NovoSorb BTM

The Difference is BTM

NovoSorb® BTM (Biodegradable Temporising Matrix) is a synthetic, biodegradable and biocompatible device designed to facilitate the dermis to grow within a patented polyurethane matrix. When ready, the sealing membrane is removed, leaving a fully vascularised dermis, ready for definitive closure.

BTM is a bilayer matrix

Feature Product
Sealing membrane
Adhesive

A temporary non-biodegradable layer closes the wound, limiting moisture loss while also serving as a barrier to outside bacteria2,3.

NovoSorb matrix

A 2mm bioabsorbable open cell matrix allows for the infiltration of cellular materials and serves as a matrix to aid in the reconstruction of the deeper layers (dermis) of the skin4.

NovoSorb matrix

A 2mm bioabsorbable open cell matrix allows for the infiltration of cellular materials and serves as a matrix to aid in the reconstruction of the deeper layers (dermis) of the skin4.

The difference is BTM:

  • Robust in the presence of infectionUnlike biologics, BTM’s synthetic composition is not a food supply for bacteria
  • Designed to minimise scarring and contractureBTM facilitates the human body to regenerate a neodermis2,5,6
  • Cost effective alternative to biologicstypically less than biologic competitors
  • No cold storagecan be stored at room temperature (≤ 25° C)
  • Large sizesup to 20x40cm
  • Easy applicationcut and apply with sutures or staples

Indications

It is indicated for full or deep partial thickness burns, surgical and reconstructive wounds and traumatic wounds.

Phases of BTM Integration

Plus Minus
BTM Work
NovoSorb® BTM implanted into a surgically debrided wound bed

The wound is physiologically closed, limiting the risk of infection, evaporative moisture loss and contraction1,2.

BTM Work
Integration process of NovoSorb® BTM

Over a period of approximately 2 to 3 weeks, NovoSorb® BTM integrates into the wound bed through cellular infltration.

BTM Work
NovoSorb® BTM fully integrated

The dermis is regenerated within the matrix. Once fully integrated, the sealing membrane is ready for removal.

BTM Work
Sealing membrane removed

Once the sealing membrane is removed the neodermis is ready for secondary treatment.

BTM Work
Secondary treatment

Method of secondary treatment is left to the physician’s clinical choice (e.g. closure by SSG, or closure by secondary intent). The NovoSorb® BTM progressively biodegrades and is fully absorbed in approximately 18 months7.

Converting wound repair into regeneration

NovoSorb BTM compartmentalises a large wound into a series of interconnected microwounds. The body easily heals microwounds, promoting organised regenerative healing.
Regeneration
Normal Healing

The body’s natural reparative process follows the chaotic, unorganised laying down of fibrotic tissue in order to rapidly close the wound. This is followed by months of remodeling and scar contraction.

Regeneration
Regeneration
Healing with BTM

NovoSorb BTM provides a unique matrix for organised healing. Cells and blood vessels migrate into the BTM and a new vascularised dermal-like structure is formed5. The body heals each chamber as a discrete small wound8.

BTM Microarchitecture

BTM is an open cell, non-reticulated matrix with interconnected chambers comprised of an estimated 94.2% open space9. This microstructure is stabilised by struts and the chambers are linked by pores, allowing free flow of fluid.
A photomicrograph of NovoSorb
BTM Microwound
Struts
Struts

The solid structural elements of the matrix

Scanning Electron Microscopic
BTM Microwound
Chamber
Chamber

The chambers (or cells) highlighted are ~1mm in height

Pores
Pores

Smooth, round connections between two chambers. The pores vary in size and average ~188µm10

The BTM chambers compartmentalize the wound, creating microwounds that the body can heal through regeneration. The chambers create a physical barrier that aids in minimising the foreign body response and helps prevent encapsulation. As healing progresses, a neodermis develops through the matrix.

Cellular Infiltration and Integration through NovoSorb BTM11

Plus Minus

When applied, BTM is rapidly infiltrated with hemoserous fluid. As cellular migration begins, the chambers are infiltrated by a variety of cell types with the interconnecting pores7 allowing exchange of nutrients and waste. As healing progresses and a neodermis develops through the matrix, the struts hold their shape, maintaining the microstructure into the remodelling phase.

BTM Day
BTM Day 15
  • Cellular activity is seen throughout.
  • Light foreign body response is present without encapsulation.
  • Fibroblasts commence laying down extracellular matrix with low density after 2 weeks.
BTM Day
Day 22
  • extracellular matrix becomes more dense by 3 weeks.
BTM Day
Day 33
  • Signifcant dermal integration is achieved.

Patient Histology7

Plus Green

BTM is designed to facilitate growth, then safely disappear. BTM gradually hydrolyses, shrinking and dissipating until fully reabsorbed in approximately 18 months, leaving a healthy, vascularised neodermis7.

Patient at 7 months
Patient Month
Patient Month
Uniform growth of tissue throughout
Patient at 8 months
Patient Month
Patient Month
Macrophages have eaten through smooth wall of polymer Corners are sofening and rounding
Patient at 12 months
Patient Month
Patient Month
BTM FBR almost
completely gone
Fat cells (adipocytes)
Note dissipation of giant cells (lef arrow). Few remnants continue to degrade (right arrow).
Patient at 18 months
Patient Month
BTM is fully hydrolysed and a fully vascularised neo-dermis remains. Corresponding disappearance of macrophages.
Boxes represent BTM

References

  • Dearman BL, LiA, Greenwood JE. Optimization of a polyurethane dermal matrix and experience with a polymer-based cultured composite skin. J Burn Care Res. 2014; 35(5): 437-48.
  • Greenwood JE, Dearman BL. Comparison of a sealed, polymer foam biodegradable temporising matrix against Integra(R) dermal regeneration template in a porcine wound model. J Burn Care Res. 2012; 33:163-73.
  • Wagstaff MJD, Schmitt B, Caplash Y, Greenwood JE. Free flap donor site reconstruction: A prospective case series using an optimized polyurethane temporising matrix. Eplasty. 2015; 15:231-48.
  • Greenwood JE, Schmitt BJ, Wagstaff MJD. Experience with a synthetic bilayer Biodegradable Temporising Matrix in significant burn injury. Burns Open. 2018;2(1):17-34.
  • Greenwood JE, Dearman BL. Split skin graft application over an intergrating, biodegradable temporising polymer matrix: immediate and delayed. J Burn Care Res. 2012; 33:7-19.
  • Wagstaff MJD, Slana IM, Caplash Y, Greenwood JE. Biodegradable Temporising Matrix (BTM) for the reconstruction of defects following serial debridement for necrotising fasciitis: A case series. Burns Open. 2019; 3:12-30.
  • Wagstaff MJD, Schmitt BJ, Coghlan P, Finkemeyer JP, Caplash Y, Greenwood JE. A biodegradable polyurethane dermal matrix in reconstruction of free flap donor sites: a pilot study. ePlasty 2015; 15:102-18.
  • Greenwood JE, Wagstaff MJD (2016) The use of biodegradable polyurethane in the development of dermal scaffolds. In: Cooper SL, Guan J (eds) Advances in Polyurethane Materials. 1st edn. Woodhead Publishing, pp 631-62.
  • Data on file TD-114.
  • Internal testing.
  • Data on file: Punch biopsies.
  • Brown CN and Finch JG. Which mesh for hernia repair? Ann R Coll Surg Engl 2010; 92(4): 272-278.