Bone Quality and Surface Coated Implants: What’s the Relationship?

Generally coated Implants are more costly so only used when needed , that is in poor bone quality sites . I use Dio Bio-tite H , Cap coated Implants and the Osstell system to measure the ISQ to monitor the percieved benefits. There was a systemic review of coated Implants in a very recent JOMI , so look it up for information as well as read the papers by Jimbo . We have seen some benefits with earlier loading but as to Bone density assessment on the Implant surface area the only way to tell would be a Syncotron CT scan , and as there are only I think 3 in the world it will be an expensive excercise. Peter

actually it was lekholm and Zarb back in 1985 that first described bone quality and quantity, not Misch, so let's give credit where credit is due. Secondly, what do you mean by surface treatments? back in the day, that meant titanium plasma spray or HA. These "coatings" are not used any more. What we have now are surface "treatments" like acid wash, titanium blasting and the integration of nano particles of various materials into the surface treatments for more dependable bone apposition and "quicker" integration. These treatments have led to greater implant success in softer bone. The additive coatings of yore worked better in softer bone because they made the implants slightly larger and therefore created more initial stability. However, it made these slightly oversized implants more difficult to place in denser bone since the bone did not compress as easily, so machined titanium implants were generally recommended for denser bone. Conversely, new generation implants have surface treatments that are subtractive in nature so these implants can easily be placed in all types of bone.

I do concur with both answers posted before. Although I do have some notes, Coating? like Ha or TPS wre used to increase oseointegration speed, the first by chemically atracting cells and the second one by incresing (inmenselly ) the contact area. There are other coatings like Endopore pressure fit implants that have a "3D" treated surface that makes bone grow into the implant (love them, great for single implants, no chance of inmediate loading though) same idea with the new zimmer trabecular surface. The disadvantage in hard cortical bone wasnt really the "oversize", it was that very cortical bone lacks cells compared to trabecular bone and so you dont really get and advantage using them. Also added coatings are very,very technique sensitive, and if exposed or contaminated they usually are lost( cant clean the surface and you get big bone destruction arround them). Also you get dull thread edges so they are harder to get in cortical bone. Hence the tendency for substaractive treatments that allow for a sharper shape. In my humble opinion, more than getting into coating or surface treatments, in hard bone is more important the macro design of the implant. Very aggresive square threads like isarely spiral implants type are hard to use beacause the have to much friction (one may cause compressive necrosis)and so one needs to go one or even two sizes bigger in the osteotomy. There are other types with less frictioning threads and more paralel walls that work just fine. Having said that, I use spiral implants in most of my cases, just need to be careful of the torque applied and if you get an ostell is even better.

I agree with much of what has been posted thus far. One important point not listed is that multiple studies show a greater bone to implant binding with HA coated implants. Many have worried about bone recession and exposure of HA and hygiene issues. One company (Implant Direct) makes an HA coated implant that leaves the coronal 3-4 mm uncoated to eliminate the recession and hygiene issues. There is no surface that performs better in poor quality bone than HA. I have replaced some failed implants in poor bone with these coated HA implant direct implants, same size and length, not one has failed as of yet. Nonetheless, there are so many uncoated implants that work so well I feel that coated implants should be reserved for areas of very poor bone quality or to replace failed implants.

The coated Implants are now completely different as the coating is rapidly resorbed and in fact rapidly excreted by the body as shown research by Wennerberg and Jimbo ( Pg 1163 Jomi April issue ) when labelled with Ca45. So our past issues are merely a distant bad dream. As I said the Thematic Review Pg 1154 Vol 26 No6 is real good read on this topic. Peter

Well thanks a lot everybody for enlightening me. one doubt for Dr Alejandro Berg...though the rate of migration of cells in compact bone is less as compared to trabecular bone, but cells do migrate and in these cases of slow migration of the blast cells wont having surface treatment or coating be an advantage. there might not be any advantage of coating as Dr Peter points out but surface treatments should definitely be advocated...atleast in the lower half of the implants(to prevent rough surface from being exposed to the oral cavity)

Dr. Fairbairn is entirely correct when he states that bioactive implant surfaces have a rapid resorption. The release of free ionic calcium from low crystallinity molecular impregnated surfaces has a direct effect on bone metabolism by upregulating osteoblast metabolism. No more issues with appositional HA plasma sprayed surfaces. With regard to bone density, there is a misconception when using bone density types. There is no ridge where the bone density is homogeneous throughout osteotomy depth. There are usually multiple bone densities as you drill apically. The object here is to drill atraumatically, place an implant with an architecture that minimizes compression microfracture, and then take advantage of an implant surface with ideal chemistry (release of Ca+ ions)to enhance bone metabolism. And, since some previous posters have accused me of a lack of humility, you can read my previous posts to read about what system I am referring to. RJM