same here, once a year...
The point of checking every 6 months is to catch problems before they get serious. Being prey animals, horses have evolved to hide pain until it is severe (because it makes them weak and look tasty to predators) so it is up to us to make sure we catch problems early.My dentist(very highly qualified) also said that it is better for a horse to be done consistently for 2-3 years and then checked the next year and only done if necessary.