NovoSorb 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
A temporary, non-biodegradable layer closes the wound, limiting moisture loss, while also serving as a barrier to outside bacteria2,3.
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.
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 infection – Unlike biologics, BTM’s synthetic composition is not a food supply for bacteria 4
- Designed to minimise scarring and contracture – BTM facilitates the human body to regenerate a neodermis2,5,6
- Cost effective alternative to biologics – typically less than biologic alternatives
- No cold storage – can be stored at room temperature (≤ 25° C)
- Large sizes – up to 20x40cm
- Easy application – cut 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
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.
Integration process of NovoSorb® BTM
Over a period of approximately 2 to 3 weeks, NovoSorb® BTM integrates into the wound bed through cellular infltration.
NovoSorb® BTM fully integrated
The dermis is regenerated within the matrix. Once fully integrated, the sealing membrane is ready for removal.
Sealing membrane removed
Once the sealing membrane is removed the neodermis is ready for secondary treatment.
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.
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.
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
Struts
The solid structural elements of the matrix
Scanning Electron Microscopic
Chamber
The chambers (or cells) highlighted are ~1mm in height
Pores
Smooth, round connections between two chambers. The pores vary in size and average ~188µm10
The BTM chambers compartmentalise 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
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 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.
Day 22
- extracellular matrix becomes more dense by 3 weeks.
Day 33
- Signifcant dermal integration is achieved.
Patient Histology7
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 at 8 months
Patient at 12 months
completely gone Fat cells (adipocytes)
Patient at 18 months
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 integrating, 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.