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A Fresh Look at Dental Sealants

The effects of COVID-19 on the role of sealants in caries prevention.

While the urgency of the COVID-19 pandemic has waned, its wake leaves the extraordinary challenges it posed in clear view.1 The delivery of healthcare, including dental care, was profoundly impacted around the globe.2

The pandemic highlighted the potential risks of dental aerosols. Many oral healthcare procedures generate aerosols, which are deemed aerosol-generating procedures (AGP).3 Preventive and restorative dental procedures require the use of instruments that create AGP. Air-water syringes, high-speed handpieces, air polishers, and ultrasonic scalers all produce aerosols in the dental setting.4 AGP are considered a significant risk for the aerosol transmission of many infectious diseases.5,6 Aerosols produced within the dental setting pose a great risk to oral health professionals and their patients. Delivery of dental care involves close interpersonal contact between patients and clinicians, increasing the risk of transmission of infectious diseases, such as COVID-19.1,7–11

At the onset and the height of the COVID-19 outbreak, the United States Centers for Disease Control and Prevention (CDC) initially recommended that AGP be avoided and only used for emergency dental care.12 However, the CDC has since updated its guidelines indicating AGP may be used on patients who are not suspected or confirmed of having COVID-19.13 Preventing disease transmission within the dental setting weighs heavily on oral health professionals. As such, clinicians are obligated to manage dental procedures in a safe and effective manner. Wearing appropriate personal protective equipment and using dental air purifiers are strategies to reduce aerosol exposure.14

While most patients have returned to the operatory, the pandemic increased already present disparities in access to care for the most vulnerable populations. Access to dental care has been a long-time concern, and the COVID-19 pandemic has created additional barriers.2,15

Caries Prevalence

Dental caries is one of the most common chronic diseases affecting children in the US as well as globally. Statistics indicate more than 530 million children worldwide have untreated caries in primary teeth, with the prevalence increasing with age.16 The National Institute of Dental and Craniofacial Research reports a minimum of one out of every six children ages 6 to 11 experience dental caries in their permanent teeth.16 Additionally, more than half of adolescents, ages 12 to 19 have dental caries in their permanent teeth.16 These numbers will likely increase due to the pandemic-induced closure of dental offices for 6 months, loss of insurance benefits, financial hardship, and concerns related to contracting COVID-19.17

Patient education and preventive interventions are needed to reduce the pandemic’s impact on the incidence of dental caries and potential dental emergencies. Healthcare agencies, such as WHO, have identified caries in children as a major public health problem.16 The COVID-19 pandemic has created an additional burden by limiting access to dental care and increasing the risk of dental caries.

Dental sealants play an important role in caries prevention. Preventive sealing is defined as “the application of a thin physical barrier over a clinically sound caries predilection site, in order to prevent the initiation of a caries lesion.”18 Sealants can be applied to pits, fissures, and fossae in primary and permanent teeth.19

Sealants are a noninvasive, cost-effective, and convenient method of preventing or arresting caries. Once applied, sealants can protect against 80% of carious lesions for 2 years and continue to protect against 50% of carious lesions for up to 4 years.20 Placing sealants on newly erupted teeth and surfaces with deep pits, fissures, and fossae can prevent the need for extensive and expensive restorative treatments.19–21 Unfortunately, even with years of clinical research supporting their efficacy and the availability of clinical practice guidelines, sealants are underutilized in dentistry. As a result, clinicians need to thoroughly explain and recommend sealants as a preventive treatment option. The sealant materials most commonly used in clinical practice are resin-based sealants (RBS) and glass ionomer (GI).21

Resin-Based Sealants

RBS are effective in preventing caries, however, they are technique sensitive and most (but not all) products require a dry field during application to ensure proper retention and longevity.22 The caries-preventive effect of RBS relies on the sealing of pits and fissures through microretention, created through tags after enamel etching.23

Various types of conventional RBS have been introduced over the years such as light-cured, self-cured, translucent and tinted, filled and unfilled, high and low viscosities, and fluoride releasing, all of which remain technique sensitive.21,22 In recent years, hydrophilic RBS materials have been developed to work in a moist field. These increase the material’s flowability, making the sealant less vulnerable to retention failure. When comparing retention and caries prevention of hydrophobic (conventional) RBS to hydrophilic RBS, no statistically significant difference was found.22

Glass Ionomer Sealants

GI sealants work by physically blocking the pits and fissures through the production of effective adhesion, without the use of acid etch.21 GI sealant placement is not an AGP, as it doesn’t require rinsing. GI sealants contain fluoride that can help to prevent caries through their release over a prolonged period.24 The preventive effect may last after the sealant material is lost, as some parts of the material may remain deep in the fissures.19 Notably, GI is hydrophilic and can be applied in a wet field, which makes it compatible with the challenging environment of the oral cavity. Moreover, since isolation is not necessary, GI sealants are simple to apply on small children, patients with special needs, or those who are noncooperative.25

Recommendations for Sealant Placement in a High-Risk Environment

During the COVID-19 pandemic and beyond, prevention should be emphasized over surgical interventions. The pandemic has heightened awareness regarding access to care, which has led to additional efforts to promote prevention. Oral health professionals should concentrate on implementing nonaerosolizing caries prevention and management techniques—such as sealants—to improve oral health outcomes among vulnerable populations.2

Retention rates are slightly higher for RBS than GI over a 4-year period and both materials exhibit significant caries preventive effects.2 However, studies have not demonstrated that one sealant material is superior to the other.26,27 As such, selection of the appropriate material should be based on the patient and surrounding circumstances. Use of clinical judgment will help guide clinicians in determining which sealant material and application technique work best in the current situation (eg, a pandemic, uncooperative child, or excessive saliva).

RBS placement involves rinsing to thoroughly remove the acid etch, which generates some aerosol.28 In order to reduce the risk of SARS-CoV-2 transmission, the use of a GI sealant, which does not require rinsing, may be prudent in high-risk settings.28


The COVID-19 pandemic has presented many obstacles in the dental field, but also opportunities to review the management of AGP. New innovations to reduce aerosols and ensure clinician and patient safety continue to be introduced.16 Amid the COVID-19 pandemic, oral healthcare providers and advocates must clearly communicate the importance of oral health to overall health, indicate the steps being taken to ensure patient and provider safety, and promote prevention and nonaerosolizing procedures.2 Placing sealants is an effective caries-prevention strategy that should be recommended for those susceptible to caries.


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  11. Cleveland JL, Gray SK, Harte JA, Robison VA, Moorman AC, Gooch BF. Transmission of blood-borne pathogens in US dental health care settings: 2016 update. J Am Dent Assoc. 2016;147:729–738.
  12. United States Centers for Disease Control and Prevention. Coronavirus Disease 2019 (COVID-19). Available at: Accessed October 19, 2022.
  13. United States Centers for Disease Control and Prevention. Interim Infection Prevention and Control Recommendations for Healthcare Personnel During the Coronavirus Disease 2019 (COVID-19) Pandemic. Available at: Accessed October 19, 2022.
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  15. World Health Organization. Oral Health. Available at:,%25%20in%20high%2Dincome%20countries. Accessed October 19, 2022.
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  22. Alsabek L, Al-Nerabieah Z, Bshara N, Comisi JC. Retention and remineralization effect of moisture tolerant resin-based sealant and glass ionomer sealant on non-cavitated pit and fissure caries: randomized controlled clinical trial. J Dent. 2019;86:69–74.
  23. Mickenautsch S, Yengopal V. Caries-preventive effect of glass ionomer and resin-based fissure sealants on permanent teeth: an update of systematic review evidence. BMC Res Notes. 2011;4:22.
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  25. Eskandarian T, Baghi S, Alipoor A. Comparison of clinical success of applying a kind of fissure sealant on the lower permanent molar teeth in dry and wet conditions. J Dent (Shiraz). 2015;16:162–168.
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From Dimensions of Dental Hygiene. November/December 2022;20(11)16,18,.

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