Objective Evaluation of the discoloration of traumatized deciduous teeth using the laser flowmeter and color difference meter

我们使用色差计和透射式激光流量计来客观地评估创伤牙齿的牙冠颜色和牙髓血流的变化。以下是我们发现的总结。使用色差计：1)即使采取了光学矫正措施，也很难从照片或肉眼中诊断出牙冠颜色；2)创伤引起的牙冠变色不均匀；3)通过肉眼检查对受伤牙齿的诊断是不合适的，因为大体临床表现与牙冠颜色的变化没有相关性；4)牙冠颜色的变化先于相应的放射表现；5)放射学结果的变化与牙冠颜色的变化有关；6)变色的牙齿可能会发生脱色和恢复原来的牙冠颜色；7)牙冠表面弯曲较大的尖牙和其他牙齿的测量误差较大；8)改装色差计可以评估深层组织的颜色，但与浅组织的结果没有明显差异。使用激光流量计：9)在其他方法不可能的情况下，可以在创伤后立即进行测量；10)该技术在评估牙髓活力方面非常有效；11)改装探头使可操作性得到改善；12)测量值有轻微的日内变化；13)乳牙根部的状况对产生的波形没有影响；14)恒牙牙根的状况导致产生的波形不同；15)流量计的结果受牙冠厚度和牙髓形态的影响；16)患者的合作对于获得稳定的测量结果是必不可少的。

We used a color difference meter and transmission-type laser flowmeter to objectively evaluate changes in crown color and pulpal blood flow in traumatized teeth. The following is a summary of our findings.Using the color difference meter :1) It is difficult to diagnose crown color from photographs or with the naked eye, even when optical corrective measures are taken ;2) Trauma-induced crown discoloration is not uniform ;3) Diagnosis by visual inspection of the injured tooth is inappropriate because gross clinical findings are not correlated with changes in crown color ;4) Changes in crown color precede the corresponding radiological manifestations ;5) Alterations in radiological findings were associated with changes in crown color ;6) Descolorization and restoration of original crown color may occur for discolored teeth ;7) Measurement error is appreciable for the canines and other teeth with steep curvature of the crown surface ;8) Modification of the color difference meter enabled the color of deep tissue to be assessed, but no major differences from the findings for shallow tissue were evident.With the laser flowmeter :9) Measurements can be made immediately post-trauma in cases where it is not possible by other means ;10) The technique is extremely effective in assessing pulp vitality ;11) Modification of the probe led to improved operability ;12) Slight intraday variations are seen in measured values ;13) The condition of the roots of deciduous teeth had no influence on the waveforms produced ;14) The condition of the roots of permanent teeth yielded differences in the waveforms produced ;15) Flowmetry findings are affected by crown thickness and pulp morphology ;16) Patient cooperation is essential for obtaining stable measurements.