What material is typically applied to enhance the retention of sealants?

The correct choice, etchant, is used in the dental sealing process to enhance the retention of sealants. Etchant typically contains phosphoric acid, which is applied to the tooth surface prior to the placement of the sealant. The etching process creates a roughened surface by removing some of the enamel and increasing the surface area for the sealant to adhere to effectively. This micromechanical retention is crucial because it significantly improves the bond strength between the tooth surface and the sealant material, helping to prevent dental caries under the sealant.

While composite resin and bonding agents play important roles in other dental restorative procedures, they are not specifically applied to enhance the retention of sealants. A temporary filling is used to protect a tooth before a more permanent restoration can be placed, but it does not have a function in sealant retention.