- 期刊
臺灣兒童第一顆萌發之恆牙－二第－大臼齒或是門牙？
Eruption Sequence of the First Permanent Molar and Mandibular Incisor in Taiwanese Children
摘要
研究目的：本研究之目的在探討臺灣兒童恆牙萌發之情形，以及第一顆萌發之恆牙究竟是第一大臼齒或是下顎門牙。 方法：本研究檢查年齡四至七歲之兒童1000名，從中篩選出第一顆恆牙正在萌發者271名。看到有任何部份之白色牙冠穿出牙齦者，則定義為已萌發之牙齒。若是第一大臼齒及下顎門牙都已萌發，則不納入本研究中。將萌發之資料加以統計，並以X^2-test測試男女之間是否有差異性存在。 結果：在這271位第一顆恆牙正在萌發之兒童中，男性147位、女性124位。第一顆萌發之恆牙為下顎門牙者有132位，占48.7％。而第一顆萌發之恆牙為第一大臼齒者有139位，占51.3％。下顎門牙先萌發之男孩有75位，占所有男童之51.0%；但女孩下顎門牙先萌發者有57位，占所有女童之46％。X^2-test顯示男孩下顎門牙先萌發者較多，且與女孩之間有顯著差異性存在。第一顆恆牙萌發之平均年齡為6歲又1.6個月，男生第一顆恆牙萌發之時間比女生晚1.6個月。 結論：本研究顯示，恆牙第一大臼齒及下顎門牙有相同的機會成為第一顆萌發出來之恆牙。故我們在回答家長時，應該更正為：第一大臼齒及下顎門牙都有可能是第一顆萌發出來之恆牙，兩者各占一半之機會。但男生有較多之機會下顎門牙先長；而女生則有較多之機會第一大臼齒先長。
並列摘要
Purpose: The purpose of this study was to investigate the eruption sequence of the first permanent molar and mandibular incisor in Taiwanese children. Materials & Methods: After screening of 1000 children aged between 4-7 years, data on tooth eruption were collected from 271 children who lived in central Taiwan. Tooth emergence was recorded by direct inspection and considered to have emerged if any part of the crown was visible. Those children who had their incisors and molars present simultaneously were not included in this study. X^2 -test was used in this study to compare the gender difference. Results: The results showed that in these 271 children (124 girls and 147 boys), 132 (48.7%) children whose mandibular incisors erupted earlier than the first permanent molars; and 139 (51.3%) children whose permanent molars erupted earlier than the mandibular incisors. The mandibular incisors erupted earlier than the first mandibular molars in 51.0% of the boys, but only in 46% of the girls whose incisors erupted earlier than the molars; and there was statistically significant between boys and girls. The average age of the first permanent tooth eruption was 6 years and 1.6 months. The average age of first permanent tooth eruption in boys was 2 months later than that of in girls. Conclusions: This study concludes that the first erupted permanent tooth in Taiwanese children is either mandibular incisor or mandibular molar. The chance that an incisor or molar erupts first is about the same. It is more likely in boys that the mandibular incisors will erupt first.