A 76-year-old man in Japan was eating inari sushi when he swallowed part of his denture. Ten days later, he arrived at the hospital with persistent pain in his upper abdomen and a worry that the missing piece was still inside him. A CT scan of his chest and abdomen showed no sign of it.
It was there all along. When doctors passed an endoscope into his stomach, they found the darkened resin appliance resting in the middle of the organ. Physicians at Asao General Hospital in Kawasaki and a Tokyo dental clinic described the case Aug. 13 in Cureus, and it highlights a quiet trade-off in modern dental work: a denture without metal can be very hard to see once it is swallowed.
A Careful Scan That Still Came Up Empty
The appliance was a non-clasp resin partial denture, about 1 by 3 centimeters, made without any metal. The man’s non-contrast CT was reconstructed in three planes and interpreted by a board-certified radiologist. It showed no definite foreign body inside the digestive tract and no signs of perforation or blockage. On exam, he had only mild tenderness in his upper abdomen.
A negative scan could easily have ended the search. Instead, the team weighed his reliable account of swallowing the denture and his ongoing pain, and ordered an urgent upper endoscopy.
Getting the denture out took two tools. A retrieval net alone could not pull it past the laryngeal inlet, the narrow opening at the top of the airway, so doctors added grasping forceps and completed the removal through the mouth without complications.
The authors concluded that a negative non-contrast CT does not rule out a retained radiolucent denture and that early endoscopy should be considered when suspicion remains high. They also noted that dental researchers have long recognized that conventional denture acrylics can be hard to see on X-rays, which has driven work on more radiopaque formulations.
Metal Makes Dentures Visible, but Not Necessarily Safer
Most denture bases are made of polymethylmethacrylate, a plastic that X-rays pass through easily, and only metal frameworks, clasps, or wires reliably show up, surgeons at Alexandria University in Egypt wrote in a January report on a jejunal perforation. They added that dentures with metal frameworks have a higher reported rate of impaction and perforation.
Their own patient shows why visibility is not the same as safety. The 70-year-old man swallowed part of his denture and went to the emergency department twice, three and five days before his final visit. Non-contrast CT scans on those visits did show the denture in his small bowel, thanks to its metal component, with no sign of blockage. By day 10, he had diffuse abdominal pain, vomiting, and constipation. A contrast-enhanced CT revealed an obstruction, and emergency surgery found perforations in his jejunum, the middle part of the small intestine. He recovered after part of the bowel was removed.
Metal-free dentures have misled doctors in other ways. In a 2024 report in Oxford Medical Case Reports, a 78-year-old woman in Tehran who had swallowed an acrylic partial denture developed worsening trouble swallowing and an ulcerated lesion that was first misdiagnosed as esophageal cancer. A CT scan and repeat endoscopy revealed the denture. In a case from England, a 79-year-old man had surgery for what looked like sigmoid colon cancer, but pathology found only inflammation around an impacted dental prosthesis.
Most Swallowed Objects Pass, but Dentures Can Lodge
Swallowing a foreign object is usually less dangerous than it sounds. The American Society for Gastrointestinal Endoscopy’s guideline on ingested foreign bodies says 80% or more will likely pass without intervention. The same guideline notes that adults without natural teeth are at greater risk of swallowing foreign bodies, including their own dental prostheses, and that trouble tends to occur where the digestive tract bends or narrows.
When dentures do lodge, removal can escalate quickly. In a 2020 report in the Journal of Medical Case Reports, a 47-year-old woman in Iran swallowed a dental prosthesis that X-rays did not show. Endoscopy found it wedged in the duodenum, the first part of the small intestine, but could not pull it free, so surgeons opened her abdomen, pushed the denture back into the stomach, and removed it there. The authors, who noted that dentures account for 4% to 18% of swallowed foreign bodies, recommended that old and worn dentures be rebuilt and redesigned periodically.
The Japanese patient was fortunate by comparison. His denture never left the stomach, where an endoscope could reach it, and it had caused no perforation by the time it was found.
A Clear History Made the Difference
The case was solved largely because the patient knew what had happened and his doctors trusted his account over a reassuring scan. That is much harder when a person does not notice a denture is missing or cannot describe it, as can happen with dementia.
People who wear partial dentures, and those who care for older adults, can help by noticing when an appliance goes missing and telling clinicians right away, including whether it contains metal. Loose or worn dentures are worth raising with a dentist.
Anyone who believes they have swallowed a denture, or who develops trouble swallowing, chest or abdominal pain, or vomiting afterward, should seek prompt medical care. A normal scan does not always mean the object is gone.
Key Questions Answered
What happened to the 76-year-old man?
He swallowed a metal-free partial denture while eating. Ten days later he still had upper abdominal pain, and after a CT scan showed nothing, doctors found the denture in his stomach with an endoscope.
Why didn’t the CT scan show the denture?
The denture was made of resin with no metal. Plastic denture materials let X-rays pass through easily, so they can blend in with surrounding tissue on imaging.
How was it removed?
Doctors used an endoscope with a retrieval net and then grasping forceps to pull it out through the mouth. There were no complications.
Are metal-free dentures more dangerous to swallow?
Not necessarily. Dentures with metal frameworks have a higher reported rate of impaction and perforation. The trade-off is that metal-free dentures can be harder to locate if swallowed.
Do most swallowed objects need to be removed?
No. Endoscopy guidelines say 80% or more pass on their own, but dentures can lodge in the esophagus, stomach, or intestines and sometimes cause perforation.
What should someone do if they think they swallowed a denture?
Seek medical care promptly and tell clinicians exactly what was swallowed and what it is made of, even if an initial scan looks normal.
Published by Medicaldaily.com
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