I think you should go for a mixed approach of orthodontics and crowns ... chk if but having deep bite which is leading to ur present spacing between teeth

Going only by the description that you have mission and without a look at the clinical condition of the area, the most appropriate suggestion that we can give you at this point is to go for a proper clinical check up because it seems most likely that you are suffering from gingivitis leading to gum recession. The caps on the Teeth do not change their shape or size with time and it is the soft tissues like gums which show degenerative changes that time and lead to spaces between the teeth whether natural or prosthetic. The right treatment options can be explained only after a proper clinical evaluation and you should not delay your visit to the dentist. Regards

It seems your crowns need replacement .