Hello, according to your question and my years of experience, there are only two possibilities. First, your polished teeth may have been damaged to some extent by improper operation by doctors, which may have caused pulpitis or gingivitis. It can't be ruled out that the decayed part of the teeth will form cavities in your porcelain braces, so you will feel the smell and smell of metal! Secondly, is the titanium porcelain tooth he gave you really a titanium porcelain tooth? Titanium porcelain teeth are made in strict accordance with the technical structure of human bionics! There are many kinds of porcelain teeth, the price ranges from 150 to 5000, and the processing cost is different! So I want to know if your attending dentist is a qualified dentist! If a standard titanium porcelain tooth is impossible! Therefore, it is necessary for you to go back to your attending doctor for re-examination and determine the treatment! Thank you. I hope it helps you!