This often resulted in the tooth breaking, causing jaw fractures and soft tissue damage.
The original design featured a straight shaft, which caused it to exert pressure on the tooth next to the one being extracted.
Newer designs, such as those manufactured by medical instrument maker Charriere featured interchangeable claws.
By the end of the 19th century, the introduction of forceps made popular notably by Sir John Tomes, rendered the tooth key mostly obsolete.
However, a modern version of the dental key, the Dimppel Extractor, briefly revitalized its use later in the 20th century.