Prevention of Caries and Dental Erosion by Fluorides-A Critical Discussion Based on Physico-Chemical Data and Principles.

Matthias Epple,Frederic Meyer,Joachim Enax

doi:10.3390/dj10010006

Matthias Epple, Frederic Meyer + Show 1 more

Open Access

https://doi.org/10.3390/dj10010006

Copy DOI

Abstract

Dental erosion is a common problem in dentistry. It is defined as the loss of tooth mineral by the attack of acids that do not result from caries. From a physico-chemical point of view, the nature of the corroding acids only plays a minor role. A protective effect of fluorides, to prevent caries and dental erosion, is frequently claimed in the literature. The proposed modes of action of fluorides include, for example, the formation of an acid-resistant fluoride-rich surface layer and a fluoride-induced surface hardening of the tooth surface. We performed a comprehensive literature study on the available data on the interaction between fluoride and tooth surfaces (e.g., by toothpastes or mouthwashes). These data are discussed in the light of general chemical considerations on fluoride incorporation and the acid solubility of teeth. The analytical techniques available to address this question are presented and discussed with respect to their capabilities. In summary, the amount of fluoride that is incorporated into teeth is very low (a few µg mm−2), and is unlikely to protect a tooth against an attack by acids, be it from acidic agents (erosion) or from acid-producing cariogenic bacteria.

Highlights

We discuss the physico-chemical aspects of acidic attack on teeth, both from acidic foods and beverages, and from acid-producing caries bacteria
We have focused on the action of fluoride, which has a well-established ability to prevent caries
NaF reduced the erosion by 19% compared with a fluoride-free control, whereas amine fluorides (AmF)/NaF/SnF2 reduced it by 67% [53]

Summary

Introduction

We discuss the physico-chemical aspects of acidic attack on teeth, both from acidic foods and beverages (dental erosion), and from acid-producing caries bacteria. The available literature was mainly analyzed for the analytical aspects of these effects, i.e., studies in which teeth were subjected to an acidic attack and further analyzed. The mineral content in enamel is very high (about 97 wt.%) to ensure its hardness. This hardness is due to the mineral content, and to the complex hierarchical arrangement of the hydroxyapatite needles in enamel [1,2,4]. The density of enamel is 2.6 to 2.8 g cm−3 [5], i.e., about 80–85% of crystalline hydroxyapatite (3.18 g cm−3 ), underscoring its high mineral content, and some degree of porosity

Methods

Findings

Discussion

Conclusion