ABSTRACT
We wanted to assess and compare the morphological deviations of the cervical vertebral column and cranial base angle in three different facial types that is hypodivergent, normodivergent and hyperdivergent groups and elucidate the aetiology behind the associations as well as clinical implications of the results. MethodsThe study was conducted in the department of orthodontics wherein lateral cephalograms of 150 subjects in the age group of 18 - 25 years were taken and divided into three groups. The division of groups was made as per Steiner’s mandibular plane angle i.e. Hyperdivergent group (SN–MP angle >34 degrees) Normodivergent group (SN–MP angle 26- 34 degrees) Hypodivergent group (SN–MP angle < 26 degrees). Lateral cephalograms were traced and analysed to compare the variables by statistical analysis. Morphology of the cervical column was evaluated by visual inspection of the first 5 cervical vertebrae as they are normally seen on a standardized lateral skull radiograph. Characteristics of the cervical column were classified according to the method of Sandham. The cranial base angle was measured by the angle between nasion sella and sella basion (N-S-Ba) and then compared in the three groups. ResultsThe cranial base angle was increased significantly in the hyperdivergent group and decreased in the hypodivergent group when compared to the normodivergent group patients. However, no significant results were associated regarding the morphology of the cervical column in the three groups. ConclusionsAssociations between the cranial base angle and cervical column morphology plays a pivotal role in orthodontics in making the diagnosis of malocclusion and finding out the pattern of growth in vertical direction. A routine examination of the cervical vertebral column area for any deviation in the morphology should be done and checked. These registrations may prove useful in making the diagnosis and finding aetiology especially in the cases of severe skeletal malocclusions like severe open bite and deep bite and those with obstructive disorders like obstructive sleep apnoea or enlarged adenoids.