Introduction:
With multiple findings and research still in process, the manifestations of COVID are also seen in the oral cavity beyond the basic respiratory troubles it is usually characterized by. According to a study by the National Institute of Health (NIH), nearly half the victims of COVID suffer from oral symptoms during the course of infection.
What Are the Dental Concerns and Etiology of COVID-19?
Following the hiatus brought on by the COVID-19 pandemic, dental professionals are seeing an increase in the oral manifestations that are viral in origin that may be potentially associated with Coronavirus infections. Though there is no mention of oral symptoms listed either by the US center for disease control and prevention or the WHO, the most common issues other than fever, dry cough, and tiredness are loss of taste or smell (ageusia and anosmia], sore throat, and nasal congestion according to WHO.
Studies suggest that the COVID survivors now report oral problems like tongue oddities (bumps or inflammation of the tongue), sensitive gums, cracked teeth, loss of taste or ageusia, dry mouth, oral ulcerations, and even enlargement of the submandibular and cervical lymph nodes of the neck.
Studies suggest that the mouth is a vulnerable area for coronavirus because of an abundance of ACE-2 (Angiotensin Converting enzymes) receptors in the oral tissues. The SARS-CoV-2 virus mainly targets these receptors and replicates in these areas, increasing the concentration in specific oral tissues like the tongue, causing COVID tongue. But in general, as a wide range of other viruses that affect oral structures are also causative agents of oral manifestations and lesions, the differential diagnosis is difficult to be established in asymptomatic patients. The herpes zoster virus, varicella-zoster virus, coxsackievirus, and HPV virus are other viruses that affect the oral cavity and cause the same symptoms and oral manifestations.
As the discernment of COVID-19 manifestations orally is still a work in progress by researchers and dental professionals, according to literature, the common signs and symptoms to watch out for are presented below:
1. Dysgeusia and Ageusia (Altered Taste and Loss of Taste):
In the presymptomatic or asymptomatic COVID cases, altered taste sensation or dysgeusia is considered the first consequence of SARS-CoV-2 infection. Dysgeusia may accompany with or without anosmia (loss of sense of smell) and appears to affect older adults more than young adults and women more often than men. Anosmia or loss of sense of smell is frequently accompanied by loss of taste or ageusia. These symptoms are important for detecting COVID infections in asymptomatic or presymptomatic cases.
2. Sialadenitis:
The literature identifies salivary gland inflammation and enlargement cases termed as sialadenitis that involves the infection of the parotid or the submandibular glands (salivary glands of the mouth) in COVID-19 patients. The salivary glands are present in front of the ear or the chin area. Pain, tenderness, and localized swelling or redness of the affected area are symptoms of sialadenitis.
3. Xerostomia:
Also commonly known as dry mouth syndrome or hyposalivation (decreased or less saliva) leading to mouth dryness, it is another symptom of sialadenitis and not a very observable or obvious sign in many cases. Most often, it is an additional oral symptom in COVID patients. As the quantity and the quality of saliva produced are impacted, Xerostomia, in turn, is linked to an increase in candida infections (thrush) or dental caries. Dry mouth can also be generally caused by mouth breathing, side effects of certain medications, dehydration, or anxiety.
4. Inadequate Vitamin D Levels Causing Dental Issues:
Patients with COVID-19 may have inadequate vitamin D levels in their blood, and vitamin D is essential for healthy bone, teeth, and muscle formation, renewal, and development. Sensitive teeth, tooth fractures, or cracked teeth would also be due to grinding or clenching habits and multiple stressors apart from this reason. COVID-19 cases with adequate vitamin D levels tend towards a favorable prognosis.
5. Oral Ulcerative Lesions and Gingival Tissue Breakdown:
The vascular abnormalities lead to damage of ACE-2 receptors orally, and oxygen deprivation leads to tissue necrosis or death of oral tissue cells or gingival tissue. This manifests as ulcerative or gingival lesions akin to any other oral infection of viral origin. Research is being done on the possibility of periodontal disease (gum disease) contributing to the severity of COVID-19 infection.
What Is the Impact of COVID-19 Treatment on the Oral Cavity?
Out of the various new therapies, antiviral therapies by Interferon (IFN) alpha or beta are commonly used to treat the novel Coronavirus reduces the severity of the disease, potentially improving survival rates. IFN alpha or beta therapies also significantly help lower COVID-related pneumonia and support increased lung function capacity. The use of IFN in COVID treatment is linked to side effects in the oral cavity like xerostomia (dry mouth) and oral thrush.
Research shows SARS-CoV-2 also causes a cytokine storm that aggravates existing autoimmune conditions in the oropharyngeal area leading to oral symptoms. Besides using antiviral drugs in COVID treatment, increased angiotensin II levels, as mentioned earlier (ACE-2 receptors to which Coronavirus binds), causes vascular abnormalities, vasoconstriction, and increased vascular permeability in the oral tissues leading to oral ulceration. Improper oral care and pre-existing oral diseases that the dentist has not treated during the pandemic (as dental treatment is not prioritized or ignored by some patients) is another major factor for the pathologies affecting oral mucosa and the changes in the salivary gland functions.
Saliva Test:
Saliva has the ability to harbor infectious organisms; hence, it is a valuable biomarker for early detection and can be used as an alternative test for the presence of coronavirus. The saliva test is less invasive and nearly as accurate as nasal and throat swabs for COVID-19.
How Are COVID Oral Lesions Treated?
Treatment of oral lesions by COVID and COVID tongue is best rendered by your dental surgeon via biopsy and DNA analysis from swab or saliva test diagnosis. Antifungal oral medications, essential oils, and complementation of vitamins expedite recovery in COVID cases. The occurrence of SARS COV-2 pathogen orally is hence an immense public health concern apart from being a diagnostic challenge to dental practitioners as it manifests the oral symptoms caused by other viral origins.
Conclusion:
Dental professionals should be aware of the potential manifestations of COVID-19 on the oral cavity and follow stringent infection control procedures while examining the patient intraorally and extra orally. Irrespective of the etiology of the viral infections affecting the mouth, be observant and cautious of the manifestations commonly reported by COVID patients by checking your oral cavity. Get an opinion from your dental surgeon by telephonic conversations or online consultation if you suspect a COVID manifestation orally.
