Dental erosion has a multifactorial etiology with contributions from chemical, biological and behavioral factors. In terms of chemical factors, type of foods and drinks is important. The chemical factors that determine whether foods and drinks are erosive are low pH, type of acid, meaning a low acid dissociation constant (pKa), high buffer capacity and low mineral content. However, little is known about the combination of these chemical factors in sour sweets and drinks found on the Norwegian market. Therefore, the purpose of this study was to investigate the erosion promoting and -inhibiting chemical properties of selected products.

The products (n = 24) were divided into groups: candy/pastilles, chewing gum and drinks. The acidity (pH) and buffer capacity (titratable acidity, TA) was measured. In addition, the mineral content of phosphate, fluoride and calcium ions was analyzed in six products. The type of acid was found from the lists of ingredients of the products. Eighteen of 22 products had pH values below 4.5; which is the critical limit for dissolution of the enamel due to erosion. The TA values varied within and between the groups. In one-third of the analyzed products, the TA values were above the average of the products studied. Most products contained citric acid, which is a relatively low acid dissociation constant. On average they had a higher TA than products containing other acids. One of the six products (smoothie) had 150 times higher concentrations of phosphate than the others, which had values at the limit of detection. One pastille and one lozenge product had up to 600 times higher concentrations of calcium and fluoride ions, respectively, compared to the other products. However, all mineral concentrations were lower than the concentrations required to counteract enamel erosions.

In addition to consistently low pH values, the investigated sour sweets and drinks had high TA and low concentrations of minerals. This combination of chemical properties of a food or drink can promote the development of dental erosions.

Reference
Erosjonsfremmende egenskaper hos sure søtsaker og drikker
Stenhagen, ISR, Singh A, Vitija E, Stenhagen KR, Bruzell E, Mulic A.
Nor Tannlegeforen Tid. 2019; 129: 876-82