What is true in regard to marginal leakage in amalgam?

In the context of marginal leakage in amalgam restorations, the statement regarding the relationship between the gap size and the risk of secondary caries is accurate. Marginal leakage happens when there is a gap between the tooth structure and the dental material used, such as amalgam. If there is a wider gap, it creates an environment that allows bacteria and food particles to enter more easily, leading to a higher risk of secondary caries.

These secondary caries can develop over time in areas where leakage occurs, as the microbial environment can thrive, causing demineralization and decay of the tooth structure adjacent to the restoration. This understanding is essential for dental professionals as they seek to optimize restoration longevity and patient outcomes.

While sealing the margins with a fissure sealant may help in some cases, relying solely on this method doesn't address the fundamental problem of the gap itself, and it is not universally applicable to all situations involving amalgam restorations. Therefore, while some preventive measures exist, the presence of a wider gap fundamentally correlates with increased risk for secondary caries, making the first statement notably valid in this context.