Of course I do try to estimate treatment time during the planning stages and be realistic about this, and in most cases I get it about right or slightly over-estimate. But it still doesn't stop the question being asked.
At the beginning of treatment teeth appear to move quickly. Towards the end of treatment the teeth can appear generally straight, and the changes will be mush smaller. Sometimes these can seem unnecessary to the patient, like getting that tooth 'just so' or trying to correct the bite. Patients often wonder why I'm spending time correcting something they are not concerned about.
Take the teenager I saw yesterday. His teeth look fabulous, they're straight and he's very happy with them. I'm concerned because the bite isn't correct, in his case the side teeth don't meet evenly and he doesn't have an obvious place to bite. I prescribed elastics to improve this, he'll need to wear them all the time to get the result, and this is the only thing that's left to correct, so if he wears the elastics well I'll be able to finish treatment in a few months. He wasn't exactly enamoured about wearing elastics, both for the appearance and the comfort of them and asked if he really needed them, after all, he's happy with the appearance now.
I find this a bit difficult as I think people perceive that I'm fiddling with the teeth for the sake of it and they won't get a real benefit, they'd rather finish treatment. It is certainly the detailing of the last few visits that makes a difference between a good result and a great result. Naturally I want to get the best result I can, at the end of the day I am the judge of my own treatments and I have high standards. But there's often more to it than that. Take the 'wrong bite' situation. Getting a good bite where the side teeth interlock nicely helps with long term stability, that's the teeth staying where I've put them. It prevents uneven wear on the teeth and puts less stress on the jaw joint and jaw muscles, which might cause problems later.
Will he wear his elastics enough? I'm not sure, but he's been informed why it's important and I hope he will successfully complete treatment. I really don't prescribe elastics (or any other form of treatment) for a joke, they are necessary in some cases, so please listen to your orthodontist and follow their advice, and ultimately, trust that all they are trying to do is get the best possible result. Isn't that worth a few extra months wearing braces?
