Artificial Enamel Carious Lesions Research Articles

In Vitro Evaluation of the Effect of Fluoride Varnish Application Frequency on Initial Enamel Lesions

Purpose: The aim of this study is the in vitro evaluation of the effect of fluoride varnish application at different frequencies on initial enamel lesions by surface microhardness (SMH) measurements. Material and Methods: This in vitro experimental study was performed on 80 extracted unerupted third molar teeth. The teeth were divided randomly into 4 groups: Group 1: Fluoride varnish application once a year, Group 2: Fluoride varnish application 4 times at 1 week intervals, Group 3: Fluoride varnish application 4 times a year with an interval of 3 months, Group 4: Application of fluoride varnish twice a year at 6-month intervals. Artificial enamel carious lesions were created by inserting the specimens in demineralization solution for 96 hours. The Vicker’s microhardness number (VHN) was measured at baseline, after demineralization and after fluor varnish application and 1 year after fluoride treatments of each group. The percent change in surface microhardness (% SMH change) was also calculated. Anova and Kruskall-Wallis H test, t-test and/or Wilcoxen sign test were used with 95% confidence levels to compare differences. Results: The surface microhardness values and recovery of surface hardness values of the groups were found as follows: Group 3> Group 2>Group 4> Group 1. VHN of Group 3 was statistically significantly higher than other groups (p<0.05). Conclusion: Fluoride varnish application 4 times a year with an interval of 3 months showed significantly higher enamel SMH than that of the other groups (p<0.05).

Fluoridated milk enhances the mineral density of artificial proximal carious lesions in situ

Objective To compare the mineral density (MD) of non-fluoridated-milk (non-F-milk), fluoridated-milk (F-milk), adjunctive to 1000-ppm-fluoride dentifrice (FD), and 1000-ppm-FD alone of proximal artificial enamel carious lesions (AECL) in high caries-risk patients. Materials and methods This double-blind, cross-over in situ study comprised seven high caries-risk volunteers. Orthodontic brackets with one slab of AECL were fixed randomly to each volunteer per phase. The study comprised three experimental periods with a 7-d wash-out period using FD between sessions; (1) A four-week tooth brushing with FD 2×/day by all subjects as a control. The participants were then randomly allocated to (2) drinking 2.5-ppm-F-milk 1×/day or (3) non-F-milk 1×/day, adjunctive to tooth-brushing with FD for 4-weeks. The subjects crossed over from each type of milk and continued the same protocol for another four weeks. After each phase, the MD of each specimen was analyzed using micro-computed tomography (Micro-CT). Results The baseline MD was not significantly differences (p = .653). When brushing with FD and drinking F-milk, the MD gain was significantly higher (11.68 ± 2.89%) compared with brushing with FD and drinking non-F-milk (4.59 ± 1.78%) (p = .003) or brushing with FD alone (5.30 ± 2.10%) (p = .003). Conclusions F-milk adjunctive to FD significantly increased MD gain compared with non-F-milk + FD or FD alone.

PERBEDAAN KEKERASAN PERMUKAAN ENAMEL SETELAH APLIKASI FLUORIDE VARNISH DAN CASEIN PHOSPO PEPTIDE-AMORPHOUS CALSIUM PHOSPHATE FLUORIDE (CPP-ACPF) (PENELITIAN IN VITRO)

Background: Caries is a chronic, slowly progressing disease, with symptoms not detected at the onset of the disease but generally much later. Its initiation is associated with demineralization (calcium and phosphate loss) of subsurface tooth enamel, resulting in the formation of a subsurface lesion. To restore the natural equilibrium, either remineralization must be enhanced or demineralization must be retarded. There are some topical agents that can enhance remineralization such as topical fluor and casein phosphopeptide – amorphous calcium phosphate (CPP-ACP). Purpose: The aim of this study is to analyze the differences of the enamel surface microhardness after application of fluoride varnish and CPP-ACPF. Methode: 27 blocks bovine enamel were devided into 3 groups. Group 1 – control (No surface treatment), group 2 – fluoride varnish and group 3 – CPP-ACPF. Initial surface hardness enamel was measured for all enamel specimens. Artificial enamel carious lesions were created by immersing enamel samples to demineralization solution (pH 4,5) for 72 hours at temperature 370 C. The surface microhardness of demineralized enamel specimens was measured. A caries progression test (pH cycling) was carried out, which consisted of alternative demineralization (3 hours), remineralization with artificial saliva (21 hours) and application topical agent twice a day for 14 days. Then, the last surface enamel microhardness is measured. Result: Group 3 showed significantly highest Vickers hardness number (P<0,05) followed by group 2 and the lowest is group 1. Conclusions: This study proved that enamel surface microhardness after application of CPP-ACPF was higher than fluoride varnish.

Remineralization Potential of Calcium and Phosphate-based Agents and Their Effects on Bonding of Orthodontic Brackets.

To compare the remineralization potential of Clinpro Tooth Crème (CTC C, 3M Oral Care) containing functionalized tricalcium phosphate (fTCP), Tooth Mousse (TM, GC) containing casein phosphopeptide amorphous calcium phosphate (CPP-ACP), and Tooth Mousse Plus (TMP, GC) containing casein phosphopeptide amorphous calcium phosphate with fluoride (CPP-ACPF) and their effects on the shear bond strength (SBS) of orthodontic brackets to enamel. In Part I of the study, 51 premolars were divided into 3 groups: 1: fTCP; 2: CPP-ACP; 3: CPP-ACPF. Artificial carious lesions were created and immersed in remineralizing solution for 30 days. Specimens were evaluated using Knoop microhardness and transverse microradiography. The percentage of surface hardness recovery (%SHR), change in lesion depth (∆LD), and mineral loss (∆∆Z) were analyzed using one-way ANOVA. In Part II of the study, 80 premolars were divided into 5 groups: A: brackets bonded to sound enamel; B: brackets bonded to demineralized enamel (DE); C-E: demineralized enamel immersed in remineralizing solution containing fTCP (group C), CPP-ACP (group D), or CPP-ACPF (group E) before bracket bonding. The SBS of half of the specimens were tested immediately, while the other half were tested after thermocycling. Data were analyzed using two-way ANOVA. TMP showed significantly higher %SHR, ∆LD and ∆∆Z compared to the other groups (p < 0.05). Both control and TMP had the highest SBSs and demineralized enamel the lowest, irrespective of thermocycling. No significant difference in SBS was found between TM and TMP after thermocycling. Tooth Mousse Plus achieved significant remineralization of artificial enamel carious lesions without adverse effect on shear bond strength of orthodontic brackets to remineralized enamel.

Arginine promotes fluoride uptake into artificial carious lesionsin vitro

This study focused on the interaction of arginine and fluoride on the remineralization of artificial enamel carious lesions in vitro. Human enamel blocks with artificial carious lesions were prepared and randomly divided into six treatment groups (n=30 for each group): deionized water, arginine solution, NaF solution, arginine/NaF solution, arginine-free fluoride toothpaste slurry and arginine-containing fluoride toothpaste slurry. After a pH-cycling regimen for 10 days, subsets of specimens from each group were subjected to independent analysis, including surface microhardness (n=8/30), cross-sectional microhardness (n=8/30), enamel fluoride uptake (n=8/30) and polarized light microscopy (n=6/30). The samples tested for surface microhardness were further subjected to simulated plaque acid challenge before surface microhardness was remeasured. Arginine solution promoted remineralization compared with deionized water control (p<0.05). When used in combination with fluoride, arginine significantly increased fluoride uptake compared with fluoride alone (p<0.05). In addition, lesions treated with arginine-containing toothpaste also showed superior fluoride uptake compared with those treated with conventional fluoride toothpaste (p<0.05). Arginine promoted enamel fluoride uptake when used in combination with fluoride, thereby contributing to resistance of enamel to carious demineralization.

Remineralization of initial enamel carious lesions using fluoridated milk in vitro

Objectives. Milk is a universal dietary component and it is now recognized as an effective medium for the delivery of fluoride (F). This study sought (i) to evaluate fluoridated milk (2.5 ppm, 5 ppm, 10 ppm) for remineralizing carious lesions and (ii) to determine the optimum frequency for treating carious lesions with fluoridated milk. Materials and methods. Artificial carious lesions, 90–180 μm deep, were created on extracted third molar teeth that were sectioned to produce specimens of 100–120 μm thickness. Specimens were randomly divided into 13 groups (n = 20) for treatment with deionized water, plain milk or fluoridated milk (2.5 ppm, 5 ppm, 10 ppm); once daily, twice daily or on alternate days as part of a 20-day pH cycling model. Lesion depth (LD) and mineral content were evaluated before and after pH cycling. Paired t-test, ANOVA and Student-Newman-Keuls tests were employed to make comparisons within and between the different groups. Results. Fluoridated milk significantly reduced LD and increased the mineral content of the lesions compared to plain milk and deionized water (p < 0.05). The greatest reduction in LD was with 2.5 ppm F milk used twice daily (p < 0.05). Conclusions. Milk with 2.5 ppm F used twice daily demonstrated the greatest remineralization of artificial enamel carious lesions in vitro.

Remineralization potential of bioactive glass and casein phosphopeptide-amorphous calcium phosphate on initial carious lesion: An in-vitro pH-cycling study

Aims:The aim of this study was to evaluate and compare the remineralization potential of bioactive-Glass (BAG) (Novamin®/Calcium-sodium-phosphosilicate) and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) containing dentifrice.Materials and Methods:A total of 30 sound human premolars were decoronated, coated with nail varnish except for a 4 mm × 4 mm window on the buccal surface of crown and were randomly divided in two groups (n = 15). Group A — BAG dentifrice and Group B — CPP-ACP dentifrice. The baseline surface microhardness (SMH) was measured for all the specimens using the vickers microhardness testing machine. Artificial enamel carious lesions were created by inserting the specimens in de-mineralizing solution for 96 h. SMH of demineralized specimens was evaluated. 10 days of pH-cycling regimen was carried out. SMH of remineralized specimens was evaluated.Statistical Analysis:Data was analyzed using ANOVA and multiple comparisons within groups was done using Bonferroni method (post-hoc tests) to detect significant differences at P < 0.05 levels.Results:Group A showed significantly higher values (P < 0.05) when compared with the hardness values of Group B.Conclusions:Within the limits; the present study concluded that; both BAG and CPP-ACP are effective in remineralizing early enamel caries. Application of BAG more effectively remineralized the carious lesion when compared with CPP-ACP.

Effects of fluoridated milk on artificial enamel carious lesions: A pH cycling study

ObjectiveTo investigate the relationship between concentration of fluoride in milk and its re-mineralizing efficacy, and to test whether increasing the volume of fluoridated milk has any effect on its re-mineralizing efficacy. MethodsThird molars were painted leaving a 1mm window on the buccal and/or lingual surfaces. Artificial carious lesions were induced using a de-mineralizing solution. The teeth were then sectioned longitudinally. Specimens were randomly assigned to 15 groups according to different concentrations and volume; i.e. 2.5ppm, 5ppm, 7.5ppm, 10ppm, 15ppm, 20ppm, and 250ppm of fluoride with 25ml/section and 50ml/section. De-ionized water and plain milk were used as controls. Sections were subjected to pH cycling for 20 days. Polarized light microscopy and micro-radiography were utilized to record the lesion characteristics before and after pH cycling. ResultsMean lesion depths decreased significantly in all the fluoride groups, and increased significantly in the control groups. There were no differences in percentage of lesion depth decrease when the volume was doubled for the same fluoride concentration. There were also no statistically significant differences between percentages of decrease in lesion depth when the concentration of fluoride in milk was increased. ConclusionFluoridated milk demonstrated a remineralization efficacy on early enamel carious lesions. A 2.5ppm fluoride milk concentration provided similar remineralization potential to that of higher fluoride concentration in milk.

Remineralization potential of fluoride and amorphous calcium phosphate-casein phospho peptide on enamel lesions: Anin vitrocomparative evaluation

Aim:This in vitro study was conducted on enamel blocks of human premolars with the aim of evaluating the remineralization potential of fluoride and ACP-CPP and the combination of ACP-CPP and fluoride on early enamel lesions.Materials and Methods:Fifteen intact carious free human premolars were selected. The coronal part of each tooth was sectioned into four parts to make 4 enamel blocks. The baseline SMH (surface microhardness) was measured for all the enamel specimens using Vickers microhardness (VHN) testing machine. Artificial enamel carious lesions were created by inserting the specimens in demineralization solution for 3 consecutive days. The SMH of the demineralised specimens was evaluated. Then the four enamel sections of each tooth were subjected to various surface treatments, i.e. Group 1- Fluoride varnish, Group 2- ACP-CPP cream, Group 3- Fluoride + ACP-CPP & Group 4- Control (No surface treatment). A caries progression test (pH cycling) was carried out, which consisted of alternative demineralization (3hours) and remineralization with artificial saliva (21 hours) for five consecutive days. After pH cycling again SMH of each specimen was assessed to evaluate the remineralization potential of each surface treatment agent. Then, to asses the remineralization potential of various surface treatments at the subsurface level, each enamel specimen was longitudinally sectioned through the centre to expose the subsurface enamel area. Cross-sectional microhardness (CSMH) was evaluated to assess any subsurface remineralizationResults:Statistical analysis using one-way ANOVA followed by multiple comparisons test was applied to detect significant differences at P ≤ 0.05 levels between various surface treatments at different phases.Conclusions:With in the limits, the present study concludes that; ACP-CPP cream is effective, but to a lesser extent than fluoride in remineralizing early enamel caries at surface level. Combination of fluoride and ACP-CPP does not provide any additive remineralization potential compared to fluoride alone. Fluoride, ACP-CPP and their combination are not effective in remineralizing the early enamel caries at the subsurface level.

Oral Session O04/Cariology 4

Introduction Milk is an universal dietary component that could be an effective medium for the delivery of fluoride. The objective of this study was to determine whether the frequency of treating artificial carious lesions with fluoridated milk of different concentrations alters the re-mineralizing potential. Materials and Methods Artificial carious lesions, (90-180孠deep), were formed on the buccal and lingual enamel surfaces of extracted molars using a de-mineralizing solution. The teeth were sectioned to create specimens 100-150孠thick. The sections were painted with a varnish except for the outer surface of the lesion. The specimens were randomly divided into thirteen groups and treated with: water, plain milk or fluoridated milk (2.5ppm, 5ppm, 10ppm) once, twice or on alternate days using a 20-day pH cycling model. Lesion depth and mineral content (Vmax) before and after the pH cycle were evaluated using polarized light microscopy and microradiography. Paired t-test, ANOVA and Student-Newman-Keuls tests were employed to make comparisons within each group and between the different groups. Results Fluoridated milk (2.5ppm, 5ppm, 10ppm) significantly reduced the lesion depth and increased the Vmax of the lesions in comparison to the control groups (p<0.05). Specimens treated with 2.5ppm fluoride milk twice daily exhibited the greatest reduction in lesion depth (p<0.05). Conclusion Fluoridated milk has a beneficial effect on the progression of artificial enamel carious lesions. Milk with 2.5ppm fluoride, when used twice daily, exhibited a greater re-mineralizing potential than when used once daily, or on alternate days with the same or higher concentrations.