What does fissure sealing involve?
Fissure sealing involves covering the grooves and pits on the chewing surface of the molars with a thin layer of liquid material, the sealant, which hardens and forms a tight barrier. The grooves are so narrow that a toothbrush cannot reach the bottom of them, and the plaque trapped there can easily start decay.
The most common sealants are resin-based, hardened by light or chemically; glass ionomer materials form a separate group. Sealing is done on a healthy tooth or on a tooth with a very early lesion without a cavity, because its purpose is prevention, not treating a hole.
Fissure sealing should not be confused with fluoride varnish, that is, applying a varnish containing fluoride. These are two different procedures, and the differences between them are set out in a table later in this article.
Does fissure sealing work? What the research says
Fissure sealing works: a 2017 Cochrane review (38 studies, 7 924 children) found that in children aged 5 to 10, sealing the first permanent molars with a resin-based sealant clearly reduces the risk of decay on the chewing surface after 24 months. In practical terms this means 11 to 51% fewer decayed surfaces, depending on how high the initial risk was.
The review gives an example: if without sealing decay appears on 40% of surfaces, after sealing it affects about 6%. The benefit is also seen after 48 to 54 months, although these data are less certain. For glass ionomer sealants the results were inconclusive, and which material protects better remains unresolved.
An important caveat: 5 of the 7 key studies date from the 1970s, before fluoride toothpaste was in widespread use, so the figures are best treated as approximate. The 2016 guidelines of the American ADA and AAPD nevertheless consider sealing effective in preventing decay in the grooves of milk and permanent molars in children and adolescents.
When should a child’s teeth be sealed?
A child’s teeth are sealed soon after the chewing surface of the permanent molars has come through: the first molars, the ‘sixes’, usually at around the age of 6, and the second molars, the ‘sevens’, at around the age of 12. The American Dental Association (ADA) recommends sealing molars as soon as they come through and stresses that the earlier, the better.
Children with deep grooves and a higher risk of decay benefit most. Milk molars can also be sealed, and the ADA states that adults can benefit from sealants too; the dentist decides whether sealing is indicated after looking at the teeth.
It makes sense to combine sealing with a check-up, at which the dentist assesses anyway whether the new teeth have come through and what their grooves look like. A tooth that has only partly come through is usually sealed later, once its chewing surface is fully exposed.
Fissure sealing on the NFZ: up to what age and how many times?
Fissure sealing on the NFZ is available once per tooth: the first permanent molars up to the age of 8, and the second permanent molars up to the age of 14. Older information about a limit of 7 years still circulates online, but the current regulations specify 8 years (law as at 12 October 2026).
Since 2025 the NFZ has also funded preventive protection of the grooves with other materials for children, referred to as PRR type 1 (preventive resin restoration). The regulations do not make clear whether topping up a sealant after it chips is funded, so it is worth asking about this at a practice with an NFZ contract.
| Procedure on the NFZ | Which teeth it covers | Limit |
|---|---|---|
| Sealing the sixes | First permanent molars | Once, up to the age of 8 |
| Sealing the sevens | Second permanent molars | Once, up to the age of 14 |
| PRR type 1 | Grooves of the permanent molars | A service for children and young people since 2025 |
| Fluoride varnish | The child’s teeth | No more than once every 3 months, up to 18 |
How is fissure sealing done, and does it hurt?
Sealing is quick and, according to the ADA, painless: the dentist cleans and dries the tooth, applies a gel that prepares the enamel for a few seconds, rinses it off, dries the tooth again and works the sealant into the grooves. Finally the sealant is hardened with a curing light or, with some materials, sets on its own.
After sealing the child can eat and drink straight away: the US Centers for Disease Control and Prevention (CDC) states that there are no restrictions. The stages of the procedure are as follows:
- Cleaning the chewing surface of the tooth and drying it thoroughly.
- Applying an acidic gel for a few seconds, which slightly roughens the enamel so that the sealant bonds well.
- Rinsing off the gel and drying the tooth again.
- Working the liquid sealant into the grooves and pits.
- Hardening the sealant with the blue light of a curing lamp.
Fissure sealing and fluoride varnish: how do they differ?
Fissure sealing and fluoride varnish are two different procedures: sealing closes the grooves of the molars with a durable layer of material, while fluoride varnish coats the teeth with a varnish containing fluoride, which strengthens the enamel and is applied at intervals. The two procedures complement each other rather than being alternatives.
Fluoride varnish protects all the surfaces of the teeth, including those between the teeth and along the gum, which a sealant does not cover. Sealing, in turn, protects the deep grooves of the chewing surface, where a toothbrush has the hardest job and fluoride alone is not always enough.
| Feature | Fissure sealing | Fluoride varnish |
|---|---|---|
| What it involves | Sealing the grooves with a liquid sealant that hardens | Coating the teeth with a varnish containing fluoride |
| Which teeth it covers | Mainly molars, the chewing surface | Milk and permanent teeth, all surfaces |
| How it works | A mechanical barrier against plaque | Fluoride strengthens the enamel |
| How often | Once, with checks and topping up when needed | At intervals, on the NFZ no more than once a quarter |
| What the research says | Cochrane 2017: 11 to 51% fewer decayed surfaces | Cochrane 2013: about 43% less in permanent teeth and 37% in milk teeth |
| NFZ | Sixes up to 8, sevens up to 14, once per tooth | Up to 18, no more than once a quarter |
How long does a sealant last, and what if it chips?
A sealant usually lasts several years, but it can partly chip away, which is why it is checked at check-ups. In a review of studies (Kühnisch et al., 2012), after 5 years 83.8% of light-cured resin sealants, 64.7% of chemically cured ones and less than 19.3% of glass ionomer and compomer sealants were still fully intact.
The ADA states that the dentist checks the condition of the sealant at check-ups and reapplies it if needed. Partial loss of the sealant does not mean decay straight away, but the groove is no longer fully protected, so it is worth topping it up.
Is fissure sealing harmful?
Fissure sealing is not considered harmful: in the Cochrane review only 4 studies reported on adverse effects, and none of them recorded any. A question that often comes up concerns bisphenol A (BPA); the ADA’s answer is that sealants contain a trace amount of it, not enough to cause harm.
Sealing protects only the chewing surface of the molars. It does not replace brushing with fluoride toothpaste, cutting down on sugary drinks and snacks, or check-ups with the dentist, because decay can also start between the teeth and along the gum.
How much fissure sealing costs at DentalBlue
DentalBlue in Białystok provides preventive dentistry: professional cleaning, fissure sealing and fluoride treatment. In the clinic’s price list, sealing 1 tooth costs 220 zł, sealing with widening of the fissure 260 zł, fluoride treatment 100 zł, and cleaning a child’s teeth with fluoride treatment 250 zł. Whether ordinary sealing is enough or sealing with widening is needed is decided by the dentist after looking at the grooves. The final scope and cost are set at the visit, and prices may change. An appointment can be booked by phone.
Frequently asked questions
How long after fissure sealing can my child eat?
Straight away. The CDC states that after sealing a child can eat and drink as usual, with no restrictions, because the sealant hardens while still in the surgery, under the lamp or on its own.
Are milk teeth sealed?
Yes, when the dentist sees a need for it. The 2016 ADA and AAPD guidelines consider sealing effective in preventing decay in the grooves of both milk and permanent molars. The NFZ lists sealing of permanent molars, so milk teeth are worth discussing at the visit.
Can adults have their teeth sealed?
They can. The ADA states that both children and adults benefit from sealants, although the earlier, the better. The NFZ funds sealing for children of specific ages, so an adult pays for it themselves, and the dentist decides whether it is indicated.
Can a tooth with early decay be sealed?
In some cases, yes. The ADA states that a sealant can be applied over an area of very early decay to stop it progressing, and the ADA and AAPD guidelines indicate that sealing can slow down lesions without a cavity. Once the tooth has a hole, it needs treatment.
How often does fissure sealing need to be repeated?
Sealing is not repeated on a fixed schedule. The dentist checks the sealant at check-ups and tops it up when it chips; the ADA states that a sealant often lasts several years before it needs reapplying.
Sources
- Cochrane: Ahovuo-Saloranta A et al., fissure sealants for preventing decay in permanent teeth (2017)
- Pediatric Dentistry: ADA and AAPD guideline on fissure sealants (2016)
- Dental Materials: Kühnisch J et al., retention of pit and fissure sealants, meta-analysis (2012)
- ADA MouthHealthy: Sealants (undated)
- CDC: About Dental Sealants (2024)
- NFZ: Poradnik pacjenta, stomatolog dla dzieci, co na NFZ (2024, updated 2025)
- Dz.U. 2025 poz. 615: Rozporządzenie MZ w sprawie świadczeń z zakresu leczenia stomatologicznego, consolidated text (2025)
- Cochrane: Marinho VCC et al., fluoride varnishes for preventing decay in children and adolescents (2013)
An informational article. It does not replace a consultation, and treatment decisions are made during a visit.
