Bar systems may be utilized for overdentures, removable partial dentures, and implant prosthesis. Bars may be rigid or resilient, permitting free movement of the prosthesis to direct forces away from the retaining abutments to the supportive bone and tissue. Bars provide more stability and retention than studs with the additional benefit of abutment splinting. 

Bar systems are generally in one of three types:

1. Direct Retainers, such as the Hader or Dolder bar systems
2. Incorporated into the bar, such as Locator® or Clix bar attachments.
3. Offset attachments, such as the Plunger Loc, Sagix, or Vertix.

The shape of the bar is indicated by the amount of room available, by the shape of the alveolar ridge, and the type of construction. Do not engage labial soft tissue undercuts with the denture base flange, as this will alter the path of insertion and cause excessive wear and servicing requirements.