Shafer D M, Rogerson K, Norton L, Bennett J
Department of Oral and Maxillofacial Surgery, University of Connecticut Health Center, Farmington 06030, USA.
J Oral Maxillofac Surg. 1995 Sep;53(9):1063-8. doi: 10.1016/0278-2391(95)90125-6.
Successful osseointegration of titanium dental implants is decreased in areas of poor bone volume and density. Low amperage direct current (LADC) has been shown to perturb bone cells, which in turn promotes bone growth. The purpose of this experiment was to evaluate the effect of LADC on the osseointegration of endosseous titanium dental implants.
Two implant sites were prepared in the body of the mandible of five rabbits by an extraoral approach. An LADC-stimulated 3.75 x 7 mm-titanium implant was placed in one site and an identical control implant was inserted on the contralateral side. A sterilized silicone-encased power pack producing 7.5 +/- 0.2 uA and 1.35 +/- 0.01 V was placed in a submandibular pouch. The active cathode lead was attached to the LADC implant and the anode was placed in the mandible 5 mm distal to the implant. Nonactive leads were similarly connected to the control implant. Twenty-eight days after placement, the implants were removed using a torque wrench, and the bone surrounding the implants was examined both microscopically and radiographically.
The average force to initial rotation was 1,320 +/- 880 g/cm for the LADC-stimulated implants and 1,290 +/- 238 g/cm for the control implants. This was significantly different by t test (P = .94). Light microscopic evaluation demonstrated a mixture of compact and woven bone and fibrous tissue adjacent to both groups of implants. Histomorphometric analysis demonstrated an average percent of bone in relation to the total tissue adjacent to the control implants of 33.5 +/- 15.4 and 40.2 +/- 4.8 for the LADC-stimulated implants (not significantly different, t test, P = .39). CONCLUSION. It was concluded that LADC as used in this study does not positively affect the healing of bone. Its ability to enhance bone growth around titanium dental implants needs further investigation.
在骨量和骨密度较差的区域，钛牙种植体的成功骨整合会降低。低安培直流电（LADC）已被证明会干扰骨细胞，进而促进骨生长。本实验的目的是评估LADC对骨内钛牙种植体骨整合的影响。
通过口外入路在5只兔子的下颌骨体内制备两个种植部位。将一个经LADC刺激的3.75×7毫米钛种植体植入一个部位，并在对侧植入一个相同的对照种植体。一个产生7.5±0.2微安和1.35±0.01伏的无菌硅胶封装电源组置于下颌下袋中。活性阴极导线连接到LADC种植体，阳极置于种植体远端5毫米处的下颌骨中。非活性导线以类似方式连接到对照种植体。植入28天后，使用扭矩扳手取出种植体，并对种植体周围的骨组织进行显微镜和放射学检查。
LADC刺激的种植体初始旋转平均力为1320±880克/厘米，对照种植体为1290±238克/厘米。经t检验，这一差异具有统计学意义（P = 0.94）。光学显微镜评估显示，两组种植体相邻处均有致密骨、编织骨和纤维组织的混合物。组织形态计量学分析显示，对照种植体相邻总组织中骨的平均百分比为33.5±15.4，LADC刺激的种植体为40.2±4.8（t检验，差异无统计学意义，P = 0.39）。结论：本研究中使用的LADC对骨愈合没有积极影响。其增强钛牙种植体周围骨生长的能力需要进一步研究。
