The key to everything is as Beeson says approach calmly the other coach, parents or even the ref if you are a coach. The quickest way to get the cold shoulder or even worse calls in later matches is to be aggressive in your explanations or complaints to the ref.
Kolton has only been bitten one time and it was last year. The ref didnt see the bite happen, but showing him the bite mark he awarded Kolton 1pt and warned the other kid. The other coaches came over before the next period started and apologized and gave Kolton words of encouragement to continue on his already well wrestled match. I was impressed and very satisfied with everybodys resolution of the situation. Had it not been a 6u match I was told it would have resulted in a DQ for the kid not just a warning and point.
We as parents and coaches need to remember that even when we are amped up in the heat of the moment, we still need to lead by example.