Bone Loss over the Life of a Dental Implant: Open Discussion

According to Albrecktsson's established criteria for implant success, marginal boneloss post-loading should be less than 1.5mm the 1st year and on-going annual boneloss less than 0.2mm. He probably based this mostly on the earlier and still crappy NobelBiocare/Branemark implants. To maintain the marginal bone, the type of implant, sound surgical and prosthetic protocols have significant impact. I like the classic Straumann Standard tissue-level implants with the 2.8mm smooth collar supra-osseous for posterior teeth. Platform switch with morse-taper connection implant (Astra) for anterior teeth. Angulation of the implant for axial load and depth of the implant (not so deep during immediates) are also significant. These combinations give me on average better results interms of maintenance of marginal bone and certainly within the limits of Albrecktsson's classic criteria for implant success. Sloppy prosthetics like cement retention, open margins, deeply placed abutment margins, crappy crowns, excessive occlusal load, etc. also contribute to marginal boneloss overtime.

Not always so , whilst there are numerous reasons for possible bone loss over a period of time it is not an accepted fact . A group of us have noticed a consistent gain in bone height over the first few years of loading when using synthetic grafts and placing at the time of grafting even in cases where an adjacent implant in solid natural bone may show a small loss . There is so much we do not know it makes generalising any fact impossible. This has been noted over hundreds of cases so interesting and I have shown it often, is it worth doing some research , probably not , just more confusion as the biggest variable patient physiology is unpredictable Regards Peter

3 month recalls, good home care, night guard, proper occlusion. Treat the problem before it gets worse.

I have to strongly agree with Peter on this one. While we see bone loss on almost all of the older implant designs, I have been astounded by the OPPOSITE effect on some new implant designs. While implants that are placed at crest may show varying positions of bone levels, I am amazed at the increase in bone levels where implants are deliberately placed supracrestal. We measure these cases periodically over several years and find that this phenomenon continues throughout this time, including bone growing up to the abutment. There is a common thread on this one: a bioactive implant surface, low torque placement, low abutment microleakage, and medialized platform. The concept that we must accept crestal bone remodeling (net bone LOSS) is nothing more than mythology. Old paradigms do die hard. RJM