蔗糖浓度对重症婴幼儿龋菌斑中变型链球菌致龋性的影响  

Effect of Sucrose Concentration on Cariogenicity of Streptococcus mutans in Dental Plaque of S-ECC

作　　者：赵玮[1] 李文卿[1] 卢佳璇[1] 余东升[2] 

机构地区：[1]中山大学光华口腔医学院儿童口腔科,广东广州510055 [2]中山大学光华口腔医学院口腔颌面外科,广东广州510055

出　　处：《中山大学学报（医学科学版）》2011年第5期623-627,共5页Journal of Sun Yat-Sen University:Medical Sciences

基　　金：国家自然科学基金(30973340);广东省自然科学基金项目(9151008901000187);广东省科技计划社会发展项目(00316971120302088)

摘　　要：【目的】探讨不同蔗糖浓度对重症婴幼儿龋(S-ECC)菌斑中变形链球菌致龋性的影响。【方法】采集67名3～5岁S-ECC及无龋儿童牙面菌斑,获取纯化的变链菌株,接种至蔗糖浓度分别为1%、5%、10%及20%的PYG液体培养基,采用精密pH计测变链菌产酸能力;分光光度仪测定OD600值,评价其生长情况;蒽酮法测定水不溶性葡聚糖(WIG)的量;比浊法测定变链菌的黏附比值,对比分析变形链球菌不同临床菌株的致龋性。【结果】随蔗糖浓度升高,S-ECC及无龋组变形链球菌临床分离菌株产酸、合成胞外多糖及粘附能力均呈增长趋势,并且表现为蔗糖浓度依赖性。S-ECC组变链菌株△pH值、OD600值、合成WIG量及黏附比例均显著高于无龋组。S-ECC组中,变链菌株的产酸能力随蔗糖浓度增高而增强,当蔗糖浓度达5%时,变链菌株产酸降至釉质脱矿临界pH 5.5附近;变链菌株生长情况(OD600值)显示,当蔗糖浓度大于5%时,变链菌生长情况良好,S-ECC组表现得最为明显,当蔗糖浓度大于10%,变链菌株生长速率有所降低,无龋组10%浓度蔗糖作用下OD600值甚至高于20%浓度组;变链菌株合成WIG的量随蔗糖浓度增高而增加,当蔗糖浓度大于10%,WIG合成增长变缓;随着蔗糖浓度增高,变链菌黏附比值增加,蔗糖浓度大于5%时,增长趋势变缓慢。【结论】S-ECC菌斑中变型链球菌致龋性与蔗糖浓度有关,随蔗糖浓度升高变链菌株的致龋能力增强,5%及以上浓度蔗糖具有较强的致龋性,应予以足够重视。【Objective】 To determine the effect of sucrose concentration on cariogenicity of Streptococcus mutans in dental plaque of S-ECC.【Methods】 Plaque samples were collected from 67 children aged from 3 to 5.Strains of Streptococcus mutans were identified,purified and then cultured in PYG medium with 1%,5%,10%,and 20% sucrose.The pH value of supernatant was measured to evaluate acidogencity of Streptococcus mutans,and OD600 to evaluate the propagating status.The quantities of water insoluble glucans（WIG） were measured by anthrone method.Turbidimetry was used to measure the adhesive ability.【Results】 Acidogenicity,propagation,WIG synthesis,and adhesion ratio of Streptococcus mutans from S-ECC group were statistically higher than caries free group.The cariogenicity of Streptococcus mutans enhanced with the increase of sucrose concentration.In 5% sucrose group,pH decreased to critical pH5.5.Propagation,WIG synthesis and adhesion ratio increased a lot,especially in S-ECC group.When sucrose concentration was above 5%,pH,OD600,WIG and adhesion ratio still increased,however,the growth rate became slow down.【Conclusion】 The cariogenicity of Streptococcus mutans was dose-dependent with sucrose levels,and the concentration of which exceeded 5% is considered to be more cariogenic and important for S-ECC prevention.

关 键 词：儿童早期龋 变形链球菌 蔗糖 

分 类 号：R569[医药卫生—呼吸系统]