A dental bridge is a fixed prosthetic replacement. This restoration consists of an artificial tooth (pontic) fused between two crowns that cover the natural teeth on either side of the gap (abutment teeth). The primary function of a bridge is to restore the ability to chew and speak properly, improve aesthetics, and prevent the remaining natural teeth from shifting out of alignment.
Intended Stability of Dental Bridges
Bridges are intended to be permanent, fixed restorations that function like natural teeth. Stability relies on secure attachment to the abutment teeth, which are prepared to receive the crowns. A strong, long-lasting bond is achieved by cementing the crowns onto the abutment teeth using specialized dental cement. This foundational support is essential for distributing the significant biting and chewing forces the bridge must withstand daily. The dentist takes careful impressions to ensure the custom-made crowns perfectly encase the natural teeth.
Primary Reasons for Bridge Failure
Despite their fixed design, a dental bridge can occasionally come out. The most frequent cause of failure is tooth decay developing underneath the crowns of the abutment teeth. Although the bridge material cannot decay, the natural tooth structure beneath the cemented crown remains vulnerable to cavities if bacteria infiltrate the margin. Decay weakens the abutment tooth, causing the crown to lose its secure seating and allowing the bridge to fall off.
Another common reason is the degradation or washout of the dental cement over time. The cement bond can break down, creating a micro-leakage gap that allows oral fluids and bacteria to access the underlying tooth structure, or simply reducing the retention force holding the bridge in place.
Physical trauma, such as a sports injury or biting down on an unexpectedly hard object, can exert excessive force that fractures the bridge material or damages the supporting abutment tooth. Chronic habits like clenching or grinding the teeth (bruxism) also place continuous, uneven stress on the bridge, which can hasten the breakdown of the cement or cause a fracture. Periodontal disease is also a factor, as it causes the abutment teeth to lose necessary bone support, leading to instability.
Immediate Action When a Bridge Detaches
If a dental bridge comes loose or falls out, remain calm and carefully retrieve the prosthetic. Gently clean the bridge with lukewarm water to remove debris; avoid scrubbing or using harsh chemicals. Store the bridge in a clean, sealed container to protect it until your dental appointment.
Contact your dentist immediately, as a detached bridge is considered a dental emergency. The exposed abutment teeth are vulnerable to further damage, decay, or shifting, and delaying treatment can complicate the re-cementation process. While waiting, rinse your mouth with warm salt water to soothe irritated gums and keep the area clean. Avoid chewing or applying pressure on the exposed teeth, and only use temporary dental cement from a pharmacy if your dentist specifically advises it.
Extending the Lifespan and Planned Replacement
With proper care, a traditional dental bridge is designed to last between five and fifteen years, though the actual lifespan is dependent on maintenance and the health of the supporting teeth. Longevity is significantly extended by maintaining meticulous oral hygiene, which involves more than just regular brushing. Specialized tools, such as floss threaders or interdental brushes, are necessary to clean thoroughly underneath the pontic, where a regular toothbrush cannot reach.
Avoiding sticky or overly hard foods, such as caramel candies or ice, minimizes the mechanical stress on the restoration and the cement bond. Routine dental check-ups are paramount, as they allow the dentist to monitor the abutment teeth for signs of decay or gum disease and check the integrity of the bridge.
In some cases, a dentist may intentionally remove an aging bridge to replace it due to material wear, a change in the bite, or to address new issues with the abutment teeth. This planned replacement is a controlled procedure that is part of the long-term management of the restoration, not an accidental failure.