Comparing the reproducibility of CVMs (cervical verteberae maturation stage) with and without consedring the shape of the cervical verteberae

Abstract

Introduction: Timing of treatment could be as important as treatment plan. Cervical vertebrae morphology varies with growth. Since, the cervical vertebrae are visible in the lateral cephalograms which orthodontists typically use and does not need extra exposure to x-ray, assessment of skeletal age from cervical vertebrae maturation (CVM method), is a reliable method. Recently, the reproducibility of this method has been questioned. As the method of CVMS is based on observer’s capability to determining the morphologic properties of cervical verteberaes, then the poor or high reproducibility of this method is related to reproducibility of determining the shape and the curvature of the vertebrae’s lower border. It seems that reviewing and modifying the attitude in the shape of vertebrae can lead to increasing the reproducibility and improvement of the method’s quality. So, in this study we are going to investigate the reproducibility of CVMS by modifying the original method. Method & materials: 10 orthodontists with a long clinical practice and experience in the CVM method rated twice cervical vertebrae maturation with the CVM original Baccetti’s method on 70 cropped scans of lateral cephalograms of children in circumpubertal age (9 to 15 years). Then The modification of method were presented to the observers to improve the reproducibility of the method observers rated twice the all previous cephalograms by modified method as well. Kappa statistics (with lower limits of 95% confidence intervals (CI)) and proportion of complete agreement on staging was used to evaluate intra- and inter-observer reproducibility.

Result: The inter-observer reproducibility of original method by CVMS was between 0.49-0.51, which according to Landis and Koch´s classification (47) is moderate. The reproducibility intra-observer was in range of 0.46-0.87 (mean: 0.67). The inter-observer reproducibility of modified method by not considering the shape of verteberae was between 0.59-0.62, which according to Landis and Koch´s classification (47) is moderate to substantial. The reproducibility intra-observer was in range of 0.76-0.03 (mean: 0.85). Also, the agreement in both methods increased from the first observation to the second observation by a small amount. Conclusion: in comparison to original Baccetti’s method, the reproducibility of modified CVMS (without considering the shape of verteberae) has been increased. Considering the length of the posterior and lower borders is good in place of the vertebrae.’s geometric shape.