The effect of head posture on muscle contact position using the T-Scan system of occlusal analysis

The purpose of this study is to investigate the effect of sagittal plane head-neck posture on initial tooth contacts (muscle contact position) using the T-Scan system of occlusal analysis. Thirty-five subjects from 14 to 72 years old were selected. Computerized T-Scan occlusal printouts were obtained on each subject with the head-neck in 45 degrees dorsiflexion and 30 degrees ventroflexion. To quantify the location of the contacts on the upper arch, the dotted lines appearing on the printout were assigned numerical values. Low numbers represent distal contacts and the higher the number, the more mesial the contact. Wilcoxon's Rank Sum Test was used to analyze the data. Results indicated that below the age of 30 years no significant relationship was demonstrated between head posture and muscle contact position. However, over the age of 30 there was an increasingly significant relationship between sagittal plane head-neck posture and initial occlusal contacts. Based on these findings, the authors recommend that management of occlusally related problems, i.e., temporomandibular disorders include an assessment of the craniovertebral region especially in patients over the age of 30 years.