微型pH电极直接测试人牙菌斑pH的应用研究

目的：进一步探讨微型ｐＨ电极在原位检测人牙菌斑ｐＨ的可行性，了解漱糖后对菌斑ｐＨ的影响。方法：采用微型蜂式ｐＨ指示电极直接测试人牙邻面菌斑ｐＨ变化。结果：微型ｐＨ电极与玻璃ｐＨ大电极所测结果基本一致；漱糖后菌斑ｐＨ呈下降趋势，２０ｍｉｎ时达到最低点；无龋组与龋敏感组之间的ｐＨ改变无显著性差异。结论：微型ｐＨ电极适用于在原位直接测试菌斑ｐＨ；漱糖后菌斑ｐＨ发生改变，但龋坏与否的个体之间未见明显不同     

用于牙菌斑pH测定的复合型微pH电极的研制

目的　研制可用于测定菌斑pH值的微pH电极。方法　用循环伏安法聚苯胺修饰钨丝电极作为pH指示电极 ,用Ag AgCl丝作为参比电极 ,二者复合于塑料套管内构成复合型pH微电极 ,试用于菌斑pH的测定。结果　在pH3～ 12范围内 ,该电极呈现Nernst响应 ,响应时间 <2min。将该电极试用于菌斑pH测定 ,获得蔗糖含漱后菌斑pH变动曲线。结论　该电极可用于菌斑内pH测定 ,且有望用于体内其它微小环境pH测定。     

牙菌斑pH检测电极技术的研究进展

牙菌斑pH检测技术可检测龋风险,辅助预防龋病,其理论成熟、操作相对简单。由于临床龋风险检测技术的需求提高,微电极技术迅速发展,目前可实现牙菌斑pH检测的微电极种类也逐渐增加。现有电极技术主要包括微型玻璃电极、金属氧化物微电极以及离子敏感场效应晶体管。微型玻璃电极首先被应用于牙菌斑pH值的检测,但其结构薄弱,其中氧化铱微电极以其高强度、响应性优良的特点,成为近年来最具有应用潜力的接触法龋风险检测电极。金属氧化物微电极可以有效弥补玻璃电极强度不足的问题。随着电极技术进一步发展,更加小型、灵敏的离子敏感场效应晶体管受到研究者的关注。另外,为了克服接触法破坏菌斑结构的问题,近年来也有学者提出了光学测定技术,该技术可以实现无接触牙菌斑pH检测。未来的研究将在保证微小化的前提下进一步提高电极的强度及性能,并向无接触检测方向发展。     

牙菌斑pH值的检测及其影响因素

牙菌斑中一些细菌可以分解碳水化合物产酸 ,导致牙齿硬组织脱矿 ,ｐＨ值的变化正是反映了菌斑细菌的产酸情况。本文就菌斑ｐＨ的检测及影响检测结果的因素综述如下。一、牙菌斑糖分解代谢的基本情况菌斑细菌可以将菌斑基质中的纤维素、淀粉、寡聚糖、透明质酸等分子较大的碳水化合物分解为单糖或二糖。这些降解产物以及外源性的蔗糖、乳糖、葡萄糖、麦芽糖可通过透性酶转运系统、磷酸转运酶系统 (ＰＴＳ)进入变形链球菌等致龋菌细胞 ,经糖酵解 (ＥＭＰ)、磷酸己糖旁路 (ＨＭＳ)、恩特纳-道德洛夫 (ＥＤＰ)等途径分解 ,产生大量有机酸 ,使菌…     

牙菌斑pH值的动态变化及检测技术的研究进展

龋病是发生在牙齿硬组织的慢性感染性疾病,其发生、发展与菌斑pH值密切相关.牙菌斑pH值为衡量菌斑生物膜致龋力的重要指标,通过菌斑pH值的动态变化及菌斑pH值检测技术的研究,可以了解菌斑的产酸代谢情况,比较食物、菌斑的潜在致龋力、个体的龋易感性等,对龋病的防治有重要意义.本文重点综述菌斑pH值的动态变化,以及菌斑检测技术...     

牙菌斑氮源物质代谢与pH值变化

<正>牙菌斑中物质代谢活动是在牙菌斑微生态系中进行的,与代谢有关的底物、代谢条件以及代谢产物都将影响牙菌斑微生态环境。氮源物质代谢是牙菌斑中物质代谢的重要部分,可为细菌的生长提供必需的氨基酸,同时氨基酸可作为能源.代谢产生碱性物质对牙菌斑pH进行调节,从而对牙菌斑生态环境的平衡和稳定发挥重要作用。     

咀嚼木糖醇口香糖后牙菌斑pH值的变化趋势

目的:接触法测定咀嚼木糖醇口香糖后牙菌斑原位pH值的变化趋势。方法:在9名志愿者停止口腔卫生措施48h后,采用pH微电极测定其菌斑原位pH值作为基线,再含漱0.1kg/L蔗糖溶液后测定即刻、3、8、13、20、30、40min时的菌斑pH值,然后分别咀嚼蔗糖口香糖和木糖醇口香糖,测定以上相同时间点、相同位点的菌斑pH值。结果:受试者含漱0.1kg/L蔗糖溶液和咀嚼蔗糖口香糖后,3~13min时降到最低值,此后菌斑pH值缓慢回升,至30~40min时与基线水平无显著性差异。而咀嚼木糖醇口香糖后,菌斑pH值呈上升趋势,3min时达最高,13min后pH值逐渐接近基线水平(与基线水平无显著性差异)。木糖醇口香糖组与蔗糖口香糖组、0.1kg/L蔗糖溶液组相比,pH值下降幅度在不同时间点均有显著性差异。结论:咀嚼木糖醇口香糖可以升高牙菌斑pH值,有促进釉质再矿化的功效。     

Effect of buccal administration of a lactose-containing nitroglycerin tablet (Suscard) on plaque pH

The aim of this study was to monitor pH in 2-day-old dental plaque after administration of a long-acting, lactose-containing nitroglycerin tablet (Suscard). The tablet was placed under the lip of the maxilla. This was done both in two older subjects suffering from heart problems and in 10 younger, healthy subjects. In the latter group, a sucrose-containing lozenge was used as a control. The influence of a 5-wk period of daily use of Suscard (in the two elderly subjects) and the effect of normal oral hygiene procedures (in the 10 younger subjects) on the pH response was also studied. Plaque pH was measured in situ up to 1 h, at five different approximal sites in the front region of the maxilla by the microtouch method. The Suscard tablet resulted in a fall in plaque pH in both groups when teeth had not been brushed for 2 days. The lowest pH was recorded at the sites close to where the tablet had been placed. The most attenuated pH drop was found in the two older subjects, who showed a mean minimum pH of 5.7, as compared with 6.2 for the younger subjects. No further increase in the pH fall from Suscard was seen after the 5-wk period in the two patients with heart problems. In the 10 younger healthy subjects, the most pronounced pH decrease was registered after administration of the sucrose-containing lozenge. The pH drop for Suscard was not significant when normal oral hygiene procedures preceded the test. To conclude, this study showed that a long-acting, lactose-containing nitroglycerin tablet may be highly cariogenic. However, if good oral hygiene is maintained, the pH drop in plaque can be reduced to a minimum.     

木糖醇加锌漱口液对牙菌斑pH值影响的实验研究

目的:对比含锌漱口液、木糖醇加锌漱口液以后对含漱蔗糖溶液后菌斑pH值变化的影响,从菌斑代谢角度探讨木糖醇的抗龋机制。方法:采用微型pH电极接触法,原位测定含锌和含木糖醇加锌漱口液 30、60、120min后,含漱蔗糖溶液 1h内的菌斑pH值变化。结果:使用含锌漱口液 60min后,仍可以抑制细菌糖代谢产酸;而用含锌和木糖醇的溶液可以持续发挥抑制作用达 120min。结论:含锌的木糖醇溶液具有抑制牙菌斑细菌糖代谢产酸的能力,在相同的锌离子浓度下,含锌和木糖醇溶液比单纯含锌溶液的抑制细菌代谢产酸力强,并且作用的时间也明显延长,这可能是两者共同作用的结果。     

不同饮料对不同龋敏感儿童牙菌斑pH值的影响

目的 比较不同种类的饮料对龋敏感儿童及无龋儿童牙菌斑pH值的影响。方法 采用微型蜂式pH指示电极原位测试儿童牙菌斑pH值。选择四川省成都市幼儿园3～5岁无龋儿童10名和龋敏感儿童10名作为研究对象,观察其饮用可口可乐、统一鲜橙多及乐百氏AD钙奶饮料后牙菌斑pH值的动态变化。结果 无龋和龋敏感组儿童牙菌斑的静止pH值有统计学差异（P<0.05）。饮用饮料后,各组牙菌斑pH值均下降,约5～10 min后达到最低值。无龋组儿童饮用3种饮料后pH最小值（pHmin）和pH下降幅度（△pH）均无统计学差异（P>0.05）;龋敏感组儿童饮用3种饮料后pHmin、△pH则有统计学差异（P<0.05）。结论 龋敏感儿童的牙菌斑产酸力较无龋儿童高。不同饮料对牙菌斑pH值的改变不同,其潜在的致龋能力存在差异。     

Computerized planimetric method for clinical plaque measurement

A computerized planimetric method for plaque area measurement has been developed. Using a computerized image analysis system (CIAS), the plaque area and tooth area on color slides were digitized and the number of pixels automatically counted. The proposed Plaque Percent Index (P% Index) expresses plaque area as a percentage of tooth area. The reproducibility of this method was tested and the influence of photographic technique on the P% Index was determined. The association of the Turesky modified Quigley-Hein plaque index (Q-H Index) and the P% Index was assessed. The present method was highly reproducible for the P% Index with an intraexaminer variation of 0.28% and intraexaminer correlation coefficient of 0.99. The results show that highly reproducible P% Index values with an error of less than 3.0% were obtained when the photographs were taken under the following conditions. For the buccal surfaces of anterior teeth, the slides were photographed within a 20-degree range in the horizontal plane and a 30-degree range in the vertical plane; and for the lingual/palatal surfaces of anterior teeth and the buccal or lingual/palatal surfaces of posterior teeth, the slides were photographed with an image of the whole tooth surfaces in the photographic mirrors. The comparison of the Q-H Index and the P% Index revealed that for each score of the Q-H Index the corresponding values of P% Index were wide with a significant crossover value, although a strongly positive correlation was found between the Q-H Index and the P% Index (r = 0.92, P <0.01). This study indicates that the proposed P% Index, quantitatively expressed on an interval scale, has high reproducibility and discriminative power.     

Some aspects of the dynamics of Cu and Zn retained in plaque as related to their effect on plaque pH

Abstract – The effect of glucose on acid production in dental plaque was measured in vivo after oral rinses with CuSO₄ (1.0 mM) or Zn (Ac)₂ (20 mM) and compared with the retention of the metals. Plaque samples were analyzed for copper and zinc by neutron activation analysis. A rinse with the copper salt solution significantly depressed acid formation in plaque for a period of 6 h whereas a rinse with the zinc solution was effective for 2 h. Plaque concentrations of the metals increased from less than 75 p.p.m. to more than 1000 p.p.m. 2 h after a rinse with the metal salts. Twelve hours after a rinse the mean plaque concentrations were 190 p.p.m. Cu or 358 p.p.m. Zn respectively. Reducing the pH of the copper sulfate solution from 5.7 to 2.0 yielded lower Cu concentrations in plaque 2 h after a rinse, indicating lower initial retention. The results clearly demonstrate a high and long lasting retention of metal ions in dental plaque and their biological effect in this environment.     

Assessment of denture plaque pH in subjects with and without denture stomatitis

abstract — To evaluate the "resting" pH and induced pH changes in denture plaque, soft deposits were collected from the fitting surface of the denture, pooled and suspended in water. Plaque pH was determined with microelectrode equipment before and after mouth rinsing with a sucrose solution. A characteristic level in the "resting" pH of denture plaque was found in most of 12 subjects tested. pH values below the baseline level were recorded for more than 2 h after a rinse. The pH depressions were more pronounced in maxillary than in mandibular plaque. Further, the pH minima tended to be lower in subjects with denture stomatitis than in. controls. No clear relationship could be established between the "resting" pH and the concentration of Candida hyphae in denture smears or palatal inflammation.     

咀嚼木糖醇口香糖对牙面菌斑原位pH值的影响

目的通过对牙面菌斑原位pH值的动态检测，观察咀嚼木糖醇口香糖对牙菌斑pH值的影响。方法采用受试者自身对照的试验方法，选择9名健康成人志愿者为受试对象，用pH微电极在口内测定菌斑的原位pH值。在测定受试者牙面48小时成熟菌斑的基线pH值之后用10％的蔗糖溶液漱口，测定漱口后即刻、3、8、13、20、30、40分钟后菌斑的pH值，然后分别咀嚼蔗糖口香糖和木糖醇口香糖，测量相同时间点、相同位点牙菌斑的pH值。结果用10％的蔗糖溶液漱口后牙菌斑pH值迅速下降至5．5以下，咀嚼蔗糖口香糖后牙菌斑pH值也有下降。但下降幅度较小，在即刻、3、8分钟三个时点二者之间有显著性差异（P〈0．05）。咀嚼木糖醇口香糖后牙菌斑的pH值没有下降，在即刻、3、8、13、20分钟五个时点的pH值明显高于咀嚼蔗糖口香糖后的pH值（P〈0．05）。结论咀嚼木糖醇香糖不会导致口腔中牙菌斑pH值的下降，有助于釉质再矿化。