Poly(3-hydroxybutyrate) (PHB) patches for covering anterior skull base defects – an animal study with minipigs

Abstract

The examinations revealed an increasing closure of bone defect corresponding with time. The anterior skull base bone defect was completely closed after 9 months. The histological findings revealed a connective tissue and callus formation around the PHB patches with fibroblasts and foreign body/giant cell reaction growing through PHB membrane pores. There were no reactions or adhesions between brain and PHB or dura mater and PHB, respectively. Investigations of biodegradation and electron microscopy revealed a continuous breakdown of PHB in the course of time with variations due to different PHB structures. Microbiological investigations could not detect any florid intracranial infection.

Radially Aligned, Electrospun Nanofibers as Dural Substitutes for Wound Closure and Tissue Regeneration Applications

“…In the present work, the biodegradable polymer PCL was chosen as a material for dural substitute because PCL has some advantages compared with other bioabsorbable polyesters. Heterogeneous degradation of PGA and poly( L -lactic acid) (PLLA) could lead to a sudden increase of degradation products, resulting in acidic conditions and toxic reactions in the surrounding tissue 3. The degradation of PCL is slower, produces less-acidic degradation products, and has been studied as a wound dressing material since the 1970s 38.…”

“…Dural substitutes are often needed after a neurosurgical procedure to expand or replace the resected dura mater 2. Although a lot of efforts have been made, the challenge to develop a suitable dural substitute has been met with limited success 3. Autografts (e.g., fascia lata, temporalis fascia, and pericranium) are preferred because they do not provoke severe inflammatory or immunologic reactions, but they are limited by potential drawbacks such as difficulty in achieving a watertight closure, formation of scar tissue, insufficiently accessible graft materials to close large dural defects, and additional incisions for harvesting the graft 4,5.…”

“…Natural absorbable polymers, including collagen, fibrin, and cellulose, present the potential risk of infection 11. As a result, synthetic polymers such as poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), poly(lactic acid) (PLA), polyglycolic acid (PGA), PLA-PCL-PGA ternary copolymers, and hydroxyethylmethacrylate hydrogels have recently attracted attention as biodegradable implant materials for dural repair 3,5,8–11. Because of their bioabsorbability, they are expected to cause only a small risk of infection with some minor long-term adverse effects.…”

Development of a glial cell-derived neurotrophic factor-releasing artificial dura for neural tissue engineering applications

“…This membrane can be damaged by trauma to the brain or spinal cord 3,4 . Many synthetic and natural materials are employed in neurosurgery to repair dural defects 2,[5][6][7][8][9][10][11][12][13][14][15][16] . However, autografts require an accessible site and an additional operation for obtaining a healthy region of the dura.…”

Biopolymers in Medical Implants

“…However, much of the research is focused on poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (P (3HB-co-3HHx)) and several blend composites of PHAs. Blends of PHB and PHBV with polyglactin (Gotfredsen et al 1994), bioactive glass (Zheng et al 2003), tricalcium phosphate (Zheng et al 2007;Liu and Wang 2007), wollastonite (Li and Chang 2004;Li et al 2008), natural coral (Al-Salihi and Samsudin 2004) and hydroxyapatite (HA) (Bernd et al 2009) are some of the reports for bone scaffold synthesis. Doyle et al (1991), experiments in rabbits using PHB based implants for bone tissue regeneration showed favourable results without any undesirable chronic inflammatory response after implantation periods up to 12 months (Doyle et al 1991;Luklinska and Bonfield 1997).…”