The wisdom on the top never came out

So there was no extraction.

You said: 如果上面的已经拔了，下面这个没用，但很难清理到，容易出蛀牙，我会把它拔了。

What do you mean "下面这个没用，..."  ?

I really appreciate your response, as I am so nervous about this wisdom tooth.  If I had an extraction before, I probably would not have been so nervous.