What are dental sealants?
Dental sealants are thin, plastic coatings that seal over the narrow grooves found on the chewing surfaces of back teeth (molars and premolars).
When placed perfectly on these deep pits, sealants can prevent a significant amount of tooth decay (cavities) by protecting sensitive tooth surfaces from acid that causes cavities.
Sealants are not generally placed on baby teeth but on the tooth enamel of permanent teeth (“adult” teeth).
Dental sealants function much like sealing cracks in a driveway or on the sidewalk. The grooves in the chewing surfaces of back teeth are sealed so that food particles and bacteria will not settle within the fissures, causing cavities.
Dental sealants can be placed by your dentist, dental hygienist, or other dental professional. Some states dental boards have laws governing by whom, how, and in what circumstances dental sealants can be placed.
While I will recommend sealants at my office, I do so with very strict criteria, application techniques, and only the cleanest materials. So, are dental sealants worth it for your children’s dental health?
How are sealants applied to teeth?
Sealant placement is a relatively easy process.
- First, the teeth are cleaned of plaque or food particles and then thoroughly examined for tooth decay.
- Each tooth is dried and surrounded by absorbent material so it remains dry throughout the procedure.
- The tooth is cleaned with a mild etchant (acid etch solution) to roughen the tooth surface and encourage bonding of the sealant material.
- The etchant is rinsed and the teeth are dried again.
- Depending on your material of choice, a thin layer of bonding agent may be used prior to the placement of the very viscous sealant material.
- The sealant is painted directly onto the chewing surface of each tooth.
- Finally, a curing light may be used to harden the dental sealant.
The teeth must be nicely isolated so no contaminants, such as saliva, affect the bond. Ozone gas can be applied to ensure bacteria on or around the tooth is reduced or eliminated prior to sealing.
If a small cavity is detected, air abrasion or a dental laser or drill can be used to clean out the infection prior to any material placement.
Can a sealant be placed over existing tooth decay?
Technically, clear sealants can be used over small cavities to prevent major spread of the decay.
However, it’s best to treat any existing decay (or take steps to reverse it, depending on the extent of the decay) before placing a dental sealant.
How long do dental sealants last?
Depending on the techniques used, sealants can last from 3-10 years or more.
Sealants may not last as long for patients who:
- Clench/grind their teeth
- Have acid reflux
- Eat a highly acidic diet
How do I care for my sealants?
Dental sealants are easy to care for and can be brushed and flossed as normal. Use a toothbrush with soft bristles and a toothpaste using a remineralizing agent like hydroxyapatite.
Do dental sealants work?
Do dental sealants prevent cavities? Yes, sealants do work to prevent cavities (tooth decay) if placed perfectly and at the right time.
Most research shows that sealants do reduce cavities, but more long term follow-ups are needed.
In a 2017 Cochrane review, researchers stated that “resin‐based sealants applied to occlusal surfaces of permanent molars reduced caries when compared to no sealant.” However, “trials with long follow‐up times are needed to research the effectiveness of sealing procedures related to different caries prevalence levels.”
The CDC (Centers for Disease Control and Prevention) found in a 2016 study that “Children without sealants had almost three times more cavities in permanent first molars compared with children with sealants.”
The same study stated that dental sealants can prevent 80% of cavities in permanent molars (where 9/10 cavities develop).
This study did not control for dietary patterns, dental hygiene habits, or level of dental care during the same period of time. It only controlled for sex, race/ethnicity, family income, and highest level of education by the head of the household.
Why does this matter? It’s possible that confounding variables — such as diet, dental visits, or dental hygiene habits — may have artificially inflated these numbers.
For example, children who received dental sealants may also have visited the dentist, brushed, and flossed more often. They may be the same children who do not eat sugary or highly acidic foods, which will impact cavity formation.
These statistics should be examined with a hefty grain of salt.
Who should get dental sealants?
Children who benefit most from dental sealants include those:
- With very deep grooves in their molars
- At a high risk for cavities
- Who eat a diet high in processed foods, refined flours and sugars, and sugary drinks
- With special needs that make dental hygiene and/or a healthy diet more challenging
Ideally, sealants should be placed immediately after the eruption of the first molars (around age 6) and second molars (around age 12). Sooner is better to ensure the grooves have not been affected with bacteria or early cavities.
Sealants in Adults
In general, dental sealants are not used on adults, though some sources like the CDC and ADA claim they can help prevent decay. (This has not been tested in clinical trials.)
Dental sealants for adults may not be a good idea because the tooth has been exposed to the oral microbiome for a much longer time. Complex systems of bacteria are more likely to be trapped under the sealant in a deep groove.
To place a dental sealant in an adult tooth, it is important that the grooves be drilled out, treated with ozone, and immediately sealed. This best reduces the risk of growing decay under the sealant material.
Can dental sealants be removed?
Dental sealants can usually be removed in a quick and easy procedure involving either a laser or a dental drill to carefully remove the material used.
This leaves the healthy tooth structure intact, after which it can be resealed if desired.
Removing dental sealants is done to:
- Reseal the tooth with a ceramic sealant (which is considered “cleaner” than traditional sealant)
- Correct chips or cracks in existing dental sealants
- Eliminate poorly placed sealants
- Expose buried decay that can then be restored
Once a sealant is placed, it’s generally not removed unless a dentist spots a problem or the patient (or parent) requests it for other reasons, such as to change the materials being used.