February 10, 2021

And you thought EthOss was just for implants…

In this guest blog, Dr Renukanth Raman, Malaysia, discusses how modern graft materials have allowed us to revisit existing treatment protocols and consider new techniques to regenerate lost bone and retain more of the patients’ own teeth.

Periodontal intrabony defects are defined as those that occur within the bone and are generally surrounded by one to three bony walls or sometimes a combination (see Fig 1). This is caused by periodontal disease and usually occurs when there are different rates of disease progression on adjacent root surfaces.

Fig 1 (Papapanou & Tonetti, 2000)

These defects often appear as angular bone patterns between the teeth which can be associated with deep pocket depths, as illustrated below with Fig 2. However not all require surgical intervention. As with all periodontal cases, we start with an initial cause-related therapy and if this is well-executed, the majority of these pockets can be resolved, including those associated with intrabony defects. But we also frequently see cases where we are left with intrabony defects where the pockets do not resolve – these will require surgical intervention.

Fig 2 – Panoramic radiograph showing bone defect

The following case shows a patient that was treated for Generalised Periodontitis Stage 4 Grade C. She successfully underwent non-surgical debridement but was left with a residual deep pocket associated with a deep intrabony defect as shown on the radiograph below, which justified surgical intervention for this site.

It was important to consider what kind of surgery would successfully treat this case.  If we were just looking at healing to repair, we could use an access flaps and resective procedures. This would suffice but unfortunately is not the most ideal solution as it would likely leave significant additional attachment loss, as well as soft tissue recession.

Instead, we can look at regeneration. Regeneration is all about trying to predictably restore what has been lost due to disease.  We’re attempting to restore new ligaments, new cementum and new bone which is by no means an easy task.

Fig 3 – Radiograph shows deep intrabony defect

Regenerative Periodontal Therapy

This entire surgical procedure is based on the premise that if we can prevent epithelium and connective tissue ingrowth whilst maintaining the defect space, we are allowing the host to regenerate bone and ligaments.

How do we achieve this?

We achieve successful regenerative periodontal therapy by using biomaterials.

There are numerous options available including:

  • Cell occlusive membranes (resorbable membranes such as collagen or non-resorbable synthetic membranes)
  • Particulate grafts including autogenous bone, xenografts, allografts and synthetics
  • These materials can be used on their own or in combination and research suggests these materials actually works better when combined
  • Biologically active agents
  • Autologous blood constituent eg. PRP, CGF

We always want the best outcome for our patients so how do we chose what best suits the defect when there are so many options available to us? This can be problematic, especially if the clinician has no particular preference. When there are religious or ethical concerns at play, this decision can be much easier and whittled down to synthetic materials (no human or animal matter) or perhaps autogenous bone grafts (made from the patient’s own bone).

A closer look at secondary research

Data can give you definitive proof of regeneration, for example, research often suggests the “gold standard” autogenous bone as being highly effective in treating defects due to its osteoinductive potential.

Alloplastic bone grafts were shown to be less effective and were resorbing too fast, but most of these studies were carried out over 20 years ago. Synthetics have come a long way since then and are significantly more effective today with extremely high regenerative potential.  There is a large body of evidence showing the B-tricalcium phosphate (B-TCP) in particular is both osteoconductive with high osteoinductive potential, as well as resorbing at an appropriate rate for replacement by new bone formation.

EthOss uses a combination of Calcium Sulphate (35%) and B-TCP (65%), giving the bone graft some attractive properties:

Calcium Sulphate

  • Facilitates cell attachment and fibroblast migration over wound margins
  • Anti-bacterial
  • Time-limited osteoconductive (quick resorption timeframe)
  • Acts as a cell occlusive binder – ‘Pseudomembrane’ – meaning you do not need to use a separate collagen membrane

B-tricalcium phosphate

  • Highly osteoconductive
  • High osteoinductive potential
  • 100% resorbed and replaced by the host bone

I personally decided to try using EthOss for treating intrabony defects after getting outstanding results when I initially used it 3 years prior for implant placement and sinus augmentations.  Not needing to use a separate collagen membrane is particularly appealing.

Two wall periodontal bone defect case

The following is a case I had where non-surgical treatment had worked to reduce the inflammation but at this site the deep 2 walled intrabony defect prevented the re-establishment of a normal sulcus.

Quick tip– control the bleeding and any flap manipulation or changes to the flap design must be done before placing the material – this ensures the bleeding doesn’t saturate the graft when you’re trying to dry it.

Bleeding controlled

I prepared the EthOss and moulded the graft into the site – EthOss is particularly good for this. Once I was happy with the shape, I dried it out for around 5-6 minutes with a sterile gauze which sets the graft well.

Once the EthOss has set you can suture.  After one week there’s good soft tissue with little to no incision lines visible of hardly any inflammation (see image below, right)

One week post-op

At 1-year post-op, you can see excellent soft tissue healing (images below). The residual pocket is now 3mm (reduced from 8mm).

View the full case study here.

My final thoughts on using EthOss…

EthOss is a predictable material for Periodontal regeneration and I’ve been seeing consistent and reproducible results for my patients.

As EthOss does not require a separate collagen membrane it means I have reduced surgical time and less invasive flap designs are possible.  The Calcium Sulphate content within the material seems to contribute to extremely good soft tissue healing. Being 100% synthetic there are no ethical or religious concerns for my patients which is an incredibly important factor and of course, there are no immunological risks.

However, there are still some unanswered questions which I look forward to exploring as I gain more experience and see longer-term results:

Will the regenerated tissue last?
Long term follow up studies that show the tissue does last and the bone is maintained well in augmentation cases in implants but will the same be true for natural teeth?  As the material is completely resorbed and replaced by host bone my instinct is that the long-term results will be very predictable.  At present my longest-term follow-up is 2 years post-op which does illustrate very promising results, but it will be interesting to discover how this fares after 5 -10 years.

Overall, I will continue to use EthOss – it’s a pioneering product that celebrates true bone regeneration and allows me to offer more ethical procedures to my patients.

EthOss is definitely not just for implants… I am excited to continue exploring this material within the realms of natural teeth and periodontal treatments at my practice for many years to come.