El-Bialy T H, Elgazzar R F, Megahed E E, Royston T J
Orthodontics and Biomedical Engineering, Faculty of Medicine and Dentistry, University of Alberta, Dentistry/ Pharmacy Centre, Edmonton, AB, Canada.
J Dent Res. 2008 Oct;87(10):953-7. doi: 10.1177/154405910808701018.
Previous studies have shown that therapeutic pulsed ultrasound (pulsed) has superior stimulatory effect on bone fracture healing compared with continuous ultrasound (continuous). Our predictive hypothesis was that pulsed ultrasound can produce better bone formation during mandibular osteodistraction than continuous ultrasound. Thirty-six New Zealand rabbits were divided into 3 groups of 12. Osteodistraction was performed at 3 mm/day for 5 days. Group 1 received pulsed, group 2 received continuous ultrasound, and group 3 was the control group (distraction only). Bone formation was assessed by quantitative bone density (QBD), mechanical testing, and histological examination. In the first 2 wks post-distraction, group 2 showed enhanced bone formation more than group 1 (p < 0.05); however, in the 3rd and 4th wks, group 1 showed more bone formation than group 2 (p < 0.05). Earlier stages of bone healing were enhanced more by continuous, whereas late stages were enhanced more by pulsed, ultrasound.
先前的研究表明，与连续超声（continuous）相比，治疗性脉冲超声（pulsed）对骨折愈合具有更好的刺激作用。我们的预测性假设是，在下颌骨牵张成骨过程中，脉冲超声比连续超声能产生更好的骨形成。36只新西兰兔被分为3组，每组12只。以每天3毫米的速度进行牵张5天。第1组接受脉冲超声，第2组接受连续超声，第3组为对照组（仅牵张）。通过定量骨密度（QBD）、力学测试和组织学检查评估骨形成情况。在牵张后的前2周，第2组的骨形成增强程度超过第1组（p < 0.05）；然而，在第3周和第4周，第1组的骨形成比第2组更多（p < 0.05）。连续超声对早期骨愈合的促进作用更强，而脉冲超声对晚期骨愈合的促进作用更强。
