The validity of the cervical vertebral maturation staging method as a biological indicator to determine mandibular growth spurt

Abstract

BACKGROUND: In the orthodontic treatment of patients with skeletal discrepancies during adolescence, craniofacial growth is often of prime importance to reach a successful treatment. The ultimate goal would be the ability to accurately predict the onset, duration, and magnitude of the peak pubertal growth spurt, particularly in relation to the mandible. The features of the cervical vertebrae, on the lateral cephalogram have been investigated to identify the stage of growth and development and predict both the timing of onset and potential of growth. Although previous studies have researched the relationship between CVM and mandibular growth and concluded that, the CVM method is a valid indicator for the assessment of skeletal maturity, there have been conflicting reports regarding its accuracy and validity. Thus, the aim of this study was to determine the diagnostic value of the Cervical Vertebral Maturation method in determining the time of the mandibular growth spurt based on data from various databases with a larger sample size.

MATERIALS & METHODS: A total of 796 cephalometric films from 113 subjects from various databases were collected, printed and traced. Measurements of mandibular length, (from condyle to gnathion), ramus height (from condyle to gonion) and from gonion to gnathion were made. For each subject, mandibular length (Co-Gn) was measured for each film, and the growth increment between films was calculated. For each subject, the film displaying CVM stage 3 was identified by three orthodontists. Diagnostic tests, including sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were carried out.

RESULTS: Overall sensitivity for CVM stages 3 was very low being no greater than 40%. On the contrary, the specificity was more than 70%. The CVM stage 3 in the identification of mandibular growth peak, yielded a diagnostic accuracy of more than 50%. The overall PPVs were unsatisfactory with values not greater than 40% on the contrary, the overall NPVs were high with values of at least 60%.

CONCLUSIONS: CVM stages 3, did not reach satisfactorily diagnostic reliability in the identification of imminent mandibular growth peak.