Sabel Nina, Klinberg Gunilla, Nietzsche Sandor, Robertson Agneta, Odelius Hans, Norén Jörgen G
Department of Pedodontics, Institute of Odontology at the Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden.
Swed Dent J. 2009;33(2):85-95.
The primary teeth start to mineralize in utero and continue development and maturation during the first year of life.The aim of this study was to investigate the concentrations of some elements, C, F, Na, Mg, Cl, K and Sr, by secondary ion mass spectrometry (SIMS) in human primary incisors at different stages of mineralization.The teeth derived from an autopsy material from children who had died in sudden infant death.The buccal enamel of specimens from the ages 1, 2, 3, 4, 6 and 19 months, respectively, was analyzed. It was evident that posteruptive effects play an important role in composition of the outermost parts of the enamel. Before the tooth erupts, the concentrations of the elements vary with the maturation grade of the mineralization in the enamel. Sodium was the element with the highest concentration of the measured elements and chlorine was the element of lowest concentration.The 19 month old specimen, considered as the only mature and erupted tooth, showed to differ from the other specimens.The concentration of fluorine, in the 19 month old specimen's outermost surface, is readily seen higher compared with the other specimens at this depth zone. In the 19 month old specimen the concentration of carbon is lower. Potassium, sodium and chlorine have higher concentrations, in general, in the 19 month old specimen compared with the immature specimens. The thickness of the enamel during mineralization was calculated from data from SIMS.The thickness of the buccal enamel of primary incisors seemed to be fully developed between 3-4 months after birth, reaching a thickness of 350-400 microm.
乳牙在子宫内开始矿化，并在出生后的第一年继续发育和成熟。本研究的目的是通过二次离子质谱法（SIMS）研究人类乳牙在不同矿化阶段中一些元素（碳、氟、钠、镁、氯、钾和锶）的浓度。这些牙齿来自于因婴儿猝死而死亡儿童的尸检材料。分别对年龄为1、2、3、4、6和19个月的标本的颊侧釉质进行了分析。很明显，萌出后效应在釉质最外层的组成中起重要作用。在牙齿萌出之前，元素的浓度随釉质矿化成熟度而变化。钠是所测元素中浓度最高的元素，氯是浓度最低的元素。19个月大的标本被认为是唯一成熟且已萌出的牙齿，与其他标本不同。在这个深度区域，19个月大标本的最外层表面的氟浓度明显高于其他标本。在19个月大的标本中，碳的浓度较低。总体而言，与未成熟标本相比，19个月大标本中的钾、钠和氯浓度更高。根据SIMS数据计算了矿化过程中釉质的厚度。乳牙颊侧釉质的厚度在出生后3 - 4个月似乎已完全发育，达到350 - 400微米的厚度。
