Whitening efficacy of popular natural products on dental enamel

Abstract

The objective of this study was to evaluate the effect of natural bleaching products on the color, whiteness, and superficial properties of dental enamel. Seventy fragments of bovine teeth were obtained (6mm x 6mm x 2mm). Initial surface roughness (Surfcorder SE1700, Kosakalab), microhardness (HMV-2, Shimadzu), color (EasyShade, VITA), and surface gloss (Micro-Gloss 45º BYK, Gardner) readings were done. Samples were separated into five groups (n=14) according to the treatments used: CT-conventional toothpaste (negative control); CH-charcoal; TU-turmeric; BP-banana peel, and CP16%-16% carbamide peroxide gel (positive control, 4 h/day for 14 days), and then brushed for 560 cycles (T1) and 1200 cycles (T2), equivalent to 14 and 30 days of brushing. New measurements were performed after T1 and T2. The whiteness index for dentistry change (∆WID) and Weight loss (Wl) were calculated. CP16% demonstrated the highest (p<.05) color change (ΔE00) and ∆WID (2-way ANOVA, Bonferroni, p<.05). Surface gloss alterations were lower for TU, CP16%, and BP. CT and CH increased surface roughness (p<.05). CP16% decreased enamel microhardness. CH presented medium abrasiveness, and CT and TU, low abrasiveness. The popular bleaching products were not efficient for tooth whitening. Furthermore, brushing with charcoal increased the enamel surface roughness, and CP16% decreased enamel microhardness over time

Remineralization, color stability and surface roughness of tooth enamel brushed with activated charcoal‐based products

“…Color changes were probably due to increased surface roughness. As mentioned before, abrasive particles in oral hygiene products can increase the surface roughness, 6 which can alter the light reflection, and consequently, the tooth color 18 …”

“…Regarding the color stability, the second hypothesis was rejected since the ACPs caused tooth color alteration similar to Control group, except for Charcoal powder that showed difference. Charcoal powder is insoluble in water, so it is difficult to spread out while brushing 18 . In addition, it does not have enough thixotropy to remain in contact with the enamel surface.…”

“…Charcoal powder is insoluble in water, so it is difficult to spread out while brushing. 18 In addition, it does not have enough thixotropy to remain in contact with the enamel surface. Thus, probably Charcoal powder is less efficient than ACTs, resulting in less color change.…”

“…For toothbrushing with activated charcoal powder, a paste was prepared by mixing 1.5 g of charcoal powder with 2 mL of distilled water per sample 18 . The paste (1 g) was dispensed on each sample, and the brushing was performed as mentioned before.…”

In vitro assessment of activated charcoal‐based dental products

“…where when natural products were tested on color change compared with carbamide peroxide. 18 The whitening mechanism of activated charcoal-based dentifrices is based on the adsorption capacity of pigments, which removes pigments, chromophores, or extrinsic stains responsible for the natural color alteration of teeth. Previous study reported that charcoal-based dentifrices demonstrated a whitening effect on enamel after extrinsic staining with black tea, 6 this effect was also observed in the present study, when analyzing the values of ΔE 00 .…”