Toothpaste cannot mitigate dental erosion and dentin hypersensitivity problems, finds a new study. Existence of many brands of toothpaste in the market promise to reduce the rising prevalence of dental erosion and dentin hypersensitivity but it is found to be a failure. The findings of the study are published in the journal Scientific Reports.
However, the study conducted at the University of Bern in Switzerland with the participation of a scientist supported by a scholarship from the Sćo Paulo Research Foundation - FAPESP showed that none of the nine analyzed toothpastes was capable of mitigating enamel surface loss, a key factor in tooth erosion and dentin hypersensitivity.
"Research has shown that dentin must be exposed with open tubules in order for there to be hypersensitivity, and erosion is one of the causes of dentin exposure. This is why, in our study, we analyzed toothpastes that claim to be anti-erosive and/or desensitizing," said Samira Helena Joćo-Souza, a PhD scholar at the University of Sćo Paulo's School of Dentistry (FO-USP) in Brazil and first author of the article.
The authors of the study stressed that these toothpastes perform a function but that they should be used as a complement, not as a treatment, strictly speaking. According to Joćo-Souza, at least three factors are required: treatment prescribed by a dentist, use of an appropriate toothpaste , and a change in lifestyle, especially diet.
"Dental erosion is multifactorial. It has to do with brushing, and above all, with diet. Food and drink are increasingly acidic as a result of industrial processing", she said.
The scientist highlights that dental erosion is a chronic loss of dental hard tissue caused by acid without bacterial involvement - unlike caries, which is bacteria-related. When it is associated with mechanical action, such as brushing, it results in erosive wear. In these situations, patients typically experience discomfort when they drink or eat something cold, hot or sweet.
"They come to the clinic with the complaint that they have caries, but actually, the problem is caused by dentin exposure due to improper brushing with [a] very abrasive toothpaste, for example, combined with frequent consumption of large amounts of acidic foods and beverages," said Professor Ana Cecķlia Corrźa Aranha, Joćo-Souza's supervisor and a co-author of the article.
In our clinical work, we see patients with this problem in the cervical region between [the] gum and tooth. The enamel in this region is thinner and more susceptible to the problem," she added.
The scientists tested eight anti-erosive and/or desensitizing toothpastes and one control toothpaste, all of which are available from pharmacies and drugstores in Brazil or Europe.
The research simulated the effect of brushing once a day with exposure to an acid solution for five consecutive days on tooth enamel. The study used human premolars donated for scientific research purposes, artificial saliva, and an automatic brushing machine.
"We used a microhardness test to calculate enamel loss due to brushing with the toothpastes tested. The chemical analysis consisted of measuring toothpaste pH and levels of tin, calcium, phosphate and fluoride," Joćo-Souza explained.
The physical analysis consisted of weighing the abrasive particles contained in the toothpastes, measuring their size, and testing wettability - the ease with which toothpaste mixed with artificial saliva could be spread on the tooth surface.
"During brushing with these toothpastes mixed with artificial saliva, we found that the properties of the toothpastes were different, so we decided to broaden the scope of the analysis to include chemical and physical factors. This [broadening] made the study more comprehensive," Joćo-Souza said.
All of the analyzed toothpastes caused progressive tooth surface loss in the five-day period. "None of them was better than the others. Indication will depend on each case. The test showed that some [toothpastes] caused less surface loss than others, but they all resembled the control toothpaste [for] this criterion. Statistically, they were all similar, although numerically, there were differences," Aranha said.
"We're now working on other studies relating to dentin in order to think about possibilities, given that none of these toothpastes was found capable of preventing dental erosion or dentin hypersensitivity, which is a cause of concern."
The scientists plan to begin a more specific in vivo study that will also include pain evaluations.