The Study Of Oral Diseases In Skulls Excavated From The Site About 2,200 Years Ago In China

People's oral disease was an old disease, which was continually variational as the people's evolvement. In order to prevent the damage of oral disease to people's bodies, scholars researched the disease continually, so that they could find the rule of the appearance and development of oral disease and control it. But the data about the development of oral disease were absent and insufficient. There was none report about the oral disease of Chinese about two thousands years ago. The famous site of Emperor QinShihuang's Mausoleum and Terra-Cotta Warriors and Horses was in the Xi'an city, Shaanxi Province of China. Some of the people who built it were also buried here. In February 2003, 113 skeletons about 2,200 years ago were excavated from this site by Shaanxi Archaeological Institute and Institute of Archaeology of Chinese Academy of Social Sciences. They were all male, whose age between 15 and 45 years old. It was uncommon that so many skulls were excavated in one place and in one time in the archaeological field. The material was costful for us to study the people's living.Our study used the method of cross-sectional study of descriptiveepidemiology. The prevalence rate of oral disease in the 113 skulls could be summarized in our detailed report. The study aimed to describe the status of oral disease in people about two thousands years ago. Compared the epidemiologic data in different eras, we could found the rule and trend of oral disease in people.After collecting and cleaning up the whole objects, we numbered the skulls and labeled the position of all the teeth in the jaws. Every kind of diseases was noted detailedly according to the latest and authoritative clinical diagnosis standards and method, In order to find the relation between the oral disease and age, the objects were divided into three groups according to their age. The data were dealt with by statistical methods. The results were discussed and showed as follows.In the aspect of malocclusion, the prevalence rate of malocclusion was 50.70 per cent. The malocclusion lied in 36 persons. The prevalence rate of deep overbite, distoclusion and mesioclusion were highest. They were all 18.31 per cent. The prevalence rate of lock bite was lowest, which was 1.41 per cent. 9.86 per cent objects were found having crowding in the jaws, while 4.22 per cent objects had clearance. The prevalence rate of retained deciduous teeth, microdontia and supernumerary teeth were 3.54 per cent, 4.42 per cent and 0.88 per cent respectively. There were 23.01 per cent objects having congenital missing teeth, nearly all of them being the third molar.In the aspect of dental caries, the prevalence rate of dental caries was 47.12 per cent. There were 156 decayed teeth in 49 objects, which were 6.36 per cent in the whole teeth. The mean DMFT was 1.50. The prevalence rate of dental caries rose with the rise of people's age. Among the proportion in the whole teeth, the second molar was the highest (28.20 per cent) and the caninewas the lowest (0.00 per cent) according to the tooth position, while the interproximal caries was the highest (55.10 per cent) and the lingual caries was the lowest (0.68 per cent) according to the tooth surface. In the group that was above 30 years old of age, the proportion of root cavity (23.08 per cent) was more than that of other groups. The medium caries was the most common (65.38 per cent) in the whole decayed teeth. 8.97 per cent teeth appeared periapical periodontitis as the caries became more serious.In the aspect of periodontal disease, there were 343 teeth in 51 objects having the periodontal disease, which was 13.99 per cent in the whole teeth. The prevalence rate of periodontal disease was 49.04 per cent. The proportion of patients and teeth having periodontal disease was ascending with the age in every group.The proportion of the first molar was the highest (36.15 per cent) and the central incisor was the lowest (5.25 per cent) among the teeth which had the periodontal disease.In the aspect of tooth attrition, amost all of teeth wear away. The attrition in symmetrical tooth position was almost the same. The first molar has the most serious tooth wear (2.59±1.02) and the third molar was the lightest (0.86±0.60). There was not observably different in the attrition of the first molar, canine and central incisor (p<0.05). The tooth wear increased with age. In the whole attrited teeth, the proportion of score 2 was highest (43.16 per cent), and the score 4 was the lowest (5.15 per cent).As the above showed, many kinds of oral disease including the malocclusion were common in the people about two thousand years ago. Not only the prevalence rate of dental caries and periodontal disease, but also the tooth attrition increased with age. Comparing the modern people, the prevalence rate of malocclusion and dental caries in the people in that time...