[cypher]

Does he bite often or was it just a one off? If he doesn't normally bite then it could just be that he could smell something on your hands or something may have scared him a bit, they can often pick up on things we may not even be aware of.
Were you handling him in or out of the cage?

Highly unlikely to have anything to do with whether or not he uses his chews, they don't actually need chews if they have a proper diet & many don't like things sold as chew toys but whimzee dog chews are always worth a go if you haven't tried those, most hams love them. The small toothbrush one would probably be best.