Mooney M P, Losken H W, Siegel M I, Tsachakaloff A, Losken A, Janosky J
Department of Anatomy and Histology, University of Pittsburgh, PA 15261.
J Craniofac Surg. 1992 Dec;3(4):197-202. doi: 10.1097/00001665-199212000-00004.
It has been suggested that rigid fixation of the developing craniofacial skeleton may lead to altered craniofacial growth. However, recent experimental studies have shown that microplate fixation of slow-growing calvarial sutures resulted in regional growth disturbances but had little effect on overall craniofacial growth. The present study was designed to assess the effects of microplate fixation of the more rapidly growing facial sutures on compensatory midfacial growth in the rabbit. Twenty-two 1.5-week-old rabbits were randomly divided into 2 groups: sham controls (n = 11) and animals with bilateral premaxillomaxillary suture fixation (n = 11). Fixation was accomplished using an intraoral approach, a 6-mm straight Luhr microplate, and two 2-mm long self-tapping screws across each suture. Serial lateral head radiographs were collected at 1.5, 3.5, 6, 12, and 18 weeks of age. Results revealed that by 3.5 weeks, animals with rigid fixation showed significantly shortened premaxillary lengths (p < 0.05), class III occlusal relationships, decreased midfacial heights, and abnormal palatocranial base angles compared with sham control animals. By 12 weeks of age, "catch-up" growth was evident in most dimensions in animals with fixation compared with shams. Gross examination of the cleaned and dried skulls revealed bony bridging across the premaxillomaxillary suture and osseous fracture lines extending superiorly from the site of screw fixation. Results demonstrated that rigid fixation of a rapidly growing facial suture did not impair long-term midfacial growth in the rabbit model and suggest that compensatory changes may have occurred at fracture lines from the self-tapping screws in these animals.
有人提出，发育中的颅面骨骼的刚性固定可能会导致颅面生长改变。然而，最近的实验研究表明，对生长缓慢的颅骨缝进行微型钢板固定会导致局部生长紊乱，但对整体颅面生长影响不大。本研究旨在评估对生长较快的面部缝进行微型钢板固定对兔代偿性面中部生长的影响。将22只1.5周龄的兔随机分为2组：假手术对照组（n = 11）和双侧上颌前颌缝固定的动物（n = 11）。采用口内入路、一块6毫米直的卢尔微型钢板和两枚2毫米长的自攻螺钉穿过每条缝来完成固定。在1.5、3.5、6、12和18周龄时收集系列头颅侧位X线片。结果显示，到3.5周时，与假手术对照动物相比，刚性固定的动物上颌前长度显著缩短（p < 0.05），出现III类咬合关系，面中部高度降低，腭颅底角异常。到12周龄时，与假手术组相比，固定动物的大多数维度出现“追赶”生长。对清洁和干燥后的颅骨进行大体检查发现，上颌前颌缝处有骨桥形成，自攻螺钉固定部位有向上延伸的骨折线。结果表明，在兔模型中，对快速生长的面部缝进行刚性固定不会损害长期面中部生长，并提示这些动物自攻螺钉部位的骨折线可能发生了代偿性变化。
