What is the most common reason for sealants to fail?

The most common reason for sealants to fail is contamination. When a sealant is applied, the tooth surface must be clean and free from saliva, plaque, and other debris to ensure proper adhesion. Contamination can occur during the sealing process if the area is not adequately isolated from moisture, which can compromise the sealant's bond to the tooth surface. Even a small amount of saliva or moisture can lead to a weak bond, resulting in premature failure of the sealant as it may not fully adhere. This can allow bacteria to penetrate beneath the sealant, ultimately leading to caries development.

Inadequate retention can also contribute to sealant failure, but it often stems from issues related to contamination or improper technique during application. A poor light curing device might not properly cure the sealant, but this is less common when equipment is adequately maintained. Patient bruxing habits can put additional stress on sealants and lead to their failure over time, but this is not typically the primary reason for failure compared to contamination during the application process.