Anatomical Crown Width/Length Ratios Of Worn And Unworn Maxillary Teeth In Shandong Province

Background:With the rapid development of Esthetic restoration in recent years, various aesthetic parameters of maxillary anterior teeth have become an increasing concern, the data of maxillary anterior teeth crown width, length and width/length ratio is very important. The related research in Chinese and abroad gradually increased, but the studies often uses the white’s data, researches of xanthoderm relatively are rare. But the difference of racial, ethnic, regional groups of maxillary anterior crown length, width and length width ratio is existed have been confirmed. Therefore, the aim of this study was to measure the population of Shandong province of the maxillary teeth length, width value and its standard width to length ratio values, in order to extend the kwkkanterior teeth, aestheticrestorative treatment, maxillary anterior teeth with the establishment and perfection of providing some reference and research results of the mouth of the other scholars were compared and discussed making Chinese ratiomeasuring scale and Chinese teeth database.Objective:The purpose of this study was to measure the population of Shandong area in maxillary anterior anatomical crown width, length and width to length ratio, the data from the studies of the local people to exercise the aesthetic crown lengthening for periodontal operation to determine the gum excision range,production and meet the aesthetic standards of the crown of anterior teeth lossand has a certain reference value. Method.287maxillary this study from Qilu Hospital of Shandong province providesisolated teeth (65incisors,67lateral incisors,39canine,116premolars).According to the anatomic position of tooth is divided into central incisors, lateral incisor, canine group and premolar groups and within each groupdivided into dental attrition and abrasion of teeth without dental attrition group,grouping criteria is the tooth end cutting a small plane, wear the obvious and can be observed in the exposed dentin. MR-14EX rings and then use the100mm micro lens Canon EOS550D camera flash. According to the unified standard ofbuccal digital film shoot teeth. According to the tooth long axis placed teeth, teethphotos taken at a magnification of1.5times case. Using the national health service based on measurement data processing software Image J image Java language development:A, mesiodistal tooth and tooth long axis perpendicular to the widest part length; B, the cemento enamel junction to the cut end of the long axis parallel with the length of. Two results of four sets of teeth were used for statistical analysis. And the eight sub groups of teeth width, length, average width/length ratio of the analysis of variance. Multiple comparison test (99%confidence interval), to determine whether there are significant differences.Result.Display several sets of data, has certain influence on the degree of abrasion of crown width of teeth. Central incisor group crown width(unworn8.68mm, worn8.87mm), canine group (unworn7.98, worn8.14mm; then the premolars group (unworn7.02,worn7.34mm); and the lateral incisor group (unworn7.03mm,worn7.19mm) is the minimum width. The unworn crown width is significantly less than the worn group.Wear the same degree of crown to crown length has a more obvious effect. Crown the longest is still the unworn central incisor group (11.97mm),followed by the unworn canine group (11.84mm), and worn incisor group (11.48mm).At last the shortest is the worn premolar group (7.81mm). Therefore the crown have obvious impact worn and unworn degree on the length of tooth.Crown width/length ratio in different groups and the results are not the same. The unworn incisor group is0.73, worn is0.77;the unworn lateral incisor group is0.67,the worn group is0.73; the unworn canine group is0.67, worn group is0.75; last premolar unworn group is0.93,worn is0.80.Conclusion:1, The Shandong area of maxillary anterior teeth anatomical crown width to lengthratio respectively (central incisors, lateral incisor, canine, premolar) did not wearrespectively0.72,0.69,0.71,0.73, wear respectively0.77,0.74,0.75,0.83.2, This study for the local population aesthetic crown lengthening operation, filling in treating maxillary anterior teeth, aestheticrestorative treatment, maxillary anterior teeth with the establishment and perfection of provide certain reference to making Chinese ratio measuring scaleand Chinese teeth database.