托槽对上切牙菌斑中变形链球菌影响的定量研究

Effects of Brackets on Mutans Streptococcus in Plaque Between Maxillary Incisors:A Quantity Study

目的对粘结托槽前后菌斑中变形链球菌数量的差异进行定量研究。方法采用自身对照法。每个患者分两阶段取样:粘结托槽前和粘结托槽后4周;取样牙位包括上4个切牙。设计针对变链菌的特异性引物和MGB探针,应用实时荧光定量PCR技术测定每毫克菌斑样本中变链菌的数量。结果同一患者粘托槽前后变链菌数值分别为5.31×106/mg和6.35×106/mg,其差别有统计学意义(P=0.0025)。结论患者粘结托槽后,菌斑中变链菌密度的明显升高,可能是正畸治疗中白垩斑发生率较高的原因之一。

[Objectives] To compare the amount of mutans streptococcus in plaque before and after the fixed appliance bonding. [Methods] The present study was designed as a randomized paired study. Plaque samples were taken from the surface around the bracket of four maxiUary incisors before and after the fixed appliances bonding for four weeks. The amount of MS per mg of plaque was measured by real time fluorescence-quantitative PCR. [Results] The counts of mutans streptococcus in plaque before and after the fixed appliance bonding were 5.31×10^6 /mg and 6.35×10^6/mg respectively, and the increase has statistical significance （P=0.0025）. [Conclusions] The significant increase of the density of mutans streptococcus during orthodontic treatment maybe the etiology agent for enamel demineralization.