Fluoride Action Network

Enamel remineralization and surface roughness after treatment with herbal-containing toothpastes

Source: Journal of Clinical and Experimental Dentistry 13(9):e849-58. | October 5th, 2021 | Authors: Forcin LV, Oliveira TS, Tomaz PL, Matochek MH, et al.
Location: International
Industry type: Toothpaste

Background: Oral care products containing bioactive agents obtained from extracts of plant drugs were launched. This in vitro study investigated the effects of herbal-containing toothpastes associated or not with fluoride to remineralize the enamel after cariogenic challenge with pH cycling. The chemical and physical factors of toothpastes and the enamel surface roughness after brushing were also analyzed.

Material and methods: Sixty bovine enamel blocks were obtained and divided into 3 thirds: intact (untreated), demineralized (artificial caries lesion), and treated (caries lesion, pH cycling, and brushing with toothpastes). Toothpastes containing herbal compounds contained no fluoride [Galla chinensis (GCH)], low-F concentration [D’Or (DOR); Herbal Bliss (HBL)], or a different fluoride type [Elmex Anticaries (EAC)]. The results were compared to NaF-containing toothpastes: 1450 and 5000 ppm. Enamel blocks were brushed with the toothpastes using a pH-cycling model (7 days). The Knoop hardness (25g/10s) of the surface and the longitudinal sections were then evaluated. The percentage of surface hardness recovery (%SHR) was calculated. The enamel surface roughness, pH, particle size, zeta potential, and polydispersity index of toothpaste slurries were also evaluated. Data were statistically analyzed (a=5%).

Results: No significance was observed when %SHR was compared (p>0.05). DOR, GCH, and HBL were more effective in remineralizing the enamel subsurface. Significantly higher surface roughness was observed when treated with EAC and GCH (p<0.05).

Conclusions: All toothpastes were able to remineralize the enamel, especially the subsurface, with results equal or better than that of standard toothpastes.

Key words: Enamel, hardness, roughness, toothpaste, tooth remineralization.

* Full-text article online at http://fluoridealert.org/wp-content/uploads/forcin-2021.ocr_.pdf
* Abstract online at https://pubmed.ncbi.nlm.nih.gov/34603613/


Systematic reviews focusing on caries prevention in both permanent and deciduous teeth demonstrated that a toothpaste should contain as a minimum of 1,000 ?g F/g in order to provide a significant anticaries effect (1). For this reason, biomimetic remineralization, an alternative restorative, a methodology that imitates the natural process of mineralization have been developed to boost enamel remineralization (2). Thus, the mineral gain is facilitated by the addition of different boosters or supplements, even when associated with fluoride in low-F applications (3). In this way, several oral-care products have been launched with varied content of different active ingredients and claims promising protection for
teeth against enamel demineralization (4). The research on the development of new oral care products aims not only to reduce enamel demineralization and enhance the remineralizing actions of oral care formulations, but also minimizing the adverse side effects of conventional fluoride therapies (5). Despite these improvements, the action of fluoride in remineralization is still considered the gold standard when compared to other remineralization systems (6).

Fluoride toothpastes are claimed to prevent tooth decay by reducing the solubility of the enamel and promoting the remineralization of incipient lesions in comparison to non-fluoride toothpaste (7). In addition, systematic brushing with a fluoride toothpaste is the main non-professional intervention to prevent caries, but the caries-preventive effect varies as a function of different fluoride concentrations in the composition of the products: higher fluoride concentrations were found to positively correlate with increased remineralization effect and caries control (8).

Recently, oral care products containing bioactive agents obtained from extracts of plant drugs were launched (9). Most of herbal products claim to present actions on gingivitis, anti-plaque prevention, or for reducing dentin hypersensitivity (10). Conversely, a few studies have focused on the remineralization effects of toothpastes containing herbal additives in the composition. This invitro study aimed to investigate the remineralization  potential of various commercial toothpastes that contain extracts from vegetal drugs and active remineralization components different from that of standard NaF-containing toothpastes. The present study also evaluated the chemical and physical factors of the toothpaste slurries, and the consequences to the enamel surface roughness after brushing associated with the cariogenic challenge of pH cycling. The research hypotheses were: I- the toothpastes containing extracts from vegetal drugs and other active remineralization components will produce a higher remineralization potential of the enamel surface relative to the standard NaF-containing toothpastes; II- the enamel subsurface will be more effectively remineralized when treated with the herbal-containing toothpastes compared to conventional fluoride containing toothpastes; III- the enamel roughness will be greater after treatment with the toothpastes containing extracts from vegetal drugs and other active remineralization components.

* Full-text article online at http://fluoridealert.org/wp-content/uploads/forcin-2021.pdf