Tooth Remineralisation Mechanism

Demineralisation and remineralisation of dental enamel is conditioned by multiple variables, from the oral cavity’s PH, microbiome, saliva, enzymes, presence of minerals (calcium, phosphate, fluoride) and more. (Source)[1]

Tooth remineralisation is a naturally occurring process in the oral cavity.[2] It is defined as a process in which calcium and phosphate ions are sourced to promote ion deposition into crystal voids in demineralised enamel. Remineralisation remains imperative towards the management of non-cavitated carious lesions and prevention of disease progression within the oral cavity. The process also has the ability to contribute towards restoring strength and function within tooth structure.[3]

On the other hand, tooth demineralisation is a chemical process by which minerals (mainly calcium) are removed from any of the hard tissues: enamel, dentine, and cementum.[4] The process of demineralization begins at the crystal surface found inside the hard tooth tissue and may progress into cavitation unless arrested or overridden by remineralisation. The effect of demineralisation can be reversed if there is sufficient time to allow remineralisation to occur to counteract the acids in the oral cavity.[5] Demineralisation and remineralisation constitute a synergistic and dynamic process.[6]

The Tooth decay process

The initiation of the caries process is triggered by an increase in the acidity of bacterial plaque. In other words, the process of dental caries occurs when the acid-producing bacteria found in dental plaque on teeth feed on fermentable carbohydrates and produce organic acids as by-products. [7] The acids diffuse into the tooth surface and dissolve the carbonated hydroxyapatite mineral that consecutively forms a carious lesion. When food or drinks containing sugars enter the mouth, the bacteria within the plaque rapidly convert the sugars into acid. The plaque can hold the acid in contact with the tooth surface for up to two hours before it is neutralised by saliva. During the time that the plaque is acidic, some of the calcium and phosphate minerals are dissolved out of the enamel into the plaque and once the plaque acid has been neutralised the minerals can return to the enamel surface. However the capacity for remineralisation is limited and if sugars enter the mouth too frequently a net loss of mineral from the enamel surface results in a cavity through which bacteria can penetrate and infect the inner structure of the tooth.[4] Although a key feature of tooth decay is the increase of bacteria such as Streptococcus mutans and Lactobacillus in dental plaque, it is not considered as an infectious disease.[4]  

Tooth decay can be managed by modifying behavior and controlling its causative factors, i.e. reducing the intake frequency of fermentable carbohydrates from food, eating the right foods and living holistically. This will reduce the chance of the dental biofilm developing into cariogenic biofilm. The bacteria in cariogenic biofilm produce organic acids when carbohydrates, especially sugar, are eaten. When enough acid is produced so that the pH goes below 5.5, the acid dissolves carbonated hydroxyapatite, the main component of tooth enamel, in a process known as demineralisation.[8] After the sugar is gone, the mineral loss can be recovered—or remineralised—from ions dissolved in the saliva. Cavities result when the rate of demineralisation exceeds the rate of remineralisation and the latticework is destroyed, typically in a process that requires many months or years.[9]

Natural Tooth Remineralisation

Role of saliva

Saliva, being the watery substance that constantly circulates the oral cavity, is capable of impacting both the remineralisation and demineralisation processes. It is secreted through the major salivary glands including the parotid, submandibular, sublingual and Von Ebner’s glands as well as the hundreds of minor salivary glands that are located throughout the oral cavity.[10]

Remineralization occurs on a daily basis after an acidogenic challenge through the presence of saliva.[11]Calcium, phosphate and fluoride found in saliva, are required for effective remineralization and maintenance of the enamel surface integrity.[11] Therefore, as saliva is rich in calcium and phosphate ions, it can act as a natural buffer to neutralise acid and allow demineralised tooth tissues to be remineralised.[4] If there is reduced saliva flow or reduced saliva quality, this will increase the risk of demineralization and create the need for treatment in order to prevent demineralisation progression.[4]

Saliva function can be organised into five major categories that serve to maintain oral health and create an appropriate ecologic balance: Lubrication and protection: Buffering action and clearance; Maintenance of tooth integrity; Antibacterial activity; Taste and digestion.[4]

As the demineralisation process continues, the pH of the mouth becomes more acidic which promotes the development of cavities. Dissolved minerals then diffuse out of the tooth structure and into the saliva surrounding the tooth. The buffering capacity of saliva greatly impacts the pH of plaque surrounding the enamel, thereby inhibiting caries progression. Plaque thickness and the number of bacteria present determine the effectiveness of salivary buffers.[4] The high salivary concentrations of calcium and phosphate which are maintained by salivary proteins may account for the development and remineralisation of enamel. The presence of fluoride in saliva speeds up crystal precipitation forming a fluorapatite- like coating which will be more resistant to caries.[4]

Tooth Remineralisation Treatments & Preventative Strategies

Besides professional holistic dental care, hereinafter a few other less remineralisation techniques.

Fluoride helps to catalyze remineralisation of teeth

 

Section Under construction

 

Natural Fluoride versus Synthetic Fluoride

The natural version of fluoride is known as calcium fluoride (CaF2), which is naturally found in soil and in moderate abundance in tea leaves, wine and potatoes. On the other hand, synthetic Fluoride (Sodium Fluoride (NaF)) is toxic and not recommended. The term “fluoride” is a cover-up name for many of the toxic chemicals that make up fluoride, including lead, arsenic, aluminum, cadmium, fluorosilicic acid and even radioactive materials. The pure form of sodium fluoride is so toxic that by just consuming a small volume of it can kill a human being. There is enough fluoride in one tube of toothpaste to kill two small children. This is why fluoridated toothpastes have warning labels on them and fluoride-free toothpastes do not. Sodium fluoride is even more toxic than certain forms of rat poison – in fact, sodium fluoride is one of the main chemicals in pesticide, insecticide and fungicide for this very reason. As described at PreventDisease.com:

“The fluoride added to 90% of drinking water is hydrofluoric acid which is a compound of fluorine that is a chemical byproduct of aluminum, steel, cement, phosphate, and nuclear weapons manufacturing (….) Hydrofluoric acid is used to refine high octane gasoline, to make fluorocarbons and chlorofluorocarbons for freezers and air conditioners, and to manufacture computer screens, fluorescent light bulbs, semiconductors, plastics, herbicides, and toothpaste.”

On other hand natural fluoride is a mineral found naturally in rock, air, soil, plants and water and it assists by protecting children and adults against tooth decay, repairing early white spot lesions found on the tooth surface that may develop into cavities. It can also helps prevent premature tooth loss of baby teeth due to decay and overall assists in guiding the adult teeth to correct tooth eruption. Aids in the prevention of invasive dental treatment therefore reducing the amount of money spent on dental treatment.

Fluoride therapy is often used to promote remineralisation. This produces the stronger and more acid-resistant fluorapatite, rather than the natural hydroxyapatite. Both materials are made of calcium. In fluorapatite, fluoride takes the place of a hydroxide.[12]

Section under construction

Plaque control

Oral hygiene practices involve the mechanical removal of plaque from hard tissue surfaces[23] Cariogenic bacteria levels in the plaque determine whether caries will occur or not, therefore, effective removal of plaque is paramount.[24] The removal of plaque inhibits demineralisation of teeth, and inversely increases opportunities for remineralisation.

Diet

Demineralization is caused by bacteria excreting acids as a product of their metabolism of carbohydrates. By reducing the intake frequency of carbohydrates in an individual’s diet, remineralization is increased and demineralization is decreased. Diet control is an important aspect in promoting remineralization to occur naturally. A loss of the tooth enamel structure and cavitation may occur if the demineralization phase continues for a long period of time. This disturbance of demineralisation caused by the presence of fermentable carbohydrates continues until the saliva has returned to a normal pH and had sufficient time to penetrate and neutralize the acids within any cariogenic biofilm present.[25]

Increased sugar consumption in the means of foods and drinks containing high levels of sugar are known to be associated with high rates of dental decay. As a result, members of the dental team routinely assess patients’ diets and highlight areas where this could be improved to reduce the risk of dental decay. A balanced diet is an important contributing factor towards oral health and general health. It is common knowledge that certain dietary habits contribute to disease, whether patients take note of advice which is given to them and change their diet as a result, is less certain.[26]

It has been concluded in modern societies that a significant relationship between sugars and caries persists despite the regular widespread use of fluoride toothpaste.[27] Several reviews conclude that high sugar consumption continues to be the main threat for dental health of whole populations in some developed and many developing countries. Therefore, a key strategy to further reducing levels of caries in individuals as well as for populations, is by means of reducing the frequency of sugar intakes in the diet.

Foods high in refined carbohydrates, such as concentrated fruit snack bars, sweets, muesli bars, sweet biscuits, some breakfast cereals and sugary drinks including juices can contribute to dental decay, especially if eaten often and over long periods as the sugar nourishes the cariogenic bacteria in mouth. The bacteria produce acid, which destroys teeth. Highly refined packaged foods such as savory crackers and chips can also have high levels of carbohydrates. It is important to check the nutritional information panel on packaged foods to determine which foods and drinks have high carbohydrate concentrations.[28]

To prevent demineralisation in the mouth, it is important for an individual to ensure they have a well-balanced diet, including foods containing calcium and foods that are low in acids and sugars. The individual should have a diet high in fresh fruits and vegetables, wholegrain cereals, legumes, seeds and nuts. Sugary snacks including lollies, fruit bars, muesli bars, biscuits, dried fruit, cordials, juices and soft drinks should be limited as they contribute to dental decay and dental erosion. Additionally, excessive starchy foods (such as bread, pasta, and crackers), fruits and milk products consumed frequently can cause the growth of dental plaque and bacteria.[28] Therefore healthy eating, healthy drinking and proper maintenance of oral hygiene is the best way to promote and maintain sound tooth structure for an individual.

Phytic Acid

Section under construction

Xylitol & Chewing

Xylitol is a natural sweetener, also known as a sugar alcohol.[11] Xylitol inhibits acid production by oral bacteria and promotes remineralisation of the teeth.[11] It can be found in various products which include chewing gums and lozenges. Xylitol has been found to reduce mutans strepococci in plaque and saliva and reduce the binding of these to the acquired enamel pellicle.[11] This in turn leads to less adherent plaque and a decrease in acid production.[11] In addition, chewing xylitol gum will stimulate increased salivary flow which in turn increases the amount of calcium in the saliva and enhances the oral clearance.

Additional saliva flow which includes chewing products such as gums that contain no fermentable carbohydrates can aid in the modulation of plaque pH. Sugar free xylitol is recommended for uses to prevent caries formation. Indeed, research has shown that the use of gum containing xylitol reduces plaque accumulation and gingival inflammation and enhances remineralisation process.[29]

References

1. Featherstone, J. D. B. (2008). “Dental caries: A dynamic disease process”. Australian Dental Journal53 (3): 286–291. doi:10.1111/j.1834-7819.2008.00064.xPMID 18782377

2.  Fejerskov, O., Nyvad, Bente, & Kidd, Edwina A. M. (2015). Dental caries : The disease and its clinical management (Third ed.).

3.  Cochrane NJ, Cai F, Huq NL, Burrow MF, Reynolds EC. New approaches to enhanced remineralization of tooth enamel. Journal of Dental Research. 2010 Nov 1;89(11):1187-97

4. Li X, Wang J, Joiner A, Chang J. The remineralisation of enamel: a review of the literature. Journal of dentistry. 2014 Jun 30;42:S12-20

5. Garcia- Godoy, F. & Hicks, J. (2008). Maintaining the integrity of the enamel surface. American Dental Association, 139(3).

6.  Hicks J, Garcia-Godoy F, Flaitz C. Biological factors in dental caries: role of saliva and dental plaque in the dynamic process of demineralization and remineralization (part 1). Journal of Clinical Pediatric Dentistry. 2004 Sep 1;28(1):47-52

7.  Featherstone JD. Dental caries: a dynamic disease process. Australian dental journal. 2008 Sep 1;53(3):286-91.

8. Fejerskov O, Nyvad B, Kidd EA: Pathology of dental caries; in Fejerskov O, Kidd EAM (eds): Dental caries: The disease and its clinical management. Oxford, Blackwell Munksgaard, 2008, vol 2, pp 20-48.

9. Soi S, Roy AS, Vinayak V. Fluorides and Their Role in Demineralization and Remineralization. Principal’s Message.:19

10. Nanci, A., & Ten Cate, A. (2008). Ten Cate’s oral histology. St. Louis, Mo.: Mosby Elsevier.

11. García-Godoy, Franklin; Hicks, M. John (2008-05-01). “Maintaining the integrity of the enamel surface: The role of dental biofilm, saliva and preventive agents in enamel demineralization and remineralization”The Journal of the American Dental Association. 139, Supplement 2: 25S–34S. doi:10.14219/jada.archive.2008.0352.

12. Better health channel. “Dental care – fluoride”, April 2012. retrieved on 2016-04-15.

13. Pizzo, G.; Piscopo, M. R.; Pizzo, I.; Giuliana, G. (2007). “Community Water Fluoridation and Caries Prevention: A Critical Review” (PDF). Clinical Oral Investigations11 (3): 189–193. doi:10.1007/s00784-007-0111-6PMID 17333303.

14.  Aoba, T.; Fejerskov, O. (2002). “Dental Fluorosis: Chemistry and Biology”. Critical Reviews in Oral Biology & Medicine13 (2): 155–70. doi:10.1177/154411130201300206PMID 12097358.

15. Cury, J. A.; Tenuta, L. M. A. (2008). “How to Maintain a Cariostatic Fluoride Concentration in the Oral Environment”. Advances in Dental Research20 (1): 13–16. doi:10.1177/154407370802000104PMID 18694871.

16.  Hellwig, E.; Lennon, Á. M. (2004). “Systemic versus Topical Fluoride”. Caries Research38 (3): 258–262. doi:10.1159/000077764PMID 15153698.

17. Dr RS Levine. “The British Fluoridation Society”, A guide to the action of fluoride in the prevention of dental decay, 2016. retrieved on 2016-05-3.

18. Li, Xiaoke; Wang, Jinfang; Joiner, Andrew; Chang, Jiang. “The remineralisation of enamel: a review of the literature”Journal of Dentistry42: S12–S20. doi:10.1016/s0300-5712(14)50003-6.

19. Iijima, Y. (2008). “Early detection of white spot lesions with digital camera and remineralization therapy”. Australian Dental Journal53 (3): 274–280. doi:10.1111/j.1834-7819.2008.00062.xPMID 18782375.

20.  Beltrán-Aguilar; Goldstein; Lockwood (2000). “Fluoride Varnishes: A Review of Their Clinical Use, Cariostatic Mechanism, Efficacy and Safety: A Review of Their Clinical Use, Cariostatic Mechanism, Efficacy and Safety”. The Journal of the American Dental Association131 (5): 589–596.

21. Wiegand, A; Bichsel, D; Magalhães, AC; Becker, K; Attin, T (Aug 2009). “Effect of sodium, amine and stannous fluoride at the same concentration and different pH on in vitro erosion”. Journal of Dentistry37 (8): 591–5. doi:10.1016/j.jdent.2009.03.020.

22. National health and medical research council. “Health effects of water fluoridation”, 2016-04-06. retrieved on 2016-04-11.

23. Darby ML, Walsh M. Dental hygiene: theory and practice. Elsevier Health Sciences; 2014 Apr 15.

24. Hicks, John; Garcia-Godoy, Franklin; Flaitz, Catherine (2003-01-01). “Biological factors in dental caries: role of saliva and dental plaque in the dynamic process of demineralization and remineralization (part 1)”. The Journal of Clinical Pediatric Dentistry28 (1): 47–52. doi:10.17796/jcpd.28.1.yg6m443046k50u20ISSN 1053-4628PMID 14604142.

25.  Arathi Rao, Neeraj Malhotra. “The Role of Remineralizing Agents in dentistry: A Review”. Volume 32, Number 6. 2011. retrieved on 2016-05-22.

26. Moynihan, Paula; Erik Petersen, Poul (2004). “Diet, nutrition and the prevention of dental diseases” (PDF). Public Health Nutrition7 (1a): 201–226. doi:10.1079/PHN2003589PMID 14972061. Retrieved 22 May 2016.

27. Cury, J; Tenuta, L (24 Jan 2014). “Evidence-based recommendation on toothpaste use”Brazilian Oral Research28: 1–7. doi:10.1590/S1806-83242014.50000001. Retrieved 23 May 2016.

28. ”Eating habits for a healthy smile and body” (PDF). The Journal of the American Dental Association141 (12): 1544. Jan–Feb 2011. doi:10.14219/jada.archive.2010.0115. Retrieved 22 May 2016.

29.  Humphrey, S. & Williamson, R. (2001). A review of saliva: Normal composition, flow, and function. The Journal of Prosthetic Dentistry, 85(2), 162-169.

Further reading

Chow, L. (2010). “Diffusion of Ions Between Two Solutions Saturated With Respect to Hydroxyapatite: A Possible Mechanism for Subsurface Demineralization of Teeth” (PDF). Journal of Research of the National Institute of Standards and Technology. National Institute of Science and Technology. 115 (4): 217–224. doi:10.6028/jres.115.015PMC 2966276Freely accessiblePMID 21037801.

 

Exhibit A

Essential Oils potentiate fluoride

J Am Dent Assoc. 2004 Feb;135(2):231-7.

The remineralizing effect of an essential oil fluoride mouthrinse in an intraoral caries test.

Zero DT1, Zhang JZ, Harper DS, Wu M, Kelly S, Waskow J, Hoffman M.

Author information

Abstract

BACKGROUND:

The authors conducted a two-week clinical study to determine the remineralizing effect of an experimental mouthrinse containing both fluoride and essential oils in an intraoral caries test model.

METHODS:

The study used an observer-blinded, randomized, controlled, 3 x 3 crossover design. The authors enrolled in the study 153 subjects, each of whom had a mandibular removable partial denture. Two partially demineralized human enamel specimens were mounted on each subject’s removable partial denture. Subjects used either a fluoride mouthrinse with essential oils (the test mouthrinse), a fluoride nonessential oils mouthrinse (the positive control) or an essential oil nonfluoride mouthrinse (the negative control) twice daily for 14 days. The researchers assessed specimens for mineral content change and fluoride uptake using surface microhardness, or SMH, testing and enamel fluoride analysis, respectively.

RESULTS:

Of the 153 subjects enrolled in the study, 125 subjects were evaluable at the study endpoint. The results after two weeks showed that percentage of SMH recovery was 42 percent in the test group, 36 percent in the positive control group and 16 percent in the negative control group. The fluoride uptake was 19 micrograms per square centimeter, 16 microg/cm2 and 3 microg/cm2 for the test mouthrinse, positive control and negative control groups, respectively. In terms of both percentage of SMH and fluoride uptake, the test mouthrinse and positive control mouthrinse were statistically higher than the negative control mouthrinse, and the test mouthrinse was “at least as good as” the positive control mouthrinse.

CONCLUSIONS:

This study provides evidence that an essential oil mouthrinse with 100 parts per million fluoride is effective in promoting enamel remineralization and fluoride uptake.

CLINICAL IMPLICATIONS:

The combination of fluoride and essential oils in a mouthrinse may provide anticaries efficacy, in addition to essential oils’ previously established antigingivitis efficacy.

EXHIBIT B

Sodium Fluoride and Toxicity

Translate »
error: Content is protected !!