If you aren't using any sort of tyrosinase-inhibitor while doing the
microdermabrasion treatments AND using a sunscreen ;), you really won't
see much in the way of lightening for the melasma. The
microdermabrasion will remove the upper layers of the stratum corneum
(which include the darker cells), but these dark cells are "born" in the
lower layers of the skin, approximately 28-34 days below the surface,
and you must basically turn off the melanocytes in order to reduce
future pigmentation problems.
Microdermabrasion CAN help the melasma because by removing the upper
layers of dead cells, the hydroquinone, kojic acid (or whatever skin
lightening product you use) can then penetrate down to the melanocytes
more rapidly and begin working. In general, if you use a skin lightener
only, you could see results in 4-6 weeks; used in conjunction with
microdermabrasion, you can see significant results in as little as 3
weeks.
HTH, Best,
Laura Root, CIDESCO Diplomate
Offices of Dr. Jeffrey J. Ptak
Phoenix, AZ
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