What should be done if additional sealant needs to be applied after contamination?

In situations where additional sealant needs to be applied after contamination, it's essential to ensure that the bonding surface is adequately prepared to achieve a strong adhesion. The appropriate response in this case is to re-etch the surface. Re-etching helps to restore the enamel's ability to bond with the sealant by creating a fresh surface that is clean and receptive. This step is critical to ensure that the sealant adheres effectively, preventing future contamination and ensuring a long-lasting seal.

Drying the tooth thoroughly is also an important step in the sealant application process, as moisture can affect the adhesive properties of the sealant; however, it alone does not address contamination adequately. Similarly, re-polishing the surface would not eliminate contamination and would not provide the necessary bonding surface for the sealant. Applying sealant directly without re-etching runs the risk of contamination compromising the sealant's effectiveness, leading to potential failure of the seal. Therefore, re-etching the contaminated surface ensures that the sealant will bond properly and function as intended.