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 Table of Contents  
EDITORIAL
Year : 2021  |  Volume : 2  |  Issue : 3  |  Page : 57-61

A comprehensive insights into oral health in COVID-19


1 Rungta College of Dental Sciences and Research, Bhilai, Chhattisgarh, India
2 Mahatma Gandhi Post Graduate Institute of Dental Sciences, Puducherry, India
3 Dr. NTR University of Health Sciences, Vijayawada, Andhra Pradesh, India

Date of Submission08-May-2021
Date of Decision16-Jun-2021
Date of Acceptance26-Jun-2021
Date of Web Publication25-Aug-2021

Correspondence Address:
Tarun Kumar Suvvari
Dr. NTR University of Health Sciences, Vijayawada, Andhra Pradesh
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jpcdoh.jpcdoh_16_21

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  Abstract 


The novel coronavirus 2019 (COVID-19) is a highly contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and the most probable route of entrance for the SARS-CoV-2 virus is suggested to be that of oral mucosa as it contains angiotensin-converting enzyme 2 receptors, which acts as a cellular doorway for the entry of the virus. Anti-viral and broad-spectrum antibiotics used to treat COVID-19 can be responsible for oral problems associated with soft tissue, saliva production, and neurological-based oral sensations reported even in fully recovered patients. Oral manifestations like loss of taste (complete ageusia or partial hypogeusia) and altered taste were most common, followed by various lesions and plaques affecting the intraoral site. Poor oral hygiene can lead to complications in patients suffering from systemic diseases such as diabetes, kidney, and liver disease. Since oral health has a significant impact on a patient's general health, improved oral hygiene can significantly decrease the risk of oropharyngeal colonization and respiratory complications, especially in the elderly and patients admitted to the intensive care unit. Due to the high risk of COVID-19 transmission among dentists and patients, it is important to re-design recommendations to oral medicine and dentists working in the hospital setting to manage oral manifestations. Oral health-related quality of life is an all-encompassing term used to denote how one's oral health impacts on their ability to function normally can be a crucial subjective measure to analyze oral health during these challenging times.

Keywords: COVID-19, dental, oral health, oral lesions, severe acute respiratory syndrome coronavirus 2


How to cite this article:
Sree P C, Sunantha S P, Suvvari TK. A comprehensive insights into oral health in COVID-19. J Prim Care Dent Oral Health 2021;2:57-61

How to cite this URL:
Sree P C, Sunantha S P, Suvvari TK. A comprehensive insights into oral health in COVID-19. J Prim Care Dent Oral Health [serial online] 2021 [cited 2021 Oct 24];2:57-61. Available from: http://www.jpcdoh.org/text.asp?2021/2/3/57/324536




  Introduction Top


The novel coronavirus 2019 (COVID-19) is a highly contagious disease that has not been previously identified in humans. It is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) belonging to the genus β-coronavirus and family coronaviridae.[1] SARS-CoV-2 is an enveloped, single-stranded positive-sense RNA virus with an incubation period of this disease that varies from 1 to 14 days.[1] The SARS-CoV-2 can infect people of all ages, and older people, people with preexisting medical conditions like asthma, diabetes, heart disease appear to be more vulnerable to COVID-19. The most commonly reported clinical symptoms are fever, dry cough, headache, dyspnea, myalgia, respiratory distress, renal impairment, diarrhea.[1] Severe COVID-19 can cause cytokine storms, followed by acute respiratory distress syndrome and multiple organ failure and finally leading to death.[1]


  The Impact of COVID-19 on Oral Health Top


The most probable route of entrance for the SARS-CoV-2 virus is suggested to be that of the oral mucosa. Angiotensin-converting enzyme 2 (ACE-2) receptors present on various oral mucosal tissues act as cellular doorways for the entry of the virus.[2] The spike-like protein on the surface of the SARS-CoV-2 virus binds to the receptor present mainly in the tongue, floor of the mouth, and buccal and gingival epithelial cells. Lymphocytopenia, overactivation of T-cells cause an elevation in Th17 and cytotoxicity of CD8 T cells.[3] Factors like these decrease the cellular/humoral immune response and subject even the healthiest individuals to be vulnerable to serious complications, especially in the lower respiratory tract region.[3] Direct effects of COVID-19 include the first official symptom, ageusia. This symptom is transient but is reported in most of the patients.[2] One of the possible reasons for this to be an initial infection site could be that 96% of oral ACE2 receptor cells are present on the tongue. The SARS-CoV-2 virus can be identified in the whole saliva in the initial stage of the viral entry and can even be detected in the saliva taken up from the ductal opening of salivary glands. In other primates, the salivary gland function can be amiss starting from the initial stage of the disease.[2] The direct effects of COVID 19 are considered to be of modest consequence in relation to population oral health.[4]

Although the benefits outweigh the side effects of drugs used for the treatment of COVID-19, they can still be taken under consideration for the oral problems associated with soft tissue, saliva production, neurological-based oral sensations, etc., seen even in fully recovered COVID-19 patients.[3] Anti-viral drugs including Lopinavir, Ritonavir, and other protease inhibitors used as a treatment option for HIV can produce side effects in the oral cavity, including stomatitis, ulcers, and dry mouth but are also responsible for the effects in the gastrointestinal tract. Anti-viral activity of interferon-alpha/beta used for reducing symptoms of severe respiratory illness, including that of COVID-19 related pneumonia, can be responsible for dry mouth, which leads to oral thrush in many cases.[3] Broad-spectrum antibiotics such as meropenem or moxifloxacin used in critically ill COVID-19 patients disbalance the harmony between microorganisms of oral flora, leading to further complications. Systemic and topical steroids used for immune-related oral diseases such as pemphigus, pemphigoid, and lichen planus are discouraged in COVID-19 patients as they are said to be exaggerating the symptoms. On the other hand, anti-inflammatory medicines used for patients with oral conditions having co-existing comorbidities like Sjogren's syndrome are encouraged as they are said to protect against COVID-19 complications.[3] Chloroquine, an amino quinolone derivative used majorly for the treatment of malaria and tocilizumab, an immunosuppressive monoclonal antibody targeting the IL-6 receptors mainly used for autoimmune disorders, are advised for the treatment of critically ill COVID-19 patients, can also be considered responsible for oral manifestations.

Oral health is compromised in severely ill hospitalized patients due to external ventilation, intubation, tracheostomy, and blood oxygenation, especially required in respiratory intensive care units. This, along with lack of oral care as a treatment priority, can lead to hyposalivation, which can be accountable for complications in the oral cavity and lower respiratory tract.[3] Restricted access to oral health care studied using Anderson's model of health service use (2014) focusing on the interactions between people, healthcare systems, and external environment can state the multi-directional, indirect effects of COVID-19 are said to be more complex and extensive.[4]


  Oral Manifestations of COVID-19 Top


Oral manifestations affect the keratinized as well as the nonkeratinized mucosa.[5] The most commonly affected intraoral site was the hard palate, followed by the dorsum of the tongue and labial mucosa. The diagnosis was based on clinical features and biopsies of some of the common orofacial features.[6] The data found in the literature are limited to a few case reports. The mean age is approximately 52 years. The observed lesions were heterogeneous, varying in type and location of the lesion,[7] according to a cross-sectional study on 666 patients in a field hospital in Spain with inclusion criteria of either positive reverse transcription-polymerase chain reaction testing for SARS-CoV-2 or bilateral pneumonia, 25.7% patients presented with oral cavity findings including transient lingual papillitis (11.5%), glossitis with lateral indentations (6.6%), aphthous stomatitis (6.9%), glossitis with patchy depapillation (3.9%), and mucositis (3.9%). Other commonly reported symptoms included burning sensation and taste disturbances.[8] According to another study, the prevalence of olfactory disturbances ranged from 68% to 85%, while that of taste disturbances, including the loss of taste (complete ageusia or partial hypogeusia) and altered taste (dysgeusia), ranged from 71% to 88.8% if dysgeusia is considered a prognostic marker for the severity of COVID-19 after SARS-COV-2 infection is still under study.[9]

Some common hypothesis regarding the potential mechanisms by which taste dysfunction develops in SARS-COV-2 infection are:

  • Dysfunction of ACE2 receptors found in the epithelium of salivary glands results in impairment of salivary flow in both quality and quantity, leading to dysgeusia
  • Since gustatory and olfactory functions are interlinked, damage to nonneuronal cells present in olfactory epithelium can result in taste disturbances
  • This can be due to direct damage of either the ACE2 expressing cells found in taste buds and peripheral taste neurosensory chemoreceptors or one of the cranial nerves accountable for gustation (CN VII, XI or X)
  • ACE2 receptors present in oral mucosa triggering an inflammatory response pathway leading to cellular and genetic changes, which ultimately cause taste dysfunction
  • Since anemia and poor oxygen transport can cause taste disturbances; tissue hypoxia due to tissue injury can be considered a possible mechanism.


Few randomized controlled trials have shown improvement in COVID-19 patients undergoing zinc supplementation; hence zinc chelation due to immune mechanisms leading to acute hypozincemia or change in zinc homeostasis of oral gustatory cells can be considered a possible explanation of taste dysfunction.[9] Other oral manifestations included lesions like aphthous, erythema multiforme, angina bullosa, herpetiform or even nonspecific in nature, ulcers, white and red plaques, necrotizing periodontal disease, vesicles, pustules, petechiae, postinflammatory pigmentation, and diseases including Melkerson Rosenthal syndrome, Atypical sweet syndrome, acute parotitis and Kawasaki like disease.[5] According to a study, 7% of patients reported plaque-like changes in the dorsum of the tongue, while 8% were found to have swelling in their palatal/lingual or buccal/labial area.[5] The characteristic features of the lesions/diseases and clinical profile are described in [Table 1]. Regardless of the treatment employed, a reduction in the oral lesion is seen with a mean time of 7 days.[7]
Table 1: The characteristic features of the lesions/diseases and clinical profile

Click here to view



  Severity of COVID-19 Related to Oral Health Top


Oral health has a significant impact on the general health of a patient. Studies suggest that inflammation seen in distant organs can occur due to cytokines or microbial products released in blood in response to oral infection, leading to the development of systemic diseases, including cardiovascular and cerebrovascular disease. Poor oral hygiene can lead to complications in patients suffering from systemic diseases like diabetes, kidney and liver disease.[10] The oral cavity is a notable reservoir for a respiratory pathogen like Chlamydia pneumoniae, and aspiration of these pathogens may aggravate present lung infection. Salivary enzymes alter mucosal surfaces along the respiratory tract, which help in colonizing respiratory pathogens.[10] Periodontitis can lead to the secretion of pro-inflammatory cytokines, which increase the adhesion of pathogens to the lung epithelium hence help in colonizing the lung.[10]

A study exploring the complication of COVID-19 in patients with poor oral and periodontal disease explains that the infection of gums is one of the most common causes of aspirating bacteria found in the oral cavity.[11] Some of these bacteria include Porphyromonas gingivalis, Fusobacterium nucleatum and Prevotella intermedia.[11] Thus inadequate oral hygiene can lead to interbacterial exchanges between lungs and mouth, leading to postviral bacterial complications.[11] Improved oral hygiene can decrease oropharyngeal colonization and respiratory complications, especially in the elderly population and patients in the intensive care unit. This may decrease the risk of severe COVID-19 symptoms as well morbidity associated with it.[10],[11]


  Therapeutic Challenges and Management of Oral Conditions in COVID-19 Patients Top


Oral health management has been drastically affected during this world wrecking COVID-19 pandemic because of the high risk of COVID-19 transmission among dentists and patients. Hence, it is important to re-design recommendations to oral medicine and dentists working in the hospital setting to manage oral manifestations in SARS-CoV-2 infected individuals.[12]

The infected individuals may develop a variety of oral lesions and due to the pain associated with the lesions, the studies conducted so far aimed to provide support by controlling pain and stimulating wound healing. The whole of the oral cavity was examined COVID 19 affected patients as it cannot be predicted where lesions will develop.[12] Nevertheless, when the oral cavity lesions develop in the context of COVID-19, they tend to affect multiple oral mucosal sites of patients under mechanical ventilation with endotracheal tube.[12] Protocols must be strict and swift, including safety measures to decrease the risk of transmission by reducing contact with the saliva of contaminated patients by the dentist.[12]

The virus has been detected several times in the faeces, suggesting that the orofecal route is also a primary mode of contamination.[13] Periodontal disease may worsen the COVID-19 associated symptoms and routine dental and periodontal treatment could help to decrease the COVID-19 symptoms.[14] Periodontal disease is more prevalent among patients experiencing metabolic diseases such as obesity, diabetes mellitus, cardiovascular diseases as major risk factors, and hypertension has also been mentioned.[14] Periodontal Disease may also be a preexisting condition that worsens COVID-19 outcomes.[14] COVID-19 was found to be highly prevalent in people with halitosis within the dental community, the psychological impacts of COVID-19 are vast.[14]

Published literature revealed cancer patients are at increased risk of COVID-19 infection and a significantly higher risk of mortality over 3.5 times on cancer patients to noncancer individuals.[15] Hence, extra care should be taken while handling the oral treatments of individuals with cancer. The person-to-person spread of COVID-19 disease seems to be rapid and may quickly overwhelm the oral health care settings.[15]

Remdesivir was currently the most investigated and promised anti-viral drug for the treatment of COVID-19 is the anti-viral drug known as remdesivir. Remdesivir acts as an adenosine analog and interferes with viral replication, and inhibits viral synthesis.[14],[15] Other drugs similar to remdesivir include favipiravir and ribavirin. Both of these drugs are guanine analogs that are currently approved for the treatment of other infections but currently no good evidence and support for their use in the treatment of COVID-19. Furthermore, some of the medicines, such as ketoconazole and erythromycin, used for dental treatment may interfere with remdesivir, lopinavir, and hydroxychloroquine.[14] These may intensify COVID-19 symptoms, and dentists should be cautious regarding the drug interactions and follow appropriate treatment to COVID-19 patients with oral problems.[14] Nitric oxide (NO) is a good vasodilator, and Inhaled NO is a potential therapy for pulmonary manifestations.[14] Corticosteroids like dexamethasone and monoclonal antibodies were found to effective against SARS-CoV-2.[16],[17],[18] Dentists should be aware of novel drugs against COVID-19 and their potential side effects. Photobiomodulation therapy can be used in COVID-19 patients with oral ulcerative lesions that don't resolve using conventional therapy.[12]

Toothbrushes play an important role in oral hygiene, but they could be a source for microorganisms and favor COVID-19 transmission. Hence, toothbrush disinfection and hygiene of oral cavity are necessary to control COVID-19 ransmission and the use of mouthwashes could reduce the risk of virus transmission by a great deal.[19]


  Population Studies on Oral Health Top


The geriatric population with multiple comorbidities was a higher risk group for fatal outcomes. Many older populations have been under the medications ACE inhibitors and ARB blockers to manage hypertension, diabetes, and chronic kidney disease. The above medications put the patients at high risk of COVID-19 infection as dentists feel difficult to provide efficient treatment due to more medication contraindication.[20] Many long-term care facilities have transformed into outbreak hot spots for COVID-19 infection because they provide care for older adults with multiple comorbidities.[20] Treating older people with dementia is very hard to follow safely with the best COVID-19 practices. Using facial masks and using preoperative mouth rinses was challenging.[20] Even for community-dwelling older adults, many have hearing and vision problems, communicating following social distance and wearing an N95 mask and full-face shield was challenging.[20] Hence, the treatment of such geriatric patients is very challenging and risky both for themselves and the dentist.


  Pediatric Population Top


General oral health prevention measures

In the COVID-19 pandemic, there is very restricted access to or strongly discouraged nonemergency dental services. Hence, routine dental check-ups and follow-up are tough. We should mainly focus on oral health education and its implementation. We can use digital media and social media platforms and spread behavioral guidelines for oral health care protection in children. Telephone consultations can be a good alternative among all for better outcomes.[21]

Prevention of dental caries

Measures like limiting the intake of fermentable carbohydrates and regular dental floss usage can help prevent carious pathology. As this epidemic forced children to spend most of their time at home, incorrect alimentary habits are bound to develop. Hence, guardians must be well informed about the cariogenic and cardioprotective action of food. Fiber-rich diet not only protects from the onset of caries but its mechanical action leading to salivary secretion also prevents gum diseases. Consumption of soft and sugary drinks should be discouraged since in addition to its high sugar content, their acidity produces dental erosion making the enamel more prone to the attack of cariogenic bacteria.[21] Moreover, stress and anxiety due to home isolation can contribute to an early onset of childhood caries.

Management of children undergoing orthodontic treatment

Since oral cavity has a high expression of ACE2 receptors, appropriate hand hygiene must be maintained before inserting removable orthodontic appliances. For fixed orthodontic appliances such as palatal expander, it is advised to temporarily suspend the activations to avoid unwanted actions, leading to detachment of the device from dental surface.[21] The guardian must make sure their child avoids sticky and vicious foods that can partially detach the appliance, hence triggering an emergency situation requiring interference by a pediatric orthodontist.

Oral health and quality of life

Oral health-related quality of life (OHRQoL) is an all-encompassing term used to denote how one's oral health impacts on their ability to function normally. The concept of OHRQoL is multifactorial and has been defined as “the xtent to which oral disorders affect functioning and psychosocial wellbeing,” ultimately referring to a patient-reported outcome measure.[22] Understanding patient satisfaction through service delivery is of prime importance, as it allows service providers to continually improve their care provision. Evaluating a service from this aspect provides patient-reported experience measures.[23] The pandemic has significantly changed individuals' social and economic aspects, especially of school-going children as they had to switch from classroom sessions to online lectures. Hence, there are worrisome concerns about adolescent's general and oral health as well as psychosocial behavior. OHRQoL can be a crucial subjective measure to analyze oral health during these challenging times.


  Conclusion Top


Therapeutics used in COVID-19 have led to oral problems associated with soft tissue, saliva production, and neurological-based oral sensations. In COVID-19 patients, oral manifestations like loss of taste and altered taste were most common, followed by various lesions and plaques affecting the intraoral site. Poor oral hygiene can lead to complications in patients suffering from systemic diseases like diabetes, kidney and liver disease. Since oral health has a significant impact on a patient's general health, improved oral hygiene can significantly decrease the risk of oropharyngeal colonization and respiratory complications, especially in the elderly and patients admitted to the intensive care unit. Due to the high risk of COVID-19 transmission among dentists and patients, it is important to re-design recommendations to oral medicine and dentists working in the hospital setting to manage oral manifestations.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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