Larger structures have _______ thermal relaxation times (TRT).

Larger structures have longer thermal relaxation times (TRT) due to their greater mass and the larger volume of tissue that must be heated and subsequently cooled. Thermal relaxation time refers to the duration it takes for tissue to return to its baseline temperature after being exposed to a thermal source such as laser energy.

When a larger structure is heated, the increased volume means that there is more tissue to absorb and dissipate heat. This results in a slower rate of temperature change, as the heat needs to be evenly distributed throughout the larger area. Consequently, the cooling process also takes longer, contributing to an extended TRT. This understanding is crucial in laser treatments, where timing and heat management are essential for effectiveness and safety, ensuring that the surrounding tissue does not incur damage while targeting specific areas for treatment.