Sounds like you have a very proficient and conservative dentist, most people would rather that than having unneccesary work done. He checked each tooth in turn and then gums...so sounds like he gave a thorough check to be honest. These dentists are trained for longer than doctors, they don't need to closely inspect for ages to know if something looks right or not, they are HIGHLY skilled. 2 fillings in 8 years would depend on how well you clean your teeth and gums, what you eat and assorted other issues like your age/smoker/tooth grinder etc. Some people would need no work in 8 years, some people would be in such a mess that extensive work would be needed.
DId you mention this one tooth to the dentist? If it is slowly rotting away it will be really really obvious, black/grey and crumbling...even a dentist with 1 day of training could see that!
The hygienist is there to do tooth cleaning and gums health, not to assess the teeth as such. My hygienist will answer questions and says she is trained for simple fillings, but will refer you back for the dentist if anything occurs that is of concern. However, before you start your clean...why not ask if she thinks a full dental xray would be a good idea? My dentist does a full set every few years. Was this a dentist you know and trust and have been to before? I think you should explain your fears to the hygienist that you are worried about how strong certain teeth are, they can quickly put your mind at rest on that by putting a probe against it and checking the enamel and dentine strength.
The great thing is....you went....and went and got checked and had some routine work done. Some people don't take the bull by the horns and even do that. The important thing now is to keep attending those routine checks, as this is when they can keep a continuity check on tooth changes. The other great thing about teeth is that providing you look after them fairly well, and the gums of course, everything else can be 'put right' that arises.
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