Nipping horse

["lkgower" <jazena@kelp.net>]

Hi all,  Could you help me with a problem with  my 4 1/2 y.o. gelding?  He nips, chews and holds things in his mouth, like the shank on the bit, the lead rope, the reins, my stirrups, anything he can get his teeth on.  The vet checked him last month and said he would need to have his teeth floated in about 3 mos.  He grabbed my hat off my head today, and I have to be careful or he will nip my hands arms etc.  I know this can become a dangerous habit, so what do I do to correct it???  I have slapped him under his chin so he won't see me do it, but it doesn't seem to be working.  He was gelded about 9 mos. ago and I wonder if it is just left over hormones.  Help please!!

Lindak and AAce