Victoria Rinando, DDS

It would have been more ideal to have made the necessary corrections made prior to cementing.  Minor adjustments to length and shape can be made after cementation, but only to a certain extent.  If further correction become necessary, you may need to have them remade.  It is too difficult to comment on the appearance based on your photo.  Any dentist should acquire your approval on the final appearance of the veneers prior to cementing.  I would return and discuss your concerns with your doctor.  Hope that helps :)

More information would be necessary for any dentist to diagnose, but if your current dentist suggested bone loss as the cause for your discomfort, he could be eluding to Periodontal Disease.  He should have recommended a treatment or provided you a referral to a specialist.

Adjustments at the time of crown cementation are more frequent than not.  Depending on why the fit needs to be altered the dentist has to make a clinical decision whether or not to adjust the crown, the adjacent/opposing tooth, or sometimes both.  Adjustments should not have resulted in decay, as decay (caries) can only be caused by carbohydrate, acid, and bacteria presence.  If a contact is not tight enough resulting in food trapping, or loose flossing, material needs to be added to the crown by the laboratory that fabricated it.  This should hopefully be detected before cementation.  If not, your crown will need to be removed and potentially re-made. Hope that helps :)