Adjacent Dental Implants Classification Based on Restorative Design.

There is controversy in the literature regarding the indicated retentive mechanism for implant-supported crowns. When adjacent implants are restored, the restoration can be screw retained, cement retained, or a combination of cement and screw retained. Adjacent implant-supported crowns can be restored as individual implant supported crowns or can be splinted. A classification system is proposed when adjacent implants are restored. The classification system describes currently available options to restore adjacent implants. Six types of prosthetic design options are proposed as Class I through Class VI. In Class I design, individual cement-retained crowns are made. In Class II, individual screw-retained crowns are fabricated. Class III involves fabrication of individual screw-retrievable/cement-retained crowns. Class IV prosthetic design involves splinted cement-retained implant crowns. Class V prosthetic design involves splinted screw-retained crowns, and Class VI involves splinted screw-retrievable/cement-retained implant supported crowns.