Opening up previously extracted site, and appears to have some soft bone?

In this scenario, after extraction, socket preservation, come back 3-4 months for implant placement:

I will reflect the gingiva easily off the bone. However, I notice the first few mm of the crestal to be somewhat soft. If I were to currette it until it is solid bone, it would leave a defect.

Should I assume this somewhat soft area is consolidating bone (since it reflected easily, and appears to be part of the bone), and plan and place my implant accordingly? Or should I be either be, closing it back up and letting it heal vs curretting it out until it is completely hard bone?

I’m not talking about when it’s clear the bone graft didnt take and is just flaking off that needs to be removed, or if there is soft tissue ingrowth into the socket site.

Thank you!

Thanks for your question. I took the opportunity to use our new OsseoNews AI to research your question. Took awhile to get the right terms to pose to the AI, but eventually got some feedback (the literature calls “soft” bone, low density bone, so that was one of the issues trying to get a good response). The answers are below. Let me know if this helps. seems like osseodensification can help? References at the bottom.

To address the transformation of low bone density into high density bone, several studies highlight various methods and materials that can facilitate this process.

One study focused on the use of autologous conditioned serum (ACS) in conjunction with horizontal bone augmentation. The results indicated that the use of ACS significantly increased both the horizontal dimension of bone and the density of newly formed bone compared to control groups. This suggests that ACS can enhance bone regeneration and density in areas with initial low bone density.

Another research evaluated the effects of osseodensification techniques using Densah burs, which compact the bone and leave residual particles that act as an autograft. This method demonstrated a significant increase in primary stability and a decrease in crestal bone loss over time, indicating that osseodensification can effectively improve bone density around dental implants.

Additionally, a study on bone grafting techniques showed that calvarial split bone grafts maintained high bone density and volume over time, suggesting that specific grafting methods can also contribute to improved bone density.

In summary, techniques such as the application of autologous conditioned serum, osseodensification, and the use of specific bone graft materials can effectively convert low bone density into higher density bone, promoting better outcomes in dental implant procedures and bone regeneration.

On the subject of hard bone vs soft bone in general:

The context provides insights into the differences between soft and hard bone in relation to dental implants and their stability. Here’s a summary based on the provided studies:

  1. Implant Stability and Bone Density:

    • Implants in “hard” bone generally show higher primary stability compared to those in “soft” bone. This is due to the increased density and strength of hard bone, which provides better support for the implant.
    • In “soft” bone, undersized drilling protocols can improve primary stability, but the stability is still generally lower than in hard bone.
  2. Implant Design and Bone Type:

    • The design of the implant, such as the presence of apical screw threads, can influence stability. Implants with specific designs may perform better in soft bone by increasing the contact area and enhancing stability.
    • Longer implants tend to provide better stability in both types of bone, but the effect is more pronounced in soft bone.
  3. Stress Distribution:

    • Stress distribution around implants is influenced by bone density. In low-density (soft) bone, stress is higher, which can lead to bone fracturing under traumatic loading conditions.
    • The type of implant (e.g., screw-type vs. cylinder-type) and its length can affect stress distribution, with screw-type and longer implants generally performing better in soft bone.
  4. Insertion Torque:

    • Wide-pitch implants are more suitable for soft bone as they provide greater insertion torque, which is crucial for stability. Fine-pitch implants are better suited for hard bone.

Overall, the choice of implant design and surgical technique should consider the bone density to optimize implant stability and reduce the risk of complications.

REFERENCES

An extraction, with or without a graft, is going to heal from the apex of the cone coronally so what you describe is totally normal. Just drill into it and place your fixture… It could also be that you overfilled the site with graft material and that first couple of millimeters of soft bone was never supposed to be there in the first place. I believe that drilling your osteotomy will jump start the blood supply to the area and only help the remodeling process which is why I never wait more that 6-8 weeks after grafting an extraction to place a fixture. I expect to place the fixture into soft bone and I subscribe to the idea that the osteotomy into the soft bone is therapy in a sense and only facilitates better outcomes. Just my opinion/observation.

Pro tip : before open the gingiva you can always check bone density from cbct