Pedersen E, Isidor F, Andersen K
Department of Prosthetic Dentistry, Royal Dental College, Aarhus, Denmark.
Eur J Orthod. 1994 Feb;16(1):41-6. doi: 10.1093/ejo/16.1.41.
An in vitro study was conducted to compare reproducibility of repeated recordings obtained from devices constructed for standardized registrations. An existing radiographic method and a new photographic technique were employed. On five in vitro models, half of the maxilla from dry skulls, special designed splints with a Troll-biten film holder were constructed. A stiff metal bar attached to the splints and to either an X-ray apparatus or a standard photographic camera made it possible to obtain standardized registrations. For each model 10 radiographs and photographs were taken before and after the canine was moved. Subtracting the values from well defined points for these pictures, 10 pairs of coordinates were available for each of the models with both methods. The findings showed very similar reproducibility for the two methods with 95 per cent of the discrepancies within a magnitude of 0.12 mm for the radiographic method and 0.14 mm for the photographic method. When evaluating the canine movements, similar results were observed. No significant difference could be detected in the five in vitro models. In addition, the results showed that a splint can be used as a stable reference for registration of tooth movements. Because of ethical objections to unnecessary radiation, the photographic registration technique might substitute the radiographs in future investigations where standardized periodic records are necessary for the description of tooth movement.
进行了一项体外研究，以比较从为标准化记录构建的设备获得的重复记录的可重复性。采用了现有的放射照相方法和一种新的摄影技术。在五个体外模型上，即干颅骨的上颌骨的一半，构建了带有Troll-biten胶片夹的特殊设计夹板。连接到夹板以及X射线设备或标准摄影相机上的一根刚性金属杆使得获得标准化记录成为可能。对于每个模型，在移动犬齿前后拍摄10张X光片和照片。从这些图片的明确定义点减去数值，两种方法对每个模型都有10对坐标。结果表明，两种方法的可重复性非常相似，放射照相方法95%的差异在0.12毫米范围内，摄影方法在0.14毫米范围内。在评估犬齿运动时，观察到了相似的结果。在五个体外模型中未检测到显著差异。此外，结果表明夹板可作为牙齿运动记录的稳定参考。由于对不必要辐射的伦理反对，在未来需要标准化定期记录来描述牙齿运动的研究中，摄影记录技术可能会替代X光片。
