唾液对牙釉质酸蚀保护作用的体外实验研究

目的 研究酸蚀症儿童唾液和无酸蚀症儿童唾液对牙釉质酸蚀的保护作用及程度.方法 收集5名患酸蚀症男童和5名无酸蚀症男童非刺激性唾液各10 ml.收集因正畸需要而新鲜拔除的健康青少年前磨牙15个,制备牙釉质块30个,随机分成酸蚀症唾液组、无酸蚀症唾液组和去离子水组3组.釉质样本分别浸泡在唾液和去离子水内,每天2次用0.3%的枸橼酸溶液酸蚀5 min,10 d循环结束后,用原子力显微镜观察釉质表面粗糙度以及显微硬度计进行釉质硬度测量.结果 去离子水组的釉质样本表面粗糙度大于两个唾液组釉质样本,显微硬度值小于两个唾液组的釉质样本(P<0.00 1).酸蚀症唾液组和无酸蚀症唾液组釉质样本的表面粗糙度值和显微硬度值间差异均无统计学意义(P=0.695,P=0.432).结论 唾液对牙釉质酸蚀起到保护作用,有无患酸蚀症的儿童唾液对牙釉质的保护作用无差异.     

武汉市3～5岁儿童牙齿酸蚀症的研究

目的：调查武汉市3～5岁儿童的酸蚀症流行状况；评价儿童饮用饮料和饮食习惯、口腔卫生习惯与酸蚀症的关系。方法：随机抽样武汉市4所幼儿园3～5岁儿童共500人。对所有儿童进行酸蚀症和龋齿发病情况的临床检查以及问卷调查，问卷内容包括：儿童每天消耗饮料或食物的频率，以及口腔健康行为。收集酸蚀症儿童和无酸蚀症儿童各20人，对其唾液pH值、流速和缓冲能力进行测定和比较。结果：武汉市3—5岁儿童酸蚀症的患病率为9．3％。儿童睡觉时含奶瓶、喝饮料的习惯与酸蚀症的发生呈正相关。酸蚀症儿童和对照组儿童唾液分析结果无显著性差异。结论：预防酸蚀症应该减少酸性食物及饮料的消费量及频率。     

影响儿童牙齿酸蚀症的唾液因素

本研究的目的是测量酸蚀症儿童的唾液流率、缓冲力和变形链球菌的数目,并与同年龄、性别的无龋和龋活跃个体比较,以确定酸蚀症的重要危险因素。 材料和方法 实验组选择3～16岁常规检查出酸蚀症的103个儿童,对照组为年龄、性别匹配的儿童组成的无龋组和龋活跃组。所有试验对象唾液收集均在早晨及相对安静的环境中进行,采集前2h禁食禁饮,测定唾液变链菌数、菌斑pH值、唾液流率和唾液pH值、缓冲力。变链菌用压舌板法采集后接种于培养皿,以Joyce Loebel Magiscan分析系统计数。非刺激性唾液收集时,儿童取坐位,低头流入     

唾液检测用于龋病风险性评估的研究进展

唾液是牙齿的外环境。龋病是牙体硬组织发生的慢性进行性破坏性疾病。唾液有机成分、无机成分、缓冲能力及流速流量的改变与龋病风险性有着密切关系。通过唾液检测技术能够发现早期龋损，有助于龋病的早期诊断，为龋高危人群的监控提供重要的信息。国外近年来唾液检测技术发展迅速。本文就唾液检测用于龋病风险性评估的研究进展作一综述。     

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近十余年来,牙酸蚀症患病率不断上升,已成为一个新的口腔健康问题。各国学者进行了大量的调查和研究,认为牙酸蚀症是一种多因素的疾病,是化学、生物、行为等多种因素相互影响、相互作用的结果。对于牙酸蚀症的易感人群,应对其饮食习惯、口腔卫生习惯、牙齿结构、唾液及获得性膜等方面进行风险评估,并综合分析各项评估结果,以利于诊断和为不同风险级别的易感者制定全面的预防策略。     

006.影响儿童牙齿酸蚀症的唾液因素

[英]/O＇Sulli van EA…∥Caries Res.-2000,34.-82～87 本研究的目的是测量酸蚀症儿童的唾液流率、 缓冲力和变形链球菌的数目,并与同年龄、性别的无 龋和龋活跃个体比较,以确定酸蚀症的重要危险因 素. 材料和方法实验组选择3～16岁常规检查出 酸蚀症的103个儿童,对照组为年龄、性别匹配的儿 童组成的无龋组和龋活跃组.所有试验对象唾液收 集均在早晨及相对安静的环境中进行,采集前2 h 禁食禁饮,测定唾液变链菌数、菌斑pH值、唾液流 率和唾液pH值、缓冲力.变链菌用压舌板法采集 后接种于培养皿,以Joyce Loebel Magiscan分析系统 计数.非刺激性唾液收集时,儿童取坐位,低头流入 刻度管5 min;刺激性唾液收集时,儿童在咀嚼1 g石 蜡后吐入刻度管3 min.唾液流率、pH值、变链菌计 数的差异性用单因素方差分析,唾液缓冲力用卡方 检验.计算各因素的未校正概率,评估其危险性,大 于95%认为相关. 结果刺激性唾液流率增高,pH值增高(仅 有0.3个单位提高).试验组约一半刺激性唾液缓 冲力低.变链菌平均计数:试验组大于龋活跃组大 于无龋组(实验组与对照组比较P=0.05).无龋组 唾液流率最高,但与其他两组比较差异无显著性. pH值则无龋组大于龋活跃组大于试验组,差异有显 著性(P＜0.001).唾液缓冲力为试验组低缓冲力 的个体百分数最高,各组间差异有极显著性(P＜ 0.001).表明变链菌数、刺激性和非刺激性唾液的 pH值、缓冲力是酸蚀症的危险因素,非刺激性唾液 pH值低于6.5则酸蚀症易感性提高5倍,低缓冲力 可提高易感性2倍. [杨德琴摘刘天佳校]     

控制牙齿酸蚀症的研究进展

牙齿酸蚀症是指在没有细菌参与的情况下,由化学因素引起的牙体硬组织慢性、不可逆性破坏的疾病。此疾病在人群中普遍存在。控制酸蚀症的发生和发展是口腔临床工作的难点,正日益受到研究者的关注。本文就酸蚀症的早期诊断、风险评估及预防策略的研究进展作一综述。     

自酸蚀粘结系统及唾液污染分别对窝沟封闭剂微拉伸粘结强度的影响

目的 评价Clearfil S3 Bond自酸蚀粘结系统和唾液污染对窝沟封闭剂拉伸粘结强度的影响.方法 15颗离体前磨牙,随机分为3组,每组5颗.A、B组分别经35%磷酸酸蚀、Clearfil S3 Bond自酸蚀处理,C组35%磷酸酸蚀后唾液污染,3组均用Estiseal F窝沟封闭剂分层固化堆积形成5 mm高封闭剂小柱.再将样本切成1 mm×1 mm×10 mm大小的试件,微拉伸仪检测其拉伸粘结强度.结果 使用自酸蚀粘结系统与常规磷酸酸蚀组的微拉伸粘结强度无显著区别(P＞0.05),而唾液污染组显著低于常规磷酸酸蚀组的微拉伸粘结强度(P＜0.05).结论 临床操作过程中应严格避免唾液污染,而关于自酸蚀粘结剂对封闭剂与牙釉质的微拉伸粘结强度的影响需进一步研究.     

一种新型自酸蚀剂对托槽粘结强度的影响

目的 :探讨一种新型自酸蚀剂对托槽粘结强度的影响。方法 :收集人离体前磨牙 10 5个 ,随机分成 7组。 1组 :3 5 %磷酸酸蚀 3 0s ,去离子水冲洗 ,吹干 ;涂粘结剂 ,TransbondXT光固化复合树脂粘贴托槽。 2组、3组和 4组分别在涂自酸蚀剂 3s内、2min和 15min后粘贴托槽。 5组涂自酸蚀剂后 ,再涂一层唾液粘贴托槽 ;6组依次涂唾液、自酸蚀剂后粘贴托槽 ;7组涂唾液、自酸蚀剂、唾液后粘贴托槽。所有试件均于常温去离子水内放置2 4h ,测试抗剪切强度 ,观察断面形态。结果 :4组的抗剪切强度最高。 5组和 7组的抗剪切强度显著低于其它组。断面形态观察 ,结果显示抗剪切强度高的组别在托槽与复合树脂之间发生断裂 ;抗剪切强度低的组别在牙齿与复合树脂之间发生断裂。结论 :该自酸蚀剂能获得与磷酸酸蚀相同的粘结强度 ,且发生断裂不受操作时间的影响 ,但在操作时间内应防止唾液污染。     

徐州市5岁和12岁儿童酸蚀症调查研究

目的了解徐州市儿童酸蚀症的流行情况。方法采用分层整群随机抽样方法,抽取徐州市1 219名5岁儿童和786名12岁儿童进行酸蚀症流行病学调查。通过调查表记录酸蚀症的临床检查结果,调查问卷调查酸蚀症的危险因素。采用Logistic多元回归分析酸蚀症的危险因素。结果徐州市5岁儿童牙齿酸蚀症的患病率为10.91%,12岁儿童牙齿酸蚀症的患病率为22.14%。酸蚀症的等级多为1级和2级,3级以上的酸蚀症极少。酸蚀症危险因素的比值比（OR）分别为：酸性水果,1.120;酸奶,1.062;运动饮料,1.159;碳酸饮料,1.151;果汁,1.187;睡前喝酸性饮料或酸奶,6.102;胃食道返流性疾病,2.311;维生素C,1.565;补铁剂,1.598。结论我国儿童牙齿酸蚀症已广泛存在,今后应加强口腔卫生教育和饮食指导,减少酸性食品和饮料的摄入量和摄入频率,促进口腔健康。     

Erosion--diagnosis and risk factors

Dental erosion is a multifactorial condition: The interplay of chemical, biological and behavioural factors is crucial and helps explain why some individuals exhibit more erosion than others. The erosive potential of erosive agents like acidic drinks or foodstuffs depends on chemical factors, e.g. pH, titratable acidity, mineral content, clearance on tooth surface and on its calcium-chelation properties. Biological factors such as saliva, acquired pellicle, tooth structure and positioning in relation to soft tissues and tongue are related to the pathogenesis of dental erosion. Furthermore, behavioural factors like eating and drinking habits, regular exercise with dehydration and decrease of salivary flow, excessive oral hygiene and, on the other side, an unhealthy lifestyle, e.g. chronic alcoholism, are predisposing factors for dental erosion. There is some evidence that dental erosion is growing steadily. To prevent further progression, it is important to detect this condition as early as possible. Dentists have to know the clinical appearance and possible signs of progression of erosive lesions and their causes such that adequate preventive and, if necessary, therapeutic measures can be initiated. The clinical examination has to be done systematically, and a comprehensive case history should be undertaken such that all risk factors will be revealed.     

Factors affecting intra‐oral pH – a review

One of the greatest challenges to modern dentistry is the progressive destruction of tooth material due to chemical erosion. Dental erosion is the loss of dental hard tissue, without the action of bacteria, in which demineralisation of enamel and dentine results due to a decrease in intra‐oral pH. The aim of this review was to appraise the scientific literature on the factors that can affect intra‐oral pH. The review will examine (i) the protective role of human saliva, in terms of its mineral composition, flow rates and buffering systems and (ii) sources of in‐mouth acids such as extrinsic acids, which are derived from the diet and environment, as well as intrinsic acids, which are related to disorders of the gastro‐oesophageal tract. This review may assist clinicians to identify the risk factors for tooth wear and to recommend adequate preventive measures to patients.     

The role of diet in the aetiology of dental erosion

Acids of intrinsic and extrinsic origin are thought to be the main etiologic factors for dental erosion. There is evidence that acidic foodstuffs and beverages play a role in the development of erosion. However, the pH of a dietary substance alone is not predictive of its potential to cause erosion as other factors modify the erosive process. These factors are chemical (pKa values, adhesion and chelating properties, calcium, phosphate and fluoride content), behavioural (eating and drinking habits, life style, excessive consumption of acids) and biological (flow rate, buffering capacity, composition of saliva, pellicle formation, tooth composition, dental and soft tissue anatomy). The interplay between erosion and abrasion (specially oral hygiene practices) may be the main driver leading to the clinical manifestation of this disorder. Recommendations for patients at risk for dental erosion such as reducing acid exposure by reducing the frequency and contact of acids will be discussed.     

Saliva and dental erosion

Dental erosion is a multifactorial condition. The consideration of chemical, biological and behavioral factors is fundamental for its prevention and therapy. Among the biological factors, saliva is one of the most important parameters in the protection against erosive wear.

Objective

This review discusses the role of salivary factors on the development of dental erosion.

Material and Methods

A search was undertaken on MEDLINE website for papers from 1969 to 2010. The keywords used in the research were "saliva", "acquired pellicle", "salivary flow", "salivary buffering capacity" and "dental erosion". Inclusion of studies, data extraction and quality assessment were undertaken independently and in duplicate by two members of the review team. Disagreements were solved by discussion and consensus or by a third party.

Results

Several characteristics and properties of saliva play an important role in dental erosion. Salivary clearance gradually eliminates the acids through swallowing and saliva presents buffering capacity causing neutralization and buffering of dietary acids. Salivary flow allows dilution of the acids. In addition, saliva is supersaturated with respect to tooth mineral, providing calcium, phosphate and fluoride necessary for remineralization after an erosive challenge. Furthermore, many proteins present in saliva and acquired pellicle play an important role in dental erosion.

Conclusions

Saliva is the most important biological factor affecting the progression of dental erosion. Knowledge of its components and properties involved in this protective role can drive the development of preventive measures targeting to enhance its known beneficial effects.     

Managing dental erosion

The clinical signs of dental erosion are initially subtle, yet often progress because the patient remains asymptomatic, unaware and uninformed. Erosion typically works synergistically with abrasion and attrition to cause loss of tooth structure, making diagnosis and management complex. The purpose of this article is to outline clinical examples of patients with dental erosion that highlight the strategy of early identification, patient education and conservative restorative management. Dental erosion is defined as the pathologic chronic loss of dental hard tissues as a result of the chemical influence of exogenous or endogenous acids without bacterial involvement. Like caries or periodontal disease, erosion has a multifactorial etiology and requires a thorough history and examination for diagnosis. It also requires patient understanding and compliance for improved outcomes. Erosion can affect the loss of tooth structure in isolation of other cofactors, but most often works in synergy with abrasion and attrition in the loss of tooth structure (Table 1). Although erosion is thought to be an underlying etiology of dentin sensitivity, erosion and loss of tooth structure often occurs with few symptoms. The purpose of this article is threefold: first, to outline existing barriers that may limit early management of dental erosion. Second, to review the clinical assessment required to establish a diagnosis of erosion. And third, to outline clinical examples that review options to restore lost tooth structure. The authors have included illustrations they hope will be used to improve patient understanding and motivation in the early management of dental erosion.     

In vitro remineralisation of eroded enamel lesions by saliva

OBJECTIVES: It is speculated that saliva, with its mineral content, may possess a reparative effect on an early erosion which is characterised by softened surface and slight subsurface demineralisation in addition to a crater. This study aimed to determine the possible remineralisation of early enamel erosion by saliva. METHODS: Eroded lesions were produced in bovine incisors by 1-h immersion in orange juice. Control sections and three experimental slabs were produced from each tooth. The three slabs were assigned randomly to one of three remineralising agents: clarified natural saliva (NS), artificial saliva (AS) and remineralising solution (RS). All solutions had a pH of 7.2, a fluoride concentration of 0.022 ppm, and were changed daily. NS was collected daily from the same individual at the same time of day. The specimens were exposed to their respective remineralising agents for 28 days. Using microradiography and image analysis, the mineral loss (Delta z) and lesion depth (ld) were quantified in sections cut from the control and experimental slabs. RESULTS: A significant (p<0.001) amount of mineral was gained following exposure to each remineralising agent. Significantly less Delta z and ld were observed for the experimental groups compared with the control group (p<0.001; paired t-test). This effect was greatest with RS and least with AS. Inter-group comparison (Duncan multiple tests) showed no significant difference in Delta z among the experimental groups, however ld was significantly higher for AS (p<0.001) compared with RS and NS, and no difference was observed between RS and NS. CONCLUSION: Saliva as well as remineralising solutions can remineralise early enamel erosion.     

Erosive tooth wear: prevalence and severity in Swedish winetasters

Full-time Swedish winetasters test on average 20–50 different wines, nearly 5 days a week. As the pH of wines ranges from 3.0 to 3.6, there is a potential risk for tooth erosion. The aims of this study were to document the prevalence and seventy of tooth erosion in qualified winetasters in relation to number of years of winetasting. salivary flow rate, and buffer capacity. The subjects comprised all 19 qualified winetasters (7 women and 12 men. aged 29–64 years employed in Stockholm by Vin & Sprit AB. the state-owned company-marketing nines and spirits. At intraoral examination, tooth surface loss was registered and documented by photography. Salivary flow rate and buffer capacity of unstimulated and stimulated saliva were measured. Data on occupational background and dental and medical histories were collected. Fourteen subjects had tooth erosion, the severity varying from mild to extreme, mainly on the labiocervical surfaces of maxillary incisors and canines. The severity of the erosion tended to increase with years of occupational exposure. Caries activity in all subjects was low. 14 subjects had low unstimulated salivary flow rates. It was concluded that full-time winetasting is an occupation associated with increased risk for tooth erosion.     

Eroded enamel lesion remineralization by saliva as a possible factor in the site-specificity of human dental erosion

The composition and flow of saliva, which determine its functions, vary within intraoral sites and among individuals. Also, the susceptibility to tooth erosion reportedly varies among individuals and within the dental arches. A possible effect of saliva on early-eroded lesions may be a contributory factor. The aims here were firstly to determine the remineralization of eroded enamel lesions by saliva, and secondly to investigate any variation of this remineralization within the dental arches and among individuals. Early enamel erosion was produced on human premolars using orange juice. Control sections and two test slabs were cut from each tooth. The two slabs from the same lesion were bonded with composite resins to the palatal surface of upper right lateral incisor teeth and the lingual surface of the lower right lateral incisor teeth of volunteers, who then chewed a sugar-free gum four times daily. After 28-day intraoral exposure, mineral loss (DeltaZ) and lesion depth (ld) were quantified using microradiography and the data analysed by paired t-test (n=10, alpha=0.05). Mean DeltaZ was significantly lower in the group of slabs positioned palatally (P<0.001) and lingually (P<0.001) when compared with the control group, and in the lingually placed group when compared with the palatally positioned (P<0.01). A significantly lower ld was observed in the group of slabs positioned palatally (P<0.05) and lingually (P<0.001) when compared with the control group, and in the lingually positioned group when compared with the palatally placed (P<0.05). It was concluded that saliva can remineralize early enamel erosion, and that the degree of remineralization varies within intraoral sites and may be responsible for the differing susceptibility to erosion within the dental arches.     

Interaction of salivary fibronectin with oral streptococci

Immunoreactive Fibronectin (Fn) has been demonstrated in stimulated human parotid saliva by western blot analysis and also found to be a component of the artificial tooth pellicles derived from hydroxyapatite (HA) beads coated with parotid saliva. Saliva depleted of gelatin-binding components showed a significantly lower degree of reactivity with anti-Fn antibodies than did the control saliva when tested by and enzyme-linked immunosorbent assay (ELISA). Depletion of gelatin-binding components from saliva was also found to affect the degree of saliva-mediated aggregation of four of the seven oral streptococci tested [Streptococcus mutans strains GS-5 and OMZ 176, S. sobrinus, and S. rattus]. Similarly, the adherence of the same four micro-organisms to the artificial tooth pellicles (derived form saliva which had previously been depleted of gelatin-binding component) was significantly inhibited (37-53%) when compared with the control saliva-coated HA beads. Pre-treatment of streptococci with 100 micrograms of soluble Fn also caused a 34-57% inhibition of adherence of the same oral streptococci to saliva-treated HA beads. Quantitation of Fn in human parotid saliva showed that the amounts of immunoreactive Fn varied form 2 to 6 micrograms/mL of parotid saliva. Furthermore, the Fn from parotid saliva was found to be adsorbed onto the bacterial surfaces, as demonstrated by immunofluorescence and ELISA. The presence of Fn in parotid saliva and its ability to bind to HA beads (artificial pellicles), in conjunction with the ability of soluble Fn to inhibit the adherence of streptococcal strains to the artificial tooth pellicles, suggest that the microbial ecology of the oral cavity may, in part, be influenced by the interactions mediated by salivary fibronectin.