I was very pleased to see the article "Using a Removal Loop to Prevent Aspiration of Indirect Restorations" by Dr. Daniel B. Feit (May JADA).
During attempted cementation of a crown on an implant in 1994, the crown dislodged with a "snap" during removal, bounced off the torus palatinus and landed by the larynx. While our local anesthesia department was attempting to remove it, the patient coughed and the crown was gone.
Luckily, radiographic examination located it in the stomach. A week later it was sterilized and cemented!
The surgeon who helped in the attempted retrieval suggested a removal loop. I have been using them ever since. It is to Dr. Feits great credit that he started this practice under better circumstances than I did!