Phencyclidine (PCP) was originally developed as an anesthetic, but the adverse side effects prevented its use except as a large animal tranquilizer. PCP acts as both a depress â¦ ant and a hallucinogen,and sometimes as a stimulant. It is abused primarily for its variety of mood-altering effects.
1 An inlay- As the name suggests, this restoration sits inside the tooth.  An onlay- In contrast is bonded on top of the tooth, replacing some or all of the cusps of the tooth.
Porcelain Inlays and Onlays. 1  If you have large metal fillings that you want replaced or larger cavities that you want to make look more natural and function more like your natural teeth, you may want to consider porcelain inlays/onlays.