The Longitudinal Study Of Maxillary Teeth In Northern Fujian Province

Objective:The purpose of study was to analyze the patterns of tooth movement about thefront teeth from the primary dentition period, the mixed dentition period to thepermanent dentition period. Analyzing the patterns of canine width could provide areferent evidence for diagnose of early malocclusion of children and early treatmentin Zhenghe country, in Fujian province.Method:For the fist study, the sample is consisted of34subjects (19males and15females)from Zhenghe country, Fujian province. The casts was maded every two years,5casts altogether each subject. All tooth cast were scanned and changed into digitaltooth cast by3DSS technology and Geomagic Studio12.0software. Then five seriesof the dental casts were superimposed at the triangle that maded from the middle ofthe incisive papilla and the first palatine fold by3Matic software. And then thelandmark of maxillary incisor, lateral incisor and canine were selected by curveanalysis of3Matic software and measure these landmarks development track in the lippalate. Lip is positive, while jaw is negative. At last, SPSS19.0statistical softwarewas adapted to analysis the data. The trajectory of front teeth and the peak period ofdevelopment were achieved.For the second study, the landmark of maxillary canine was selected by the curveanalysis of3Matic software. Then the width was measured between the landmarks. Atlast SPSS19.0statistical software was adapted to analysis the data.Result:1. From early mixed dentition、mixed dentition to early permanent dentition, theregular pattern of the front teeth as follows: the whole moving trajectory of maxillarycentral incisor is not respectively, left and right also has no significant difference.2. The lateral incisor aged5.5to7.5on the right side has no statistical significancebetween men and female, while the left side (P≤0.05）was statistically significant and the average growth of man is greater than woman; but the moving trajectory from theage of5.5to11.5（P＞0.05) was no significant difference. the whole movingtrajectory of maxillary canine teeth is（P＞0.05) has no statistical significance, leftand right also has no significant difference.3. Since5.5to9.5years old, the intercanine width has no obvious differencebetween male and female（P＞0.05); from11.5to13.5years,there are differencebetween the male and female(P≤0.05）, and the width of male is larger than female.4. From5.5to13.5years old, the average intercanine width in different ages asfollows:AgeWidth(x±s,mm）（y） F M5.530.189±1.3857.532.379±1.4239.534.377±1.55311.536.142±1.19535.112±1.23813.536.912±0.98035.847±1.1385. From5.5to13.5years old, the overall growth of intercanine width is: M6.723mm F5.658mm, the trend is a slow growth.Conclusion:1. From early mixed dentition、mixed dentition to early permanent dentition, thewhole moving trajectory of maxillary front teeth have no statistical significancebetween man and female, left and right also has no significant difference. The growthpeak of the maxillary central incisor and lateral incisor appeared in the age of7.5to9.5; while the maxillary canine teeth appeared in the age of9.5to11.5; and themoving trajectory is the most obvious in the maxillary central incisor.2. Since5.5to9.5years old, the intercanine width has no obvious differencebetween male and female, from11.5to13.5years,there are difference between themale and female, and the width of male is larger than female; From5.5to13.5yearsold, the overall growth of intercanine width is: M6.723mm F5.658mm, the trend is a slow grow.