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。     

咀嚼麦芽糖醇口香糖对牙菌斑原位pH值的影响

目的探讨咀嚼麦芽糖醇口香糖后牙菌斑原位pH值的变化趋势。方法将30名13～15岁龋易感儿童随机分为3组，即麦芽糖醇口香糖组（A组）、木糖醇口香糖组（B组）、胶母口香糖组（C组）。通过微电极原位接触法对牙菌斑pH值进行检测，观察咀嚼口香糖4W前后菌斑pH值的变化趋势。结果三组受试者分别在咀嚼口香糖后，菌斑pH值于各个时间点均呈上升趋势，约20min达到最高值，随后仍保持高于基线值水平。咀嚼口香糖4周后，三组各时间点牙菌斑pH值均上升，与咀嚼前比较具有显著性差异（P〈0．05）；三组间在各个时间点pH值上升幅度（△pH）比较具有显著性差异（P〈0．05）。结论麦芽糖醇口香糖对牙菌斑pH值的作用同木糖醇口香糖一样较为明显。     

咀嚼无糖口香糖对含漱蔗糖溶液后牙菌斑原位pH值的影响

目的 通过对牙菌斑原位pH值变化的动态监测，观察咀嚼无糖口香糖对牙菌斑原位pH值的影响。方法 采用受试者自身对照的临床试验方法，选择16名健康成人志愿者为受试者，年龄23～32岁，其中男性6名，女性10名。首先测定受试者48h菌斑的静止pH值，以及受试者用10％蔗糖溶液含漱1min后在5、10、20和30min时菌斑的pH值，取得受试者的Stephan曲线作为基线对照；而后观察咀嚼两种益达无糖口香糖对含漱10％蔗糖溶液后菌斑pH值变化的影响。菌斑原位pH值的测定采用pH微电极接触法在口内直接测量。结果 含漱10％蔗糖溶液后立即开始咀嚼无糖口香糖可使菌斑pH值在各检测时间点(含漱10％蔗糖溶液后5、10、20和30min)均维持在静止pH水平，无明显下降；含漱10％蔗糖溶液后在5min时开始咀嚼无糖口香糖则使菌斑pH值从含漱蔗糖溶液后5min时的5．59迅速回升至10min时的6．98。结论 受到蔗糖攻击后，咀嚼无糖口香糖可迅速缓冲菌斑的酸性产物，升高菌斑pH值。     

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。     

咀嚼口香糖对含漱蔗糖溶液后牙菌斑原位pH值的影响

目的：观察咀嚼含糖口香糖和含木糖醇口香糖对牙菌斑原位pH值变化的影响。方法：选择10名健康青年志愿者，采用受试者自身对照的临床试验方法，分别检测受试者含漱蔗糖溶液后咀嚼含糖口香糖和含木糖醇口香糖50min内牙菌斑pH值的动态变化。牙菌斑原位pH值的测定采用pH微电极接触法在口内直接测量。结果：含漱蔗糖溶液后5min开始咀嚼口香糖20min，可以明显提高牙菌斑pH值，使pH较快恢复至静止水平。咀嚼初期使用含糖口香糖牙菌斑pH无明显变化，而使用含木糖醇口香糖在咀嚼初期就可以明显提高牙菌斑pH至7．30。结论：含漱蔗糖溶液后，咀嚼无糖口香糖对牙菌斑的酸性产物产生明显的缓冲作用，提高菌斑pH值的作用较咀嚼含糖口香糖迅速而有效。     

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。     

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...     

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。     

Effects of frequent mouthrinses with palatinose and xylitol on dental plaque

The aim was to evaluate the effects of frequent mouthrinses with palatinose, xylitol and a mixture of palatinose and xylitol on plaque pH, plaque formation and cariogenic microorganisms. 15 subjects refrained from toothbrushing during 3 test periods and rinsed 15 × daily for 4 d with 10 nil of: (1) 50% palatinose, (2) 37.5% palatinose+ 12.5% xylitol, or (3) 50% xylitol. A contrast period with no mouthrinses was also carried out. The 4 periods were carried out in a randomized order with a cross–over design. After the 4–day periods, 3 parameters were measured: (1) plaque pH during the first 30 min after a mouthrinse with palatinose, a mixture of palatinose and xylitol or xylitol alone, directly followed by a 2nd rinse with 10% sucrose; (2) number of mutans streptococci and lactobacilli in plaque and saliva; (3) plaque index. The most pronounced pH drop for the sugar substitutes was found when rinsing with 50% palatinose after the palatinose period, and the least pH drop with 50% xylitol after the xylitol period. The sucrose rinse gave similar pH fall after all 4 periods. The microbial data showed no differences between the 4 periods, but the mutans streptococcus counts in saliva decreased after the xylitol period in contrast to the 3 other periods. Regarding the plaque index, xylitol gave lower scores compared to the other 3 periods.     

Effect of xylitol on dental plaque in vivo during carbohydrate challenge

Abstract – Xylitol has previously been shown to inhibit acid production in vitro when glucose is used as energy source, and the present studies were carried out to investigate whether this effect was valid in vivo. A solution containing both xylitol and glucose was applied on sucrose—induced 4-day-old plaque in vivo. The xylitol added to the glucose solution inhibited the acid production in the plaque, measured as a drop in pH, compared to using glucose alone. A further reduction in acidogenicity was obtained when xylitol was used as a rinse for 1 hr continuously prior to the glucose challenge.     

Does the presence of xylitol in a sorbitol-containing chewing gum affect the adaptation to sorbitol by dental plaque?

It is known that xylitol inhibits sorbitol metabolism in some bacteria in vitro. The effect of xylitol/sorbitol-containing chewing gum on sorbitol adaptation of dental plaque was therefore examined. Ten subjects used this chewing gum for 12 wk, and plaque was collected before (control plaque) and after (test plaque) the exposure to sorbitol/xylitol. The metabolism of sorbitol by the plaque was examined with ^l4C-labeled sorbitol, and the radioactive metabolites were detected by high-performance liquid chromatography (HPLC). A considerable individual variation in acid formation was found. The mean values of total acids in the test plaque increased, as compared with the control plaque. An adaptation of dental plaque to sorbitol thus occurred in spite of the presence of xylitol in the chewing gum. The concentration of acetic acid predominated over other acids in both the control and test plaques. The proportions of acids expressed in percentage of total acids differed only slightly. Thus, long-term use of xylitol/sorbitol-containing chewing gum did not eliminate the adaptation of dental plaque to sorbitol.     

Xylitol fermentation by human dental plaque

The aim of the present study was to examine xylitol metabolism by dental plaque collected immediately after the use of xylitol gum. Plaque was collected from 12 individuals immediately before and after xylitol exposure. The effect on xylitol metabolism by dental plaque of a 3 d discontinuation of the xylitol exposure was also examined. Xylitol metabolism by the plaque suspensions was initiated by adding [¹⁴C]xylitol and analyzed by HPLC. The results showed increased xylitol metabolism after 11 wk of chewing xylitol-containing gum. The ability to metabolize xylitol was rapidly reduced after the discontinuation of the xylitol exposure. It is suggested that an induction of enzymes in one or more of the species of plaque bacteria may have caused this effect. Glucose metabolism, which also was studied in the plaque samples, was decreased after xylitol exposure, but increased again 3 d after cessation of the xylitol exposure. It is suggested that the reduced glycolysis was caused by accumulation of intracellular xylitol-5-phosphate in some plaque bacteria during the xylitol exposure.     

Effect of xylitol-containing chewing gum on sorbitol metabolism in dental plaque

The aim of the present study was to examine whether a long-term use of chewing gum with xylitol as the only sweetener would affect sorbitol metabolism in dental plaque. Ten test subjects used xylitol-sweetened chewing gum for 12 weeks. Plaque was collected at three occasions; 1) Control plaque; 2) Test plaque I: plaque collected after 12 weeks of chewing xylitol-containing chewing gum; 3) Test plaque II: sucrose-stimulated plaque collected 2 d after Test plaque I was collected. Plaque suspensions were incubated with [¹⁴C]sorbitol, and uptake of sorbitol and production of sorbitol metabolites were determined by HPLC. Plaque formation and sorbitol uptake were significantly reduced.     

微型pH电极的制备及其在牙菌斑pH检测中的应用

目的研制可用于牙菌斑pH原位检测的化学修饰性微型pH电极。方法采用氧化铱为氢离子敏感膜,以极化电解的方式将敏感膜附着于铂丝上,制备铂-氧化铱化学修改性微型pH电极,筛选性能优良的电极用于菌斑pH的原位检测,并与蜂式微型pH电极的检测进行对比。结果自制电极在pH值为1~11范围内呈线性响应,斜率为55.8mV/pH,响应时间为15~20s,电极在8h内的漂移为0.5~1.0mV,使用寿命大于1年。在对牙菌斑pH的原位检测中,自制电极与蜂式pH电极在漱糖后1h内各时间点测得的菌斑pH值差异均无显著性(P>0.05)。结论自制的铂-氧化铱化学修饰性微型pH电极对H+选择性好、性能稳定、响应范围广、响应时间短,在牙菌斑pH的原位检测中显示了良好的可行性。     

木糖醇牙膏对菌斑抑制效果的临床试验

目的:评价木糖醇牙膏在抑制菌斑生成的临床效果。方法: 60名军校学员随机分为3组,即黑妹木糖醇牙膏组、黑妹空白牙膏组、高露洁全效牙膏组,双盲法评价1周和4周后的刷牙效果。结果:使用木糖醇牙膏4周后,试验组全口平均菌斑指数持续下降,第4周与第1周比较P<0. 01。1周后,三组菌斑清除率无显著性差异; 4周后,黑妹木糖醇牙膏组平均菌斑清除率最高。黑妹木糖醇牙膏组与高露洁全效牙膏组菌斑清除率无显著性差别,而与黑妹空白牙膏组比较有显著性差异。结论:长期使用木糖醇牙膏能显著抑制牙菌斑形成,黑妹木糖醇牙膏与高露洁全效牙膏抑菌效果相当,均优于不含木糖醇的空白牙膏。     

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