Tsolakis A I, Spyropoulos M N
Department of Orthodontics, University of Athens, Greece.
Eur J Orthod. 1997 Feb;19(1):1-7. doi: 10.1093/ejo/19.1.1.
Many animal experiments dealing with function-form interaction and mandibular condylar growth have utilized hyperpropulsion of the animal's mandible. Numerous hyperpropulsive appliances have been described in the literature. However, there are significant discrepancies between reported results which are most likely due to the use of appliances that do not secure true mandibular hyperpropulsion. The specific rat craniofacial anatomy as well as the masticatory physiology of this animal requires the design of a specific appliance that would meet the species' functional characteristics. The aim of this paper is to describe a new type of appliance that can produce a controlled, stable and reproducible anterior displacement of the mandible in rats. After reviewing and evaluating the appliances used by other researchers, a totally new appliance for experimental mandibular hyperpropulsion in rats is presented. Its advantages are: (i) it produces a secure, measurable and reproducible anterior displacement of the mandible; (ii) it does not permit any retrusive or lateral mandibular movements. Avoidance of this variable can increase reliability of results and minimize involvement of other confusing parameters; and (iii) it allows the animals to be fed sufficiently for a number of hours every day. The appliance consists of an acrylic collar brace fitted to the animal's neck and carrying wire extensions that support rubber bands pulling on a band cemented to the animal's lower incisors. The pulling force depends on the thickness of the applied elastics.
许多涉及功能-形态相互作用和下颌髁突生长的动物实验都采用了动物下颌的过度前伸。文献中描述了许多过度前伸矫治器。然而，报告结果之间存在显著差异，这很可能是由于使用的矫治器不能确保真正的下颌过度前伸。大鼠特殊的颅面解剖结构以及该动物的咀嚼生理机能要求设计一种符合该物种功能特征的特定矫治器。本文的目的是描述一种新型矫治器，它能使大鼠下颌产生可控、稳定且可重复的前移位。在回顾和评估了其他研究人员使用的矫治器后，提出了一种全新的用于大鼠实验性下颌过度前伸的矫治器。其优点如下：（i）它能使下颌产生安全、可测量且可重复的前移位；（ii）它不允许下颌有任何后缩或侧向运动。避免这种变量可以提高结果的可靠性，并将其他干扰参数的影响降至最低；（iii）它允许动物每天有几个小时能充分进食。该矫治器由一个安装在动物颈部的丙烯酸项圈支架组成，支架带有钢丝延伸部分，钢丝延伸部分支撑着橡皮筋，橡皮筋拉动粘在动物下切牙上的带子。拉力取决于所使用弹性材料的厚度。
