Dental sealants are a common preventive dental treatment. They consist of a thin, plastic coating painted onto the molars and premolars, acting as a shield against cavity-causing agents. The primary purpose of this treatment is to prevent the formation of cavities, which significantly improves a child’s oral health. This article provides factual information about dental sealants to address concerns regarding the safety of the materials used in this procedure.
How Dental Sealants Protect Teeth
The mechanism of protection is physical, targeting the unique anatomy of the back teeth. Molars and premolars have chewing surfaces containing depressions, grooves, and crevices called pits and fissures. These deep, narrow channels are susceptible to decay because toothbrush bristles cannot effectively reach them. Trapped food particles and bacteria produce acid that erodes the tooth enamel, leading to a cavity.
Dental sealants work by flowing into these pits and fissures and then hardening to create a smooth, protective layer. This coating physically blocks bacteria and food debris from entering the vulnerable grooves. The sealant transforms a complex, hard-to-clean surface into a smooth plane easily accessible for brushing. By creating this barrier, the sealant stops the decay process before it can begin.
Addressing the Chemical Safety Question
A primary concern involves the materials used in the sealant, specifically the potential presence of Bisphenol A (BPA). Most modern resin-based sealants use compounds like Bis-GMA or Bis-DMA, which are derivatives of BPA, not the chemical itself. Trace amounts of BPA can sometimes be released as a byproduct of components breaking down or as an unreacted impurity.
This chemical release is considered an acute event, occurring only immediately following application. Studies show that detectable BPA in the saliva dissipates rapidly, often within a few hours, and is undetectable after a day. The scientific consensus from organizations like the American Dental Association (ADA) and the Centers for Disease Control and Prevention (CDC) is that the level of exposure is extremely low.
The maximum BPA exposure from dental sealants is thousands of times lower than levels known to cause biological effects in animal studies. This exposure is also significantly less than what a child receives from common environmental sources, such as plastic food containers. The preventative benefit of avoiding tooth decay far outweighs the minimal, temporary exposure to these trace chemicals. Dentists can mitigate this initial release by polishing the sealant surface and having the child thoroughly rinse immediately after the procedure.
The Application Process and Child Comfort
The application of dental sealants is a straightforward, non-invasive procedure that does not involve drilling or local anesthesia, making it comfortable for children. The process begins with the dental professional thoroughly cleaning the chewing surface of the tooth to remove plaque and debris. Next, a mild acidic solution, known as an etchant, is applied to microscopically roughen the enamel. This prepares the tooth surface to create a strong bond with the sealant material.
After the etchant is rinsed off and the tooth is dried completely, the liquid sealant is carefully painted onto the pits and fissures. The material flows into the deepest grooves before a special curing light, typically blue light, is used to harden the sealant almost instantly. This entire process is quick, often taking only a few minutes per tooth.
Long-Term Integrity and Monitoring
Once cured, the dental sealant forms a durable, plastic coating that can withstand normal chewing forces. Most sealants last between five and ten years, though individual wear varies depending on oral habits and material type. During routine dental checkups, the dentist inspects the sealants for signs of wear, chipping, or partial loss.
If a sealant is lost or chipped, the protective barrier is compromised, but it poses no physical danger to the child. A worn sealant reduces the tooth’s protection, re-exposing the vulnerable pits and fissures to bacteria. The dentist can easily repair or replace a damaged sealant by cleaning the area and applying new material. This routine monitoring ensures the tooth remains protected throughout the child’s most cavity-prone years.