Teeth problems in rabbits and guinea pigs, once started are often an ongoing problem. Their teeth constantly grow and are kept both the normal (correct) size, shape AND position through their normal chewing action on roughage type diets that are high in fibre, eg Meadow Hay or Timothy Hay (NOT lucerne or Oaten hay - they are too high in protein). A constant supply of this type of hay must be provided to ensure both a good diet, but also minimise teeth problems.
As soon as ANY dental (teeth and/or jaw) problems are noticed, IMMEDIATE action must be taken to correct it. If the problem is left untreated for only a short period of time, the position of the teeth actually move and no longer connect and wear against the opposite teeth, and allow uncontrolled growth and tooth length that then requires regular teeth trimming under a short anaesthetic.
Oral abscesses can also occur. These photos are of TURBO the guinea pig having enamel spurs on his molars (grinding teeth) burred off to allow him to eat and chew normally again! Note the equipment required to access such a small orifice! A guinea pig or rabbit anaesthetic also requires the constant attention of a theatre nurse!