The relationship between cervical column curvature and sagittal position of the jaws: using a new method for evaluating curvature

Abstract

Background: For determining the cervical column curvature, the curve fitting method is the most precise method, but using this method in clinic seems to be difficult if not possible. In this study, we used a modification of cervical column inclination angle that has been already mentioned

Objectives: The aim of this study was to evaluate the posture and curvature of the cervical column introducing a modified constructed angle in order to evaluate the cervical column curvature in a relax position in relation to the jaws sagittal position.

Patients and methods: The lateral cephalometries of patients with no anomaly were taken in the natural head position. The mean age of the patients was 13.49 years including 56 female and 44 male. Steiner and Wits analysis was used to evaluate the sagittal position of the jaws. Modified constructed CVT/HOR and OPT/HOR angles were used to evaluate the cervical column posture and curvature. Patients were classified into three groups according to the angle's classification.

Results: The results showed a significant positive correlation between modified constructed angles and sagittal jaw relationships (P < 0.05). Besides, in class II patients, there was a significant correlation between OPT/HOR and parameters ANB and Wits (P < 0.05 and P < 0.01, respectively). Age could not affect the curvature and posture of the cervical column.

Conclusions: According to the result of this study using modified constructed angles may be a simple method for evaluation of the relation between cervical column curvature and sagittal position of the jaws. There is significant correlation between cervical column posture angles and parameters ANB and Wits in Cl. II patients.

Keywords: Cervical Vertebrae; Dental Occlusion; Jaw Relation Record.

Figure 1. The Illustration Shows Schematic Method of a Traced Cephalometry.

S, Sella turcica; N, Nasion; Gn, Gnathion; Go, Gonion; Ar, Articular; Ba, Basion; CV2SP, The most superior posterior point of CV2; CV2IP, The most inferior posterior point of CV2; CV4IP, The most inferior posterior point of CV4; CVT, The posterior tangent line to odontoid process that passes CV2SP and CV4IP; OPT, The posterior tangent line to odontoid process that passes CV2SP and CV2IP

Figure 2. The Gragh Shows the Method of Phi (Ф) Angle Calculation.

P0, The beginning point of the path; S, The length of the path; P; The end point of path; T, The tangent line on the curve at point P; Ф, The angle between T and true horizontal