What is the primary biological effect of lasers when performing soft tissue procedures?

The primary biological effect of lasers in soft tissue procedures is photothermal. This effect results from the absorption of laser energy by tissue, leading to a localized increase in temperature. When soft tissues are exposed to laser light, the energy is converted into heat, which can cause a range of biological changes depending on the duration and intensity of the exposure.

Photothermal effects can lead to coagulation of blood vessels, which helps in minimal bleeding during procedures, and can also induce tissue contraction and shrinkage without the need for traditional surgical tools. This technique allows for precise cutting and shaping of soft tissues, reducing damage to surrounding areas and enhancing healing.

Other options, while they also describe potential effects of lasers, are not the primary effect in the context of soft tissue procedures. Photoablation refers to the removal of tissue through vaporization, which is generally more applicable to hard tissues or superficial layers of skin rather than deeper soft tissue applications. Photochemical effects involve chemical changes initiated by light, which are not the predominant mechanism in laser therapy for soft tissues. Mechanical effects, though present, are typically not associated with the primary function of lasers, as the laser's ability to cut and coagulate tissues relies more on thermal properties than on direct mechanical actions.