牙齿硬组织脱矿与再矿化的研究方法

龋病是口腔微生物引起的牙齿硬组织疾病,在龋病发生中,脱矿与再矿化常常同时或者交替发生,对脱矿与再矿化进行定性或定量的检测是龋病研究的必要手段.本文就评估牙齿硬组织脱矿与再矿化的各种研究方法及其优缺点作一综述.     

牙齿脱矿和再矿化检测方法的研究进展

早期龋可以通过再矿化的措施使龋病终止和逆转,而传统的龋病诊断方法难以检测临床损害前期及非常早期的损害。为实现早期脱矿的准确诊断,许多脱矿和再矿化的检测方法被不断开发和完善。本文主要介绍目前一些检测方法包括横向x射线显微照相术、增强肉眼检查、电阻抗技术、数字放射减影技术、显微硬度检查方法、激光荧光检查方法、定量光导荧光技术、光纤维透照技术、共聚焦激光扫描显微镜检查、光学相干计算机断层摄影术并进行评价。     

五倍子防龋的研究进展

五倍子有抑制主要致龋菌生长,黏附,产酸的作用,能抑制菌斑生长,抑制牙体硬组织脱矿和促进再矿化.讨论了五倍子在龋病防治中的作用,对进一步研究方向进行展望.     

牙齿硬组织脱矿与再矿化的研究方法

龋病是口腔微生物引起的牙齿硬组织疾病，在龋病发生中，脱矿与再矿化常常同时或者交替发生，对脱矿与再矿化进行定性或定量的检测是龋病研究的必要手段。本文就评估牙齿硬组织脱矿与再矿化的各种研究方法及其优缺点作一综述。     

含硅再矿化液中硅含量对脱矿牙釉质再矿化影响研究

目的    观察不同质量分数含硅再矿化液对脱矿牙釉质表面微观形貌的影响,探讨其对脱矿牙釉质的再矿化作用。方法    本研究于2014年4—8月在吉林大学口腔医院实验室进行。将牙釉质标本置于乳酸人工脱矿液中浸泡1周形成人工釉质龋,扫描电镜（SEM）观察确认人工釉质龋形成后,将脱矿釉质块随机分为5组,分别置于基础再矿化液（对照组）及含硅质量分数为0.5 × 10-6、1 × 10-6、8 × 10-6、16 × 10-6的再矿化液（实验组）中进行再矿化处理3周,SEM观察处理后人工釉质龋脱矿釉质表面的再矿化效果。结果    不同浓度含硅再矿化液都有促进脱矿釉质再矿化的作用,其中以含硅质量分数为8 × 10-6的再矿化液效果最为显著。当含硅质量分数为0.5 × 10-6  、1 × 10-6和8 × 10-6时,随着硅含量的增加脱矿牙釉质的再矿化程度增高;当含硅质量分数上升为16 × 10-6时,其再矿化程度则有所下降。结论    硅能够促进脱矿牙釉质再矿化,并且以再矿化液含硅质量分数为8 × 10-6的再矿化效果最为显著。     

硅对人恒前磨牙早期釉质龋再矿化影响的扫描电镜观察

目的:借助扫描电镜观察硅对脱矿釉质再矿化的影响.方法:用基础再矿化液和加硅的再矿化液对脱矿后的离体恒前磨牙牙釉质标本进行再矿化处理,用扫描电镜观察其表面形态及组织学变化.结果:对照组蜂巢状结构清晰,凹陷底部见球状沉积物,已变浅.实验组蜂巢状结构不清晰,大量微球状和球状颗粒沉积,凹陷变浅,有的地方已经填平,呈光滑形态.结...     

龋患风险预测的方法

龋病是多因素引起的疾病,通过检测个体的各龋危因素或再矿化潜能,测得个体的患龋风险的大小,从而采取针对病因的预防措施可以减少龋病的发病率。本文就龋患风险预测内容及方法作一简要综述。     

龋病治疗药物的研究进展

龋病被世界卫生组织列为三大重点防治疾病之一。通过再矿化手段修复受损牙体硬组织被认为是一种极具潜力的龋病治疗策略,但是当前的再矿化技术主要是基于离体牙模型研究发展起来的,忽视了天然龋的病理结构特点和生物膜的影响,缺少针对天然龋治疗效果的进一步验证和转化,尚不能精准有效地预防和治疗龋病。基于此,近期部分研究开始着重于设计具有抗菌和再矿化双功能的复合材料,从龋病的病理特点出发,采取更高效的手段以终止龋病的进展。本文综述了目前无创/微创终止龋病的临床治疗技术和相关材料学研究进展,并且展望了未来再矿化/抗生物膜双功能材料精准预防和治疗龋病的研究方向和思路。     

氟对脱矿和再矿化牙釉质表面的影响

目的研究氟对脱矿和再矿化牙釉质表面的影响,探讨氟防龋的作用机理。方法将牛牙釉质标本分为空白对照组（A组）、非氟化组（B组）、低氟化组（C组）和高氟化组（D组）4组,其中低氟化组和高氟化组依次进行氟化实验、脱矿实验和pH循环再矿化实验,非氟化组只进行脱矿实验和pH循环再矿化实验,空白对照组不做处理。在体视显微镜、显微硬度计和扫描电镜下观察各组釉质表面的形态变化,同时测量分析釉质表面显微硬度。结果氟化牙釉质的表面微观形态显著不同,其脱矿损害具有相对完整的表层;氟化组在氟化、脱矿和再矿化后与非氟化组相比,表面显微硬度均有统计学差异（P<0.05）。结论氟化牙釉质可增强牙釉质的抗龋能力和再矿化效能。     

多乐氟促进乳牙脱矿后再矿化的研究

目的：观察多乐氟在乳牙光滑面脱矿后再矿化的效果。方法：选择3~6岁上颌乳前牙唇面脱矿患儿35例,120颗乳前牙纳入研究,每组各60颗患牙,观察组每半年涂布一次多乐氟,研究期间采用Bass刷牙法,对照组仅采用Bass刷牙法,每半年复查,观察脱矿牙面的变化。结果：6个月和1年时两组成功率差异无统计学意义,18个月时涂氟组再矿化成功率高于单纯刷牙组。结论：涂布多乐氟促进脱矿牙面再矿化是一种安全有效、使用便捷的方法。     

Assessment of caries activity and caries risk

This paper reviews the present knowledge regarding methods of caries prediction. The clinician's ability to predict caries by examination and on the basis of knowledge of patient's attitude and background functions relatively well. Bacterial and salivary tests do not contribute significantly to this. The caries present at the moment of examination, the cariesexperience, is the best predictor of caries among children.     

Effect of intensified caries prevention on approximal caries in adolescents with high caries risk.

The aim of this study was to evaluate the effect of two preventive programs carried out in Public Dental Clinics for children with high caries risk. From all the 13-year-olds living in Kuopio (n = 871), 323 (37%) were selected as a high-risk group on the basis of the level of salivary mutans streptococci or DS score. They were randomly divided into two groups. The first group continued with the preventive care they had received before the study. The dentists treating the children in the second group were specifically informed about their high caries risk, and instructions concerning intensified prevention were given. For comparison, half of the 13-year-olds with low caries risk were included in the study (group 3, n = 248). No special instructions concerning these children were given. After 2 years, approximal caries increment in the two risk groups was three times that of the low-risk group (2.6, 2.3 and 0.7 in groups 1-3, respectively). There was no significant difference between the two risk groups in spite of the fact that significantly more preventive procedures were provided for group 2 than for group 1. The results indicate that assessment of the subjects as high and low-risk groups was successful, but caries prevention targeted for the risk groups failed to lower the rate of caries to the same level as that of the children with an anticipated low risk. For children at high risk, the intensified prevention program monitored by dental authorities was no more successful than prevention planned by individual dentists.     

The relationships between prevalence of caries, percentage with active caries, and caries severity

The specification of the relationships between prevalence of caries, percentage of children with active caries, and caries severity improves our understanding of the distribution and extent of caries as well as providing a method of predicting one from another. Using recent Australian data these relationships were investigated and specified. A catalytic equation best fitted the relationship between prevalence of caries and caries severity. A mixed-multiplicative equation best fitted the relationship between percentage with active caries and caries severity. The specifications of these relationships appeared sensitive to changes in the distribution and extent of caries over time. However, the magnitude of the changes occurring differs between the three measures. This may have contributed to the late recognition of the changing pattern of caries and may have implications for the delivery of dental services.     

Prognosis of caries increment with past caries experience variables

This study aimed to select past caries experience variables as caries predictors and to compare their prognostic accuracy with the variables used in a method of caries prognosis developed in a Swiss child population. The data used for the analyses originated from an 8-year longitudinal study starting in 1980 on caries of 7.5-year-old Dutch children. Stepwise logistic regression analyses provided predictor variables. The newly introduced variables D23fi, D(123)i and D23pifi were interchangeable and the most powerful caries predictors. For the sake of uniformity and ease of application, D23fi (number of fissures of the permanent first molar with non-cavitated or cavitated caries lesions) was chosen as the first variable in the logistic regression equations. The gain in accuracy of the second and third predictor variables (number of sound primary molars and the number of buccal and lingual smooth surfaces of the permanent first molar with non-cavitated or cavitated caries) in the regression equations was limited. The D1 condition of surfaces could be omitted from the prediction models. The present forced three-predictor-regression equations for 7.5-, 9.5- and 11.5-year-old children were evaluated to assess their prognostic performance by using the area under the ROC curve as a measure of prognostic quality. For the present regression equations, the area under the ROC curve was 81-87%, which was higher compared to the Swiss regression equations for caries prognosis.     

Actual caries development compared with expected caries activity

abstract In 18 schoolboys, 16 years old, the actual caries development during 1 year was compared with the expected caries activity which was predicted from evaluations of four selected tests: (1) the buffer capacity, (2) the titer of Streptococcus mutans in stimulated whole saliva, (3) clinical evaluation of rate of plaque formation, and (4) a quantitation of a salivary agglutinin reacting with a serotype c strain of S. mutans. According to previous experiences the estimated value for each factor was classified for each individual either as a negative (caries-provoking) or as a non-negative factor. The score of negative factors could thus vary between 0 and 4 for each individual. A good relationship was observed between the caries increment during 1 year and the sum of the scores from the tests representing expected caries activity. This observation indicates the possibility of selecting the most caries susceptible individuals in a population by using the four parameters. A selection can be made from two or three of the tests but then the degree of differentiation becomes lower. No parameter could singly be used as an indication of the potential caries activity in the individual test.     

Frequency of radiographic caries examinations and development of dental caries

The general aim of this thesis was to evaluate whether a change in the threshold for surgical intervention in the caries process can be consistent with a stricter attitude towards the use of radiographic caries diagnosis. Bitewing radiographs of 3 groups of patients were retrospectively studied. Two groups comprised 229 patients, 18 years old at the end of the study in 1984. 102 had lived in an area with 1.2 ppm water-fluoride content (F84-group) and 127 in an area with 0.02 ppm fluoride content (O84-group). In the 3rd group 285 patients, 19 years old at the end of the study in 1993, lived in an area with 1.2 ppm water-fluoride content (F93-group). The latter patients were managed according to a restrictive attitude to surgical intervention and radiographic diagnosis of caries. The prevalence of patients and the frequency of tooth surfaces with caries was significantly lower in the fluoride groups than in the non-fluoride group. The correlation between patients' accumulated number of posterior proximal lesions and fillings at the last examination and the mean interval between their bitewing examinations was weak in all groups. The mean interval between examinations was significantly longer in the F93-group than in the other 2 groups. By applying an algorithm for individualisation of examination intervals these could be prolonged depending on the accepted risk for the development of inner dentin lesions. Future development of proximal dentin lesions was rather well predicted by means of past caries experience as demonstrated by ROC-analysis. The proportion of inner dentin lesions that were operatively treated was significantly higher in patients from the F93-group than in those from the other 2 groups in which a less strict attitude towards operative treatment was used. In the F93-group the average survival time of enamel and outer dentin lesions was 8.0 and 3.4 years, respectively, when right censored data were taken into account. In populations with low caries prevalence a strict threshold for operative treatment of proximal lesions can be consistent with prolonged intervals between radiographic examinations without an increased risk of pulp involvement. A skewed distribution of the patients with regard to caries experience was found in all 3 groups. Thus, even in low prevalence populations the intervals between radiographic examinations must be individually determined and coupled with individualised preventive care.