永久歯の萌出遅延を契機に鎖骨頭蓋異骨症と診断された二卵性双生児の姉妹例

A Case Report of Fraternal Twin Sisters who were Diagnosed with Cleidocranial Dysostosis with Delayed Eruption of the Permanent Teeth

番匠谷 綾子

海原 康孝

中江 寿美

鈴木 淳司

香西 克之

小児歯科学雑誌

鎖骨頭蓋異骨症は, 鎖骨の低形成もしくは欠損, 頭蓋骨骨化生涯, 歯の形成以上, 低身長などを特徴とする常染色体優性遺伝の骨系統疾患である。

今回著者らは, 永久歯の萌出長延を主訴に当科を受診し, それが契機となって鎖骨頭蓋異骨症と診断された10歳10か月の二卵性双生児姉妹を経験した。

諸検査により次のような姉妹に相似した所見を得た。

1. 鎖骨に両側性の部分欠損を認めた。

2. GH補充療法を行っているにも関わらず低身長を認めた。

3. 頭蓋骨に大泉門の閉鎖不全, wormian boneが存在した。

4. 多数の乳歯が存在し, 残存乳歯の歯根吸収もほとんど認められなかった。

5. 永久歯は姉に6歯, 妹に7歯のみの萌出を認め, その他の埋伏永久歯の萌出もかなり遅れていた。

6. 埋伏過剰歯は, 姉には上顎3歯, 下顎6歯の計9歯, 妹には上顎3歯, 下顎5歯の計8歯を認めた。

7. 下顎の過成長と下顎骨の前方位による著しい反対咬合を呈していた。

8. 歯列弓は上下顎ともに著しく狭窄していた。

9. 高口蓋で正中口蓋縫合に沿う裂溝を認めた。

Cleidocranial dysostosis(CCD) is a genetic bone development disorder which is characterized by incomplelely formed collar bones, late closure of the sutures and the fontanels of the skull, delayed eruplion of the permanent teeth, and so on. We describe 10 years old fralternal twin sisters suffering from cleidocranial dysplasia. They were referred to our hospital by their family dentist because of they had numerous impacted permanem teeth. Both of them presented typical characlerislics of this disease in the skllll, the clavicles, and the maxillofacial area.

They had slopping shoulders, although they were not able to bring their shoulders together in front. They were in short posture and had an inverted pear-shaped skull and a saddle nose. Radiographs revealed the partial absence of their clavicles, typical cranial abnonnalities which were incompletely closure of lhe sutures and fontanels of the skull, and wormian bones. ln both cases. mandibular prognathism was characteristic. According to cephalometric x-ray analysis, hypergrowth of the mandibular bone was obvious, but undergroeth of the maxilla was not noticeable.

Both of them had prolonged retention of the primary teeth and delayed eruption of the permanent teeth. The first sister had 35 impacted teeth including 9 supernumerary teeth in her jaws. The second sister also had 34 impacted teeth including 8 supernumerary teeth. Their hard palates were high and narrow with a groove running down the center.

鎖骨頭蓋異骨症

双生児

萌出遅延

埋伏歯

Runx 2

Cleidocranial dysostosis

Twin

Impacted tooth

lmpacled tooth

医学 [ 490 ]

日本語

日本小児歯科学会

Copyright (c) 2007 Authors, 日本小児歯科学会

[ISSN] 0583-1199

[NCID] AN00116228