Do CO2 lasers and heat devices destroy skin cells?

Hello, My name is Ranen and I am an aesthetic nurse at Shah facial plastics. That’s an excellent and very insightful question — and you’re absolutely right that at first glance, it sounds contradictory:
why would we deliberately apply heat that damages tissue and call it rejuvenating? You’re right: heat does cause cellular injury — but it’s controlled

When you read that 46–60°C temperatures can cause irreversible cellular damage, that’s true in general. But in aesthetic medicine, the key difference is how deep, how long, and how precisely that heat is delivered. Controlled thermal injury is what devices like radiofrequency (RF), ultrasound (Ultherapy), laser resurfacing, and plasma are designed to create. The goal is to cause microscopic, selective injury to targeted tissue layers — just enough to trigger your body’s natural wound healing and remodeling response, not widespread tissue death. Think of it like a micro “reset” for aging or lax skin. When the skin is mildly injured in a controlled way: Fibroblasts (the collagen-producing cells in your dermis) are activated. They produce new collagen, elastin, and extracellular matrix — the proteins that give youthful skin its firmness and elasticity. Old, damaged collagen is broken down and replaced. So while some cells are destroyed, the repair process produces new, better-organized collagen fibers over weeks to months — that’s the rejuvenation effect.