You get a shot to make it numb, don't you? If so just close your eyes and think about riding your horse, lesson, what to improve, etc. while he works on your teeth - something to keep your brain occupied.
BTW, I read that you want to brush your teeth -at least- 2 mins twice/day for the paste to work.
"Life isn't about waiting for the storm to pass: it's about learning to dance in the rain..."
"When we are no longer able to change a situation - we are challenged to change ourselves."
"How people treat you is their karma; how you react is yours."