DNA extraction and sex determination for human teeth dated 3000 years ago unearthed in Xi'an / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To extracted DNA from ancient human teeth dated 3000 years ago unearthed in Xi'an and determine the genders for the individuals.</p><p><b>METHODS</b>Thirty five ancient human teeth were studied. A 'Reverse-root-canal' technique and a Chelex-100 solution were used to extract the DNA. Specific primers for Amelogenin gene were designed for PCR amplification.</p><p><b>RESULTS</b>Genomic DNA was successfully extracted from 30 samples, for which 8 were determined to be males and 22 were females.</p><p><b>CONCLUSION</b>The 'Reverse-root-canal' technique may be used for extracting DNA from ancient human teeth. Genetics method can supplement physical anthropology for determination of sex for ancient samples.</p>

Study of alveolar bone defects reparation by combination of bone marrow stromal cells and fibrin glue / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To explore the effects and feasibility of the repairing alveolar bone by combination of bone marrow stromal cells (BMSCs) and fibrin glue (FG).</p><p><b>METHODS</b>BMSCs were obtained from the sucking mouse and then separated, cultured to the second generation to get ready for use. The available cells were combined with FG and then immediately implanted into the defect that had been established in one lateral maxilla of 30 SD rats. At the same time pure FG without BMSCs was implanted into the other side. The rats were killed at the 3rd and 6th week after operation. The hematoxylin-eosin staining and Micro-CT were used to observe and evaluate the osteogenesis.</p><p><b>RESULTS</b>New bone trabecula formed at experiment side of the rats at 3rd week. The repairing seemed better after 6th week of operation than the control side. There were only fibrous tissues in the control side or none.</p><p><b>CONCLUSION</b>This experiment showed a feasible approach of repairing the defects in alveolar bone of the rats.</p>

Dental caries found in the human skull of Tang dynasty excavated fron Xi'an / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the status of dental caries in the human of Tang dynasty.</p><p><b>METHODS</b>All teeth in 62 human skulls of Tang dynasty excavated from the Chang'an county in Xi'an city were examined and analyzed by statistics. The difference of prevalence in different group including age, sex and tooth position was tested with Chi-square test.</p><p><b>RESULTS</b>The prevalence of dental caries was 62.9%. And there were 92 caries teeth, which was 14.6% of the whole teeth. The root caries (33.3%) was more than the occlusal caries (28.7%). The most frequent recorded caries were the third molar, followed by the second molar, then the first molar. There was no significant difference between male and female.</p><p><b>CONCLUSIONS</b>The dental caries was popular in human of Tang dynasty, but the prevalence lowers than the modern people. And with the human evolution and the improvement of the social productivity, the prevalence of dental caries was gradually ascending.</p>