Dental Sealants for Children and Teenagers

What exactly are dental sealants?

A dental sealant — often called a fissure sealant in the UK — is a thin, tooth-coloured coating painted into the grooves on the chewing surfaces of back teeth. It is made from a resin material similar to that used for white fillings, and once it has set hard it forms a smooth, protective barrier over the deepest parts of the tooth.

The important thing to understand is that a sealant is not a filling. No drilling is involved, and no healthy tooth is removed. The tooth is simply cleaned, dried and then coated. Think of it as a raincoat for the parts of a tooth that a toothbrush cannot quite reach.

Why back teeth need the extra help

Molars and premolars are built for grinding, which means their surfaces are full of hills, valleys and narrow grooves called fissures. Some of those fissures are narrower than a single toothbrush bristle, so even a child who brushes thoroughly twice a day may leave food debris and bacteria sitting at the bottom of them.

Those trapped bits of food feed on sugar and produce acid, and because the grooves are so tight, saliva — which normally helps neutralise acid and wash teeth clean — cannot get in to do its job. The result is that most decay in children's permanent teeth starts in exactly these grooves. Sealants close that gap. The smooth surface left behind is easy to brush and gives bacteria nowhere to hide.

Who benefits most from sealants?

Sealants are most commonly offered to children and teenagers at the point when their back teeth are coming through. Your dentist will usually consider them for:

• Children whose first permanent molars have erupted, typically around the age of six or seven
• Teenagers getting their second permanent molars, usually between 11 and 13
• Children with deep, narrow or sticky grooves that are hard to keep clean
• Anyone with a history of decay, or with a brother or sister who has had a lot of decay
• Children with enamel defects, additional needs, or conditions that make brushing difficult
• Occasionally, baby molars in a child at high risk of decay, if the tooth is expected to stay in place for several more years

The ideal moment is as soon as a tooth has come through enough to be kept dry, but before decay has had a chance to begin. Once a groove is already decaying, a filling is usually the better option.

What happens during the appointment

The procedure is quick, painless and usually needs no numbing injection. A typical visit looks like this:

• The dentist or dental therapist cleans the tooth with a small brush and paste, then rinses and dries it
• A soft rubber dam or cotton wool rolls keep the tooth dry — moisture is the enemy of a good seal
• A mild acid gel is applied for a few seconds to create a slightly roughened surface, then washed away
• A bonding agent is painted on, followed by the sealant itself, which is flowed into the grooves
• A bright blue light sets the material hard in seconds
• The bite is checked and any high spots are smoothed away

Each tooth takes only a few minutes, so a full set of four molars can often be done in one short appointment. Your child can eat and drink normally straight afterwards — though it is wise to avoid very hard or sticky sweets for the rest of the day.

How long do sealants last?

A well-placed sealant usually lasts between five and ten years, and sometimes longer. They do wear down over time, and heavy grinding or chewing on ice and hard sweets can chip them. This is why your dentist will check them at every routine examination — a sealant that has partly worn away can often be topped up or replaced in minutes.

It is worth being clear about what sealants do not do. They protect the grooved chewing surfaces only. They do nothing for the sides of teeth where decay also commonly starts, so cleaning between the teeth still matters. Sealants also work best alongside the basics: brushing twice a day with a fluoride toothpaste, spitting rather than rinsing after brushing, keeping sugary snacks and drinks to mealtimes, and any fluoride varnish your dental team recommends.

Questions worth asking your dentist

• Are my child's molars erupted enough to be sealed?
• Which teeth would you recommend sealing, and why those ones?
• Is there any decay already present in the grooves?
• Is this available on the NHS for my child?
• When should we next review them?

NHS dental treatment is free for children under 18, and sealants are provided as part of NHS care where they are clinically appropriate. If your child is nervous, it helps to explain beforehand that there is no drill and no needle — most children find the whole thing far less dramatic than a scale and polish.