Curvature of cervical vertebra in 8020 achievers observed by lateral cephalogram.

The hypothesis of this research was that elderly people with many remaining teeth and good occlusion (8020 achievers) would be able to maintain proper head and body posture, despite aging. The purpose of this study, as a first stage, was to clarify the aging phenomenon of cervical curvature in 8020 achievers in comparison with that in young adults. Subjects consisted of twenty-eight 8020 achievers, with a mean age of 82.96+/-3.3 years and 26.5+/-4.0 teeth. For comparison, forty adults in their 20's with a mean age of 22.9+/-0.7 years and 28.2+/-0.6 teeth were also enrolled. The cervical vertebra was assessed based on the distance from the CV line (tangential line of the 2nd and 6th cervical vertebra) to each cervical vertebra and the angles formed by the cervical and reference lines in the cranial bone. Every distance from the CV line to each cervical vertebra in the 8020 group was bigger than that in the 20's group (p<0.01-0.001). The distance from the CV line to CV-3 and CV-5 in 8020 women was larger than that in 8020 men (p<0.05). Every distance from the CV line to each cervical vertebra in 8020 women was larger than that in 20's women (p<0.01-0.001). There was no significant difference between 8020 men and 20's men. The difference between the women's group was more marked than that between age groups for men. The cervical curvature in 8020 achievers showed a greater tendency toward cervical lordosis than that in young adults. In the 8020 achievers, the curvature in women was greater than that in men. The curvature in 8020 women seemed was marked, showing strong cervical lordosis, despite the presence of many remaining teeth and good occlusion. It remains to be determined by comparing 8020 achievers with ordinary elderly whether the condition of the teeth influences spinal curvature with aging.