Influence of Scar Tissue Formation on Ultrastructure of the Palatal Bone Surface in Rats

Abstract

This study examined the ultrastructural changes in the palatal bone surface induced by scar tissue formation on the palate. Male 20-day-old Wistar rats were divided into experimental and control groups. In the experimental group the bilateral mucoperiosteum was excised in the lateral one third of the palate. At the 6th week following the surgical procedure, changes in the lamina propria and bone surface of the denuded bone area were investigated by light and scanning electron microscopy . In the control group, fibrous connective tissue with horizontally oriented collagen fibers were found beneath the epithelium , and there was periosteum along the bony surface. Scanning electron microscopy of the control group showed regularly arranged blood vessel holes on the bone surface. The experimental group showed dense fibrous connective tissue with matted collagen fibers were present in the lateral operated area without periosteum . Scanning electron microscopy showed rough bone surface with vague appearance of collagen bundle structures. Fewer blood vessel holes were seen on the bone surface than in the control group . The results suggested that scar tissue formation by mucoperiosteal denudation of the palate deteriorates vascular supply to the bone, which results in the palatal bone growth inhibition. 抄録:口 蓋裂患者では,幼 少期にpush back法 による口蓋形成手術が広く行われているが,術 後の瘢痕組織が 上顎骨の成長を抑制すると報告されている。本研究では,実 験的に生後20日 齢ラットの口蓋粘膜を一部除去して 瘢痕形成を行い,術 後6週 。 対照群の口蓋粘膜は,角 化重層扁平上皮,上 皮下の線維性結合組織よりなり,口 。実 験群では,不 規則な角化重層扁平上皮とその直下に瘢痕性結合組織がみられ,骨 。走査電顕 〒814-0193 福 岡 県福 岡 市早 良区 田村2-15-1 川鍋 仁ほか:ラ ツト口蓋部瘢痕形成が骨表面の微細構造に与える影響 181 像では,対 ,ま た骨表面の粗〓化と骨基質の膠原線維束の不明瞭化が認 められた。以上より,術 後の瘢痕形成は骨への栄養供給の低下とともに ,口 蓋骨の成長に影響を与えることが示 唆された。