Which mechanism contributes to the effectiveness of Er:YAG laser in dentistry?

The effectiveness of the Er:YAG laser in dentistry is primarily due to its high absorption in water. This characteristic is crucial because dental tissues, including both hard and soft tissues, have a significant water content. When the Er:YAG laser is applied, its energy is efficiently absorbed by the water within these tissues. This absorption leads to effective ablative action, allowing for precise removal of dental hard tissue, such as enamel and dentin, while minimizing thermal damage to surrounding areas.

High absorption in water also supports a mechanism called "photothermal ablation," where the water rapidly vaporizes, creating micro-explosive effects that aid in cutting or ablating tissue with minimal collateral damage. This specificity is particularly important in dental procedures, where the precision of the laser contributes to better outcomes, less discomfort for the patient, and improved healing times.

In contrast, mechanisms like low absorption in water would reduce the laser's effectiveness by not leveraging the tissue's water content for ablation. Non-selective energy delivery could lead to excessive damage to healthy tissues surrounding the target area, and depth penetration is less critical in this context, as the primary advantage comes from the interaction with the water in the targeted tissues.