Development of a Monitor System for Orthodontic Tooth Movement

本研究旨在开发一种基于光学测量牙周膜血流量的正畸牙齿移动监测系统。应用近红外光谱技术测定实验性牙齿移动过程中牙周膜中总血红蛋白和氧合血红蛋白的含量。对猫上颌尖牙施加25、50、100、250g的正畸力，共28天。在正常牙周膜中，总血红蛋白由于施加于牙冠的负荷而降低，而氧合血红蛋白没有变化。在25g的正畸力作用下，牙周膜的血流反应与正常牙周膜基本相同.在50g和100g的正畸力作用下，总血红蛋白和氧合血红蛋白的变化是一致的.在250g的正畸力作用下，牙周膜的总血红蛋白和氧合血红蛋白无血流反应。50g和100g的正畸力样本比其他样本显示更快的牙齿移动。组织学观察表明，这种方法是有用的，在确定最佳力的基础上的数据在PDL的代谢活动。在临床应用之前，测量系统配备了半导体激光器作为光源。在人类牙周膜没有正畸力施加，血流反应几乎是相同的动物样本。

This study was conducted to develop a monitor system for orthodontic tooth movement based on optical measurement of blood volume in periodontal ligaments (PDL). Near infrared spectroscopy was applied to measure total-hemoglobin and oxy-hemoglobin in PDL during experimental tooth movement. Orthodontic force (25g, 50g, 100g, 250g) was applied to the maxillary canine of cats for 28 days.The results were :1. In normal PDL.total-hemoglobin decreased due to the application of load to a tooth crown, while oxy-hemoglobin was unchanged.2. With a 25g orthodontic force, the blood flow response of PDL was almost the same as the normal PDL sample.3. With the 50g and 100g orthodontic force, the changes both in total-hemoglobin and in oxy-hemoglobin were remarkable.4. With a 250g orthodontic force, there was no blood flow response of PDL in total-hemoglobin and oxy-hemoglobin.5. The 50g and 100g orthodontic force samples showed more rapid tooth movement than the others.6. Histological observation suggested that this method was useful in determining the optimal force based on the data for the metabolic activity in PDL.Prior to the clinical application, the measurement system was equipped with a semiconductor laser as a light source. In human PDL without orthodontic force applied, the blood flow response was almost the same as the animal samples.