Best Bone Grafting Material for Ridge Preservation After Extraction

Eric Rindler, DDS, MBA maintains a private practice limited to periodontics and dental implants in San Antonio, Texas. He has held an clinical assistant professor of general dentistry position at the University of Texas Health Science Center at San Antonio, and has served as a guest instructor at the Kois Center in Seattle, Washington.

Roberto J. Deloso, DDS maintains a private oral and maxillofacial surgery practice in Antioch, California. He is also a co-director and coordinator of the Delta Study Club, and a member of numerous dental associations, including the California Association of Oral & Maxillofacial Surgeons, American Association of Oral & Maxillofacial Surgeons, and International College of Oral & Maxillofacial Surgeons.

Inside Dentistry (ID): What is the best bone grafting material for ridge preservation following an extraction?

Dr. Michael A. Pikos: I have used mineralized allografts for extraction site management in my practice for more than 20 years. For the first 10 years, I used mineralized cancellous bone only (2-mm particle size) with very consistent and predictable results as evidenced clinically and with core biopsy histology. Upon re-entry at 4 months, I routinely found type 2 quality bone.

Over the past 10 years, I transitioned to using a gradient of cortical and cancellous mineralized bone (0.6 mm to 1.2 mm) again with very predictable outcomes (98%). However, upon re-entry of these grafted sites, I would routinely find an even denser bone quality than with cancellous only. Histology from these cores has also consistently shown a more mineralized matrix of bone.

In non-esthetic zone extraction site cases, I use a flapless approach and wait 4 months for re-entry in grafted 5-wall defects, including facial plate compromise up to 3 mm to 4 mm. I also use a d-PTFE membrane (10 years) tucked into a buccal and lingual subperiosteal pouch, which is removed at 4 weeks. For sites with greater buccal plate compromise, including complete plate loss, I add rhPDGF to the graft complex and use titanium-reinforced d-PTFE membrane with fixation.

In extreme cases (facial and lingual plate compromise), I use an open-flap approach with titanium-reinforced PTFE membrane with fixation, along with rhBMP-2 plus mineralized allograft and re-enter at 6+ months.

In esthetic zone extraction site cases, I especially use a flapless protocol for extraction site management (in non-immediate implant placement cases) that also includes the use of mineralized cortical cancellous bone (0.6 mm to 1.2 mm) for 4- and 5-wall defects with re-entry at 4 months. Here I typically use autogenous soft tissue (CTG, FGG) as a barrier and to increase soft-tissue volume. In compromised sites with complete facial plate loss I add rhPDGF and wait 5 months for re-entry. Finally, in extreme esthetic zone cases (facial and palatal plate loss) I add rhBMP-2 and re-enter at 6+ months.

To summarize, it is my opinion that this cortical cancellous gradient of 0.6 mm to 1.2 mm particle size seems to be the ideal allograft material and particle size for predictable and optimal graft incorporation for extraction site management cases. I was never able to obtain predictable graft results with either demineralized bone only or with xenografts.

Dr. Eric Rindler: The quick answer is a FDBA allograft of cancellous bone with particle sizes of 250 microns to 1000 microns, such as Puros® (Zimmer Dental, www.zimmerdental.com) or OraGRAFT® (LifeNet Health, www.lifenethealth.org). My “routine” ridge preservation also includes a barrier membrane. I am just as concerned with blocking the soft-tissue downgrowth (remember it is a race between fibroblast and osteoblast). I consider ridge preservation very important, however I want to stress that not every extracted tooth needs ridge preservation.

Ridge preservation is not simply placing bone in the hole—rather it is important to consider what you are trying to accomplish and how each specific case presents. Some questions to consider: Do you need to preserve ridge height or preserve ridge thickness or both? Is it that you really need to augment buccally (which is much different then ridge preservation)? Are you working in the esthetic zone? Is there any residual infection or soft tissue in the extraction socket? Are the bony walls intact? What is the timeline for treatment? Ridge preservation generally delays the implant placement by approximately 2 months when compared to an extraction without bone grafting.

There are times when ridge preservation can be a negative. If you have a molar with a thick buccal plate and well preserved interseptal bone, and you are choosing not to place an immediate implant, you might not need or want ridge preservation. This will likely lead to an implant that will lack interarch restorative space. Additionally, it will delay the implant placement. In an extraction where no bone grafting is placed I routinely place the implant at 8 weeks. When ridge preservation is completed, then implant placement is delayed until at least 16 weeks. I am a fan of bone grafting/ridge preservations when appropriate.

Dr. Roberto J. Deloso: For almost 20 years now, I have been using the same technique—using a 50/50 mix of freeze dried mineralized cortical bone (FDBA 300 microns to 500 microns) and OsteoGraf N-300 (250 microns to 420 microns) (Dentsply Implants, www.dentsplyimplants.com) overlayed by an impervious high-density PTFE membrane (Cytoplast GBR-200, Osteogenics, www.osteogenics.com), which is tucked under the buccal and lingual gingiva. With limited flap reflection and about 2 mm to 3 mm of exposed membrane, this has been able to maintain more ridge width than any other material or technique I have tried. Extensive curettage of the extraction socket to bleeding bone is better and if the bone is dense, I have even used a small fissure bur to perforate the walls to promote bleeding.

Of course the final result really counts on how much buccal/labial plate is left after extraction. Vertical root fracture cases will always present with buccal/labial bone loss. In cases where there is bony labial dehiscence, I have overfilled the area labially, and have had good results also. The only disadvantage of this technique is that I have to wait 6 months for implant placement.