Is the fractional radiofrequency, CO2 laser or erbium laser more effective for deep acne scars?

With regards to your question:

1. Fractional CO2 lasers generally penetrates deeper than Erbium lasers
2. Fractional CO2 lasers also generally penetrates deeper than Fractional RF devices EXCEPT Microneedle RF machines that can reach a depth of 3.5mm (only in some machines) which in this case will have a greater penetration depth as compared to Fractional CO2 machines.

Fractional CO2 lasers also generate more heat than Erbium lasers and as such have better collagen synthesis etc but this also confers a higher risk of heat-related side effects namely Post-Inflammation Hyperpigmentation (PIH) , redness and longer downtime.

As the other doctors have mentioned, this is where Fractional RF machines have a safer side effect profile with a lower risk of PIH.

That being said, one would also have to consider the type of acne scars you have as different scars are treated differently and not all scars respond well to machine-led treatments.

In conclusion, all these devices have their pros and cons, and can deliver good results when executed to its full potential.

Hope that helps.

All the best!