Remineralization and repair of enamel surface by biomimetic Zn-carbonate hydroxyapatite containing toothpaste: a comparative in vivo study

Abstract

Consumption of acidic foods and drinks and other factors that cause enamel wear are responsible for the daily enamel loss and degradation. Use of some toothpastes that have been showed to possess different properties of remineralisation and/or repair of the enamel surface may help to protect tooth enamel. The aim of this study was to evaluate whether the use of toothpaste containing Zn-carbonate hydroxyapatite (CHA) nanostructured microcrystals may exert remineralization/repair effects of the enamel surface. Two groups of patients, aged between 18 and 75 years, used a Zn-CHA nanocrystals-based toothpaste (experimental group) and a potassium nitrate/sodium fluoride toothpaste (active control group) for 8 weeks. At the end of this period, extractions were performed in five subjects per study group. Negative controls consisted of two subjects treated with non-specified fluoride toothpaste. Teeth were processed for morphological and chemical-physic superficial characterizations by means of Scanning Electronic Microscopy with Elementary analysis, X-Ray Diffraction analysis and Infrared analysis. In this study, the use of a Zn-CHA nanocrystals toothpaste led to a remineralization/repair of the enamel surface, by deposition of a hydroxyapatite-rich coating. On the other hand, the use of both a nitrate potassium/sodium fluoride and non-specified fluoride toothpastes did not appreciably change the enamel surface. In conclusion, this study demonstrates that the toothpaste containing Zn-CHA nanostructured microcrystals, differently from nitrate potassium/sodium fluoride and non-specified fluoride toothpastes, may promote enamel superficial repair by means of the formation of a protective biomimetic CHA coating.

Nano/micro fluorhydroxyapatite crystal pastes in the treatment of dentin hypersensitivity: an in vitro study

“…The same zinc-(CHA) nanocrystals was able to coat enamel surfaces with the potential for repair and remineralization [39]. Unfortunately, the results in the aforementioned study were qualitative which precludes comparison with our results.…”

In Vivo Effects of a Hydroxyapatite-Based Oral Care Gel on the Calcium and Phosphorus Levels of Dental Plaque

“…This is in line with studies showing the interaction of HAP particles with enamel surfaces. [14][15][16] For example, Kensche et al found an accumulation of HAP particles into the pellicle after using a HAP-based mouthwash in a transmission electron microscopic (TEM) study. 30 The interaction may be based on mineral bridges between HAP particles and enamel surfaces as shown by Fabritius-Vilpoux et al in a scanning electron microscopy (SEM) study.…”

“…13 HAP particles interact with enamel surfaces as shown in vitro, 14 in situ, 15 and in vivo. 16,17 Clinical studies have shown effects of HAP-based toothpastes, for example, in prevention of enamel caries 17 and reducing dentin hypersensitivity, 18 as well as in improving periodontal health. 19 Additionally, HAP particles reduce bacterial colonization to enamel surfaces in situ similar to chlorhexidine without having antibacterial effects, but showing antiadherent properties.…”

“…19 Additionally, HAP particles reduce bacterial colonization to enamel surfaces in situ similar to chlorhexidine without having antibacterial effects, but showing antiadherent properties. 15 HAP for oral care applications may differ in composition (e.g., substitutions of foreign ions for calcium like zinc 16 ), as well as in crystallite morphology, and crystallite size. 10 A recently published review article describes the multifunctionality of HAP and its modes of action in preventive oral health care.…”

Biomimetic Effect of Nano-Hydroxyapatite in Demineralized Enamel before Orthodontic Bonding of Brackets and Attachments: Visual, Adhesion Strength, and Hardness in In Vitro Tests

“…ese aggregates present a nanostructured surface area of about 80 m 2 /g. ese crystals have been reported to be used in toothpastes and mouthwashes as mineralized agents [30]. e consistency of nano-hydroxyapatite solution is not toothpaste-like, but it is a solid mousse material to be applied on tooth surfaces following normal brushing.…”