Evaluation of myofibroblast orientation in WT and Mmp13−/− mouse granulation tissue.

Sections of experimental granulation tissue of wild-type (WT) and MMP-13 knockout (Mmp13−/−) mice were stained for myofibroblasts with α-SMA antibody and analyzed for myofibroblast orientation. Scoring: +, weak; ++, moderate; +++, strong. Scoring is based on the parallel orientation of myofibroblasts to the implant surface where weak implies negligible orientation, moderate implies lining of occasional myofibroblasts in certain areas, and strong indicates intensive parallel lining of myofibroblast masses. Statistical significance (p) was determined by Pearson's χ2-test. n.s., not significant.