The untold secrets of managing dentinal hypersensitivity (part 2)

Editor's note: Part one of this series may be found here.

Dentinal hypersensitivity (DH) undoubtedly affects a significant portion of the population. This common clinical condition touches all age groups. Despite extensive investigation of DH, this disorder remains underdiagnosed and underreported.¹ This annoying disease can lead to physical and psychological problems for patients and impact their quality of life. 

There have been many hypotheses proposed in an attempt to understand pain mechanisms related to DH; however, the most commonly accepted physiological explanation for this clinical disease is the hydrodynamic theory.^2–4 Interestingly, in a recent study Anderson and colleagues noted that hypersensitive teeth, when compared to nonsensitive teeth, have roughly eight times the number of tubules per unit and wider tubule diameters.⁴ Pain associated with DH is highly subjective, and patients can experience very minor discomfort or be subjected to severe agony.³ Because there are a host of etiological factors associated with DH and patients experience a range of discomfort levels, there is no recognized gold standard for treatment. The ideal desensitizing agent should be fast-acting, nonirritating, painless, and easy to use; provide long-term effects; and should not stain the teeth.⁵ Part one of this article series discussed the usage of fluoride varnish for the management of dentinal hypersensitivity, yet this treatment does not provide relief for all hypersensitive teeth. As such, additional therapies must be considered for clinical management of the condition. 

Clinical management

Miglani and colleagues proposed that an often-neglected phase of clinical management is removing the causative factors that would prevent DH from occurring or reoccurring.⁵ These causative factors include improper toothbrushing, poor oral hygiene, malocclusion, periodontal disease, lifestyle, and diet. In order for dental health-care personnel (DHCP) to identify these etiological factors, they must designate time during the dental appointment to conduct a thorough medical, dental, and social history. It is also necessary for DHCP to provide nutritional counseling to their patients using a one- or three-day food diary. When removal of the causative agent proves to be ineffective, as a second line of defense against DH, DHCP should recommend an at-home desensitizing agent, which typically involves the use of toothpastes, mouthwashes, and chewing gum. At-home therapies are typically the most cost- effective for the patient. The most common ingredient in toothpastes is 5% potassium nitrate.⁶ The potassium ions penetrate the tubules and decrease the excitability of the nerve.

Incorporating bioglass into toothpaste formulations has shown positive results in the treatment of DH. There is sufficient evidence in the published literature that proves incorporating bioglass into toothpaste occludes dentinal tubules.⁷ Bioglass is composed of specific percentages of silicon, sodium, calcium, phosphorus oxides, and, on occasion, fluoride. When the bioglass material comes in contact with the saliva, a protective layer of hydroxyapatite is formed over the tooth, mechanically occluding the tubules and decreasing the flow of fluid within the tubules.⁷ In addition to potassium nitrate and bioglass, various fluoride solutions have been incorporated in toothpastes and mouth rinses to treat DH, including sodium fluoride, stannous fluoride, sodium monofluorophosphate, fluorosilicates, and fluoride combined with iontophoresis, all of which act to seal the dentinal tubules or form coagulates inside the tubules.⁵ 

Oxalates can be very effective in treating DH. Oxalates are organic substances found in plants, and they work to treat hypersensitive teeth by blocking the flow of fluid in the dentinal tubules by means of occluding the tubules, reducing the patient’s perception of pain to external stimuli.^1,6 Oxalates can be delivered via toothpastes, mouth rinses, and tray systems. Oxalates are particularly unique, because unlike other compounds that occlude the dentinal tubules, oxalates are insoluble in acids and remain intact when exposed to mechanical challenges such as brushing, dietary acids, and salivation.¹ Altuve and colleagues reported that research indicated polyethylene strips coated with a 1.5% oxalate gel offered quick and longer-lasting relief for hypersensitive teeth compared to some toothpastes containing potassium nitrate.¹ 

There are some prescription-strength dentifrices and varnishes that contain amorphous calcium phosphate (ACP), casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), calcium sodium phosphosilicate, and tricalcium phosphate (TCP) that can be used to treat DH. ACP and calcium sodium phosphosilicate help to reduce sensitivity by accelerating remineralization, while CPP-ACP works to partially occlude the dentinal tubules.³ TCP, the newest member of the calcium phosphate family, decreases sensitivity by enhancing remineralization through the slow release of calcium to the tooth surface.³ 

When recommending a dentifrice or mouth rinse to treat DH, it is important to educate the patient on proper usage of these products to achieve the desired result, since the effectiveness of these products relies heavily on patient compliance. Patients can expect to experience relief with these products within two to four weeks, but they must be used consistently. It is also worth noting that patients should be cautioned to use a minimal amount of water with these treatment options to prevent dilution of the active agent. 

Patients may have to consider in-office treatment therapies when at-home agents are ineffective. These in-office therapies include the use of paint-on desensitizing agents, which can often provide immediate relief. It is not uncommon for DHCP to recommend patients follow up with an at-home desensitizing agent after receiving this type of treatment to achieve longer-lasting results. Strassler and colleagues reported that the use of 5% glutaraldehyde and 35% hydroxyethylmethacrylate is highly effective in providing DH relief for up to nine months, and although very little research exists to support the use of steroids as a treatment option, using 0.5% or 1% prednisolone on the exposed root surface can provide cessation of sensitivity immediately after application.⁶ First used in the 1960s, iontophoresis continues to be used to provide temporary relief from DH. Iontophoresis uses a low galvanic current along with fluoride gels to cause movement of metal ions, thereby producing an electric current, which results in the precipitation of insoluble calcium to occlude open tubules.^6,8 Hypersensitive teeth that have been exposed due to recession and have root surface loss as a result of abrasion, erosion, and/or an abfraction leaving a notching of the root may require the placement of an adhesive composite resin or glass ionomer restoration to cover the exposed surface to provide DH relief or grafting.⁶

Lasers are also an effective in-office therapy used to seal dentinal tubules. The use of the Nd:YAG, Er:YAG, and He-Ne laser have been found to be successful for providing DH relief.^3,6 

Admira Protect and Remin Pro

In addition to Profluorid Varnish and Profluorid L, as we discussed in part one of this article series, Voco also offers two additional products to help provide DH relief: Admira Protect and Remin Pro. Admira Protect (AP) is an innovative ORMOCER-based light-curing protective varnish desensitizer that is biocompatible and uses special filler technology and fluoride release to provide long-term elimination of hypersensitivity.⁹ AP works to eliminate DH through the precipitation of plasma proteins of dentinal fluid inside the tubules, which offers significant reduction of stimulus transfer through intensive deep sealing of the exposed root dentin and reduced fluid flow.⁹ Studies show that hypersensitivity relief can be achieved up to two years with AP. The special nanofiller technology is designed to provide a highly abrasion-resistant protective layer.⁹ In addition to treating hypersensitive root surfaces, this transparent varnish is ideal for desensitizing crown margins after tooth cleaning and scaling and for exposed cervical areas.¹⁰

Voco’s Remin Pro (RP) tooth cream is also an effective treatment for DH. RP contains nano-hydroxyapatite, which fills superficial enamel lesions and the tiniest irregularities that arise from erosion and restores mineral balance to the tooth.¹¹ RP adheres to the tooth substance and protects the tooth against demineralization and erosion. With RP, natural remineralization is simultaneously promoted, thereby offering additional protection for the tooth. RP also contains fluoride, which seals the open dentinal tubules, and xylitol, which gives RP bacteriostatic and cariostatic properties as well.¹¹ RP is free of sodium lauryl sulfate and triclosan, has a neutral pH, is void of milk protein, is easy to apply, and comes in three great-tasting flavors.

Clinical management of DH should be based on etiology and severity. Depending on the severity, clinical management may involve both at-home and in-office therapies. A combination of both may be necessary to provide long-term relief. It is wise to recommend the most cost-effective treatment as a first line of defense, which is often a desensitizing toothpaste. The effectiveness of products relies on the delivery system, ingredient, formulation, and patient compliance.⁶ Once a tooth becomes hypersensitive, it should be reevaluated at each appointment with an emphasis on prevention of the condition. 

Editor's note: This article is sponsored by Voco. Content has been reviewed for editorial integrity per RDH guidelines. For more information on our editorial standards, see rdhmag.com/page/submission-guidelines.

References

1. Altuvue A, Sagel PA, Gerlach RW. Innovations in dentin hypersensitivity: a unique oxalate-based strip technology. Aegis Dental Network. May 2016. https://www.aegisdentalnetwork.com/cced/special-issues/2016/05/innovations-in-dentin-hypersensitivity-a-unique-oxalate-based-strip-technology
2. Davari A, Ataei E, Assarzadeh H. Dentin hypersensitivity: etiology, diagnosis and treatment; a literature review. J Dent (Shiraz). 2013;14(3):136-145.
3. Trushkowsky RD. Etiology and treatment of dentinal hypersensitivity. Decis Dent. December 8, 2016. https://decisionsindentistry.com/article/etiology-treatment-dentinal-hypersensativity/
4. Anderson CJ, Kugel G, Zou Y, Ferrari M, Gerlach R. A randomized, controlled, two-month pilot trial of stannous fluoride dentifrice versus sodium fluoride dentifrice after oxalate treatment for dentinal hypersensitivity. Clin Oral Investig. 2020;24(11):4043-4049. doi:10.1007/s00784-020-03275-8
5. Miglani S, Aggarwal V, Ahuja B. Dentin hypersensitivity: recent trends in management. J Conserv Dent. 2010;13(4):218-224. doi:10.4103/0972-0707.73385
6. Strassler HE. Dentinal hypersensitivity: dilemmas and treatment. American Dental Assistants Association. April 2019. https://adaa.cdeworld.com/courses/21338-dentinal-hypersensitivity-dilemmas-and-treatment
7. da Cruz LPD, Hill RG, Chen X, Gillam DG. Dentine tubule occlusion by novel bioactive glass-based toothpastes. Int J Dent. 2018;2018:5701638. doi:10.1155/2018/5701638
8. Patil AR, Varma S, Suragimath G, Abbayya K, Zope SA, Kale V. Comparative evaluation of efficacy of iontophoresis with 0.33% sodium fluoride gel and diode laser alone on occlusion of dentinal tubules. J Clin Diagn Res. 2017;11(8):ZC123-ZC126. doi:10.7860/JCDR/2017/29428.10526
9. Admira Protect overview. Voco. https://www.voco.dental/in/products/oral-care/desensitizer/admira-protect.aspx
10. Admira Protect: Light-curing ORMOCER-based protective desensitizer. Voco. https://www.voco.dental/us/portaldata/1/resources/products/folders/gb/admira-protect_fol_gb.pdf
11. Remin Pro. Voco. https://www.voco.dental/us/products/preventive-care/protective-dental-care/remin-pro-not-available-in-canada.aspx