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Crystals of carbamide, also known as urea. Carbamide peroxide is composed of equal parts of carbamide and hydrogen peroxide.
Crystals of carbamide, also known as urea. Carbamide peroxide is composed of equal parts of carbamide and hydrogen peroxide.
Crystals of carbamide, also known as urea. Carbamide peroxide is composed of equal parts of carbamide and hydrogen peroxide.
Crystals of carbamide, also known as urea. Carbamide peroxide is composed of equal parts of carbamide and hydrogen peroxide.
Crystals of carbamide, also known as urea. Carbamide peroxide is composed of equal parts of carbamide and hydrogen peroxide.

Could 10% carbamide peroxide be considered an adjunctive therapy for risk management of COVID-19?

Sept. 17, 2020
10% carbamide peroxide has been safely and effectively used for whitening and as an adjunctive therapy for periodontal disease and caries prevention. Susan Woodley, RDH, examines the reasons why it could also be used to manage risk for COVID-19 patients.

A new world has emerged with the global introduction and infiltration of the virus known as COVID-19. In this day of high technology and scientific awareness, not knowing how to combat this enemy leaves us in a state of anxiousness and frenzy to find a cure or, at least, risk management strategies.

As dental professionals, much of our patient treatment involves risk management. Given what science reveals about the antiviral and antibacterial properties of hydrogen peroxide combined with inductive reasoning, is it feasible to consider use of low dose 10% carbamide peroxide to mitigate risk in the fight against this formidable adversary?

Why 10% carbamide peroxide?

Ten percent carbamide peroxide is used in the most widely researched formulation of whitening gels and as an adjunctive therapy for periodontal disease and caries prevention. It breaks down to 6.5% urea and 3.5% hydrogen peroxide (H₂0₂).1 The urea works first to raise the pH level to an average peak value of 7.32/± 0.27 after 15 minutes from insertion.2 The oxidizing power of H₂0₂ is directly involved in the inactivation of viruses and bacteria.3 The liberation of oxygen into the gingival crevice changes the bacterial environment to remove the gram-negative bacteria, cleanse the pocket, and stimulate healing.4 Hydrogen peroxide is a very powerful oxidizing agent that is capable of reaching deep periodontal pockets, even against gingival crevicular fluid pressure, when used in a customized therapeutic tray.5 Using 10% carbamide peroxide in therapeutic trays that are nonscalloped and trimmed 2 mm from the gingival margins also creates an anticariogenic environment. Reducing the risk for caries that can lead to infection and inflammation further contributes to risk management for minimizing inflammation.

There is good evidence for safe daily use of hydrogen peroxide at low concentrations over long periods.6 Therefore, using inductive reasoning, treatment planning low-dose 10% carbamide peroxide daily for six weeks followed with a maintenance routine of twice weekly may raise the level of protection for patients with periodontal disease by reducing their level of inflammation. According to Drs. Joseph Greenwell-Cohen and Linda Greenwell, plaque accumulation, dental caries, and periodontal disease are an increasing concern, especially for elderly, special care, and orthodontic patients.7 This is due in large part to numerous predisposing factors that make maintenance of adequate oral hygiene difficult. We know oral hygiene and plaque control are essential to the prevention of oral disease; however, traditional oral hygiene methods may not always be sufficient. The use of a custom or boil-and-form tray containing carbamide peroxide may provide clinicians and patients with a simple, safe, and effective method for improving patients’ oral hygiene and oral health when traditional methods are unsatisfactory. The application method requires little manual dexterity, which is beneficial for elderly and special care patients. Traditional oral hygiene practice is still essential and must be emphasized to the patient.7

What do we know about COVID-19 patients?

We know those who are at increased risk of contracting viral/bacterial diseases often have higher levels of inflammation in the body. Introducing methods in which to mitigate elevated levels of inflammation wherever possible may help reduce the risk of contracting these diseases. “Inflammation is a vital part of the immune system’s response to injury and infection. It is the body’s way of signaling the immune system to heal and repair damaged tissue, as well as defend itself against foreign invaders, such as viruses and bacteria.”8

According to award-winning British dentist Dr. Victoria Sampson, oral hygiene should be improved during a COVID-19 infection to reduce the bacterial load in the mouth and the risk of a bacterial superinfection.9 It is recommended that poor oral hygiene be considered a risk for COVID-19 complications, particularly in patients predisposed to altered biofilms due to diabetes, hypertension, or cardiovascular disease. Bacteria present in patients with severe COVID-19 are associated with the oral cavity, and improved oral hygiene may reduce the risk of complications. While COVID-19 has a viral origin, it is suspected that in severe forms of the infection, bacteria plays a part, increasing the chance of complications such as pneumonia, acute respiratory distress syndrome, sepsis, septic shock, and death.9

A recent study conducted by Molayem and Pontes suggests a link between gum disease and respiratory failure in COVID-19 patients.10 Coronavirus patients who have been hospitalized are far more likely to die of respiratory failure if they suffered from periodontitis before contracting COVID-19, according to an international team of dental researchers. What shocked us was the discovery of the protein’s (Interlueken-6) devastating, life-threatening impact to patients once they’re hospitalized. One tiny, inflammatory protein robbed them of their ability to breathe,” said Molayem.10

The researchers determined that hospitalized COVID-19 patients with periodontitis IL-6 levels above 80 pg/ml are 22 times more likely to suffer from acute respiratory problems and placed on a ventilator, compared to patients with IL-6 levels below 80 pg/ml. According to the researchers, COVID-19 patients who suffer respiratory failure face grim odds for recovery, with almost 80% of those placed on ventilators in the United States since the beginning of the pandemic dying. Elderly patients are more likely to suffer from chronic gum disease than any other age group, the researchers added, and this demographic face significant risks from COVID-19 as well.10,11

The model of the “typical” patient with COVID-19 has changed dramatically over the past few months. The “high risk individuals” who are older and/or have comorbidities are still considered to be more susceptible to this virus. However, as we learn more about COVID-19 and its robust nature, we now see patients from all ages who are falling victim to this debilitating virus.

Something to contemplate

With this emerging science, dentistry has an opportunity to play a vital role in the fight against COVID-19 and its potentially devastating outcomes linked to periodontitis.

H₂O₂ has an extensive history for safe and effective use in the mouth as an antibacterial agent since first documented in 1913. Combined with what we now know, could 10% carbamide peroxide be used to aid in the fight against COVID-19 and its debilitating and potentially fatal outcomes? Admittedly, more research is needed in this area, but I believe it is an opportunity worth exploring.

References

1. Haywood VB.  Bleaching and caries control in the elderly. Dent Econ. Jan. 1, 2010. https://www.dentaleconomics.com/science-tech/article/16392777/bleaching-and-caries-control-in-the-elderly

2. Leonard RH Jr, Bentley CD, Haywood VB. Salivary pH changes during 10% carbamide peroxide bleaching. Quintessence Int. 1994;25(8):547-550. https://www.ncbi.nlm.nih.gov/pubmed/7568702

3. Asghari A. The inactivation of bacteria and viruses by hydrogen peroxide. Dissertation. University of Florida. 1993. https://ufdcimages.uflib.ufl.edu/AA/00/06/47/39/00001/AA00064739_00001.pdf

4. Greenwall L. Therapeutic aesthetics. ADT. May 2014. https://static1.squarespace.com/static/5dc43d56f1a40f72ec167c68/t/5e2c1d11e2129124f00feb55/1579949337842/ADT+May+Greenwall+Clin.pd

5. Bosecker J. Tray delivery helps hydrogen peroxide deliver its punch to biofilm. RDH magazine. Jun. 5, 2013. https://www.rdhmag.com/patient-care/prosthodontics/article/16406376/hydrogen-peroxide-in-dentistry.

6. Walsh LJ. Safety issues relating to the use of hydrogen peroxide in dentistry. Aust Dent J. 2000;45:257-269. doi:10.1111/j.1834-7819.2000.tb00261.x

7. Greenwall-Cohen J, Greenwall L. Carbamide peroxide and its use in oral hygiene and health. Dent Update. 2017;44:863-869. 

8. Szalay J. What is inflammation? Livescience. Oct. 19, 2018. https://www.livescience.com/52344-inflammation.html

9. World Health Organization. Clinical management of COVID-19. May 27, 2020.  https://www.who.int/publications-detail/clinical-management-of-severe-acute-respiratory-infection-when-novel-coronavirus-(ncov)-infection-is-suspected

10. Molayem S, Pontes CC. The mouth-COVID connection: I1-6 levels in periodontal disease—potential role in COVID-19-related respiratory complications. J Calif Dent Assoc. Published online ahead of print Jul. 30, 2020.

11. COVID-19 patients with periodontitis face greater risk of dying. Dent Today. Aug. 10, 2020. https://www.dentistrytoday.com/news/industrynews/item/6778-covid-19-patients-with-periodontitis-face-greater-risk-of-dying

SUSAN WOODLEY, RDH, is a registered dental hygienist and practice consultant for dental clinics across Canada. Throughout her career in dental hygiene, Susan has worked in general, orthodontic, and pediatric practices. In her previous role as manager of professional education for Philips Oral Healthcare North America, she provided continuing education courses to dental professionals as well as educational programs to dental, dental hygiene, and dental assisting students across western Canada. Susan is a published author and former part-time professor of dental hygiene and dental assisting programs. She and her husband now reside in Kelowna, BC.