Overdenture prostheses are removable prostheses that rest on a small number of remaining implants or natural teeth in the jaw, supported by snap-like components. Locator retainers are small, cap-shaped pieces that are independently attached to each implant. In mechanical load distribution, chewing forces are directly applied to that single implant; since there is no connection between the implants, their ability to balance horizontal loads on the implants is limited, which is why they are preferred in cases with good bone quality. Bar retainers, on the other hand, are systems that connect implants to each other in a bridge-like manner with a thick cast metal bar. Mechanically, the bar system distributes all uncontrolled horizontal and vertical forces during chewing homogeneously to all implants along that metal line (splint effect). It reduces the load on the implants, but cleaning them is much more difficult for the patient compared to the locator system.
