I had a surgery in January, which left scar tissue heaped up in my right nostril...I usually take MSM for my skin, but got lazy about my supplements, and didn't resume taking them until about two weeks ago. Within a week my nostril was remarkably flexible and the scar tissue was flattening and softening up. Turns out, MSM synthesizes the cross linking of collagen (scar tissue is just poorly formed collagen) so, in otherwords, it normalizes it.
Also, massage and pressure will help if the scar is elevated and hard. Apply medium pressure for a minute or more a day to help break up the scar tissue.
Of course, there are lots of cosmetic options available too....acids, microdermabrasion, injectables...