A randomized controlled preclinical trial on 3 interposal temporomandibular joint disc implants: TEMPOJIMS-Phase 2

Different methods of synthesizing poly(glycerol sebacate) (PGS): A review

Poly(glycerol sebacate) (PGS) is a biodegradable elastomer that has attracted increasing attention as a potential material for applications in biological tissue engineering. The conventional method of synthesis, first described in 2002, is based on the polycondensation of glycerol and sebacic acid, but it is a time-consuming and energy-intensive process. In recent years, new approaches for producing PGS, PGS blends, and PGS copolymers have been reported to not only reduce the time and energy required to obtain the final material but also to adjust the properties and processability of the PGS-based materials based on the desired applications. This review compiles more than 20 years of PGS synthesis reports, reported inconsistencies, and proposed alternatives to more rapidly produce PGS polymer structures or PGS derivatives with tailor-made properties. Synthesis conditions such as temperature, reaction time, reagent ratio, atmosphere, catalysts, microwave-assisted synthesis, and PGS modifications (urethane and acrylate groups, blends, and copolymers) were revisited to present and discuss the diverse alternatives to produce and adapt PGS.

Decellularized small intestine submucosa device for temporomandibular joint meniscus repair: Acute timepoint safety study

Temporomandibular joint (TMJ) Meniscus removal is an option for the patient to regain full range of motion if the disc is irreversibly damaged or unable to be reduced. However, this procedure leaves the joint vulnerable to condylar remodeling and degeneration. We have shown that extracellular matrix (ECM) scaffolds remodel into a tissue with near native TMJ meniscus in previous studies. The next step towards clinical translation is to manufacture the ECM scaffold as a device under good manufacturing practices (GMP) and test it in a pre-clinical animal study under good laboratory practices (GLP). The primary objective of this study was to evaluate the in-vivo histopathological response to a Prototype GMP manufactured device made of decellularized porcine small intestinal submucosa (SIS), by observing for signs of surrounding tissue reaction to the device that are indicative of an adverse host response in comparison to an empty control at 21 days post-surgical implantation in a canine TMJ meniscus removal and implant model in a GLP setting. The conclusive findings were that the ECM device is safe for placement in the TMJ. After 21 days post implantation, histology of tissue surrounding the device and draining lymph nodes showed that the Prototype GMP device had no negative effects compared to the empty site (as evaluated by the board-certified veterinary pathologist). Furthermore, there was a lack of negative findings for clinical pathology (hematology and clinical chemistry), mortality, and body weight/weight change. Future studies will go to one year after implantation to show that the remodel device remains as a viable tissue with near native mechanical properties.

Advances in Tissue Engineering of the Temporomandibular Joint Disc: An Overview of Current Status and Future Directions

Advances in tissue engineering have progressed to potentially offer a solution to temporomandibular joint disc (TMJ) disorders not amenable to conservative therapies. Conclusive treatment options for patients with end-stage disc disorders requires discectomy and reconstruction of the articular disc with various materials. Tissue engineering TMJ disc is a promising alternative to the limited and sometimes inadequate clinical options in the management of such disorders. However, tissue engineering is far from completion for the TMJ disc regeneration. This review briefly discusses the properties of native disc, the mechanism by which TMJ disorders manifest, and how a tissue engineered disc could assuage the problems inherent in the management of such disorders. Furthermore, the review addresses and provides updates to relevant themes of tissue engineering in regards to the TMJ disc, namely, the scaffolds, cells and biomarkers, hurdles in tissue engineering of the disc, and its application in translation to the clinical practice and future directions.

Additive Manufactured Poly(ε-caprolactone)-graphene Scaffolds: Lamellar Crystal Orientation, Mechanical Properties and Biological Performance

Understanding the mechano-biological coupling mechanisms of biomaterials for tissue engineering is of major importance to assure proper scaffold performance in situ. Therefore, it is of paramount importance to establish correlations between biomaterials, their processing conditions, and their mechanical behaviour, as well as their biological performance. With this work, it was possible to infer a correlation between the addition of graphene nanoparticles (GPN) in a concentration of 0.25, 0.5, and 0.75% (w/w) (GPN0.25, GPN0.5, and GPN0.75, respectively) in three-dimensional poly(ε-caprolactone) (PCL)-based scaffolds, the extrusion-based processing parameters, and the lamellar crystal orientation through small-angle X-ray scattering experiments of extruded samples of PCL and PCL/GPN. Results revealed a significant impact on the scaffold's mechanical properties to a maximum of 0.5% of GPN content, with a significant improvement in the compressive modulus of 59 MPa to 93 MPa. In vitro cell culture experiments showed the scaffold's ability to support the adhesion and proliferation of L929 fibroblasts (fold increase of 28, 22, 23, and 13 at day 13 (in relation to day 1) for PCL, GPN0.25, GPN0.5, and GPN0.75, respectively) and bone marrow mesenchymal stem/stromal cells (seven-fold increase for all sample groups at day 21 in relation to day 1). Moreover, the cells maintained high viability, regular morphology, and migration capacity in all the different experimental groups, assuring the potential of PCL/GPN scaffolds for tissue engineering (TE) applications.