[Laura-Lee]

Sounds like the problem resolved itself but as far as teeth go with horses, they can develop hooks and sharp points that periodically need to be filed down. These sharp edges cut the tongue and or inside of the cheeks making eating difficult and painful. To remedy this will require a haul in to the vet or farm call. I don’t know anyone who does this themselves. Most vets sedate the horse and use a drill with a file attachment to smooth out the teeth. The vet will want to do this once a year or more depending on the horse.

Worming would be another guess if he was losing weight. Or hay quality.