Bone and Tissue Engineering of The Temporomandibular Joint (condyle)

Abstract

Bone and tissue engineering of the temporomandibular joint condyle provides a less invasive repair or replacement option than the current gold standard of repair. To accomplish this, the anatomy and physiology of the rat and rabbit mandibular condyles were extensively studied using histology staining techniques and micro-CT analysis. The analysis revealed key anatomical and physiological variations between the osteochondral joints of rats and rabbits. Notably, the condyles of both species contained heparin, heparan sulphate, keratan sulphate and chondroitin sulphate. Polarised light microscopy (PSR) images showed the presence of collagen type III in the cartilage layers, with disproportionate distribution across the cartilage zones. Using this information, a layered construct was designed to mimic the anatomy of a representative portion of the mandibular cartilage and bone. The construct was assembled using bone marrow-derived human mesenchymal stem cells (bmHMSCs), electrospun polycaprolactone (PCL) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) fibers in both random and aligned arrangements, type I collagen hydrogel and freeze dried PHBV(3HV). Positive cell morphology and adhesion was detected within the construct layers over a 14-day period through florescent and histological staining methods. The bmHMSCs adhered well to the layers and followed the fibre direction, suggesting the potential for further development of this construct for in-vitro testing of TMJ condyle bone and tissue engineering applications. The use of electrospun PCL and PHBV fibers, combined with type I collagen hydrogel and freeze dried PHBV(3HV), enhanced the mechanical properties and biocompatibility of the layered construct. This approach ensured a high surface-to-volume ratio, and the inter-connecting pores facilitated cell adhesion and proliferation. Overall, this research provides a promising foundation for the development of bone and tissue engineered TMJ condyles, offering an alternative to current repair methods.

Date of Award	25 Oct 2024
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Julie Gough (Supervisor) & Sarah Cartmell (Supervisor)