My mom isn't getting our dog shaved?

Right now, his fur is COMPLETELY covered in mats. At first, it wasn't bad and we would brush him occasionally. But for some reason she's gotten the idea that just cutting his fur on her own solves the problem. All she's doing is trimming down the mats! I hate seeing my dog like this....you can barely pet him without stroking mats of hair. What do I do? I've been at this for 2 years, I've told her that irritated skin lies beneath them,we cant tell if he has ticks, etc.