The effectiveness of toothpaste use is affected by the oral hygiene habits and motivation of individuals. Societies with low socioeconomic and sociocultural levels have problems accessing oral hygiene materials such as toothpaste. Thus, oral and dental health is adversely affected.(“Fluorides and oral health. Report of a WHO Expert Committee on Oral Health Status and Fluoride Use.” 1994; Topaloglu-Ak et al. 2009). Oral health is essential for general health and complete well-being. Untreated pain, infection, and oral diseases reduce the quality of life and cause people to avoid education and productivity. Oral health is also essential for healthy aging. It plays a crucial role in nutrition, employability, self-confidence, and successful social communication (FDI World Dental Federation 2020). The main way to enhance oral health is through the use of toothpaste.
Many studies have been conducted on the factors affecting toothpaste selection, and it has been observed that the results of these studies are different from each other (Kote et al. 2013; Opeodu and Gbadebo 2017; Umanah and Braimoh 2017). This may be due to the different sociodemographic characteristics of the populations and races studied. Considering the historical development of toothpastes, oral care products have gained more importance with the increasing aesthetic concern and the development of health awareness. However, dozens of products in the markets can cause people who do not have much knowledge about the contents of oral care products to have difficulty in choosing. In addition, the wide range of products to be preferred makes the selection difficult. Personal, psychological, and sociodemographic factors of individuals play a significant role in the purchasing decision process and in determining which brand to choose (DERAKHSHİ 2017). Taking into account that individuals always pursue their own interests, their attitude towards reducing prices in their shopping strategies, and the effect of culture on individuals’ purchasing behavior, it may be thought that individuals are more likely to use the grocery store to procure toothpaste (DERAKHSHİ 2017; Tengilimoğlu 2012). The World Health Organization desires that a newly produced toothpaste should be affordable (Jones et al. 2005). From a cyclical point of view, the prices of toothpaste are high in our country, as in many developing countries. It is possible for individuals to prefer the markets when they buy toothpaste in terms of the possibility of not having the opportunity to make discounted shopping from pharmacies, and the opportunity to shop at affordable prices with the campaigns organized by the markets. Therefore, within the scope of this study, only the toothpastes available in the market aisles are included, and this is one of the limitations of the study. Toothpastes that are not included in the aisle can be obtained from abroad through online shopping sites. However, it is clear that not every individual can have this opportunity. For this reason, toothpastes that can be obtained online have not been included in this study in order to promote standardization.
Toothpastes can be produced to solve a specific problem for oral and dental health. Pastes are used to prevent caries, remove gum disease, remove stains on tooth surfaces, eliminate halitosis, etc. Various active ingredients are added to their structures. In addition to these main ingredients, various auxiliary components can be found in the toothpaste structure, such as sweetener, thickener, preservative, and detergent-like foam (Jenkins et al. 1991). However, some of these components that are included in the structure of the paste have the potential to cause side effects and damage the oral tissues and other cells or organs in the body, either systemically or locally. Components such as fluorine, sodium lauryl sulfate (SLS), paraben derivatives, titanium dioxide, and sodium saccharin are some of them (Lippert 2013; Tadin et al. 2019). In addition, with the acceleration of genetic studies in recent years, components such as arginine that have been found to have adverse metagenomic effects can also be included in this group (Carda-Diéguez et al. 2022). Although the concentration of these components in the paste is low, it should not be ignored that the levels of that may increase by taking it into the body through food, environment, and use of cosmetic products.
In this study, fluorine derivatives were detected in 137 of 161 different pastes on the market shelves in our country. It is seen that about 15% of toothpastes do not contain fluorine. From a global perspective, it is seen that only a small portion of the world's population has access to fluoride toothpaste, and it is stated that the benefits of fluoride toothpastes are not available in many middle and low-income countries due to high prices for poor and disadvantaged populations (“Fluorides and oral health. Report of a WHO Expert Committee on Oral Health Status and Fluoride Use.” 1994; Gkekas et al. 2022). It is seen that the prevalence of oral diseases, especially dental caries, is soaring in Turkey due to the fact that the annual consumption of toothpaste (Akar 2014) and the number of toothbrushes per capita is lower than in developed countries, and the frequency of going to the dentist in certain age groups is lower than it should be (Gokalp et al. 2007; Gokalp and Guciz Dogan 2009). The way to reverse this situation is through the use of fluoride toothpaste and its various public health and health policies (tax reduction, price equalization, competition, supporting local production) (Gkekas et al. 2022). The addition of fluoride to toothpastes is considered essential for daily oral care, and it is stated that this is a gold standard (Hitz Lindenmüller and Lambrecht 2011; Walsh et al. 2010). According to the analysis, the use of fluoridated toothpaste is much more effective in preventing dental caries than the use of non-fluoridated toothpaste (Walsh et al. 2010). It has been accepted that toothpastes containing fluoride in the range of 1000-1500 ppm are sufficient in terms of anti-caries and preventing fluoride toxicity. The number of studies on fluorine awareness in our country is limited (Ak et al. 2018; Ucuncu et al. 2022). In one study, about 35% of 431 participants stated that they did not have enough information about flourine. While 29.2% of them thought that it was both beneficial and harmful, 12.3% of them stated that it was harmful (Ucuncu et al. 2022). In another study, similar results were found, and it was shown that increasing the level of education decreased the tendency towards fluoridated toothpastes and the affinity for various gel applications (Ak et al. 2018). Although there are many debates about whether there is fluorine in toothpastes today, especially in Turkey, it is known that fluoride does not harm the body systemically when it is kept in optimal doses. High-dose ingestion at one time may cause acute fluoride toxicity (Küçükeşmen and Sönmez 2008). High levels of fluoride intake can cause dental fluorosis and systemic disorders in various organs, and the fluorine added to drinking water accumulates in various plants (Gritsan et al. 1995) and insects (Gong and Shu 1991), creating toxicity and posing a threat to the ecosystem (Zuo et al. 2018). NaF, which is found to be the most common among toothpastes (n=105; 65%), may cause inflammation in human cells and leads osseous and soft tissue cells to apoptosis (Lee et al. 2008). After the fluorine (Vazquez-Alvarado et al. 2012), which has also been found to cause DNA damage in oral epithelial cells after oral application, reaches a toxic level in the body, not only the damage does not remain at the level of DNA and cell organelles, but also It is stated that pathological damage occurs in various organs such as liver, kidney, reproductive organ, heart, and thyroid (Zuo et al. 2018). Moreover, stannous fluoride may be able to caused structural and compositional changes in oral biofilm. According to metatranscriptomic analyzes, it has been reported that toothpaste with stannous fluoride causes genetic changes in the microbiota and creates a less pathogenic environment (Gumber et al. 2022). However, there is no more successful preventive agent against dental caries than fluoride (FDI World Dental Federation 2020).
Dental biofilm, which cannot be removed and then, accumulates on the teeth, turns into gingivitis and periodontitis in the later stages, resulting in tooth loss. The toothpastes not only cleans mechanically through the abrasives, but also creates antibacterial activity with the chemical components. Inflammation is quelled in this way. By interfering with the biofilm mechanism with substances that stop plaque development, it also aims to lessen biofilm pathogenicity (Cvikl and Lussi 2020). Inert materials are called abrasives that do not dissolve in liquids, allow speedy and efficient clearance of the biofilm layer on the teeth, and prevent extrinsic tooth discolouration (Lobene 1968). Similarly, agents with plaque-removing properties act on the biofilm tissue, protect the dental tissues against bacteria and fungi, inhibit their ability to adhere to the tissue and reduce the degree of inflammation (Mason et al. 2021). Some of the most important factors in the cleaning process of abrasives are the hardness of the particles, their size, sharpness, concentration and the amount of force applied during brushing. Furthermore, the diameter and shape of the bristles of the toothbrush are among the factors that would change the influence of the abrasive efficiency (Lippert 2013). In our study, the most common abrasive ingredients in the toothpastes were hydrated silica (n=146; 90%), calcium carbonate (n=14; %8) and sodium bicarbonate (n=28; 17%). Hyrated silica has plaque removal and discolouration reduction action (Schemehorn et al. 2011). On the contrary, it has an effect on softening enamel tissue, increasing the breakdown of that (Ganss et al. 2016). There is evidence that calcium carbonate can be harmful and toxic even at low amounts (Picolos and Orlander 2005). Calcium carbonate should not be used in conjunction with sodium fluoride, because it limits the quantity of fluoride that would release into the environment (Hara and Turssi 2017). Hydrated silica, which reacted less with other ingredients, was clearly recognized as the most widely utilized abrasive agent. As a result, it is not surprising that it is common in many pastes. However, there is no linear relationship between the addition of hydrated silica to the structure and the increase in abrasiveness degree (Ganss et al. 2016). From a clinical standpoint, tooth wear is unavoidable owing to increased life span and the duration of teeth in the mouth, and the abrasive efficiency of toothpastes in this process is undeniable (Hara and Turssi 2017). Each toothpaste has a distinct abrasive activity, which is measured in Relative Dentin Abrasivity (RDA) - Relative Enamel Abrasivity (REA) units. While the reliable RDA limit is expressed to be 250, the desired abrasive ingredients have a direct impact on the RDA value (International Organization for Standardization (ISO 11609) 2017). For instance, although it is known that toothpastes containing sodium bicarbonate exhibit low RDA values and have a softer effect in terms of abrasiveness, it is predicted that this may trigger the formation of a non-carious tooth lesion similar to dental erosion (Hara and Turssi 2017). RDA values imply that toothpaste should be 150-200 high abrasive, 70-150 moderately abrasive, and 70 low-abrasive (Giles et al. 2009). To prevent tooth wear, the toothpaste contains abrasive substances that are generally safe, such as calcium borosilicate alumina (Fiume et al. 2013). This ingredient is found in only one of the pastes tested in the study. In general, calcium silica-based compounds lower toothpaste's abrasive efficacy by converting to hydroxyapatite on the intact or degraded enamel surface, hence decreasing wear (Parker et al. 2014). In fact, calcium silica-based toothpastes have been shown to be far more successful in maintaining enamel than NaF or fluoride-free pastes. This effect can be explained by the fact that CaSi particles promote deposition, retention, and remineralization on the enamel surface (Buzalaf et al. 2021). With the introduction of calcium silica-based abrasives in toothpastes, the tooth wear caused by dentifrices may be avoided, besides the disadvantages of fluoride may be eliminated.
Pyrophosphates, sodium hexametaphosphate, and zinc salts are examples of substances that prevent supragingival deposition by inhibiting plaque crystallization (Chesters et al. 1998). While pyrophosphates are demonstrated to be the most widely utilized anti-calculus agents in toothpastes, the market analysis in 2019 revealed pyrophosphates as anti-calculus ingredients in 78 percent of 60 distinct toothpastes (Levine 2020). Pyrophosphate derivatives are found in only 25% (n=40) of the 160 different toothpastes in present study. Pyrophosphates consist of two phosphate atoms bonded to an oxygen atom. Pyrophosphates, which are widely used as disodium and tetrasodium, inhibit the formation of calculus by the chelation technique, and their toxicity has been shown to be minimal (Fleisch and Bisaz 1962; Levine 2020). Pyrophosphates, which also find a place in different therapies in the area of medicine (Abdelazim et al. 2022), tetrasodium pyrophosphate has been documented to be irritating to the eye and skin tissue (NIOSH 2011). Moreover, tetrapotassium pyrophosphate may induce contact stomatitis in oral tissues (DeLattre 1999). In addition, the di-structured phosphate type may have less abrasive, whitening, and plaque-removing efficacy than tetra due to geometric drawbacks (Vertuan et al. 2020). It has also been reported that calcium pyrophosphate is one of the important markers in determining the REA and RDA values (Kim et al. 2022). Since pyrophosphates have the ability to chelate with calcium ions in the oral environment, they can reduce the free calcium concentration, which is predicted to accumulate on the enamel in the de & remineralization cycle. Thus, it has been suggested that it may hinder enamel remineralization (Levine 2020). In recent years, few studies have been conducted to compare the anti-caries efficiency of pyrophosphate and non-pyrophosphate fluorinated dentifrices (Levine 2020). Sodium hexametaphosphate, which is to consist of longer chains of pyrophosphate, adheres better to the tooth surface due to the bonding of polymer chains with pellicle and inhibits the creation of new deposits on the surface compared to pyrophosphates (White and Gerlach 2000). The benefits of sodium hexametaphosphate include enhanced tartar management and whitening activities via a synergistic effect with fluorine (T. He et al. 2007), and it may be a good substitute for other pyrophosphate species.
Halitosis is caused by volatile sulfur contents in the oral area, and zinc salts react with sulfur agents to convert them into non-volatile salts, so removing bad breath (Young et al. 2003). Zinc salts, particularly zinc citrate, have antibacterial action, decrease plaque formation, and help to reduce the oral disease (Adams et al. 2003). The presence of aerobic and anaerobic microorganisms in dental plaque can be dramatically reduced by zinc citrate (Stephen et al. 1990). Zinc citrate, zinc lactate, and zinc gluconate are detected as anti-malodor components in our research. Zinc citrate is identified as the most prevalent agent (n=33; 20%). Diet has been cited as the key source of zinc salts consumption, which has a multifunctional function in the body (Vallee and Falchuk 1993). It has been shown that hazardous effects can occur with zinc-containing dietary supplements, and it has been recognized that zinc gluconate, in particular, is a gastrointestinal irritant (Andriollo-Sanchez et al. 2008). Because of their high solubility, zinc oxide nanoparticles applied to personal care products, beverages, toothpastes, and drugs as synthetic nanoparticles can be quickly absorbed and elicit toxicity in major organs and cell organelle malfunction (Elshama et al. 2018). Zinc oxide was found to induce DNA damage in brain cells (Dkhil et al., 2020), therefore the fact that it was found in just a small percentage of the toothpastes in present study is noteworthy (n=7; 4%).
According to a 53-year meta-analysis, potassium and strontium salts were used in toothpastes to treat dentin sensitivity in the early years. After the 2000s, it was revealed that arginine, calcium sodium phosphosilicate (Novamin), and stannous fluoride were utilized (Carolina Castro Martins et al. 2022). In our study, we observed that arginine was the most common ingredient (n=19; 11%) among the toothpastes, with a low ratio of calcium sodium phosphosilicate (n=3; 1.8%). Arginine reduces sensitivity by constructing a protective glycoprotein molecule with calcium and phosphate in the dentinal tubule (Arantes et al. 2019; Shiau 2012), it also protects against air stimulation (Carolina Castro Martins et al. 2022). In a previous study, it is ineffective against cold and tactile stimulation (C. C. Martins et al. 2020). Calcium sodium phosphosilicate, on the other hand, interacts in an aqueous environment, releasing calcium and phosphate ions in its structure. The dentinal tubules are then protected by an amorphous Ca-P mineral layer that inhibits dentin hypersensitivity, similar to hydroxyapatite (Burwell et al. 2009). When compared to arginine, novamin is more effective in relieving air discomfort, tactile pain, and is only somewhat effective at treating cold pain (Carolina Castro Martins et al. 2022). Furthermore, when used with whitening toothpastes, novamin has been proven to boost whitening effectiveness (Kakodkar et al. 2013). In several investigations comparing novamin and arginine, it is discovered that both compounds are superior to each other (Arantes et al. 2019). In this regard, while numerous approaches and protocols are employed to treat dentin hypersensitivity, it is not yet viable to conceive of the presence of a gold standard method (Moraschini et al. 2018). When combined with fluorite in the paste, arginine has been shown to trigger both gastrointestinal side effects (Grimble 2007) and metagenomic modifications on cariogenic and non-cariogenic beneficial bacteria (Carda-Diéguez et al. 2022). Additionally, it has been found that novamin has no adverse effects on oral tissues (Salian et al. 2010). Novamin is reported to be more biocompatible and tissue-friendly than arginine.
Multiple emulsifying, foaming, and surfactant ingredients are added to toothpastes to assure and enhance teeth cleaning and cleaning efficacy. SLS, Sodium laureth (lauryl ether) sulfate, Sodium coco sulfate, and Cocamidopropyl Betaine are examples of these compounds (Tateyama-Makino et al. 2021). These agents, which can be anionic, cationic, or amphoteric, impose pressure on microorganisms, decrease surface energy, and denature proteins thanks to their ability to foam and clean the surface (Jelinska et al. 2017; OHBU et al. 1980). In vivo studies have shown that SLS derivatives cause cell damage, hair loss, irritation to the skin and eyes, as well as harm to organs. This point should not be overlooked, and it should also be noted that numerous continents permit the limited use of SLS derivatives in several personal care products. (R. B. Brown and Razzaque 2018; Nikolaou and Golfinopoulos 2017; Tadin et al. 2019). In contrast to all of these, it has been determined that SLS-like agents are effective in suppressing COVID-19 infection via working to block ACE2 and TMPRSS2, which are the pathways that allow the virus to enter the cell. One method of preventing infection is to use toothpaste containing these ingredients (Tateyama-Makino et al. 2021). Sodium coco sulfate, which is sourced for the market as an alternative to SLS and is supposed to be more ecologically friendly, is not all that unlike SLS, and these agents are similar with regard to their formulation (Nikolaou and Golfinopoulos 2017). Because surfactants impede the bioactivity of calcium and phosphate, the use of SLS in the production of a toothpaste containing tricalcium phosphate is not advised from a chemical standpoint (Meyer et al. 2018). Our analysis reveal that SLS is present in two out of every three pastes (n=108; 67%), whereas Cocamidopropyl Betaine is present in one out of every two pastes (n=78; 48%). In a study measuring the cytotoxicity of these two agents at various concentrations, it is found that both agents caused high cytotoxicity of over 90 percent (Tabatabaei et al. 2019). Since these agents are also found to be associated with oral mucosa inflammations (Herlofson and Barkvoll 1993), it is important to minimize their exposure and concentrations in toothpastes.
Paraben and sodium benzoate are the most commonly utilized compounds in personal care products as preservatives and protective agents (Battino et al. 2005; Mazur et al. 2022). The great majority of toothpastes in this study do not include paraben (n=4), which may be found in a variety of toothpastes including methylparaben, ethylparaben, and propylparaben (Soni et al. 2005). Paraben can cause cancer by disturbing the endocrine system's balance and exhibiting estrogen-like properties (Qiu et al. 2020). It is also reported that large concentrations of ethylparaben are identified in urine due to its effect on the urinary system (S. Kim et al. 2018). In terms of oral and public health in Turkey, the presence of paraben in a negligible amount of toothpastes on supermarket shelves is a beneficial development. In addition, it is found that sodium benzoate, another preservative, was present in one-fourth of the pastes (n=41; 25%). Although sodium benzoate is described as a robust preservative (Mani and Thawani 2019), it has been shown in cell culture studies to be harmful to human gingival fibroblasts (Tabatabaei et al. 2019). In a cytotoxicity research with sodium benzoate, which was added to pastes in extremely small amounts by weight and the FDA's safety limit was claimed to be 1000 ppm (Lippert 2013), it was discovered that concentrations of 500 ppm and higher caused 100% mortality (Gaur et al. 2018)
White and odorless sodium saccharin is used to sweeten toothpastes since it is several times sweeter than sugar and sucrose (Gimba et al. 2014; Lippert 2013). Saccharin, which has been reported to be featured in the majority of toothpastes (Lippert 2013), was also found to be used almost always (n=147; 91%) in our study as a sweetener. Saccharin, an artificial sugar derived from petroleum, is insoluble in water and may have a carcinogenic impact with prolonged usage (Zhu et al. 2005). In present study, the majority of toothpastes include saccharin, which has been documented to induce skin allergy, cardiac, and gastrointestinal issues, may represent a public health risk. Titanium dioxide is the most often used ingredient as another ingredient in this study, and it causes severe negative effects. This chemical, which is discovered in 68% (n=111) of toothpastes in our investigation, is reportedly employed not just in pastes but also to impart a white tint to foods and modify the brightness of products (Baan 2007). It has been discovered that titanium dioxide, which is accepted to be ingested orally by young children between the ages of 2 and 6, is absorbed via the intestines and causes biological harm at the cellular and molecular level (Rompelberg et al. 2016). Since the concentration of titanium dioxide, which can be ingested not only through toothpaste but also through numerous food products (milk, cream, coffee, gum, sauce), can reach very high levels in the body, it is advantageous to avoid using it in toothpastes in order to minimize exposure (Rolo et al. 2022). It is notable that this substance is present in nearly two-thirds of toothpastes marketed in our country.
It has been observed that sorbitol and glycerin are the most frequently applied moisturizing agents in toothpaste, preventing the paste from drying out and giving it a smooth, glossy appearance. Additionally, it has been noted that both agents are utilized concurrently. The combination of both agents eliminates the structural drawbacks of the components and guarantees that the toothpaste is more stable, does not degrade, and retains its initial viscosity for an extended period of time (Lippert 2013). It has been stated that glycerine in toothpaste can give effective therapy for individuals with allergic rhinitis by activating the defense mechanisms in saliva (Reisacher et al. 2016). However, due to the presence of diethylene glycol and ethylene glycol in glycerine-containing goods, glycol units may be retained in the brain and renal tissue, causing toxicity (Self 2013). Xanthan gum, produced by Xanthomonas campestris, is a fermentation natural substance from edible carbohydrates (sucrose, starch, glucose) (Sworn 2021). It is a flavorless, cream-colored substance with excellent viscosity at low concentrations that may be employed as a solvent for different salt solutions. Its usage in the diet business in conjunction with carrageenan provides a benefit, although its use as a thickening in other products has produced swallowing issues (Hublik 2012). Xanthan gum, which was proven to produce flu-like illness (Fedoruk et al. 1990), was the second most prevalent thickening agent in our study (n=90; 55%). Carrageenan, on the other hand, is a form of polysaccharide derived from red seaweed that is incorporated in a variety of culinary goods, toothpaste, cosmetics, and insecticides. Carageenan is used in toothpaste as a binder to alter the paste's rheological qualities (Necas and Bartosikova 2013). It is considered a vegan alternative to gelatin and is included in herbal toothpastes (Mazur et al. 2022). It has been claimed that if it is not digested properly in the gastrointestinal system, it can produce tumor-like growth and ulceration, as well as having hazardous consequences at distinct rates (Necas and Bartosikova 2013).
One of the limitations of this study is the design of the study on which components are in the box of the paste. In certain instances, toothpaste manufacturers may conceal their secret components or formulae. In this work, the known and researched ingredients of a vast number of that were examined. Through various cell investigations on the components, in situ or in vivo studies, by producting on of experimental pastes, it should be determined if these agents have adverse effects and if they have synergistic effects when coexisting with other agents. Clinically, it is essential for physicians to understand what the toothpaste's constituents accomplish and to choose which toothpaste will produce the best outcomes in a certain circumstance. Numerous therapeutic chemicals are added to toothpaste, eliminating issues including dental cavities, erosion, gingivitis, and dentin sensitivity. The efficacy and detrimental effects of these drugs on live tissue should be examined in a range of techniques, and the results should be considered. Toothpastes, which safeguard oral health, are the clinicians most powerful instrument for the universal control of all oral disorders.