Differences between 11/12 and 15/16 Gracey

April 11, 2023
These instruments have been around for a long time, and which to use is still a topic of conversation. Hygiene Edge breaks down the differences.

Gracey instruments. You either love them or hate them. Even though they have been around since the 1940s, who’s using them and who isn’t is still a topic of conversation. I’ve worked with dental hygienists who love them and request them in every kit, and some who only pull them out when they have a tricky periodontally involved case with deeper pockets. What type of dental hygienist are you?

No matter which type of RDH you are, there are some big differences when it comes to the mesial Graceys—the 11/12 and 15/16. Here’s how they differ, and how they should be used.

  1. The 11/12 has fewer bends. The 11/12 was a previously designed in the earlier days of dental hygiene, back when dental hygienists wore skirts and stood up, and patients sat straight up during procedures. Now with years of research and findings, we know that ergonomics are critical for a long and healthy career, and patients should be lying completely back for the most ergonomic outcomes. With patients being positioned differently, we need a different instrument. And with that, the 15/16 was born. This instrument has a better bend for when we’re sitting; we can reach further back and have the terminal shank parallel with the tooth a bit easier.
  2. With the 11/12, you need to do a cross arch or extra oral fulcrum. Due to the bends being less dramatic, it’s so tricky to have a great fulcrum in the same quad with this instrument. Instead, try an extra oral fulcrum to ensure that the terminal shank and tooth are straight lines together, or parallel. The 15/16 can utilize a same arch fulcrum due to its design.
  3. With the 11/12, you may have to bend your wrist to get the terminal shank parallel to the tooth. Due to its straighter terminal shank, having a great fulcrum and a neutral wrist can be tricky. You might find you have to flex your wrist a bit, which in turn can cause work-related injuries or less scaling force. With the 15/16 and its design, you should be able to have a more neutral wrist.

To see both instruments in action and the differences between the two, make sure to check out our video. Out of the two, what instrument do you have in your office?

More from Hygiene Edge:

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How to scale a crown

Hygiene Edge was created from three dental hygiene educators who love both dentistry and education. With over 40 years of experience both in the education space and the dental field, Melia Lewis, Jessica Atkinson, and Shelley Brown love sharing their knowledge through helpful, short videos online, speaking, and working with amazing companies. You can find more information at Hygiene Edge, on YouTube (youtube.com/hygieneedge), and Instagram (@hygieneedge). Have a question or a tricky area? Let us know! We’d love to help.

About the Author

Melia Lewis, MEd, BSDH, RDH

With her love of health and education, Melia Lewis, MEd, BSDH, RDH, became an RDH in 2009. Since graduation, she’s worked in private practices in Canada and the US. She is currently an adjunct professor at Utah Valley University and works clinically with patients. She loves the field so much that she cocreated Hygiene Edge, an educational platform for dental professionals to learn new skills and techniques. She can be found at @hygieneedge and @meliardh and reached at [email protected].