Which statement about bar overdentures is false?

The statement regarding the engagement of the implant bar with the internal hex of every implant in the restoration is false. In the context of bar overdentures, the implant bar does not necessarily engage the internal hex of all implants. Instead, the design of the system allows the bar to be secured to the implants through specific components, which could include screws or other attachment mechanisms that do not require the bar to directly engage the internal hex of each implant. This flexibility in design is crucial for providing a stable and properly aligned prosthetic solution.

Understanding this facet of bar overdentures is important because ensuring the proper connection and fit between the bar and implants is vital for the long-term success and functionality of the restoration. The other statements about needing a passive fit, adequate spacing between implants for components, and attachment methods are based on established protocols for ensuring the effectiveness and longevity of dental implants and their associated restorations.