Abstract

Background and Objective: Studies have documented that deviations in skeletal components such as the cranial base, the mid-facial complex and the mandible may be associated with morphological factors in patients with class III skeletal malocclusion. Furthermore, deviations in head and neck posture may be associated with the class III skeletal malocclusion. The purpose of this study was to compare cervical vertebrae morphology in patients with class III skeletal malocclusion and adults with normal occlusion. Materials and Methods: This case-control study assessed 30 patients with class III skeletal malocclusion (aged 17-30 yrs, with normal vertical growth pattern and ANB<0) were compared with 46 controls (aged 17-30 years, with normal vertical growth pattern, ANB=3+1). Cervical vertebrae anomalies (fusion anomalies and posterior arch deficiency) were assessed via evaluation of their lateral cephalograms. The t-test and Fisher's exact test were used for statistical analysis. Results: In the study group, 73.3 had fusion of the body of the cervical vertebrae, while in the control group only 32.6 showed fusion. The fusion in the control group was between C2 and C3 in all cases; whereas, in the study group, fusion was seen between C2-C3, C3-C4 or C4-C5. Additionally, cervical column deviations occurred significantly more often in the study group compared to the control group (P<0.001). Conclusion: Class III skeletal malocclusion may be associated with fusion of cervical vertebrae and deviation of the cervical column.