Anomalies of the cervical vertebrae in patients with skeletal Class II malocclusion and horizontal maxillary overjet.

INTRODUCTION

Cervical column morphology was examined in adult patients with skeletal Class II malocclusion and horizontal maxillary overjet; the findings were compared with cervical column morphology in an adult control group with neutral occlusion and normal craniofacial morphology. This has not previously been investigated.

METHODS

The overjet group consisted of 34 patients: 28 women (ages, 18-42 years) and 6 men (ages, 18-38 years). Their horizontal overjets ranged from 5.47 to 15.29 mm. The control group consisted of 21 subjects: 15 women (ages, 23-40 years) and 6 men (ages, 25-44 years). A visual assessment of the cervical column was made, and craniofacial dimensions were measured on each subject's profile radiograph.

RESULTS

In the overjet group, 52.9% had fusion of the cervical column, and 5.9% had posterior arch deficiency. Fusions occurred significantly more often in the overjet group compared with the control group (P <.01). Associations were found between fusions of the cervical column and mandibular retrognathia (P <.05), large cranial base angle (P <.05), and large horizontal overjet (P <.05).

CONCLUSIONS

The results could provide a new method to phenotypically subdivide skeletal maxillary overjets. This is important for the diagnosis and the correct treatment of these patients.