The Physics of Dental Implants

This summer I worked at a dental office and often assisted the periodontist who places implants regularly. Placing an implant requires knowledge of physics because torque and other concepts of rotational motion are important in order to successfully place an implant that will last. I recall one patient receiving an implant that was knowledgeable about torque and physics. He was very interested in the instruments and the procedure. Force, lever arm, and perpendicular angle are the key aspects related to torque. Each of these is evident in the placement of implants.

The below video demonstrates how a dentist might use a tool to insert or remove an implant.

https://youtu.be/x7kPtwFCDx8?t=54s

However most often, dentists use high speed handpieces to place implants.

https://www.youtube.com/watch?v=_wGvcbJXX2s

Based on what we know about torque, it is clear that the torque of the high speed handpiece is important to properly place the implant. The special drill designed for each implant ensures there will be enough forces to keep the implant in the bone when the implant is placed. Each implant has specific torque guidelines that dentists must understand when they operate their high speed handpieces and choose the rpm for the selected drill and implant. We know: Στ = Iα. The speed of the handpiece is relevant because the α, angular acceleration, is also important.

This video also demonstrates the importance of rotational motion because each step of the way requires the high-speed handpiece in order to create space in the bone to place the implant. Handpieces often have speeds between 250,000 and 450,000 rpm.

It is important that the implant is sturdy and long lasting for safety and customer satisfaction (no one actually likes to go to the dentist…). The successful placement of an implant is actually a several month process that includes many steps depending on if the patient has bone loss in the area and if the implant is a good fit.  

Dentistry and dental instrument design are great examples of careers that involve physics in the interest of better human health.