Growth of the maxilla after early secondary bonegrafting to alveolar clefts

本論文の目的は, 顎裂を有する口唇裂口蓋裂患者に, 5歳ないし6歳という比較的早期に顎裂部への新鮮自家腸骨海綿骨細片移植(以下;骨移植)を行った場合の上顎骨の成長について調査し, 適切な骨移植時期を明らかにするものである。対象症例は, 東北大学歯学部附属病院顎口腔機能治療部で咬合管理を行っている口唇裂口蓋裂患者のうち, 1993年10月から1995年12月までの期間に, 同第二口腔外科で5歳ないし6歳時に顎裂部への骨移植を施行された20症例である。本研究の資料と方法は次の通りである。1.骨移植直後と3年以上経過後(平均;3.9年)に撮影したX線CTによる上顎骨成長の観察。2.5歳ないし6歳で骨移植された対象症例の9歳ないし10歳時と, 骨移植していない同年齢の症例のX線CTによる比較。3.対象症例と健常児の上顎骨成長の上顎石膏模型による比較。これらの研究の結果は, 1)X線CT分析では上顎犬歯部の幅径が, ほとんど成長せず, 骨移植していない場合に比較して有意に小さい傾向がみられた。2)上顎石膏模型分析では, 対象症例の上顎犬歯部幅径を健常児と比較したところ成長の抑制が認められた。以上より骨移植の手術時期は, 5歳ないし6歳の時期より, 永久前歯萌出後の8歳頃が適切な時期であることが示唆された。To define the optimal time for secondary bone grafting, we studied the growth of the maxilla after early secondary bone grafting in children with cleft lip and palate.Fresh autogenous cancellous bone and marrow harvested from iliac bone were grafted to the alveolar clefts.The study group comprised 20 children with alveolar clefts whose occlusion was being managed at Clinics for Maxillo-Oral Disorders, Tohoku University School of Dentistry.The subjects received bone grafts when they were 5 to 6 years old at the Department of Oral & Maxillofacial Surgery 11 between October 1993 and December 1995.The materials and methods of this study were as follows : 1.Maxillary growth was observed by means of X-ray computed tomographic(CT)scans obtained immediately after bone grafting and more than 3 years later(average, 3.9 years). 2.X-ray CT scans obtained at 9 or 10years of age were compared between patients who received bone grafts and those who did not receive bone grafts.3.Maxillary growth was compared between patients receiving bone grafts and those without clefts by means of maxillary plaster casts taken at selected intervals The following results were obtained : 1)Analysis of X-ray CT scans revealed that the width of the maxillary canine region did not increase, but decreased significantly as compared with patients who did not receive operation.2)Analysis of the alveolar arch by means of maxillary plaster casts, showed that the width of the maxillary canine region in patients with clefts was smaller than that in children without clefts, indicating delayed maxilllary growth in the former These results suggest that the optimal time for bone grafting is when patients are about 8 years old, after the maxillary permanent incisors have erupted, rather than 5 to 6 years of age