A dental crown is a custom-made, tooth-shaped cap used to restore a damaged tooth’s shape, size, and strength. Crowns are made from durable, inert materials like porcelain, ceramic, gold alloy, or zirconia. Although designed to be permanently cemented, the adhesive can wear down, causing the crown to become loose and potentially fall out. Accidental swallowing, or ingestion, of a detached dental crown is a relatively common occurrence.
When a crown is lost, the primary concern is determining if it was swallowed (ingestion) or inhaled (aspiration). Ingestion means the crown has entered the gastrointestinal tract and will likely pass. Aspiration, however, means the object has entered the airway, which constitutes a medical emergency. Although the crown’s small, rounded shape often favors safe passage, its hard, non-digestible nature requires close monitoring.
Immediate Risk and Warning Signs
The most immediate risk is aspiration, where the crown enters the respiratory system instead of the digestive tract. An aspirated foreign body is statistically more likely to lodge in the right lung because the right main bronchus is wider and enters the lung at a less sharp angle. This blockage can severely compromise breathing and requires immediate medical intervention.
If the crown is intact, its smooth surface is less likely to cause localized injury. However, if the crown fractured or broke, the resulting sharp edges pose an increased risk of snagging or perforating delicate tissue as it travels. This risk exists whether the crown is in the airway or the digestive tract.
Anyone who suspects aspiration must seek emergency care immediately. Warning signs include persistent coughing, shortness of breath, wheezing, or chest pain. For ingestion, immediate danger is signaled by signs of impaction or perforation, such as severe abdominal pain, repeated vomiting, or difficulty swallowing.
The Normal Path Through the Digestive System
In the majority of cases, the ingested dental crown follows the path of food through the gastrointestinal tract without issue. Dental crowns are made from inert materials, such as metal or ceramic, meaning they are not affected by stomach acids and will not corrode or release harmful byproducts.
The digestive system is equipped to handle small, blunt foreign objects. Once past the esophagus, the crown travels through the stomach and into the small and large intestines. Transit time is typically between 24 and 72 hours, though it can take up to a week depending on individual motility.
Individuals are advised to monitor their stool until the object is recovered to confirm the crown has passed. Using a high-bulk diet may help ease passage by increasing stool volume and softness. Confirming its expulsion provides peace of mind, though recovery is not strictly necessary.
Potential Complications and Medical Procedures
Although most crowns pass uneventfully, complications occur in a small percentage of cases, necessitating medical intervention. The main risks are obstruction and perforation within the gastrointestinal tract, or continued impaction in the respiratory system. Obstruction is most likely at narrow points, such as the pylorus (the outlet of the stomach) or the ileocecal valve connecting the small and large intestines.
When a crown is suspected to be stuck, X-rays are the primary diagnostic tool used to locate the object. Crown materials are radio-opaque, meaning they show up clearly on the image. If the crown is lodged high in the digestive tract (esophagus or stomach), a gastroenterologist may perform an endoscopy. This procedure uses a flexible tube with a camera and tools to visualize and remove the object.
If the crown was aspirated into a lung, a separate procedure called a bronchoscopy is used to remove the object from the airway. Surgery is a last resort, required in less than one percent of cases. It is reserved for serious complications, such as intestinal wall perforation or obstruction that cannot be resolved endoscopically.