Understanding the Mechanisms of Acne Scar Treatment: Collagen Stimulation Approaches

What are the primary principles behind the treatment of acne scars, specifically in stimulating collagen production to fill in the indentations?

Based on step 2, which generate wound to stimulate bone collagen reorganization and new growth, how long does it last for step 2 and step 3?

1) Utilizing lasers to create controlled wounds.
2) Employing microneedling to induce micro-injuries.
3) Applying manual pressure to create trauma.

Which of these methods is most effective in promoting collagen synthesis for the improvement of acne scars at initial stage?

Any suggestions?
Thanks in advance for any suggestions