Allogeneic bone grafts into maxillary alveolar cleft in rats -Bone inductive activity of demineralized bone matrices stimulated by electromagnetic fields-

本研究的目的是探讨同种异体骨移植是否可以代替自体骨移植修复牙槽骨裂。下面是实验的步骤。上颌牙槽裂隙动物模型的建立。在手术过程中，在上颚组织中切开一个切口，将口腔黏膜抬起，露出前颌。在牙科耳机上用套管钻出一个圆孔。在上切牙后的前颌中线处预备1个直径2mm的孔。让缺损充满血凝块，修复其上的软组织。术后，动物继续满意地进食。术后35 d影像学及组织学检查均未见骨愈合。脱矿骨基质在上颌牙槽裂隙动物模型中的骨诱导作用。根据Reddi等人的研究，同种异体骨移植物在上颌牙槽沟内的移植使用的是由大鼠长骨制备的脱矿骨粉。术后第21天和第35天，影像学和组织学均见腔内新骨形成。电磁场刺激脱矿骨基质诱导大鼠上颌牙槽裂隙成骨的实验研究。将同种异体骨移植到上颌牙槽裂的大鼠暴露于脉冲电磁场（pemf）中，脉冲电磁场是由脉冲电流在线圈中产生的1毫秒的反极性脉冲，重复频率为15 Hz。暴露于pemf的大鼠骨移植托盘受到碱性磷酸酶活性的刺激，<^(45)Ca>掺入。结果表明，电磁场可刺激脱矿骨基质的骨感应活性。因此，我们认为在临床上我们可以用电磁场刺激的同种异体骨移植代替自体骨移植来修复上颌牙槽沟。少

The purpose of this study was to find out whether allogeneic bone grafts can repairthe alveolar cleft instead of autogenous bone grafts. The followings are the steps carried in the experiment 1. An animal model for maxillary alveolar clefts using rats.For operative procedures, an incision was made through the tissues of the palate and the oral mucosa was raised to expose the premaxilla. A circular hole was cut using a trephane in a dental handpiece.One hole with diameter of 2mm was prepared in the midline of premaxilla just posterior to the upper incisors. The defects were allowed to fill with blood clot , and overlying soft tissues were repaired. Postoperatively, the animals continued to feed satifactorily. No bony healing was seen in the cavities radiographically and histologically on 35 days-postoperation.2. Bone induction through the demineralized bone matrices in an animal model for maxillary alveolar clefts. Allogeneic bone grafts were placed into the maxillary alveolar clefts in … More rats using demineralized bone powder prepared from long bone of rats according to Reddi et al. New bone formation was seen in the cavities radiographically and histologically, on 21 and 35 days-postoperation.3. Bone induction of demineralized bone matrices stimulated by electromagnetic fields using an animal model for maxillary alveolar clefts in rats. Rats with allogeneic bone grafts into maxillary alveolar cleft were exposed to pulsed electric magnetic fields (PEMFs which were generated by pulsating currents in the coils of a 1 msec burst of opposite polarity repeating at 15 Hz. Pallets of bone grafts in rats exposed to PEMFs were stimulated on alkaline phosphatase activity, <^(45)Ca> incorporation.It was demonstrated that bone inductive activity of demineralized bone matrices were stimulated by electromagnetic fields. Therefore, we conclude that clinically we may be able to use allogeneic bone grafts stimulated by electromagnetic fields into maxillary alveolar clefts instead of autogenous bone grafts. Less