyst-ic or cyst-like lesions roentgenologically from a therapeutic point of view. Because in such cases adjacent teeth are mostly healthy, besides, spontaneous cure of the lesions could be expected.
Though there are many articles about these lesions, characteristics of the roentgenogra-phic findings of them have not been referred so far. The purpose of this study is to make clear the characteristic findings of this lesion roentgenographically, reviewing five cases of the lesions proved by operative and/or histological findings.
Consequently it was found that the roentgenographic findings of margin, form and nature of the radiolucency of the lesion are characteristic in many cases.
Especially in widely extended lesions two white lines showing the upper margin of the lesion could be detected. These white lines may be resulted from the extension of the lesion to both buccal and lingual sides of adjacent dental roots without total resorption of their lamina dura. In case of cortical bone expansion, only a mild expansion and a gradual transition from the normal to the expanded site could be recognized in spite of extensive enlargement of the lesion in the direction of long axis of the lower jaw.
For those detailed examination of the lesions the conventional periapical films and occlusal films are very useful.抄録全体を表示PDF形式でダウンロード (2746K) -
神田 重信, 中山 哲夫1979 年 19 巻 2 号 p. 102-104
発行日: 1979年
公開日: 2010/10/21
ジャーナル フリーPDF形式でダウンロード (1907K) -
1979 年 19 巻 2 号 p. 120-192
発行日: 1979年
公開日: 2011/06/03
ジャーナル フリーPDF形式でダウンロード (7319K) -
1979 年 19 巻 2 号 p. 193-196
発行日: 1979年
公開日: 2010/10/21
ジャーナル フリーPDF形式でダウンロード (481K)
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