For the evaluation of the eruption time of the deciduous teeth, in Korean, the infants consist of 1223 male and 831 female whose deciduous teeth are emerging were selected through oral examination.
Only the cases which have any portion of cutting edge or occlusal cusp just pierced gingival mucosa were included in the subject of this study, and were calculated statistically. Following results were obtained.
1. Average ages (month, day) for eruption of the deciduous teeth were as follws.
(MS.D)
Upper deciduous central incisor ´´´ """"""""´8,251,14
Lower deciduous central incisor ´ """"´""""""7, 251,15
Upper deciduous lateral incisor ""´ 10,21-2,03
Lower deciduous lateral incisor 11,152, 05
Upper deciduous canine ---***--´*15,273,22
Lower deciduous canine 16, 093,19
Upper deciduous first molar 17,033,22
Lower deciduous first molar 17,10-3, 21
Upper deciduous second molar "23,274,28
Lower deciduous second molar ´""´"´ *---´**´**´--23, 024,19
2. The eruption sequence of the deciduous teeth was as follows.
lst Lower deciduous central incisor
2nd Upper deciduous central incisor
3rd Upper deciduous lateral incisor
4th Lower deciduous lateral incisor
5th Upper deciduous canine
6th Lower deciduous canine
7th Upper and lower deciduous first molars
8th Lower deciduous second malar
9th Upper deciduous second molar
3. In the view of sex difference, the eruption of the deciduous central and lateral incisors seened to be earlier in the male than in the female, and of the other dccfducus teeth seemed to be earlier in the female.
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