If a dog's nails are allowed to grow, they will curl over into a spiral shape; walking will become increasingly painful to the dog as they grow, putting pressure on the dogs toes (a bit like walking in shoes that are too small). Uncut nails may curl so far that they pierce the paw pad, leading to infection and debilitating pain. By not trimming your dog's nails on a regular basis the quick (vein) will grow to the length of the nail, making it nearly impossible to cut properly.
We also offer a nail grind which is done with a Dremel tool specifically designed to grind the dog's nails. It allows the nail to be trimmed down close without hitting the quick.