Dental hypersensitivity is a major, common dental condition that occurs in approximately 57% of adults. Among individuals with periodontal disease, the prevalence can reach as much as 98% . The condition usually arises as a result of continuous teeth erosion brought about by the action of foods, drinks and hot and cold temperatures that expose the dentin and underlying nerves, as shown in Figure 1A. As a result, external stimuli are transmitted to the nerves, causing brief but intense pain.
Dental hypersensitivity is usually treated by applying desensitizing toothpastes mainly composed by strontium chloride or potassium nitrate. However, these products do not simulate the natural composition and structure of dentin and enamel .
The mineralized tissues found in the human body are mostly composed of hydroxyapatite (HA), a natural calcium phosphate ceramic that is abundant in dentin (70%), enamel (97%) and bone (60%). Tooth enamel is the hardest tissue in the human body and is made up of building blocks of HA nanocrystals, 40nm in size. The tissue is acellular and unlike bone, cannot be naturally repaired . Regenerating the surface of tooth enamel therefore poses a significant challenge.
In the past few years, considerable advances in the field of nanotechnology have led to a large number of nanomaterials being developed. In the healthcare sector, these novel materials are known to enhance the performance of diagnosis, treatments and disease prevention.
Nanohydroxyapatite (nanoHA) is one such material that is being utilized in medicine and dentistry, owing to its excellent bioactivity and biocompatibility as well as its similarity to the mineral component of teeth and bone. This calcium phosphate is already being used in oral care formulations and offers a number of benefits, such as effective reduction of teeth sensitivity [3, 4], fast enamel remineralization [5-7] and improved smoothness of tooth surface and whitening [8, 9].
Unlike microsized HA, the tiny nanoHA is easily integrated into the dental tubules, enhancing their occlusion (Figure 1B). This seals the tubules and prevents exposure of the nerves to external stimuli, thereby reducing dental hypersensitivity. Moreover, nanoHA has a higher surface area, biological activity and chemical reactivity, which facilitate its binding to the dentin apatite and tooth enamel. This creates a new apatite layer that remineralizes the enamel and protects the surface of the tooth. This layer protects the tooth from the damage caused by acids in food and drink (Figure 1C) as well as whitening the tooth and making it smoother, as shown in Figure 1D .
Figure 1. (A) Exposure of dentin tubules to hot and cold temperatures stimulates nerves and causes pain; (B) nanoHA fills dentin tubules binding chemically to dental structure reducing hypersensitivity; (C) nanoHA remineralizes the tooth enamel protecting it against acid attacks from food and beverages; (D) improved smoothness and whitening due to enamel repair by nanoHA.
nanoXIM•CarePaste: Enamel Repair Ingredient
The nanoXIM•CarePaste is a nanocrystalline HA paste produced and marketed by FLUIDINOVA. This synthetic nanoHA aqueous paste has been specifically made for oral care applications, such as mouthwashes, toothpastes and chewing gums. The product contains high purity nanoparticles under 50 nm in size and with a high specific surface area. nanoXIM•CarePaste is naturally preserved and complies with dentifrices and food-grade standards.
A number of studies have been conducted to demonstrate the effectiveness of nanoXIM•CarePaste at reducing dental hypersensitivity and promoting enamel remineralization.
Effect of nanoXIM•CarePaste on Dental Hypersensitivity
To demonstrate the efficacy of nanoXIM•CarePaste in dentin tubule occlusion, an in vitro study was carried out using artificial saliva and human teeth. In this study, two toothpastes with varying concentrations of nanoXIM•CarePaste were compared with a regular toothpaste . The results showed that the two toothpastes containing nanoXIM•CarePaste occluded more dental tubules than the regular toothpaste did. In fact, after seven applications, the toothpaste containing nanoXIM•CarePaste occluded up to 75% of the dentin tubules (Figure 2).
Another study demonstrated the effectiveness of nanoXIM•CarePaste in occluding dentin tubules as well as showing that the product is sustained even after washing .
Dentifrices that contain nanoXIM•CarePaste are therefore excellent at promoting dentin tubule blockage and reducing dental hypersensitivity.
Figure 2. (A) Comparison of dentin tubule occlusion with regular and nanoXIM toothpastes. (B) Light microscope images illustrating the dentin tubules before and after the treatment with a nanoXIM•CarePaste dentifrice.
To test the rates of dentin tubule occlusion, another in vitro study compared a dentifrice containing nanoXIM•CarePaste with Colgate Pro-ReliefTM Pro-ArginTM technology.
nanoXIM•CarePaste-based toothpaste from Aclaim, Group Pharmaceuticals led to a high degree of tubule occlusion after just two minutes (Figure 3), which was five times faster than the occlusion rate seen with Colgate Pro-ReliefTM .
This further demonstrates that nanoXIM•CarePaste is an excellent product for blocking dentin tubules and reducing hypersensitivity.
Figure 3. Effect of Colgate Pro-Relief TM and nanoXIM•CarePaste-based toothpaste on dentin tubule occlusion after two minutes of treatment. A sample without treatment (control) was also analyzed. Data gently provided by Group Pharmaceuticals Ltd., India
An in vivo clinical study of 45 patients was performed to test the efficacy of nanoXIM•CarePaste (Aclaim), potassium nitrate (Sensodent-K) and propolis dentifrices in controlling dental hypersensitivity . Propolis is a natural, non-toxic resin than can occlude dentin tubules and reduce their permeability, whilst potassium nitrate is known for reducing dentinal sensory activity. The Visual Analog Scale for Pain was used to test the patients’ dentin hypersensitivity before and after using the different dentifrices.
Figure 4 shows the results after one and four weeks of treatment using the three different dentifrice varieties.
A greater pain reduction was observed among the patients treated with the nanoXIM•CarePaste dentifrice than with the other two varieties, suggesting that a formulation containing nanoXIM•CarePaste is the most likely to reduce dental hypersensitivity.
Figure 4. Reduction of dental hypersensitivity after treatment with potassium nitrate (Sensodent-K), Propolis and nanoXIM•CarePaste (Aclaim) during one and four weeks.
Effect of nanoXIM•CarePaste on Enamel Remineralization
An in-vitro study was performed to test the remineralization potential of a nanoXIM•CarePaste-based toothpaste compared with a Casein PhosphoPeptide-Amorphous Calcium Phosphate (CPP-ACP) dentifrice .
For the study, carious lesions were created in teeth by exposing them to demineralizing solution for 96 hours. The teeth were then treated using the two different dentifrices. The carious lesions were assessed using a diode laser fluorescence device called the DIAGNOdent Pen. The lower the value displayed by the DIAGNOdent pen, the greater the remineralization of the carious lesion. Figure 5 shows that nanoXIM•CarePaste was significantly more effective at remineralizing the lesion than the CPP-ACP dentifrice.
nanoXIM•CarePaste promotes crystal growth and its integrity helping to create a new crystalline, remineralized surface.
Figure 5. nanoXIM•CarePaste has greater effect than CPP-ACP dentifrice in remineralizing the early carious lesion. Data gently provided by Group Pharmaceuticals Ltd., India
nanoXIM•CarePaste is an excellent product to include in oral care formulations, effective at occluding dentin tubules and reducing dental hypersensitivity. The product achieves a higher rate of dental tubule occlusion than other commercial brands and remains on the teeth even after washing. Moreover, nanoXIM•CarePaste can repair damaged enamel and promote remineralization and the new biomimetic apatite layer formed by nanoHA helps to create a whiter and smoother tooth surface.
- Yuan P, Shen X, Liu J, Hou Y, Zhu M, Huang J, et al. Effects of Dentifrice Containing Hydroxyapatite on Dentinal Tubule Occlusion and Aqueous Hexavalent Chromium Cations Sorption: A Preliminary Study. PLoS ONE. 2012;7(12):e45283.
- Group Pharmaceuticals Ltd. Aclaim® Product Notes. 2012
- Browning WD, Cho SD, Deschepper EJ. Effect of a Nano-Hydroxyapatite Paste on Bleaching-Related Tooth Sensitivity. Journal of Esthetic and Restorative Dentistry. 2012;24(4):268-76.
- Ohta K, Kawamata H, Ishizaki T, Hayman R. Occlusion of Dentinal Tubules by Nano-Hydroxyapatite. Journal of Dental Research. 2007;86:529-33
- Huang S, Gao S, Yu H. Effect of nano-hydroxyapatite concentration on remineralization of initial enamel lesion in vitro. Biomedical Materials. 2009;4(3):034104.
- Li L, Pan H, Tao J, Xu X, Mao C, Gu X, et al. Repair of enamel by using hydroxyapatite nanoparticles as the building blocks. Journal of Materials Chemistry. 2008;18(34):4079-84.
- Jeong S, Jang S, Kim KN, Kwon H, Park YD, Kim B. Remineralization potential of new toothpaste containing nano-hydroxyapatite. Key Engineering Materials. 2006;309:537-40.
- Takikawa R, Fujita K, Ishizaki T, Hayman R. Restoration of post-bleach enamel gloss using a non-abrasive, nano-hydroxyapatite conditioner. Proceedings of 84th General Session & Exhibition of the IADR. 2006.
- Jiang T, Ma X, Wang Z, Tong H, Hu J, Wang Y. Beneficial effects of hydroxyapatite on enamel subjected to 30% hydrogen peroxide. Journal of dentistry. 2008;36(11):907-14.
- FLUIDINOVA SA. nanoXIM•CarePaste brochure. 2012.
- Marco R, Molina J, Gil F, Iborra I, Martí M, Alpiste F. Estudio In Vitro del Efecto Sellante de la Hidroxiapatita en Nanoparticulas para el Tratamiento de la Sensibilidad Dentinaria. 46ª SEPA Annual Meeting, Madrid, Spain. 2012.
- Hedge A. Dentin Hypersensitivity: a claim for relief?. 11th ISP Post Graduate Convention, Lucknow, India. 2012.
- Narmatha VJ, Thakur S. An In-vivo Comparative Study of the Efficacy of Propolis, Nano-Hydroxyapatite and Potassium Citrate Containing Desensitizing Agents. Research & Reviews: Journal of Dental Sciences. 2014;2(2):113-18.
- Mehta A. Toothpaste Comparison – Remineralization Effect. 26th FODI & 19th IES National Conference, Faculty of Dental Sciences, Jamia Milia Islamia University, New Delhi, India. 2011.
FLUIDINOVA manufactures synthetic nanocrystalline HA materials commercialized under the brand name nanoXIM. FLUIDINOVA produces highly pure, single phase nanoHA materials supplied worldwide as pastes for Oral Care formulations such as toothpastes, mouthwashes and chewing gums. Other applications for nanoXIM include powders and pastes for the manufacture of Medical Devices, Cosmetics, Drug Delivery, Pharma and Biotech. Currently nanoXIM is also incorporated in several FDA approved and CE mark medical devices.
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