Because the MRI machine is essentially a big, powerful magnet, the biggest safety concern is removing all ferromagnetic metal objects from the imaging area. The magnet is so strong it can pull oxygen tanks, wheelchairs, and any metal device implanted in the body.
The medical professional who oversees your MRI will ask for a comprehensive medical history, especially notes on any implants you may have before undergoing any procedure. The Radiological Society of North America provides a comprehensive list of metal components that doctors should check for before administering an MRI, from internal devices like pacemakers and cochlear implants to cosmetic items like piercings, jewelry, and even metallic nail polish.
The titanium, titanium alloy, and zirconia used in most dental implants are not ferromagnetic metals - making it perfectly safe to enter an MRI with them in your mouth. Even so, it's best to alert your doctor that you have dental implants if you need an MRI. Metal objects in the body can still interfere with imaging even if there is a slim chance that they will injure you. You should also tell your doctor about any metal fillings, crowns, braces, or dentures.
Dental implants and MRI technologies continue to advance, which is good news for patients who can benefit from both. Since most implants are MRI-safe, you don't have to worry that the dental treatment you're receiving now will limit your options for medical imaging later.