Dental care substances with stannous fluoride as an active ingredient may be helpful in allowing re-hardening or in increasing the resistance of teeth surfaces to further acidic or mechanical impacts. However, stannous fluorides are applied together with brushing and depending on how and when tooth-brushing occurs. This research focuses on the potential harmful and helpful effects associated with the use of stannous concerning erosive wear. Active ingredients like fluorides or agents that have unique anti-erosive properties were shown to offer protection against erosion and combined erosion and abrasion to some extent. The abrasive effects of dentifrices may increase the surface loss of eroded teeth. This research places greater emphasis on the use of Stannous fluoride. Most clinical evidence to date comes from deep and detailed studies that provide for a better understanding of the deep and intertwined interaction of active ingredients and abrasives and their effects on erosive tooth wear. Stannous fluoride is the only halogen fluoride source that provides protection against all three oral health conditions of gingivitis, tooth sensitivity, and tooth cavities. An analysis of these studies is the main focus of this paper. It gives in depth analysis of the efficacy of stannous fluoride in the prevention of dental erosion.
Dental erosion is a form of tooth wear that involved many protective and risk factors. The chemical, biological, behavioral factors interact with the surface of the teeth causing it to wear out or protect it based on the balance of the factors. When acid comes into contact with a tooth, it removes layers or demineralizes the enamel which mostly affecting the palatal and lingual surfaces. An increasing cause of tooth erosion is the intrinsic gastric acid reflux that comes from the stomach and enters into the mouth in gastroesophageal reflux disease. Although people are now adopting healthier diets, they are also putting themselves at risk of dental erosion by consuming acidic foods such as citrus fruits. The use of fluoride to make dental products has been encouraged for years because fluoride plays an important role in protecting tooth enamel. Stannous fluoride covers the enamel part of the teeth preventing it from corrosive substances that erode this part of the teeth making them weak and susceptible to pathogenic bacteria attack (Pharmacy Times, 2014). It boosts the natural protective substances in the mouth to prevent abrasion brought by the rising acidity level. The topic is relevant because of an estimated 15% of the population experienced gastric acid reflux symptoms weekly in Western and excessive consumption of acidic foods (Higham, 2014). Even tooth erosion initially involves no pathogenic bacteria; it can lead to complications such as hypersensitivity and dental decay if no protective interventions take place. The literature review is also crucial in determining the role of stannous fluoride in relating to tooth erosion. Stannous fluoride plays a significant role in inhibiting erosive hard tissue loss, known as dental erosion, mostly caused by gastroesophageal reflux disease.
Review of Literature
According to responses acquired during a US-based national survey on dental health, it was estimated that pharmacists make approximately one million stannous fluoride use recommendations per month to their patients and customers (Ganss and Schleuter, 2012). Due to these high quantities of recommendations for these products and the variety of products available, it has been made prudent that pharmacists understand the differences and benefits of the options available to them and their customers.
Research on dental health has shown that good dental hygiene has a good impact. Good oral health can occur through an overall dental hygiene that is most applicable at home. Maintenance of this state of oral hygiene can occur through the constant use of fluoride toothpaste. Regular recommendations by many pharmacists to their clients have an important role when clients are trying to find good dental products. Most oral care products have Fluorine as their active ingredient (Higham, 2014). Fluoride in toothpaste is available as sodium fluoride and stannous fluoride. Stannous fluoride delivers both cavity fighting fluoride and antibacterial properties that fight plaque and gingivitis. It is also a source of an anti-sensitivity mechanism of action.
It has been observed that Stannous fluoride has both bactericidal and bacteriostatic properties, which fight plaque and treat and prevent gingivitis (Pharmacy Times, 2014). In addition, the stannous fluoride delivers a protective mineral barrier over exposed dentinal tubules to help prevent sensitivity pain. The efficacy of stannous fluoride in dental health is evident in much scientific research studies on the use of solutions.
Recent evidence shows that stannous fluoride, as an aqueous solution and as toothpaste, can reduce the severe erosion of enamel in erosive acids inside or outside the mouth. Stannous fluoride works by mechanisms that occlude dentinal tubules inhibit fluid movement in these dentinal tubules and thus decreasing the eventual stimulation of the nerves. Clinical research supports the benefits of stabilized stannous fluoride dentifrice in controlling dentinal hypersensitivity (Pharmacy Times, 2014). Stannous fluoride works by occlusion of the dentinal tubules, inhibition of fluid movement in the tubules and the decrease in the sensitivity of teeth. Clinical Research supports the benefits of stabilized stannous fluoride dentifrice in controlling dentinal hypersensitivity (Limeback, 2012).
A study to assess the persistence of antimicrobial action of a number of stannous fluoride formulations in the mouth and relate these actions to plaque inhibitory activity was conducted. The formulations used were; 2 SF kinds of toothpaste (SF1, SF2), 2 SF plus stannous pyrophosphate toothpaste (SFSP1, SFSP2), an SF gel (G). Also, a NaF toothpaste and saline were used as a control. The studies involved two different groups of 21 healthy dentate volunteers. The studies were single, blind, randomized; crossover designs balanced for residual effects, with a minimum two and a half day washout period. Salivary bacterial counts were determined before and after a single rinse every seventh hour with the formulations. Regrowth of Plaque from a zero baseline (day 1) was measured by index and area on the fifth day five, after two times daily rinsing with gels of the formulations or saline solutions. For bacterial counts, highly significant treatment variations were found. Bacterial counts were variably reduced by all treatments to thirty minute. They then showed a variable rate of return towards baseline. All test agents were significantly better than Saline solution at some time points. The order for the greatest persistence of action downwards was; (1) SFSP2; (2) SFSP1, G, and SF1; (3) SF2; (4) C; (5) Saline. Highly meaningful differences in plaque regrowth between treatments were found with similar mean ordering of efficacy. For salivary bacterial counts, samples were placed from most effective downwards with labels as (1) SFSP-1 and SFSP-2; (2) SF-1; (3) SF-2; G and C; (4) Saline (Ganss and Schleuter, 2012).
The results were very similar to a parallel study that was measuring tea staining inside the mouth. The formulations that caused the most staining produced the greatest persistence of action and plaque inhibitory activity. This finding suggests the availability of stannous ions was important for the clinical effects. It is concluded that stannous ions can enhance the plaque inhibitory action of toothpaste via a persistent antimicrobial action (Limeback, 2012).
Another study was conducted to test the efficacy of dentifrice and gel both containing stannous fluoride. The method applied was to apply the solutions on healthy teeth and expose then to acids that cause erosion. 14 people with healthy teeth were contracted for the purpose of this study. After every seven days, the teeth were checked, and results recorded. It was then observed that the use of a daily two-step dentifrice and gel system showed a significant reduction in dental erosion and improvement in tooth color in comparison to regular oral hygiene. (Pharmacy Times, 2014).
The purpose of the third study was to measure, in the absence of dentifrice components, the relative ability of NaF and SnF2 solutions that were freshly prepared to reduce the acid solubility of powdered HAP. It was aimed to establish the relative ability of these active ingredients to reduce acid dissolution changes when incorporated into modern dentifrice formulations. An in-vitro dissolution model for HAP was used to measure in vitro dissolution kinetics of pretreated HAP, a synthetic mineral analog of teeth, under acidic solution conditions. This study, using a randomized, parallel group in situ design with in vivo product use and ex vivo acid challenge, compared to A. A dentifrice containing 1,450 parts per million of Fluoride as NaF; B, a dentifrice containing 1,450 parts per million of fluoride and T, tap water were the treatments used. Sample size was four per group with a total of 12 subjects. For every subject, the solutions were placed on each side of the mouth, that is left and right. Specimens of enamel were placed in varying positions of the mouth from the front, mid-front, mid-rear to the rear of the mouth in each appliance (total = 8 specimens per subject). Product treatment was twice per day (lingual brushing for 30 seconds. It was followed by swishing for 90 seconds with the resultant product/saliva slurry) in vivo for 15 days. Ex vivo acid treatment of 0.02 m citric acid 5 minutes four times per day and the total exposure time was 300 minutes. Data were analyzed using a general linear repeated measures model with treatment, side and position as fixed effects. Within subjects, correlations were modeled assuming a different correlation and variance for treatment B compared to the other groups. Treatment differences between pairs were performed using a 5% two-sided significance level. The results showed that enamel loss (in μm) was significantly lower for treatment B relative to treatments A and T. In Treatment B enamel surface loss was reduced by 86.9% in comparison to treatment A. There was no statistical difference in mean enamel loss between both the treatments. Enamel loss was not statistically different from side or position (Pharmacy Times, 2014).
In another long-term home use study on 143 volunteers that was done for 18 weeks, the results found no significant variations between stannous fluoride toothpaste and other test agents for the dental erosion index at 6 or 18weeks. However, there was a consistent pattern of decreasing erosion scores in all groups. This finding is not to say that clinical superiority is lacking for the test products in comparison to stannous fluoride agents. The home use methodology is more likely too insensitive to detect actual differences; this is primarily because subjects may carry out additional anti-erosion activities, which were masked by the Hawthorne effect.
Very interesting results were showed by the in vitro study by dental practitioner around the year 2013. They discovered that AmF, SnF2 or a combination of both AmF/SnF2 (solutions of stannous fluoride) enhanced the superoxide release from neutrophils by two- to three- folds. These results suggest that AmF and SnF2 enhance the oxygen-dependent antibacterial activity of neutrophils. They also harden the enamel tissue preventing any dental erosion.
The above case studies have proven that stannous fluoride is a valuable addition to the prevention against dental erosion. Many products containing stannous fluoride have shown varying degrees of effectiveness on pain resulting from exposed dentine. The effectiveness of such solutions is based on the deposition of a layer rich in stannous fluoride on the tooth surface and subsequent incorporation of stannous into the outermost tooth surface layers in the course of subsequent acid attacks. The initially formed layer contains amorphous stannous and fluoride and is usually partially dissolved, and complex de-mineralization and re-mineralization processes happen, leading to the incorporation of compounds with low solubility into the eroded enamel. There is an assumption that these compounds consist of different stannous and fluoride salts (Limeback, 2012). The studies conducted proved this point.
In the various studies done, there were difficulties in getting volunteers to have their teeth checked. The respondents could also alter the results by using other dental erosion preventive measures. The studies, however, have given a baseline for using stannous fluoride in preventing dental erosion. The have proved beyond reasonable doubt that the chemical has beneficial effects on teeth.
The studies have not given the longevity of a single appliance of stannous solutions. They give no information on when the stannous effect leaves the teeth. They also don’t have effects of other dental ailments to teeth treated with stannous fluoride.
Tooth erosion is extremely common and much more than a simple nuisance. There are significant possible downstream effects. All people are at risk of developing dental erosions. However, some are at high risk for a variety of reasons with many likely to be genetic. Having a person assign risk early in life, when true basic prevention is a possibility. It can be carried out by a Non-Dentist pediatric health care professional. In all the research studies done, stannous fluoride helps protect against the initiation and progression of dental erosion. Stannous fluoride delivers both cavity fighting fluoride and antibacterial properties that fight plaque and gingivitis. It is also a source of an anti-sensitivity mechanism of action. Stannous fluoride has the bactericidal and bacteriostatic properties. These properties fight plaque and treat and prevent gingivitis. Thus, a recommendation by dental professionals in favor of the use of stabilized, stannous-containing products as a means of giving assistance in the prevention of dental erosion is scientifically justified. Stannous fluoride may have some side effects on people and thus not prove preventive to them.
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