There is no problem with a gap between the bridge and the gums as long as you can keep it clean. But if it is in an area where it becomes a cosmetic issue, it needs to be addressed by a dentist.
Veneers need the same attention as natural teeth in terms of hygiene and regular cleanings. If your veneers are damaged, you can get new ones made and applied fairly quickly.
Anthony Mobasser, DDS, DMD - Account Suspended says:
Drugs such as cocaine, does not damage the restoration itself ( such as veneers or dental lumineers), however it does cause dryness of your mouth, in which that can cause damage to the supporting structure of your teeth, roots, and gums by causing decay, and periodontal problems, besides the...
