What is the primary cause of sealant failure?

Moisture contamination is the primary cause of sealant failure because it prevents the sealant material from adhering properly to the tooth surface. For sealants to bond effectively, the application area must be completely dry and free of contaminants like saliva or blood. If moisture is present during the sealing process, it can interfere with the polymerization of the sealant and hinder its ability to form a secure bond. This not only compromises the effectiveness of the sealant in preventing decay but also leads to premature failure, as the sealant can easily dislodge.

In contrast, while inadequate curing, improper bonding, and insufficient material can also contribute to sealant failure, they are generally not as critical as moisture contamination. Proper curing is dependent on several factors, including the type of sealant used and the manufacturer's instructions. Similarly, bonding can be affected by various procedural aspects, but the presence of moisture right at the application stage poses the most immediate risk to ensuring a successful seal. Hence, understanding the importance of maintaining a dry field during sealant application is crucial for a dental assistant to prevent failure.