1 Faculty of Odontology, Malmö University , Malmö , Sweden.
2 Department of Oral Medicine and Radiology, Faculty of Dentistry, Sebha University , Sebha , Libya.
Dentomaxillofac Radiol. 2019 Jul;48(5):20180368. doi: 10.1259/dmfr.20180368. Epub 2019 Feb 28.
To evaluate measurability and reliability of measurements of root length and marginal bone level in CBCT, periapical (PA) and bitewing (BW) radiographs.
CBCT of both jaws, PA of maxillary incisors and posterior BW radiographs of 10 adolescents (mean age 13.4) were selected. The radiographs comprised part of the baseline examinations of a trial of orthodontic treatment. Six raters assessed measurability and measured root length and marginal bone level. Three raters repeated their assessments. Measurability was expressed as frequency of interpretable sites and reliability as intraclass correlation coefficient (ICC).
Measurability was 100 % in CBCT and 95 % in PA of maxillary incisors for root length measurements. For marginal bone level, measurability was 100 % in CBCT, 76 % in PA and 86 % in posterior BW. Mean ICC for interrater reliability for root length measurements in CBCT was 0.88 (range 0.27-0.96 among different teeth) and 0.69 in PA of maxillary incisors. For marginal bone level measurements, mean ICC was 0.4 in CBCT, 0.38 in PA of maxillary incisors and 0.4 in posterior BW. Intrarater reliability varied among methods, root length or marginal bone level and among raters, except for root length measurements in CBCT, which presented high reliability (above 0.8) for all raters.
As measurability and reliability were high for root length measurements in CBCT, this may be the method of choice for scientific analyses in orthodontics. For clinical praxis, we recommend PA following the "as low as diagnostically acceptable" principle, as clinical decisions seem to be influenced only when severe root resorption occurs.
评估 CBCT、根尖（PA）和牙合翼（BW）片上根长和边缘骨水平测量的可测量性和可靠性。
选择了 10 名青少年（平均年龄 13.4 岁）的上下颌 CBCT、上颌切牙的 PA 和 10 颗磨牙的 BW 片。这些射线照片是正畸治疗试验基线检查的一部分。六名评估者评估了可测量性并测量了根长和边缘骨水平。三名评估者重复了他们的评估。可测量性表示为可解释部位的频率，可靠性表示为组内相关系数（ICC）。
根长测量的 CBCT 可测量性为 100%，上颌切牙的 PA 为 95%。对于边缘骨水平，CBCT 的可测量性为 100%，PA 为 76%，BW 为 86%。CBCT 中根长测量的组间可靠性的平均 ICC 为 0.88（不同牙齿之间的范围为 0.27-0.96），上颌切牙的 PA 为 0.69。对于边缘骨水平测量，平均 ICC 为 0.4，PA 为 0.38，BW 为 0.4。除了 CBCT 中的根长测量外，不同方法、根长或边缘骨水平以及不同评估者之间的组内可靠性均存在差异，CBCT 中的根长测量具有较高的可靠性（均高于 0.8）。
由于 CBCT 中根长测量的可测量性和可靠性较高，因此这可能是正畸学中科学分析的首选方法。对于临床实践，我们建议遵循“尽可能低以达到诊断可接受的”原则进行 PA，因为临床决策似乎仅在发生严重根吸收时才会受到影响。
