In a large crowd, the total number of teeth of all people combined divided by the total number of heads. In a well eduated crowd with
reasonable oral hygene, one would expect the tooth to head ratio to be close to 32:1. If you were to attend a
monster truck rally or a
wrestling match, one would expect the tooth to head ratio to be around 12:1. At a bluegrass concert it can sit around the 5:1 or 4:1 area.