When a substantial tooth structure is lost a crown might be appropriate to prevent it from further break down.
Filing a tooth to receive a crown requires certain skills and knowledge. Tooth preparation requires certain knowledge and skills, just like carving or painting. You can imagine not all the artists are the same so their work may also vary quite significantly. That can be a reason why a dental crown may look real and stay on the tooth for several years and another one look fake, or a dental crown can stay in for several years without any complications while another one keeps coming off every year. Has it ever happened to you that your crown keep coming off and you need to have it re-cemented? Many people may think that is their fault, or it is related to what they eat and generally speaking it is considered normal, but the truth it is not normal.
As a prosthodontist, I leaned what needs to be done to minimize the risk of a crown coming off or get de-bonded. The key to have a successful crown lies in its design and incorporation of engineering principles to provide adequate stability and the skills to execute the task. One may think, this is something that all dentists should know, but the reality is, even though it is expected, that is not what is happening in the real world.
Also, when it comes to aesthetics, the skills of both dentist and technician who gets directions from the doctor matter a great deal.
By clicking on this link you can see the comparison of two dental bridges. One looks so fake that every one can recognize they are not real and the other one is so real it is hard to believe they are fake.
Matching the shade, shape and texture of the crowns to be made requires many steps and skills and attention to details.
If you can imagine all the cars are the same, all the stakes are the same, all the watches are the same, etc, then you can expect all the crowns or fillings are also the same.