MAJOR CONNECTORS

MAJOR CONNECTORS
A major connector is the component of the partial denture that connects the parts of the prosthesis located on one side of the arch with those on the opposite side. It is that unit of the partial denture to which all other parts are directly or indirectly attached. This component also provides the cross-arch stability to help resist displacement by functional stresses.
The major connector may be compared with the frame of an automobile or with the foundation of a building.

When using removable partial denture, the prosthesis must extend to both sides of the arch. This enables direction of functional forces to supporting teeth and tissue for optimum stability. This is most effective when a rigid major connector joins the portion of the prosthesis receiving the function to selected regions throughout the arch.
The chief functions of a major connector include
1- Unification of the major parts of the prosthesis.
2- Distribution of the applied force throughout the arch to selected teeth and tissue.
3- Minimization of torque to the teeth.
A rigid major connector will limit movement possibilities by acting as a counteracting lever. This phenomenon is referred to as cross-arch stability. Cross-arch stability becomes more important in situations associated with a high potential for greater prosthesis movement (distal extensions).
LOCATION
Major connectors should be designed and located with the following guidelines in mind:
1. Major connectors should be free of movable tissue.
2. Impingement of gingival tissue should be avoided.
3. Bony and soft tissue prominences should be avoided during placement and removal.
4. Relief should be provided beneath a major connector to prevent its settling into areas of possible interference, such as inoperable tori or elevated median palatal raphe.
5. Major connectors should be located and/or relieved to prevent impingement of tissue because the distal extension denture rotates in function.
The gingival tissue, on the other hand, must have an unrestricted superficial blood supply to remain healthy. To accomplish this, it is recommended that the borders of the major connector be placed a minimum of 4 mm away from and parallel to the gingival margins in mandible and 6 mm in maxilla.