What Can I Do for Coloration of Dermabraded Area?

Dermabrasion to treat a childhood scar on forehead about 1.5 yr ago. The scar is ~2" vertical, depressed in center and raised on periphery. Dermabrasion improved the scar >50%. The dermabraded area has noticeably lighter pigmentation. 41 yo, male, blue eyes, blond hair and a darker skin tone. Had the procedure done in fall, avoided UV and regulary used sunscreen to mitigate pigmentation changes. What else could I do? Would it be safe to expose area to sun? I tan very easily. Surgeon has retired.