Acne scar treatment: which technique for which scar
Rolling, boxcar and icepick scars need three different things. Most faces have all three.
Written and clinically reviewed by Dr. G. Revanth, MBBS DDVL DNB · August 2026 · 3 min read
Rolling scars need subcision to release the tethering bands beneath them, boxcar scars need punch techniques or resurfacing to soften their edges, and icepick scars need TCA CROSS applied inside the scar. Most faces have all three, so a plan is a sequence of three to six sessions six to eight weeks apart, not a single procedure.
Identify the scar before choosing the treatment
| Type | What it looks like | Primary technique |
|---|---|---|
| Rolling | Broad, shallow, undulating. Worse in raking light. | Subcision |
| Boxcar | Sharp vertical edges, flat base, like a small crater. | Punch elevation or excision, then resurfacing |
| Icepick | Narrow, deep, as though pierced with a pin. | TCA CROSS |
| Atrophic macular | Flat, discoloured rather than indented. | Pigment and vascular management |
What each technique actually does
Subcision
A blade is passed under the scar to divide the fibrous bands tethering the skin to deeper tissue. The release itself lifts the depression, and the controlled bleeding beneath triggers new collagen in the space that was created. Expect bruising, and plan your week around it.
TCA CROSS
A high concentration of trichloroacetic acid is applied precisely inside an icepick scar with a fine applicator, causing controlled injury at the base that fills as it heals. The surrounding skin is untouched. Crusts form and lift over five to ten days.
Punch elevation and excision
A boxcar scar with a flat base can be cut around and lifted flush with the surface, or removed entirely and closed. This converts a crater into a fine line, which is a better problem.
Resurfacing
Removes a controlled depth of epidermis so the surface heals more evenly. It refines what the other techniques have restructured; on its own it polishes a crater rather than filling it.
The honest ceiling
The realistic target is a meaningful reduction in shadow and texture, not smooth skin. That is quantified against your baseline photographs before treatment starts, in the same light, rather than promised as a percentage. Anyone offering to erase acne scarring is describing something that does not happen.
The rules that decide the outcome
- ✓SPF 50 every day of the course, reapplied. This is the single highest-impact thing you do.
- ✓Let every crust fall on its own. Picking is where a good result becomes a pigmented one.
- ✓Keep the acne itself controlled. New lesions make new scars.
- ✓Attend on the interval given. Six to eight weeks is the collagen remodelling window, not a diary convenience.
- ✕No retinoid or acids until specifically cleared, usually week three to four
- ✕No facials, threading or waxing for four weeks
- ✕No anti-inflammatory painkillers for seventy-two hours after subcision
Full protocol in the aftercare guide.