What a boxcar scar is
A boxcar scar is a round or oval dip with near-vertical walls and a flat base. It can be shallow or deep, and that depth decides the treatment. Boxcars often sit alongside rolling and ice pick scars, so the whole face is assessed rather than one scar alone.
Dr Sin Yong judges depth under side light, where the shadow inside the box shows how far down it goes. He then stretches the skin to check for a tether, because a tethered scar needs release first. Your Fitzpatrick skin type and pigment history are graded at the same visit.
Boxcar scars treatment Singapore: matching method to type
| Boxcar type | Method | Notes |
|---|---|---|
| Shallow | FSX Laser, or S3 at a light setting | FSX is non-ablative, with 1540 nm erbium glass and 1927 nm thulium. Settings are adjusted for Fitzpatrick V to VI |
| Deep | S3 Resurfacing Lift | Fractional CO2 at 10,600 nm on the DEKA Tetra Pro under local anaesthetic. Point shots go into each box, then fractional passes cover the surrounding skin |
| Tethered | Subcision first, with Radiesse where the floor is thin, then resurfacing | Release comes before resurfacing |
| Narrow, deep corner | TCA CROSS, then laser to even the surface | A microdroplet of 70 to 100% trichloroacetic acid |
| Shallow to moderate in Fitzpatrick IV to VI | Secret DUO RF microneedling or FSX Laser | Insulated needles, chosen where less surface injury is preferred |
| Small, isolated, very deep | Punch excision or elevation by referral | Resurfacing is planned around it |
Why depth changes the plan
A shallow boxcar may respond to a non-ablative laser, which brings a shorter recovery than the S3. A deep boxcar has steep walls that non-ablative energy and RF microneedling cannot ablate. These need fractional CO2, with density and depth set separately. Deep boxcars that have plateaued after earlier CO2 or RF microneedling may also be considered for the S3. Other tools cover narrow corners and tethered floors. The S3 is done under local anaesthetic. Point shots go into each box, then fractional passes treat the surrounding skin.
Why tethers and corners need their own step
A tethered boxcar is anchored from below, so resurfacing alone treats a scar that is still being held down. Subcision divides the band through a small puncture under local anaesthetic, and Radiesse may be placed where the floor has thinned. Narrow, deep corners are different. TCA CROSS places a microdroplet of strong acid into the corner, and laser then evens the surface. It is not used on wide, shallow boxcars. Release comes before resurfacing, and Radiesse does not lift a scar that is still tethered.
The sequence
Who this suits
Shallow boxcars, where a shorter recovery than the S3 is wanted.
Deep boxcars, including those that have plateaued after earlier CO2 or RF microneedling.
Darker skin, where less surface injury is preferred.
Reserved for the scars that truly need it, because post-inflammatory pigment risk is higher.
Narrow, deep corners of a boxcar, followed by laser to even the surface.
Boxcars held down by a tether, before any resurfacing.
Small, isolated, very deep boxcars, by referral to a plastic surgery specialist.
Who should wait or change the plan
It must be controlled first.
The plan changes until the skin has settled.
Timing is reviewed at assessment.
This changes the plan and is discussed before laser.
This is weighed before any resurfacing.
This is discussed at assessment.
These matter for subcision, so declare all medicines.
What treatment cannot do
Outcomes are not promised, and some boxcars improve less than others.
FSX Laser does not treat deep boxcars.
It does not ablate steep walls or reach a narrow, deep corner.
It is not used on wide, shallow boxcars.
Punch excision and elevation are referred to a plastic surgery specialist.
Risks and side effects
Less common risks are prolonged redness, pigment change, infection, a cold sore flare and a new scar. Fractional CO2 carries a higher risk of post-inflammatory pigment in Fitzpatrick III to V skin, which is why it is kept for scars that need it. Strict sun protection follows any resurfacing. Tell the clinic about slow healing or any change that worries you. Temporary darkening is the main concern in darker skin. Contact the clinic the same day for increasing pain, spreading redness or warmth, pus, or slow healing.
What recovery looks like
Redness settles. Fine scabbing can occur, and it should be left to shed.
Expect redness, swelling and warmth, then fine crusting and peeling.
A white frost appears, then a small crust that sheds.
Bruising and swelling are expected.
Sutures and wound care are set by the specialist.
Strict sun protection follows resurfacing, and crusts should be left to shed.
Sessions and fees
Treatment is staged, but no fixed number of sessions applies. Healing sets the pace. Your written plan covers the stages and fee factors after examination. Because most faces have mixed scar types, your plan may also draw on the rolling scar and ice pick scar guides, or on 4D Scar Reconstruction, which sets the order of each step. Because new lesions create new boxcars, acne care continues alongside scar care. Bring photos and records of any earlier scar treatment to your first visit.