This study was performed to investigate the morphological and positional correaltion between the upper cervical vertebra, the oral structures and the pharyngeal tissues, and the correlation of these anatomical structures with dental features, such as ...
This study was performed to investigate the morphological and positional correaltion between the upper cervical vertebra, the oral structures and the pharyngeal tissues, and the correlation of these anatomical structures with dental features, such as teeth wear area and tooth contact status, etc Seventy patients with temporomandibular disorders and sixty three dental students without any signs and symptoms in head and neck region were selected for this study. All they had natural dentition without any fixed and removable prostheses. Teeth wear area and arch width were measured from the upper dental cast, tooth contact status were observed by T-Scan system(r) and four cephaloradiographs were taken from four head postures, namely, natural(NHP), forward(FHP), upward(UHP), and downward head posture(DHP). 22 cephalometric items were measured on the films and the data were processed with SAS statistical program. The result of this study were as follow.
1. In normal group, angle of cervical vertebra tangent and of between hard and soft palate were broader in female subjects than those in male subjects, but distance from subocciput to axis, size of soft palate, and pharyngeal space width were larger in male subjects.
2. In normal group with natural head posture, the items correlated each others from the three anatomical regions were distance between first and second vertebra in posterior part, distance from the lingual surface of lower anterior teeth to anterior surface of soft plate, and distance from the hyoid bone to third vertebra.
3. Three set of items showed significant correlation each other in the four head postures in normal group First set was the angle between hard and soft palate and the distance from subocciput to posterior arch of first vertebra, second set was the distance between first and second vertebra in posterior part and the teeth wear area, third set was number and force of tooth contact and length of soft palate and distance from anterior tip of hyoid bone to mandibular plane.
4. There was a tendency that the pharyngeal space area were increased in FHP and in UHP, decreased in DHP