A US Food and Drug Administration (FDA) advisory committee panel overseeing dental products recommended yesterday the reclassification of blade-form endosseous dental implants, also known as blade- or plate-form implants, from a Class III, "high risk" medical device regulatory status, requiring premarket approval, to a "medium risk," Class II, with special controls as provisions for the marketing of the implants.
The FDA's Dental Products Panel itself proposed the reclassification in January, and the agency says it has gathered sufficient evidence demonstrating the implants to be acceptably safe for the reclassification.
"Since the time of the panel recommendation, sufficient evidence has been developed to support a reclassification of blade-form endosseous dental implants to class II with special controls," the agency said in a statement.
Known risks of the blade implants include local tissue or existing dentition degeneration due to excessive mobility, nerve impingement-related pain, bone or nerve damage, infection, adverse tissue reaction, and migration or thermal injury.
However, the agency notes that the implants' track record suggests a safety profile suitable for Class II regulatory status.
"The FDA has been reviewing these devices for many years and their risks are well known. A review of the applicable clinical literature indicates that the device has a high success rate (remaining implanted/not removed) and that few relevant adverse events have been reported in the case of these devices or related devices suggesting that the device has a high long-term safety profile," the statement said.
The special controls required for the change include design requirements, mechanical performance (fatigue) testing, corrosion testing, magnetic resonance environment compatibility, biocompatibility, sterility testing, technological and patient labeling, and documentation of clinical experience, including adverse events.
The blade-form implants, shaped like small rectangular plates or razors, date back to the 1950s, when they were made of stainless steel, and they were in fact among the first endosseous implants to be developed.
But the screw-shaped titanium implants of the 1980s ushered in a new, more user-friendly era of implant dentistry, explained Nicholas Caplanis, DMD, MS, president of the American Academy of Implant Dentistry.
"The screw-shaped implants that were introduced in the 1980s were more systematic and easy to place, so companies stopped making the plate-form implants as much," he told Medscape Medical News.
The primary benefit of the blade-form design is to allow implants in areas of the jawbone that are thin and unable to support the bulkier screw-shaped implants.
If blade-form implants are not used, dentists will typically need to perform an augmentation bone graft procedure to build up enough support for the screw-shaped implant, which is more time consuming and costly.
The original drawback of the blade-form implants, however — greater difficulty in placement — has remained their biggest challenge, and the regulatory reclassification is not likely to change that, Dr. Caplanis said.
"I think [the reclassification] will open the door for the major corporate players in implant dentistry to start looking at that design again, but because plate-form implants are more technically demanding to place, I'm not sure if we're going to see them flourish or become a major device," he said.
"But I do think that if some major manufacturer came up with a more systematic kind of surgical kit for placing these, then some of the more advanced practitioners will start to place them again," he said.
Dr. Caplanis has disclosed no relevant financial relationships.
Medscape Medical News © 2013 WebMD, LLC
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Cite this: FDA Panel: Reclassify Blade-Form Dental Implants - Medscape - Jul 19, 2013.