アブストラクト(26巻1号:神奈川歯学)

神奈川歯学

Japanese

Title : 骨格性下顎近心咬合の顎顔面骨格形態の年齢的変化 - 横断的頭部X線規格写真資料による研究 -
Subtitle : 原著
Authors : 鴨井節子, 鈴木祥井
Authors(kana) :
Organization : 神奈川歯科大学矯正学教室
Journal : 神奈川歯学
Volume : 26
Number : 1
Page : 25-33
Year/Month : 1991 / 6
Article : 原著
Publisher : 神奈川歯科大学学会
Abstract : 「緒言」 下顎近心咬合は本邦における矯正患者の15~35%を占め, 欧米の2~3%に比べ, 明らかに高率を示し, 日本人を対象とする矯正治療の中では本症例の治療が重大な位置を占めている. 下顎近心咬合, とくに顎顔面の骨格の発育異常を伴った骨格性下顎近心咬合は, その骨格の偏位によって矯正学的咬合再構成を困難にしていることが多い. このような不正咬合の発現を予防し, あるいは咬合を再構成することによって骨格に調和した安定な咬合を得るには, 下顎が上顎に対して正常な位置よりも近心位で咬合するという現象がどのように発現してくるのかということを知る必要がある. 下顎近心咬合の成立を説明するもののひとつに, 下顎骨そのものの遺伝的な過剰発育がある. 下顎骨の成長の大部分は, 下顎頭軟骨の成長に依存している. したがって, 遺伝的な下顎の成長異常は, 根本的には, 下顎頭軟骨細胞の遺伝子レベルでの疾患ということになろうが, これを示唆するような報告はいまのところみあたらない.
Practice : 歯科学
Keywords : 下顎近心咬合, 咬合平面, 経年的推移, 機能的適応

English

Title : Morphological and Developmental Characterizations of Skeletal Mesio-Occlusion Using Transversal Specimens of Roentogenocephalogram
Subtitle :
Authors : Setsuko KAMOI, Yoshii Suzuki
Authors(kana) :
Organization : Department of Orthodontics, Kanagawa Dental College
Journal : Kanagawa Shigaku
Volume : 26
Number : 1
Page : 25-33
Year/Month : 1991 / 6
Article : Original article
Publisher : Kanagawa Odontological Society
Abstract : [Abstract] A radiographic cephalometric study was done to evaluate the growth of the dento-facial complex in developing mandibular mesio-occlusion using 340 Japanese subjects from ages 3 to 16. Samples were divided into two groups, namely high angle and low angle groups, based on the angulation of the mandibular plane angle (FH-MP), that is 29 degrees. Results revealed that the most important morphological feature of skeletal mesio-occlusion was the alteration in the occlusal plane (OP-MP) with a relatively stable FH-MP angle, indicating a continuous vertical elongation of molars. It was suggested that in response to this, the mandible rotated forward with anterior displacement, thus AB-MP angle decreased with age. Futhermore, APDI anp ODI values indicated that in developing mandibular mesio-occlusion, alteration of vertical dimension is a more important factor than antero-posterior relation of the jaws especially in the high angle group, suggesting that there were developmental differences between high angle and low angle groups of mesio-occlusion. It was also suggested that the decreasing posterior cranial angle (P-S-Ba) which was induced by the descending movement of maxillary complex played a role in the increment of posterior vertical height. Based on these findings, it was concluded that the development of skeletal mandibular mesio-occlusion is attributed to the increasing vertical dimension particulaly on the posterior part of dentition and consequently in response to this, the functional forward rotation and forward displacement of the mandible.
Practice : Dentistry
Keywords :