TYPES OF IMPLANTS

ENDOSSEOUS IMPLANT

Endosseous implants are by far the most common type of implant placed today. Implants are placed directly into the mandible or maxilla . A pilot hole is drilled into the alveolar or basal bone beneath (in cases in which the alveolar bone has been partially or completely resorbed), and the implant body is inserted into this site. The top of the implant is positioned so that it either protrudes slightly through the cortical plate or is flush with the surface of the bone. Typically a superstructure containing a prosthetic tooth or teeth connects to the implant body through an abutment that is screwed into the body directly through the mucosa.

SUBPERIOSTEAL 

The subperiosteal implant-a design whereby a metal implant framework rests directly on top of the bone, underlying the periosteum, and provides attachment posts, which extend through the gingival tissue for prosthesis anchorage.

TRANSOSTEAL

Transosteal Implants. The transosteal implant (also called a mandibular staple) is used to support a mandibular denture when the patient has severe resorption and lacks enough bone support for endosseous or subperiosteal implants.

 A transosteal implant is the least common and most expensive type. It runs all the way through the bone. Inserting this type of implant is the most invasive of all implant procedures: the dentist drills straight through the mandibular jaw to bolt a plate onto the bottom of the bone.

Osseointegration and Biointegration

A major issue for implant design is the development of materials that are physically and biologically compatible with alveolar bone. Ideally, bone should integrate with the material, substance, or device and remodel the bone structure around it, rather than responding to the material as a foreign substance by encapsulating it with fibrous tissue. Under optimum circumstances, bone differentiation occurs directly adjacent to the material (osseointegration). Ideally, this osseointegration provides a stable bone-implant connection that can support a dental prosthesis and transfer applied loads without concentrating stresses at the interface between bone and the implant.