TGF-α expression in SMG of group A1 and B1 at week 5. Longitudinal section of ductal epithelium of SMG under 10x magnification showing A, Control group (A1) with TGF-α intensity score of highly positive (4+). B, Experimental group (B1) with TGF-α intensity score of positive (3+). C, Control group (A1) with TGF-α intensity score of positive (3+). D, Experimental group (B1) with TGF-α intensity score of weakly positive (2+).