Our Amazing 5-point Guide to Dental Sealants

Dr. Kyle Hornby

Hi! I'm Kyle Hornby and I'm a Family Dentist in Kitchener-Waterloo. I'm big on making sure readers get the information they need to make the best dental decisions for themselves and for their family. This week, I thought I'd write a comprehensive guide on Dental Sealants.

Here's the breakdown of sections in the article in case you want to jump around:

So...should your child get dental sealants?

This is a really popular question that we get frequently from the wonderful parents who visit our clinic. It's a great question but there is, in fact, no perfect answer.

The answer depends on many factors such as the likely preventive benefit to the child (i.e. are they cavity-prone or not?).

There are also other factors including risks posed by dental sealants (that's right, there are some risks associated with sealants).

My goal with the 5-point guide below is to address some of the most important pieces of information about dental sealants so that you can evaluate if they're right for your kids.

Alright, so let's get right into this...

What do dental sealants do (or rather, what have you been told that dental sealants do)?

First of all, this is not a conspiracy theory article. Dentists have long advocated for the use of dental sealants because they are placed in the spirit of prevention. And, prevention is really, really important.

However, people might not be told about the potential negatives and risks associated with things they buy and treatments they undergo.

For this reason, many parents are often surprised to hear that I'm not 100% in favour of dental sealants. And, again, the reason for this is that they're not perfect and they pose some risks.

That means, it makes more sense to take on those risks where possible benefits are huge. Specifically, sealants make more sense in patients who are super-cavity-prone, but not so much in patients who aren't.

Sometimes, we can identify cavity risk based on a child's diet (i.e. high-sugar or high-starch) or based on their past dental history (i.e. repeated treatment for cavities).

So, what are sealants designed to do?

Dental sealants are made of a bondable material that sticks to and covers the deep grooves on teeth. The sealant prevents dental plaque and harmful bacteria from settling into the bottom of these grooves, an area that your toothbrush bristles can't reach.

dental sealant
Molar teeth can have really deep grooves that trap dental plaque and bacteria, leading to cavities.

So, the dental sealant is a shield designed to keep the grooves on your teeth clean and decay-free.

But, what if those grooves aren't clean when the sealant is placed?

And, can sealants sustain damage that actually leads to a higher risk of tooth decay?

Those are great questions.

Do sealants always work?

No. Sealants don't always work. Any Dentist who's seen a dark shadow spreading out from underneath a dental sealant knows that. Sometimes, sealants lock in bacteria that eventually lead to a cavity.

Sealants are also at a higher risk of breaking and chipping compared to dental fillings. This is because sealants are very thin and shallow (if they were thicker, they'd affect the way your teeth fit together making your bite feel strange).

When dental sealants chip, they create ledges where the remaining sealant meets your tooth groove. This makes a plaque-trapping groove even more plaque-retentive and the risk of tooth decay at that site goes way up.

So, in short, sealants don't always work. But there's nothing that has a 100% success rate. What we really need to do is consider incurring the risks that come with dental sealants only when the potential benefit to the child is massive.

That is, dental sealants make the most sense in kids that get, or are likely to get, a lot of cavities.

So, if we've carefully case-selected kids who'll benefit most from the preventive effect of dental sealants, when do we place them?

Is there a best time to place dental sealants?




The dental sealant keeps bacteria out of deep grooves on teeth so your child doesn't get cavities.

Ideally, then, you want that sealant in place before the tooth has had much exposure to harmful bacteria and dental plaque (those 2 things drive cavity formation). This means that you'd like to have your Dentist (and it should be your Dentist placing the sealant) putting the sealants in place as soon as the chewing surface is visible and through the gums.

Now, the entire chewing surface has to be visible and accessible for a successful sealant placement. So, timing is absolutely critical to sealant success.

If you place the sealant too late, then your Dentist may be sealing in harmful bacteria without knowing it.

So, getting the timing right on sealant placement can really increase their success.

But...is it difficult to get the timing right?

Unfortunately, the answer is yes.

One reason for this is that your Dentist typically sees your child (only) every 6 months. So, when they're seeing newly erupted teeth, they've usually had their grooves exposed to bacteria and dental plaque for a while. That is, they're not usually freshly erupted (freshly erupted means the grooves on the top of the tooth have only broken through the gums within the past few days).

The likelihood that your Dentist, whom your child might see twice a year, catching a freshly erupted tooth is very low.

Add to this the fact that the same adult tooth (i.e. an adult 1st molar) doesn't erupt at precisely the same time in all 4 corners of the mouth. So, now you have a massive undertaking to keep track of when all adult teeth are erupting.

From there, what is the likelihood that you can get in to your Dentist's office quickly to have a sealant placed?

You're probably sensing that there are many factors that add up to it being very difficult to properly time dental sealant placement.

Again, this is not to say that dental sealants are bad. I just want readers to be aware of the challenges that arise with properly timing sealant placement to maximize benefit and minimize risk.

Is there a way to increase success rate on dental sealants?

Yes, there are definitely some ways to improve the durability and retention of sealants. These techniques can also eliminate bacteria from tooth grooves prior to sealant placement.

When a sealant is placed, your Dentist can make the decision to clean out the grooves or fissures on your child's tooth - this is called a fissurotomy.

The groove is cleaned out right down to it's deepest parts using a small cleaning bur and dental handpiece. These are the parts of the groove that can't be reached with toothbrush bristles (because they're diameter is too big) and, consequently, dental plaque and harmful bacteria can accumulate there.

A fissurotomy can be done without the need for dental freezing and can increase the success rate of dental sealant placement in two ways.

We already mentioned that a fissurotomy removes potentially harmful bacteria that might otherwise be locked in underneath a sealant. In addition to that, it can increase the retention and durability of a sealant by allowing it to anchor itself deeper into grooves. This reduces the likelihood that fragments break off or become dislodged over time.

What's in a dental sealant and can it be toxic?

I always encourage patients to be aware of what goes into their bodies. Importantly, many people have been told that Silver Amalgam fillings are bad and that they can be potentially harmful. But, dental composites (tooth-coloured filling material) and sealant materials can contain Bisphenols (BPA) and bis-GMA.

The reason you should be aware of this is that these filling materials look harmless but the BPA and bis-GMA they may contain are endocrine disruptors.

What's an endocrine disruptor?

An endocrine disruptor is a material or substance that can interfere with your body's natural hormone production.

That's serious stuff.

It's also important to note that dental sealant materials are less wear-resistant compared to white fillings so they break down more quickly. As layers of your sealant wear down, you're exposed to some not-so-organic materials.

We all really need to be careful and aware when evaluating what's being used on our bodies.

A Summary on Dental Sealants

You deserve to know what you're getting into with dental and medical treatments. With more information, you can evaluate risks and benefits to increase the likelihood that you're making the right call for yourself and for your kids.

The placement of dental sealants is preventive in nature, and prevention can be a really great thing. But, preventive treatments need to be provided on a case-by-case basis such that potential benefits far outweigh risks. And, it's not always an easy calculation to perform.

For sealants, I think it's important to target high-risk children who are cavity-prone. Protecting their tooth grooves from dental plaque and oral bacteria can really help to reduce their elevated risk of cavity formation.

Now, I have one final thought about dental sealants...and please hang in there with me, because I'm going to give you some background info first...

Placing dental sealants, like many things in Dentistry, is super-technique-sensitive.

What does that mean?

Well, you have to keep a tooth completely dry for about 90-120 seconds to achieve a proper, sterile bond between your sealant material and tooth enamel. It can be challenging to achieve in a child because they produce a huge quantity of saliva very quickly. It's also challenging because you're targeting freshly erupted teeth with your sealant. These teeth are just barely through moist gum tissue, making it harder to keep them dry during placement.

For these reasons, it's important that your Dentist places the sealants for your child. Some other members of the dental office team can receive training to become accredited to place dental sealants. At some offices, sealants are placed by members of the dental team that are not the Dentist herself/himself.

I believe that the requirement to strictly control conditions (namely moisture) in a sometimes challenging oral environment demands the attention of your Dentist. So, where possible, try to make sure that the Dentist will be placing your child's Dental Sealants.

If you'd like to listen to a helpful podcast on Dental Sealants, Askthedentist.com's Mark Burhenne provides a great discussion on dental sealants, here.

Thanks for reading today's article! I hope you've found the read to be worth your time.

By Dr. Kyle Hornby, Kitchener, ON Dentist

Our Dentist Office is located in Downtown Kitchener, Ontario. We are a short drive away for families in Waterloo, Breslau & St. Jacobs. Our central location means we truly offer family dental care near you!

This article is not intended to be a substitute for professional advice, diagnosis, or treatment. Accordingly, always seek the advice of your Dentist or other healthcare providers regarding a dental condition or treatment.

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