The Sphincter of Oddi consists of:

The Sphincter of Oddi is a muscular valve that controls the flow of digestive juices (bile and pancreatic juice) through the ampulla of Vater into the second pa of the duodenum. It is 10 - 15 mm in length, situated within muscular layer of media in the duodenum.It consists of sphincters at 3 levels: 1. Sphincter choledochus: covers the distal end of intraduodenal pa pa of common bile duct before it joins with the pancreatic duct of Wirsung. 2. Sphincter pancreaticus: located at the distal end of pancreatic duct. 3. Ampullary sphincter: covers the distal end of both the ducts after they unite to form a single common channel that opens into the duodenal lumen at an elevation called Ampulla of Vater.