What complication can arise from non-passive fitting of a bar in overdentures?

The correct selection highlights the risk of a bar fracturing when it is not passively fitting in the context of overdentures. A passive fit is crucial in dental prosthetics, especially for implants and bars, because it ensures that there is no unnecessary stress or strain on the components. When a bar is not correctly aligned or is subjected to excessive force during function, it can lead to excessive bending or torsion, which may ultimately result in a fracture.

In the context of overdenture prosthetics, a fractured bar can significantly compromise the integrity and function of the entire restoration, potentially leading to patient discomfort, the need for repairs, and additional dental interventions. The failure of component parts in a dental restoration like a bar can also affect the stability and retention of the overdenture itself, emphasizing the importance of achieving a properly fitting bar.

Other potential complications such as infection, implant failure, and occlusal trauma, while serious, are not directly linked to the specific concern of the bar not fitting passively. Instead, these issues may arise from different factors such as poor hygiene, excessive loading on the implants, or inappropriate occlusal relationships, making the focus on bar fracture particularly relevant in this situation.