Gröndahl K, Sundén S, Gröndahl H G
Department of Oral Diagnostic Radiology, Faculty of Odontology, Göteborg University, Sweden.
Clin Oral Implants Res. 1998 Aug;9(4):243-50. doi: 10.1034/j.1600-0501.1998.090405.x.
The aim was to determine inter- and intraobserver variability in radiographic bone level assessments at Brånemark fixtures and to study the influence of various factors (radiographic density; projection geometry; jaw in which the fixtures were inserted; degree of bone loss; time after fixture loading; and number of radiographs of each fixture) on the variability. Intraoral radiographs from bridge connection and 1- and 3-year check-ups from 15 upper and 15 lower jaws (172 fixtures) were assessed by 6 observers. Measurements were taken from a reference point on the fixture to the marginal bone level, and some were repeated by all observers after 1 months. Results showed a small interobserver variation (0.14 mm) with the intraobserver variation (0.08 mm) as its largest component. The radiographic density and the degree of bone loss showed the strongest influence on the interobserver variation. The only variable with a significant effect on the intraobserver variation was the number of radiographs of each fixture. Calculated confidence values showed that measurement reliability can be improved by letting one observer or preferably more make several, independent readings, allowing for the demonstration of minor differences in bone height over time or between implant systems.
目的是确定在布兰emark种植体上进行放射学骨水平评估时观察者间和观察者内的变异性，并研究各种因素（放射密度；投影几何形状；种植体植入的颌骨；骨吸收程度；种植体加载后的时间；以及每个种植体的放射照片数量）对变异性的影响。6名观察者对来自15例上颌和15例下颌（172枚种植体）的桥接连接以及1年和3年检查的口腔内放射照片进行了评估。测量从种植体上的一个参考点到边缘骨水平，并且所有观察者在1个月后重复了一些测量。结果显示观察者间变异较小（0.14毫米），其中观察者内变异（0.08毫米）为最大组成部分。放射密度和骨吸收程度对观察者间变异的影响最强。对观察者内变异有显著影响的唯一变量是每个种植体的放射照片数量。计算出的置信值表明，通过让一名观察者或最好多名观察者进行多次独立读数，可以提高测量可靠性，从而能够显示出随时间推移或不同种植体系统之间骨高度的微小差异。
