If the black leathery part of the pad is torn through to the soft inner part, then yes take them to the vet.

This portion of the pad does not heal by itself just due to the toughness of the skin. It requires a thorough cleaning and suturing. If it doesn't, it can cause your pet to start walking funny, adding strain to other muscels and bones compensating for the injury. You also risk greater infection probabilities due to the improper closure of the wound.

Keep it cleaned and bandaged for now, but get them to the vet as soon as you can Please.