Accidentally swallowing a tooth, whether a baby tooth or a fragment of an adult tooth, is a common event, particularly in children or following a dental injury. While the immediate reaction may be concern, the human body is remarkably efficient at handling small, non-digestible foreign objects. Understanding the journey a tooth takes through the body and the potential risks can help alleviate worry and inform the proper course of action. This information explains the biological outcomes and safety considerations when a tooth is unintentionally ingested.
Immediate Risks of Swallowing
The most urgent safety concern occurs immediately after ingestion, as the tooth passes through the throat. Instead of entering the esophagus, a foreign object can inadvertently enter the trachea, or windpipe. This misdirection, known as aspiration, can cause the tooth to become lodged in the tracheobronchial tree, requiring immediate medical attention.
Signs that the tooth has entered the airway include sudden, persistent coughing, choking, wheezing, or difficulty breathing. If the tooth has sharp or jagged edges, it poses a mechanical risk before reaching the stomach. These irregular surfaces can scratch or irritate the delicate lining of the throat or esophagus, causing discomfort or minor injury. Any inability to swallow, neck pain, or persistent chest pain indicates that the tooth may be impacted in the esophagus and warrants immediate medical evaluation.
Composition and Digestive Interaction
A tooth is composed of some of the hardest substances in the human body, which determines how it interacts with the digestive system. The outermost layer of the crown, the enamel, is 96% mineral content, primarily crystalline calcium phosphate in the form of hydroxyapatite. Beneath the enamel lies dentin, a slightly softer tissue with a lower mineral content.
Once a tooth reaches the stomach, it encounters hydrochloric acid (HCl), which maintains a highly acidic environment (pH typically between 1.5 and 3.5). This acid is capable of dissolving mineral structures by reacting with the hydroxyapatite, a process known as demineralization. However, the tooth’s physical density and the relatively short time it spends in the stomach prevent substantial structural dissolution.
The acid will erode the outer layer minimally, but the tooth remains largely intact as it progresses into the small intestine. Digestive enzymes and bile are designed to break down organic materials like fats, proteins, and carbohydrates, not inorganic mineral structures. Consequently, the body cannot absorb the tooth for nutritional benefit, and it continues its journey virtually unchanged.
Monitoring the Passage and Potential Issues
After leaving the stomach, the tooth enters the intestinal tract, where muscular contractions known as peristalsis propel it forward. For most individuals, the tooth will pass harmlessly through the entire gastrointestinal system. The typical transit time for a small, blunt foreign object is usually between four and six days, though passage can sometimes occur in as little as 24 to 48 hours.
The tooth’s passage is generally uneventful, and it is expelled with stool. However, complications can arise, usually associated with the tooth’s size or sharp edges. A tooth can become lodged in narrower segments of the small or large intestine, leading to a mechanical obstruction.
Signs of potential obstruction or internal injury require immediate medical attention. These include severe, persistent abdominal pain or cramping, vomiting, fever, or the inability to pass gas or stool. The presence of blood in vomit or stool suggests a laceration or tear in the digestive tract lining. If any of these symptoms appear, or if the tooth has not passed within a week, consulting a physician is advisable for monitoring and potential imaging.