酪蛋白磷酸肽钙磷复合体对变形链球菌生长、产酸的影响

目的：研究酪蛋白磷酸肽钙磷复合体（Casein phosphopeptide-Amorphic Calcium Phosphate，CPP-ACP）对变形链球菌生长和产酸的影响，探讨CPP-ACP作为一种生物防龋制剂的可行性。方法：将变形链球菌ATCC 25175（血清型c）在含糖的BHI培养基中厌氧培养，在实验组中加入不同浓度（0．5％～5．0％（W／V）的CPP-ACP溶液，厌氧培养48h，采用MTT法检测细菌浓度的吸光度值A（A=550nm），采用精密pH计检测培养御清液的pH值，计算pH的变化值ApH（初始pH值-终末pH值）。结果：随CPP-ACP浓度的升高，变形链球菌的吸光度值降低，即变形链球菌的活菌数减少（P〈0．01）；培养物上清液的pH值升高，ApH降低，即变形链球菌的产酸量降低（P〈0．01）。结论：CPP—ACP具有抑制变形链球菌生长、产酸作用，随浓度升高抑制作用增强。     

当归粗提物抑制变异链球菌的体外实验研究

目的研究当归粗提物对变异链球菌(变链菌)体外生长、粘附及产酸的影响,为当归防龋应用提供参考。方法用醇提法制取当归粗提物,并测量其在不同药物浓度下对变链菌生长、粘附和产酸等作用的抑制效果。结果当归粗提物抑制变异链球菌体外生长的MIC为6.25mg/mL;当粗提物≥1.56mg/mL时,对变链菌的体外粘附和产酸有明显的抑制作用。结论当归粗提物对变链菌的体外生长、粘附和产酸均有一定的抑制作用。     

8种常见儿童牙膏对变形链球菌的抑菌性能比较

据统计,目前我国的人均患龋率为40％,其中儿童患龋率为80％。龋病是牙体硬组织的细菌感染性疾病。变形链球菌（S．mutans）是主要致龋菌之一。它能利用多种糖发酵,最主要的是它利用蔗糖合成葡聚糖,葡聚糖具有粘着性和不溶性附着在牙齿表面,变形链球菌等致龋菌粘附于牙表面的获得性膜上形成菌斑。菌斑中的致龋菌如变形链球菌代谢产生有机酸使牙齿表面脱矿而形成龋齿。     

肇庆市市直机关幼儿园儿童龋齿患病情况分析

目的 :对肇庆市儿童龋齿患病情况分析 ,提出防龋措施。方法 :对 1998～ 2 0 0 3年在托儿童进行口腔检查的结果进行分析。结果 :2岁组儿童患龋率有所下降 ,患龋率随年龄增加而递增 ,6岁组患龋率最高。各年龄组龋均 6年来均呈下降趋势。结论 :儿童龋齿发病率较高 ,严重危害儿童的身体健康。预防龋齿应采取综合措施 ,积极开展防龋方面的卫生宣教 ,老师、家长共同指导督促幼儿口腔卫生行为 ,改变不良饮食卫生习惯 ,幼儿园要配合做好定期检查及氟化泡沫防龋工作     

茶抗龋的动物模型

方法：用变形链球菌Ｉｎｇｂｒｉｔ在Ｗｉｓｔａｒ大鼠上复制出龋齿动物模型，以０．０２１ｍｍｏｌ／Ｌ氟化钠水作为阴性对照，０．０５３ｍｍｏｌ／Ｌ氟化钠水作为阳性对照，给龋模型鼠饲以不同氟浓度（０．０２３ｍｍｏｌ／Ｌ，０．０４２ｍｍｏｌ／Ｌ，０．０５６ｍｍｏｌ／Ｌ）茶水，以Ｋｅｙｅｓ龋齿计分标准和光镜观察作为评价指标，并用扫描电镜，电子能谱观察了茶的抗龋和对釉质龋的再矿化作用。结果：不同浓度的绿茶水均可显著降低龋齿的计分（Ｐ＜０．０１），并对釉质龋有较明显的促进再矿化作用     

幼儿龋和无龋牙菌斑中白色念珠菌临床分离菌株的致龋性

目的探讨幼儿龋(early childhood caries,ECC)和无龋(caries-free,CF)牙菌斑中白色念珠菌临床分离菌株导致幼儿龋的差异性。方法将前期研究中保存的3~6岁幼儿牙菌斑白色念珠菌临床分离菌株,其中来源于幼儿龋牙菌斑为26株(dmft≥1),纳入ECC组;来源于幼儿无龋牙菌斑为24株(dmft=0),纳入CF组。将两组菌株分别接种至不同pH值的葡萄糖沙氏液体培养基中,37℃培养48h后,测定上清液终末pH值以评价产酸能力;分别将两组菌株沉淀用PBS液重悬,采用紫外分光光度仪测定波长540nm处的吸光度(absorbance540,A540)值以评价其耐酸能力。同时将菌液分别接种至羟基磷灰石表面,37℃培养48h后,对黏附至羟基磷灰石表面白色念珠菌进行平板培养,采用菌落形成单位计数法评定其黏附能力。结果当葡萄糖沙氏液体培养基初始pH值≥4.5时,ECC组和CF组白色念珠菌株的产酸和菌株生长能力比较,差异无显著意义(P>0.05);当初始pH值为4.0时,ECC组的产酸和生长能力较CF组强,两组比较,差异有显著意义(P<0.05)。ECC组和CF组白色念珠菌的黏附能力比较,差异无显著意义(P>0.05)。结论幼儿龋和无龋牙菌斑中白色念珠菌临床分离菌株致龋能力的差异,主要体现在耐酸能力方面。强耐酸性白色念珠菌临床分离菌株可能起到促进幼儿龋齿发展的作用。     

响水县儿童龋齿患病情况调查与分析

目的:了解响水县儿童龋齿患病情况,为制订有效干预措施提供依据.方法:对响水县儿童龋齿患病情况、龋齿病因及其相关影响因素进行调查分析.结果:儿童龋患率达48.19%,龋患率与儿童的年龄、婴儿期喂养方式、儿童的饮食和口腔清洁卫生习惯等因素密切相关.结论:应在提倡母乳喂养的基础上,通过培养儿童正确的饮食、口腔卫生习惯等综合性防龋措施,有效地降低龋齿的发生率.     

抗变异链球菌免疫球蛋白对学龄前儿童乳牙龋的预防效果及对口腔链球菌菌群的影响

目的分析抗变异链球菌免疫球蛋白对学龄前儿童乳牙龋的预防效果及对口腔链球菌菌群的影响。方法选取2018年1-12月台州市一幼儿园的180名儿童,分为3组。A组(58名)应用抗变异链球菌免疫球蛋白喷剂防龋,B组(59名)全口涂多乐氟防龋,C组(63名)不给予任何处理。比较3组儿童防龋治疗前后的患龋率、龋均、龋面均。应用PCR法测定防龋治疗前后儿童唾液标本中唾液链球菌、戈登链球菌、血链球菌、口腔链球菌、变异链球菌菌群,观察链球菌菌群数量变化。结果防龋治疗后,3组儿童患龋率比较差异有统计学意义(P0.05)。与防龋治疗前相比,C组儿童防龋治疗后患龋率提高(P0.05)。防龋治疗后,3组儿童龋均和龋面均比较差异均有统计学意义(均P0.05)。与防龋治疗前相比,3组儿童防龋治疗后龋均和龋面均提高(均P0.05)。防龋治疗后,3组儿童口腔链球菌菌群数量比较差异均有统计学意义(均P0.05)。与防龋治疗前相比,A组儿童防龋治疗后唾液链球菌、血链球菌、变异链球菌水平显著降低,口腔链球菌、戈登链球菌水平显著升高(均P0.05),B组和C组儿童防龋治疗后变异链球菌显著升高(均P0.05)。防龋治疗后,A组儿童唾液链球菌、血链球菌、变异链球菌水平显著低于B组和C组(均P0.05),口腔链球菌、戈登链球菌水平均显著高于B组和C组(均P0.05)。结论抗变异链球菌免疫球蛋白和氟防龋均有助于预防学龄前儿童乳牙龋的发生,但抗变异链球菌免疫球蛋白可有效抑制致龋菌,调节口腔链球菌菌群,远期防龋效果更好。同时,抗变异链球菌免疫球蛋白防龋操作简单、方便,易为广大儿童家长所接受,更适宜大范围的普及应用。     

奥丽汀健齿露的研究

1　美国国际ＩｇＹ技术研究开发中心进行的实验1.1　抑制粘附实验 :有明显抑制变链菌粘附的作用。1.2　动物实验 :选用 2 0只大鼠进行变链菌侵染 ,饲料中含高蔗糖。随机分成 2组 :实验组给健齿露饮水 ,对照组给无菌饮水。至第 80ｄ处死大鼠 ,分离牙齿进行检查 ,结果见表 1。表 1　奥丽汀健齿露预防大鼠龋牙形成实验 (牙数 )对照组实验组仅釉质龋损龋损深至牙本质 1 / 4龋损深至整个牙本质472 581 90 .570　　注 :统计学处理两组差异有非常显著性 (Ｐ <0 .0 0 1 )。1.3　临床观察 :选择无龋病、健康自愿者 2 4人 ,实验前全口洁治。分成 2组 ,…     

氟化物防龋和免疫防龋对学龄前儿童龋病的预防效果及对链球菌菌群变化的影响

目的探讨分析氟化物防龋和免疫防龋对学龄前儿童龋病的预防效果及对链球菌菌群变化的影响。方法选取襄阳市1 247名幼儿园儿童,以班级为整体进行随机分组,分为氟化物组417名、免疫组424名、对照组406名,氟化物组儿童每6个月涂多乐氟,免疫组儿童每天使用复合抗龋齿变异链球菌免疫球蛋白(IgY)喷剂,对照组未进行任何处理。3组儿童随访2年,观察儿童患龋情况以及口腔链球菌变化情况。结果氟化物组398名儿童完成随访,失访19名,失访率为4.56%;免疫组386例完成随访,失访38名,失访率为8.96%;对照组399例完成随访,失访7名,失访率为1.72%。3组儿童患龋率、龋均以及龋面均比较,差异均无统计学意义(均P>0.05)。对于无龋儿童,氟化物组预防效果较免疫组更佳,而对于整体儿童而言,免疫组儿童的预防效果较氟化物组儿童更佳。氟化物组与对照组比较,不同干预时间的唾液总链球菌属差异均无统计学意义(均P>0.05);免疫组儿童干预12个月、18个月以及24个月,唾液总链球菌属数量显著低于同期的对照组和氟化物组(P<0.05)。结论氟化物防龋以及免疫防龋均可有效预防学龄前儿童龋病的发生,对于无龋儿童采取氟化物预防的效果更佳,而对于整体儿童而言,采取抗变异链球菌IgY防龋喷剂可有效降低儿童口腔链球菌菌属数量。     

抗变形链球菌IgY对男性青少年防龋的现场试验研究

目的　研究抗变形链球菌IgY对唾液和菌斑中变形链球菌的作用 ,为青少年龋病防治提供依据。方法　将男性正常青少年48人随机分为试验组和对照组 ,分别给予抗变形链球菌IgY和安慰剂 ,每日 2次 ,共 3周。试验前、试验后 1周、试验后 2周、试验后 3周和停药后 1周分别取口腔唾液和菌斑进行细菌培养 ,计算唾液中变形链球菌菌落数以及唾液和菌斑中变形链球菌菌落数占非变形链球菌菌落数的百分率。结果　使用抗变形链球菌IgY 3周后 ,唾液中变形链球菌计数以及唾液和菌斑中变形链球菌菌落数占非变形链球菌菌落数的百分率均下降 ,停药 1周后变形链球菌占总厌氧菌的百分率也明显下降 (P <0 .0 5)。结论　抗变形链球菌IgY对唾液和菌斑中变形链球菌有明显的抑制作用 ,具有防龋作用。     

Immunization against dental caries

Prevention of dental caries has been investigated by immunization with Streptococcus mutans in rodents and subhuman primates. In addition to cells and cell walls of S. mutans, the enzyme glucosyl transferase and purified protein antigens prepared from S. mutans were successfully used in immunization against dental caries. Subcutaneous immunization of rhesus monkeys elicits significant levels of serum IgG, IgM and IgA antibodies, lymphorproliferative response and T cell helper activity to S. mutans cells and to streptococcal antigen (SA) I/II. These immune responses are associated with significant reduction of caries and colonization by S. mutans. However, oral immunization induced only a modest increase in salivary IgA antibodies to S. mutans and a small reduction in caries. Successful immunization in sub-human primates requires optimal T cell helper and minimal suppressor activities in order to elicit high titre and avidity of IgG antibodies. The SA dose required to elicit an optimal T cell helper function in man is HLA-DR dependent. Serum IgG antibodies pass through the gingival crevicular epithelium onto the tooth surface, where they may opsonize S. mutans for phagocytosis by the local neutrophils and prevent adherence of S. mutans, thereby preventing the development of caries.     

Streptococcus mutans, caries and simulation models

Dental caries and dental plaque are among the most common diseases worldwide, and are caused by a mixture of microorganisms and food debris. Specific types of acid-producing bacteria, especially Streptococcus mutans, colonize the dental surface and cause damage to the hard tooth structure in the presence of fermentable carbohydrates e.g., sucrose and fructose. This paper reviews the link between S. mutans and caries, as well as different simulation models that are available for studying caries. These models offer a valuable approach to study cariogenicity of different substrates as well as colonization of S. mutans.     

Mucosal immunization against dental caries with plasmid DNA encoding pac gene of Streptococcus mutans in rats

Salivary secretory immunoglobulin A (S-IgA) antibodies act as the first line of defense against dental caries by blocking of adherence of Streptococcus mutans to tooth surfaces. This study focused on finding proper mucosal immunization route and delivery system to induce higher level of specific anti-S. mutans saliva S-IgA and inhibit dental caries in animal model. By immunizing rats with an anti-caries DNA vaccine, pCIA-P, via different mucosal routes, we found that intranasal (i.n.) immunization with pCIA-P/bupivacaine DNA complexes elicited the highest specific anti-S. mutans saliva S-IgA mucosal antibody responses compared with naked DNA and other routes. Correspondingly, rats immunized with pCIA-P/bupivacaine DNA complex via i.n. displayed the least carious lesions. Our findings suggested that DNA vaccination via intranasal immunization with bupivacaine delivery system be a promising approach against dental caries.     

Asarum sieboldii extracts attenuate growth, acid production, adhesion, and water-insoluble glucan synthesis of Streptococcus mutans

Asarum sieboldii has been used in traditional folk medicine to treat dental caries and periodontal disease. In the present study, we investigated the inhibitory effect of the ethanol and aqueous extracts of A. sieboldii on the growth, acid production, adhesion, and water-insoluble glucan synthesis of Streptococcus mutans. The ethanol and aqueous extracts of A. sieboldii inhibited the growth and acid production of S. mutans. In the bacterial adherence assay, the ethanol and aqueous extracts of A. sieboldii significantly lowered the adherence of S. mutans. We also found that the ethanol and aqueous extracts of A. sieboldii significantly inhibited the synthesis of water-insoluble glucan by crude glucosyltransferase. These results suggest that A. sieboldii extracts may inhibit the caries-inducing properties of S. mutans. Further studies are necessary to clarify the active constituents of A. sieboldii extracts responsible for such biomolecular activities.     

Natural products for dental caries prevention

Selected natural compounds were evaluated for their effects on dental caries due to different strains of Streptococcus mutans bacteria. Out of 39 tested compounds, four (catechol, emetine, quinine, and flavone) showed potent inhibitory activity on different strains of S. mutans at 6.25 microg/mL or less with inhibition of adherence <50%, two compounds (5,7-dihydroxy-4'-methoxy isoflavone and ellagic acid) exhibited a moderate inhibitory effect at 12.5 microg/mL with inhibition to adherence <50%, and 12 compounds exhibited weak antibacterial activity at 125 microg/mL or more with inhibition of adherence <25%. These compounds represent three major classes of natural products: tannins, alkaloids, and flavonoids. Further study for possible application of these compounds as inhibitors for dental caries is underway.     

Immunization against dental caries

Dental caries is one of the most common infectious diseases. Of the oral bacteria, mutans streptococci, such as Streptococcus mutans and S. sobrinus, are considered to be causative agents of dental caries in humans. There have been numerous studies of the immunology of mutans streptococci. To control dental caries, dental caries vaccines have been produced using various cell-surface antigens of these organisms. Progress in recombinant DNA technology and peptide synthesis has been applied to the development of recombinant and synthetic peptide vaccines to control dental caries. Significant protective effects against dental caries have been shown in experimental animals, such as mice, rats and monkeys, which have been subcutaneously, orally, or intranasally immunized with these antigens. Only a few studies, however, have examined the efficacy of dental caries vaccines in humans. Recently, local passive immunization using murine monoclonal antibodies, transgenic plant antibodies, egg-yolk antibodies, and bovine milk antibodies to antigens of mutans streptococci have been used to control the colonization of the organisms and the induction of dental caries in human. Such immunization procedures may be a safer approach for controlling human dental caries than active immunization.     

学龄前儿童IgY免疫防龋疗效观察

目的探讨IgY对乳牙的被动免疫防龋作用,为防治学龄前期儿童乳龋提供依据。方法将杭州采荷大地学前教育集团幼儿园3岁儿童280名,随机分成实验组和对照组各140人;实验组使用含防龋抗体IgY的口腔喷剂,对照组使用不含防龋抗体IgY的口腔喷剂。分别在使用前和使用后1 a,1.5 a,2 a检查乳牙患龋状况。结果实验前和实验后1 a,1.5 a,2 a的患龋率实验组分别为57.1%,62.9%,64.3%和66.4%,对照组分别为56.4%,73.0%,77.9%和81.4%;龋均实验组分别为2.0,3.1,3.3和3.5,对照组分别为2.6,3.7,4.0和4.5;龋面均实验组分别为3.8,6.6,6.8和6.9,对照组分别为4.8,8.0,8.3和8.8。实验组患龋率、龋均和龋面均显著低于对照组(P值均<0.01)。结论 IgY能有效抑制儿童乳牙龋的发生,对龋病有预防作用。     

张家港市2299名学龄前儿童龋病调查分析

目的 了解张家港市学龄前儿童龋病的流行情况及易感因素.方法 抽取张家港市23所幼儿园的2 299名学龄前儿童对其进行口腔检查并发放问卷,由家长填写后统一收回.应用x2检验筛选出乳牙龋病易感者的相关因素.结果 学龄前儿童患龋率为61.11％,龋均为3.42,龋失充填率为2.79％;男童、女童患龋率差异无统计学意义（P＞0.05）;随着年龄的增长,患龋率升高,不同年龄组间患龋率差异有统计学意义（P＜0.05）;不同牙位乳牙患龋率差异有统计学意义（P＜0.05）,上颌乳中切牙患龋率最高,其次为下颌的乳磨牙;儿童口腔卫生、饮食习惯,父母口腔卫生知识、态度和行为等多因素与儿童乳牙龋病密切相关.结论 张家港市学龄前儿童的患龋率较高,需早期开展预防工作;加强对父母口腔知识的宣传、刷牙指导,限制糖的摄入频率以及避免不当的进食方式对预防乳牙龋极为重要.