UNASSIGNED: Human root dentine samples (150) were randomly divided into five experimental protocols of 30 specimens each: 1) fluoride varnish (22,600 ppm fluoride and 1-5% CPP-ACP); 2) fluoride varnish followed by Paste One (1100 ppm sodium fluoride and CPP-ACP); 3) fluoride varnish followed by Paste Plus (900 ppm sodium fluoride and CPP-ACP); 4) fluoride varnish followed by Paste One and Paste Plus; and 5) no treatment (control). A layer of varnish was applied to specimens except the control group and was left in situ for 18 h. The varnish layer was removed, and the various toothpaste treatments were initiated. Half of the specimens in each group were assigned to a short-term incubation model in which they were immediately subjected to a 7-day cariogenic challenge consisting of a combination of human saliva and artificial saliva containing 2% sucrose. The other half of the specimens in each group were assigned to the long-term incubation model in which the experimental protocol was continued for 8 weeks before initiating the seven-day cariogenic challenge. The protocols were evaluated by assessing dentine porosity (rhodamine intensity), mineral density, biofilm biomass, and viability assays.
METHODS: Confocal laser scanning microscopy was used to determine dentine porosity and Levene\'s test was used to verify the assumption of equality of variances and normal distribution of errors before two-way ANOVA and the Games-Howell test were carried out at a significance level of 0.05 for both incubation models. Microcomputed tomography was used to determine mineral density with statistical analysis involving Levene\'s test, two-way ANOVA and Tukey\'s test at a significance level of 0.05 for both incubation models. Biomass was evaluated using a biofilm biomass assay with analysis of optical density data using Levene\'s test, ANOVA and Scheffe\'s test at a significance level of 0.05.
RESULTS: For both the short- and long-term incubation models, all the experimental regimes resulted in a statistically significant decrease in dentine porosity and an increase in mineral density when compared to the control group. Fluoride varnish followed by both pastes and fluoride varnish followed by Paste One resulted in a statistically significant decrease in dentine porosity for some depths in both models when compared to fluoride varnish alone. Changes in dentine porosity and mineral density were observed within groups over time. All the experimental regimes demonstrated anti-biofilm effects. Immediate and sustained anti-caries effects were observed for all preventive protocols, with the combination of fluoride varnish and Paste One resulting in superior additional anti-caries effects.
CONCLUSIONS: The authors concluded that all protocols demonstrated immediate and sustained anti-caries effects against the development of root caries despite variations in effects over time. The combination of fluoride varnish and Paste One resulted in additional anti-caries effects that were consistently superior, with no additional effects being observed when Paste Plus was added in combination. The authors suggest that, within the study\'s limitations, topical fluoride varnish seems to have a protective effect on root surfaces for up to eight weeks and that fluoride varnish should be considered as an important adjunct strategy in the prevention of root caries in older adults.
■将人根部牙本质样品(150)随机分为五个实验方案,每个实验方案30个:1)氟化物清漆(22,600ppm氟化物和1-5%CPP-ACP);2)氟化物清漆,然后是糊状1(1100ppm氟化钠和CPP-ACP);3)氟化物清漆,然后是糊状加(900ppm氟化钠和P-ACP糊状)除对照组外,将一层清漆涂在样品上,并在原位放置18小时。去除清漆层,并开始了各种牙膏治疗。每组中的一半样本被分配到短期孵育模型中,在该模型中,它们立即经受7天的致龋攻击,该攻击由人唾液和含有2%蔗糖的人工唾液的组合组成。每组中的另一半样本被分配到长期孵育模型,其中实验方案在开始七天致龋攻击之前持续8周。通过评估牙本质孔隙率(罗丹明强度)来评估方案,矿物密度,生物膜生物量,和活力测定。
方法:使用共聚焦激光扫描显微镜来确定牙本质的孔隙率,并使用Levene检验来验证方差相等和误差正态分布的假设。显微计算机断层扫描用于确定矿物密度,统计分析涉及Levene的测试,两种孵育模型的显著性水平均为0.05的双向方差分析和Tukey检验。生物质使用生物膜生物质测定进行评估,并使用Levene测试分析光密度数据,方差分析和Scheffe检验的显著性水平为0.05。
结果:对于短期和长期孵化模型,与对照组相比,所有实验方案均导致牙本质孔隙率的统计学显着降低和矿物质密度的增加。与单独的氟化物清漆相比,在两种模型的某些深度下,氟化物清漆随后是糊剂1,导致牙本质孔隙率在统计学上显着降低。随着时间的推移,组内观察到牙本质孔隙率和矿物质密度的变化。所有实验方案都证明了抗生物膜作用。所有预防方案均观察到立即和持续的防龋作用。与氟化物清漆和糊剂的组合产生优异的额外防龋效果。
结论:作者得出结论,尽管随着时间的推移,所有方案都显示出针对根龋发展的即时和持续的防龋作用。氟化物清漆和PasteOne的组合产生了额外的防龋效果,这些效果一直很好,当组合添加PastePlus时,没有观察到额外的效果。作者认为,在研究的限制范围内,局部用氟化物清漆似乎对根面有长达8周的保护作用,并且该氟化物清漆应被视为预防老年人根面龋的重要辅助策略。