Dental Sealants for Children and Adults: How They Work and Who They Help

Dental sealants are thin protective coatings bonded into the chewing-surface grooves of back teeth to keep plaque and food out of the pits and fissures where many cavities start. They are most often placed on children's permanent molars soon after they come in, and some adults with deep grooves and higher cavity risk are candidates too, after an exam.

Key Takeaways

• Dental sealants protect the pits and fissures of molars and premolars, the surfaces a toothbrush struggles to clean.
• According to the CDC, sealants can prevent up to 80% of cavities for two years and continue to protect against 50% of cavities for up to four years.
• Placement is quick, usually needs no freezing and does not require drilling healthy enamel.
• Sealants can wear or chip, so they are checked at recall visits and repaired when needed; they are not guaranteed for a set number of years.
• Sealants protect grooves only; brushing with fluoride toothpaste, cleaning between teeth and regular checkups are still needed.

What are dental sealants?

A dental sealant is a thin, flowable material, usually a tooth-coloured or clear resin, that is painted into the grooves on the chewing surfaces of back teeth and then hardened. Once set, it forms a smooth barrier over surfaces that would otherwise trap food and bacteria.

The American Dental Association describes sealants as materials that penetrate the pits and fissures of the tooth and form a physical barrier. Two main families are used: resin-based sealants, which are hardened with a curing light, and glass ionomer sealants, which set by chemical reaction and release some fluoride. Your dentist chooses the material according to the tooth, how dry it can be kept and the patient's age.

Sealants are preventive, not restorative. They are placed on teeth that are sound or have only very early, non-cavitated changes in the grooves. A tooth with a cavity that needs a filling is treated differently. At Landmark Dental Care, sealants are part of preventive dentistry, alongside checkups, cleanings and fluoride.

How dental sealants prevent cavities

Back teeth have deep, narrow grooves called pits and fissures. Many are narrower than a single toothbrush bristle, so plaque can sit there even in a child who brushes well. The bacteria in that plaque turn sugars into acid, and the acid begins to dissolve enamel at the bottom of the groove.

A sealant fills and covers the groove, so there is nowhere for plaque to hide and the surface is easier to clean. The evidence is strong for children and teens:

• The CDC states that sealants can prevent up to 80% of cavities for two years and continue to protect against 50% of cavities for up to four years.
• The CDC also reports that school-age children without sealants are almost three times more likely to have cavities in their back teeth than children with sealants.
• An ADA guideline panel found that children and adolescents who received sealants had a 73% lower risk of new cavities than those who received fluoride varnish alone.

Those figures describe groups of patients and depend on the sealant staying in place. Your child's result depends on retention, diet, brushing and the other surfaces of the teeth.

Who may be a candidate for sealants?

Candidacy is decided tooth by tooth at an exam. The dentist looks at groove depth, cavity history, how well the area can be cleaned and whether any decay is already present.

Patient	When sealants are often considered	Main reason
Children about 6 years old	When first permanent molars fully erupt	New enamel, deep grooves, developing brushing skills
Children about 12 years old	When second permanent molars erupt	Same risk window for the next set of molars
Children with baby-tooth decay	Selected primary molars	Higher risk, when anatomy and cooperation allow
Teens	Premolars and molars not yet sealed	Diet changes, braces, busy routines
Adults	Deep grooves free of decay, higher risk	Recent groove cavities, dry mouth, limited fluoride
Seniors	Rarely, on selected unrestored teeth	Most risk is on roots, where sealants do not apply

Children and teens

The CDC notes that sealants work best when applied soon after permanent molars come in: first molars around age six and second molars around age twelve. Sealing early protects the tooth during the years when groove decay is most likely.

Adults

Adults are not excluded. An adult with deep grooves on teeth that have no fillings, a recent history of groove cavities or reduced saliva may benefit on selected teeth. Teeth that already have large fillings on the biting surface are usually not candidates, because the grooves are no longer there to seal.

Early groove changes

The ADA notes that sealants can help arrest non-cavitated lesions, early changes in the enamel that have not become a hole. Your dentist may seal a groove like this and monitor it. A tooth with an actual cavity needs a filling first.

Children who find dental visits hard

Children with a strong gag reflex, anxiety or sensory sensitivities may need shorter visits or one or two teeth at a time. Ask the team what would help; sealants are often still possible with adjustments.

How dental sealants are placed

Sealant placement is usually quick and comfortable. For each tooth:

1. Clean. The chewing surface is cleaned to remove plaque from the grooves.
2. Isolate and dry. The tooth is kept dry with cotton rolls or a small isolation device. Keeping saliva away is the most important step for a lasting bond.
3. Condition. A mild etching gel is applied to the enamel for a short time, then rinsed and dried, so the sealant can grip the surface.
4. Apply. The sealant is painted into the pits and fissures.
5. Set. A curing light hardens resin sealants in seconds.
6. Check. The dentist or hygienist checks coverage and the bite, and adjusts any high spot.

Healthy enamel is not drilled, and freezing is usually not needed. Your child can normally eat and drink as soon as the appointment ends, unless other treatment was done at the same visit.

How long do sealants last?

Sealants can protect a tooth for years, but that is a general range, not a warranty. The CDC figures show protection continuing for up to four years for many children, and some sealants last well beyond that. Chewing forces, grinding, sticky foods and moisture during placement can shorten their life.

Sealants are checked at every recall visit. The hygienist and dentist look for:

• missing or partially lost areas;
• chips or wear on the biting surface;
• stain or gaps at the edges;
• new decay next to or under the sealant.

If a sealant is worn or partly missing and the tooth is still healthy, it can often be repaired or replaced in a short visit. Do not assume a sealant placed in childhood is still intact in adulthood without a check.

Aftercare at home is simple. Brush over sealed teeth as usual with fluoride toothpaste. Avoid chewing ice, hard candy and pen caps, which can crack sealants. If a sealant feels rough or a piece comes off, call for a check rather than waiting until the next recall.

Are dental sealants safe?

Dental sealants have a long track record. Most concerns relate to bisphenol A (BPA), a chemical linked to some plastics.

The Canadian Dental Association states that the amount of BPA from dental sealants has always been extremely small and limited to a few products, that any exposure occurs within the first hours or days after placement and then drops to virtually nothing, and that dental materials are well within safety margins according to Health Canada's assessment. The ADA similarly describes the potential exposure as minuscule.

Tell your dentist about any allergies or reactions to dental materials. If you want to reduce even the small initial exposure, you can ask whether rinsing after placement is suitable. Home "tooth coating" products are not the same as professionally placed sealants.

Sealants vs. fluoride vs. fillings

Sealants, fluoride and fillings are often mentioned together, but they do different jobs. A sealant is a barrier over healthy grooves. Fluoride strengthens enamel on every surface it touches. A filling repairs a tooth after decay has already created a cavity.

	Dental sealant	Fluoride treatment	Filling
Purpose	Prevent groove decay	Strengthen enamel, reverse early decay	Repair a cavity
Surfaces	Chewing-surface pits and fissures	All exposed enamel and roots	The damaged area only
Tooth condition	Sound or very early changes	Any, especially higher-risk teeth	Decay or damage present
Drilling	No	No	Usually, to remove decay
Freezing	Usually not needed	Not needed	Often used
Follow-up	Check and repair at recalls	Repeat according to risk	Monitor edges for new decay

For many children, the strongest plan combines them: sealants on newly erupted molars, fluoride toothpaste every day, professional fluoride when risk is higher and a filling only if decay gets past those defences. For adults, the balance usually shifts toward fluoride and home care, with sealants on a few selected teeth.

A common question from parents is whether a sealed tooth can skip brushing. It cannot. The sealant protects the groove, but the sides of the tooth and the gumline still collect plaque every day. Brushing twice daily with fluoride toothpaste and cleaning between teeth remain the base of every prevention plan.

What sealants do not do

Sealants are targeted protection, and their limits are worth knowing:

• They do not protect between teeth. Cavities that start where teeth touch need flossing and fluoride.
• They do not replace fluoride. Sealants cover grooves; fluoride treatment and fluoride toothpaste strengthen all enamel surfaces.
• They do not treat an existing cavity. Decay that has formed a hole needs restorative care.
• They do not protect root surfaces. Adults with gum recession need other strategies.
• They do not replace checkups. Sealed teeth still need monitoring.
• They do not protect against grinding. Heavy grinding wears sealants faster; a night guard is a separate discussion.

Cost factors. Fees depend on how many teeth are sealed and whether any teeth need early-lesion care first. Many private plans cover sealants for children's molars with age or tooth limits, so check your plan before booking.

Sealants for Truro and Colchester County families

Landmark Dental Care places sealants for children and selected adult teeth at 125 Queen St in downtown Truro, and sees families from Bible Hill, Colchester County and across Central Nova Scotia. The office is open Monday to Friday, 8:30am to 5:00pm.

A good time to ask about sealants is at the checkup after your child's six-year molars or twelve-year molars have fully come in. The dentist can tell you which teeth are ready and whether any grooves already show early changes. For a sense of how often your child should be seen, see how often you should go to the dentist.

Nova Scotia's Children's Oral Health Program, billed through MSI for children 14 and younger with a valid health card, lists an annual exam, X-rays, a fluoride treatment, scaling, fillings and necessary extractions on its current program page. Sealants are not listed there, so please call the office or MSI to confirm current sealant coverage for your child. As of 2026, the federal Canadian Dental Care Plan lists sealants among its preventive services, according to canada.ca. Eligibility requires no access to dental insurance and an adjusted family net income under $90,000. Please call to confirm current CDCP participation and billing, and see our CDCP page.

FAQ

Are dental sealants worth it?

For children and teens with newly erupted molars, the evidence says yes: sealants substantially lower the chance of groove cavities while they stay in place. For adults, the value depends on groove depth and cavity risk, which your dentist can assess.

Are sealants only for kids?

No. Children and teens are the most common candidates, but adults with deep, unfilled grooves and higher cavity risk may also benefit on selected teeth.

Does getting a sealant hurt?

Sealants usually need no freezing or drilling, so most children find the visit easy. The hardest part is often keeping the tooth dry for a few minutes.

What age should my child get sealants?

Sealants are often placed soon after the first permanent molars erupt around age six and the second molars around age twelve. Timing depends on when each tooth has fully come in.

Can a cavity form under a sealant?

It is possible if the sealant loses its seal or if early decay was already present. That is why sealants are checked and repaired at recall visits.

Next step

To find out which of your child's teeth, or your own, may benefit, see how sealants fit into preventive dentistry at Landmark Dental Care. Call 902-893-2919 or contact us to book a checkup at 125 Queen St, Truro.

References

• Centers for Disease Control and Prevention: About Dental Sealants
• American Dental Association: Dental Sealants
• MouthHealthy (ADA): Sealants
• Canadian Dental Association: Bisphenol A FAQs
• Government of Nova Scotia: Children's Oral Health Program
• Government of Canada: Canadian Dental Care Plan coverage

This article provides general educational information and is not a diagnosis or a substitute for care from a dentist or other qualified health professional.