Tedjosasongko Udijanto, Kozai Katsuyuki
Department of Pediatric Dentistry, Graduate School of Biomedical Sciences, Hiroshima University.
ASDC J Dent Child. 2002 Sep-Dec;69(3):284-8, 234-5.
The purposes of this study were to determine the age at the initial acquisition of mutans streptococci (MS) and to determine the transmission of MS among children at day nursery by describing the occurrence of genotypes prepared by chromosomal DNA fingerprinting of the bacteria using restriction endonuclease EcoRI and HaeIII. The samples were 39 children (23 boys and 16 girls) aged 0-5 years old, 14 pairs of parents and 6 nursery caretakers of a day nursery in Hiroshima city, Japan. The children had no dental caries throughout the experiment. Plaque samples of the children were taken using toothbrushes at 1 month intervals for 30 months. The initial acquisition of MS occurred between the ages of 8 months and 52 months with a mean age of 24.2 months. The cumulative probability of initial acquisition of MS increased rapidly at the age of 12 to 25 months after 10 to 20 primary teeth had erupted. Transmission of MS was found between child and mother (33.3%), child and father (8.3%) and child and others including amongst the children (58.4%), but no evidence of MS transmission from nursery caretakers was found. Two children acquired MS from intra- and extra-familial transmission. This study suggests that the child's environment also plays a role in the initial acquisition and transmission of MS, in addition to the oral condition of the children.
本研究的目的是通过描述使用限制性内切酶EcoRI和HaeIII对细菌进行染色体DNA指纹分析所制备的基因型的出现情况，来确定变形链球菌（MS）初次获得的年龄，并确定日托中心儿童之间MS的传播情况。样本来自日本广岛市一家日托中心的39名0至5岁儿童（23名男孩和16名女孩）、14对父母以及6名托儿所保育员。在整个实验过程中，这些儿童均无龋齿。每隔1个月用牙刷采集儿童的菌斑样本，共采集30个月。MS的初次获得发生在8个月至52个月之间，平均年龄为24.2个月。在10至20颗乳牙萌出后的12至25个月龄时，MS初次获得的累积概率迅速增加。发现MS在儿童与母亲之间（33.3%）、儿童与父亲之间（8.3%）以及儿童与包括其他儿童在内的其他人之间（58.4%）存在传播，但未发现有MS从托儿所保育员传播的证据。两名儿童通过家庭内和家庭外传播获得了MS。这项研究表明，除了儿童的口腔状况外，儿童的环境在MS的初次获得和传播中也起作用。
