Hello, Sorry about this problem of dentition. Yes, it is uncommon and needs observation. If this is regular premolar tooth, no problem but it has to be firm and not additional one to regular premolar.
And the incisor (top or bottom) has to erupt at regular time of 6-7 months.
If necessary, an X ray may be advised by dentist.
what do you mean not additional one to regular premolar
sorry about that, i didn't quite understand