Browsing by Subject "dentifrices"

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    Fluoride dose-response of human and bovine enamel caries lesions under remineralizing conditions
    (2012-08) Lippert, Frank; Hara, Anderson T.; Department of Cariology, Operative Dentistry and Dental Public Health, School of Dentistry
    Purpose: To investigate the relative fluoride dose-response of human and bovine enamel caries lesions under remineralizing conditions and utilizing an established pH cycling model. Methods: Early caries-like lesions were formed in human and bovine enamel, characterized using Vickers surface microhardness (VHN) and assigned to five dentifrice treatment groups: 0/250/1100 ppm fluoride as sodium fluoride (F as NaF) formulation 1; 1100 ppm F as NaF formulation 2; 1000 ppm F as monofluorophosphate (MFP) formulation 3. The daily pH cycling regimen comprised: 4xl-minute dentifrice slurry treatments; lx4-hour acid challenge and intermittent remineralization in a l:l-mixture of pooled human/ artificial saliva. After 20 days, VHN of specimens were measured again and changes from lesion baseline calculated (REM). Subsequently, enamel fluoride uptake (EFU) was determined using the microdrill technique and specimens were demineralized again to determine their acid resistance (DEM). Data were analyzed using two-way ANOVA (factors: enamel, dentifrice). Results: Both enamel type and dentifrice as well as their interaction affected REM and DEM. EFU was only affected by dentifrice. Human and bovine enamel showed a good fluoride dose-response for REM and correlated well. However, bovine enamel showed more remineralization than human enamel. There were good correlations between dentifrice-F concentration vs. REM and EFU, and between REM vs. EFU, regardless of enamel type.
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    In situ anticaries efficacy of dentifrices with different formulations – A pooled analysis of results from three randomized clinical trials
    (Elsevier, 2018-10) Zero, Domenick T.; Lippert, Frank; Hara, Anderson T.; Creeth, Johnathan; Newby, Evelyn; Butler, Andrew; Constantin, Paul; Bosma, Mary Lynn; Cariology, Operative Dentistry and Dental Public Health, School of Dentistry
    Objectives Data generated from three similar in situ caries crossover studies presented the opportunity to conduct a pooled analysis to investigate how dentifrice formulations with different fluoride salts and combinations at concentrations of 1400–1450 ppm F, different abrasive systems and in some cases, carbomer (Carb), affect enamel caries lesion remineralization and fluoridation. Methods Subjects continuously wore modified partial dentures holding two gauze-covered partially-demineralized human enamel specimens for 14 days and brushed 2×/day with their assigned dentifrice: Study 1: sodium fluoride (NaF)/Carb/silica, NaF/silica, NaF + monofluorophosphate (MFP)/chalk; Study 2: NaF/Carb/silica, NaF + MFP/dical, amine fluoride (AmF)/silica; Study 3: NaF/Carb/silica, NaF + stannous fluoride (SnF2)/silica/hexametaphosphate (HMP). All studies included Placebo (0 ppm F) and/or dose-response controls (675 ppm F as NaF [675F-NaF]) ±Carb. Specimens were evaluated for percentage surface microhardness recovery (SMHR) and enamel fluoride uptake (EFU). Results All 1400–1450 ppm F dentifrices except NaF + SnF2/silica/HMP provided significantly greater lesion remineralization than Placebo (p < 0.0001): differences in SMHR ranged from 17.46% (NaF + MFP/dical) to 26.66% (AmF/silica). For EFU (back-transformed log EFU), all 1400–1450 ppm F dentifrices gave significant fluoride uptake compared to Placebo (p < 0.0001): increases in EFU ranged from 4.95 μg F/cm2 (NaF + SnF2/silica/HMP) to 16.32 μg F/cm2 (NaF/carb/silica). Dentifrices containing NaF or AmF as sole fluoride source provided the greatest remineralization and fluoridation; Carb addition did not alter fluoride efficacy; some excipients appeared to interfere with the cariostatic action of fluoride. Treatments were generally well-tolerated with ≤4 treatment-related adverse events per study. Conclusion Commercially available fluoride dentifrices varied greatly in their ability to remineralize and fluoridate early caries lesions. Clinical significance Fluoride dentifrices are the most impactful anticaries modality worldwide. While clinical caries trials have not consistently shown the superiority of one formulation over another, these findings using a sensitive in situ caries model indicated that dentifrices containing NaF or AmF as the sole fluoride source provided the greatest remineralization and fluoridation benefits.