Non-thermal effects promote healing through which mechanism?

• A. Dehydration of tissues
• B. Tissue necrosis
• C. Biophysical changes
• D. Increased nerve conduction velocity

Answer: (C)

Non-thermal effects promote healing through biophysical changes at the cellular and tissue level. These modalities deliver mechanical or photobiological signals without raising tissue temperature, altering cell membranes, signaling pathways, and microcirculation to boost repair processes. For example, pulsed ultrasound can create acoustic streaming and microstreaming that stimulate fibroblasts, enhance collagen synthesis, and promote angiogenesis, all contributing to healing without heat. Dehydration of tissues and tissue necrosis are not how these non-thermal modalities work, since they describe damage or drying rather than the healing signals produced. Increased nerve conduction velocity is more related to temperature effects than to the non-thermal healing mechanisms described here.