Very good question.
It depends on when your Lumineers were fabricated. If they were done within the past month, then it is likely that your original Lumineer can be repliated. However, if it has been more than a month, then most likely you will need it remade. Most likely, even if it has to be remade, it will be nearly identical to your original, I would not worry about that.
As far as removal of the remaining portion of your Lumineer, yes your dentist will need to drill it off. He can do this atraumatically, without affecting your tooth underneath, rather easily. Dentists are trained to do this for removal of any crown
. Normally, once the Lumineer starts to be drilled on, it will chip off rather easily with the use of a scaler by the dentist, instead of the drill. Keep in mind that the cement
underneath will need removal as well, but it can be polished off without traumitizing your tooth. This is very easy to do as well.
Overall, I would not worry about your situation, other than the fact that you will need to wait for a new crown to be made in the meantime.
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