Why did my dentist miss the decay on my tooth if I come in twice a year?

A patient the other day asked me this question before we were ready to do a couple fillings on him. I get this question in a few different ways. It may come out as, why did your associate not see this last time? Or, I just had x rays last time, was it there then? Or, did this grow in 6 months? Or, if a new patient, I just went to my last dentist and I did not have any cavities!
This is a somewhat complicated situation to explain in fewer than 175 words. However, I will give you a brief explanation and if you need more detail please email me from my website or talk with your dentist.
First, a cavity can only be seen on an x ray once it has dissolved 20-30 % of the tooth structure so it may not have been obvious last visit. And cavities can grow fast on some patients!
Second, some teeth have rotations and mal alignments that cause cavities to be very elusive from standard x-ray positions.
Third, determining when to drill or not to drill is an art and science based on years of experience. It’s not black and white. 10 dental school professors would give 6 different potential cavities based solely on x-rays. Experience counts!
Fourth, honestly, sometimes it could have just been missed. We are not perfect and at times we overlook a cavity. When that happens I just fess up. It’s not negligent, it’s just human. That is why we try to take them every 6 months and both hygienist and Dentist look at x-rays to help the dentist diagnosis suspicious areas.
And lastly, ideally I would like to take 10-14 x-rays every 6 months to make sure I see every inch of a every tooth. However, “your” insurance carrier would not cover that so your out of pocket expense would be much greater. And honestly, most patients would be pissed off. So we try to stay with the 4 back x-rays and 2 front x-rays twice a year because that is all that is allowed. I hate to say it’s the game we all play but realistically, most people accept what an insurance company allows.
For more information please call 302-999-8113 or go to my website, DrEmmi.com