Temporomandibular Joint Disc Replacement Research Articles

Assessment of Long-Term Effects and Patient Satisfaction following TMJ Disc Replacement Surgery

ABSTRACT Objectives: The purpose of this research is to evaluate patient satisfaction and long-term consequences after temporomandibular joint (TMJ) disc replacement surgery in a tertiary care environment. Methods: 500 patients who had TMJ disc replacement surgery at a tertiary care facility between 2010 and 2015 were the subject of a retrospective investigation. Pre-operative clinical features, demographic information, and intraoperative information were gathered. Standardized measurements were used to evaluate functional results, pain levels, and patient-reported outcomes. Descriptive statistics, paired t-tests, and significance set at P < 0.05 were all used in the statistical analysis. Results: There were notable improvements in functional outcomes, with a mean increase in lateral excursion from 8.7 mm to 12.6 mm (P < 0.001) and maximal incisal opening from 30.5 mm to 40.2 mm (P < 0.001). The pain level was found to have greatly diminished, as evidenced by the VAS scores falling from 7.8 to 3.2 (P < 0.001). The Jaw Function Limitation Scale scores (42.6 to 21.8, P < 0.001) and patient-reported outcome measures scores (58.3 to 76.5, P < 0.001) exhibited significant increases in patient-reported outcomes. Conclusion: In conclusion, tertiary care TMJ disc replacement surgery shows positive long-term outcomes, such as enhanced jaw function, less discomfort, and high patient satisfaction. This research supports the ongoing use of TMJ disc replacement surgery as a potential therapy for refractory TMJ disease, although noting its limitations.

Biomimetic construction of a lubricious hydrogel with robust mechanics via polymer chains interpenetration and entanglement for TMJ disc replacement

Developing a temporomandibular joint (TMJ) disc substitute with reliable long-term functional support has faced a huge challenge in replicating the unique microarchitecture, biomechanics and lubrication of the natural tissue. Herein, a novel biomimetic hydrogel consisting of graphene oxide nanosheets modified anionic polyurethane (nGO-APU) and polyvinyl alcohol (PVA) was successfully fabricated through combined freeze-thawing and annealing treatment. Of which, the annealed PVA (a-PVA) with entanglement network acted as the main frame to provide mechanical support, while the interpenetrated nGO-APU chains endowed the function for water retention and lubrication, thus resisting the compressive loads and fulfilling a durable energy absorbing and cushion. The resultant nGO-APU/a-PVA hydrogel achieved better lubrication effect through the synergistic effect of fluid film and boundary lubrication, exhibiting a low friction coefficient of about 0.06, close to the natural TMJ disc. After implantation into rabbit TMJ for up to 24 weeks, the nGO-APU/a-PVA hydrogel kept the structural stability to offer effective protection against wearing of the cartilage, meanwhile ameliorating the worsening of osteoarthritis. The finite element analysis (FEA) further proved that the resultant hydrogel could effectively disperse the applied stress and dissipate energy under practical loading conditions. This strategy based on a biomimetic hydrogel with enhanced mechanical stability and lubrication performance shows clinical promise for TMJ disc replacement.

A mechanical evaluation of polyvinyl alcohol hydrogels for temporomandibular joint disc replacement

The temporomandibular joint (TMJ) is a bilateral ginglymoarthroidal joint containing a fibrocartilaginous disc which distributes compressive stress and reduces friction on the articulating surfaces of the joint. Initially, conservative treatments can address disorders of the TMJ, but surgical procedures such as discectomy may be employed if dysfunction persists. Unfortunately, discectomy increases friction and alters the mechanical behavior of the TMJ when the disc is not replaced. An ideal replacement for the TMJ disc would restore healthy function of the joint and prevent further degeneration. Rigorous evaluation of materials is necessary to ensure the safety and efficacy of novel implants. Poly(vinyl) alcohol (PVA) hydrogels have been suggested as a good candidate for artificial cartilage replacement in other applications and are promising for replacing the TMJ disc due to their biocompatibility, low friction, and biomimetic levels of hydration. The objective of this study was to mechanically characterize hydrogel formulations of 15, 20, and 25% PVA and to compare them with the ovine TMJ disc to investigate the appropriateness of PVA hydrogels for TMJ disc replacement in a translational model. Experimental evaluations were conducted in indentation, unconfined compression, friction, and uniaxial tension. There were no statistically significant differences in the coefficient of friction between the PVA hydrogels and ovine TMJ disc. No statistically significant differences were found between at least one PVA hydrogel group and the TMJ disc for the indentation properties or the unconfined compression properties at low stretch magnitudes. The 20% PVA and 25% PVA hydrogels exhibited significantly higher failure stretch as compared to the ovine TMJ disc, and they were not statistically different in ultimate tensile strength from the TMJ disc in the mediolateral direction. However, the ovine TMJ disc tensile elastic moduli were 630 times larger in the anteroposterior direction and 53 times larger in the mediolateral direction than the stiffest PVA hydrogel. Ultimately, the 25% PVA hydrogel was the best candidate for TMJ disc replacement, demonstrating the most similarity to the ovine TMJ disc compressive properties; however, tensile reinforcement of the hydrogels would be necessary to approach the tensile modulus of the native TMJ disc.

Mechanical characterization and viscoelastic model of the ovine temporomandibular joint Disc in indentation, uniaxial tension, and biaxial tension

There have been recent investigations into developing disc replacements and regenerative medicine to treat internal derangements of the temporomandibular joint (TMJ) disc. Previous attempts at disc replacements have faced challenges related in part to a limited understanding of the TMJ's complex mechanical environment. The purpose of this study was to characterize the mechanical behavior of the ovine TMJ disc and to derive viscoelastic constitutive models from the experimental data. Fresh ovine TMJ discs were tested in indentation stress-relaxation tests on the inferior surface, uniaxial tension tests to failure, and dynamic biaxial tensile tests. Results showed an order of magnitude stiffer behavior in tension in the anteroposterior (primary fiber) direction compared to the mediolateral direction. The stiffness in tension was much greater than in compression. Regional comparisons showed greater elastic moduli in indentation in the posterior and anterior bands compared to the central region. A hyper-viscoelastic constitutive model captured the dynamic stress-stretch behavior in both indentation and biaxial tension with good agreement. These data will support ongoing and future computational modeling of local TMJ mechanics, aid in biomaterials identification, and ultimately enhance development of implant designs for TMJ disc replacement.

Autologous adipose stem cells and polylactide discs in the replacement of the rabbit temporomandibular joint disc

The temporomandibular joint (TMJ) disc lacks functional replacement after discectomy. We investigated tissue-engineered bilayer polylactide (PLA) discs and autologous adipose stem cells (ASCs) as a potential replacement for the TMJ disc. These ASC discs were pre-cultured either in control or in differentiation medium, including transforming growth factor (TGF)-β1 for one week. Prior to implantation, expression of fibrocartilaginous genes was measured by qRT-PCR. The control and differentiated ASC discs were implanted, respectively, in the right and left TMJs of rabbits for six (n = 5) and 12 months (n = 5). Thereafter, the excised TMJ areas were examined with cone beam computed tomography (CBCT) and histology. No signs of infection, inflammation or foreign body reactions were detected at histology, whereas chronic arthrosis and considerable condylar hypertrophy were observed in all operated joints at CBCT. The left condyle treated with the differentiated ASC discs appeared consistently smoother and more sclerotic than the right condyle. The ASC disc replacement resulted in dislocation and morphological changes in the rabbit TMJ. The ASC discs pre-treated with TGF-β1 enhanced the condylar integrity. While adverse tissue reactions were not shown, the authors suggest that with improved attachment and design, the PLA disc and biomaterial itself would hold potential for TMJ disc replacement.

Use of adipose stem cells and polylactide discs for tissue engineering of the temporomandibular joint disc

There is currently no suitable replacement for damaged temporomandibular joint (TMJ) discs after discectomy. In the present study, we fabricated bilayer biodegradable polylactide (PLA) discs comprising a non-woven mat of poly(L/D)lactide (P(L/D)LA) 96/4 and a P(L/DL)LA 70/30 membrane plate. The PLA disc was examined in combination with adipose stem cells (ASCs) for tissue engineering of the fibrocartilaginous TMJ disc in vitro. ASCs were cultured in parallel in control and chondrogenic medium for a maximum of six weeks. Relative expression of the genes, aggrecan, type I collagen and type II collagen present in the TMJ disc extracellular matrix increased in the ASC-seeded PLA discs in the chondrogenic medium. The hypertrophic marker, type X collagen, was moderately induced. Alcian blue staining showed accumulation of sulphated glycosaminoglycans. ASC differentiation in the PLA discs was close to that observed in pellet cultures. Comparison of the mRNA levels revealed that the degree of ASC differentiation was lower than that in TMJ disc-derived cells and tissue. The pellet format supported the phenotype of the TMJ disc-derived cells under chondrogenic conditions and also enhanced their hyalinization potential, which is considered part of the TMJ disc degeneration process. Accordingly, the combination of ASCs and PLA discs has potential for the development of a tissue-engineered TMJ disc replacement.

Electrosonographic characteristics of sounds from temporomandibular joint disc replacement

The purpose of this study was to investigate the waveform and electrosonographic characteristics of sounds emanating from internal derangement of the temporomandibular joint (TMJ). TMJ sounds were recorded from 10 joints of normal people (NP), 10 joints from patients with anterior disc displacement with reduction (DDR) and 20 joints from patients with anterior disc displacement without reduction (DDNR). The sounds were analysed through fast Fourier transfer methods to observe their waveforms and electrosonographic characteristics. The observations were then used in differentially diagnosing internal derangement. Wave pattern and electrosonography (ESG) differed among the NP, DDR and DDNR groups. There was very little difference in frequency between the sounds from DDR and DDNR, but the amplitude of the DDR sounds was higher than those of DDNR and NP. The sensitivity and specificity of ESG diagnosis for DDR were 77.2% and 93.3%, respectively, while for DDNR they were 81.6% and 64.7%, respectively.

Clinically Relevant Cell Sources for TMJ Disc Engineering

Tissue-engineering of the temporomandibular joint (TMJ) disc aims to provide patients with TMJ disorders an option to replace diseased tissue with autologous, functional tissue. This study examined clinically relevant cell sources by comparing costal chondrocytes, dermal fibroblasts, a mixture of the two, and TMJ disc cells in a scaffoldless tissue-engineering approach. It was hypothesized that all constructs would produce matrix relevant to the TMJ disc, but the mixture constructs were expected to appear most like the TMJ disc constructs. Costal chondrocyte and mixture constructs were morphologically and biochemically superior to the TMJ disc and dermal fibroblast constructs, and their compressive properties were not significantly different. Costal chondrocyte constructs produced almost 40 times more collagen and 800 times more glycosaminoglycans than did TMJ constructs. This study demonstrates the ability of costal chondrocytes to produce extracellular matrix that may function in a TMJ disc replacement.

Electrosonographic characteristics of sounds from temporomandibular joint disc replacement

The purpose of this study was to investigate the waveform and electrosonographic characteristics of sounds emanating from internal derangement of the temporomandibular joint (TMJ). TMJ sounds were recorded from 10 joints of normal people (NP), 10 joints from patients with anterior disc displacement with reduction (DDR) and 20 joints from patients with anterior disc displacement without reduction (DDNR). The sounds were analyzed through fast Fourier transfer methods to observe their waveforms and electrosonographic characteristics. The observations were then used in differentially diagnosing internal derangement. Wave pattern and electrosonography (ESG) differed among the NP, DDR and DDNR groups. There was very little difference in frequency between the sounds from DDR and DDNR, but the amplitude of the DDR sounds was higher than those of DDNR and NP. The sensitivity and specificity of ESG diagnosis for DDR were 77.2% and 93.3%, respectively, while for DDNR they were 81.6% and 64.7%, respectively.

Histologic and histochemical changes in failed auricular cartilage grafts used for a temporomandibular joint disc replacement: A report of three cases and review of the literature

Histologic and histochemical changes in failed auricular cartilage grafts used for a temporomandibular joint disc replacement: A report of three cases and review of the literature

Discussion: Temporomandibular Joint Disc Replacement Made by Tissue-Engineered Growth of Cartilage

Discussion: Temporomandibular Joint Disc Replacement Made by Tissue-Engineered Growth of Cartilage

Temporomandibular joint disc replacement made by tissue-engineered growth of cartilage

Objective : To test the effectiveness of the new technique of tissue-engineered growth of cartilage, temporomandibular joint (TMJ) disc replacements were created by seeding dissociated chondrocytes on synthetic, three-dimensional, bioresorbable polymer constructs of a predetermined anatomic shape, incubating the cell-polymer constructs in vitro, and transplanting them into test animals. Materials and Methods : Twelve highly porous and bioresorbable cell-transplantation devices in the shape of TMJ discs were created using biodegradable polylactid and polyglycolic acid fibers. Bovine articular cartilage was dissociated into chondrocytes and the cells were allowed to attach to the three-dimensional polymer scaffolds and multiply in vitro. After 1 week, the cell-polymer constructs were implanted subcutaneously into nude mice. The neocartilage was assessed by magnetic resonance imaging (MRI) techniques, gross inspection, histology, and biomechanical and biochemical analysis after 12 weeks. Results : All implants seeded with chondrocytes showed gross evidence of histologically organized hyaline cartilage. The scaffolds maintained their specific shape. They not only showed appropriate intrinsic stability during neomorphogenesis of cartilage in vitro and in vivo, but also seemed to guide the growth of cartilage. The presence of sulfated glycosaminoglycans was shown by aldehyde fuchsin alcian blue staining of the specimens. Type II collagen, considered to be indicative of cartilage formation, was found in the specimens tested. MRI showed signal characteristics similar to those of hyaline cartilage. Analysis of neocartilage force/displacement curves and aqueous phase compliance using a closed compression chamber suggested that the ability of the constructs to resist deformation was similar to that of native donor cartilage. Conclusion : The technology of tissue-engineered growth of cartilage on individually designed scaffolds may have many applications not only in reconstructive surgery of the TMJ, but also in craniomaxillofacial, plastic, and orthopedic surgery.

A two-stage procedure for temporomandibular joint disc replacement using free pericranial grafts: A preliminary report

A preliminary study of the use of free pericranial grafts as an alternative to other autogenous or alloplastic materials for temporomandibular joint disc replacement is presented. Postoperative results show improved function and alleviation of other symptoms.

The use of autologous auricular cartilage for temporomandibular joint disc replacement: A preliminary report

The technique of harvesting auricular cartilage and its use in 22 patients (35 joints) is described. Follow-up was from 3 to 24 months. Pain relief was achieved in 90% of the cases. Function was equal or better to the preoperative situation in all cases.

Rapid condylar degeneration after glenoid fossa prosthesis insertion: Report of three cases

Three cases of temporomandibular joint disc replacement with a polymer glenoid fossa prosthesis, followed by rapid condylar degeneration, are reported. The relationship between this degeneration and a consistent foreign body reaction to fragments caused by implant wear is postulated.

Comparative study of alloplastic materials for temporomandibular joint disc replacement in rabbits

Young adult, white New Zealand rabbits underwent either sham surgical procedures or discectomy. In the animals that underwent discectomy, either reinforced silicone or polytetrafluoroethylene-aluminum oxide (PTFE-Al2O3) implants were placed in the glenoid fossa. During gross sectioning, the silicone implants could be easily displaced from the specimen, while the PTFE-Al2O3 implants were firmly anchored. Histologically, fragmentation of the implants was seen in the silicone group; 21.4% of the implants placed were torn. Foreign body giant cell reactions reached a peak after eight weeks. Associated fibrosis and foreign body giant cell reactions were seen, resulting in a thickened capsule and resorption of the condyle and articular fossa. In the PTFE-Al2O3 group there was marked osteoclastic activity, with resorption and severe degenerative changes in both the condyle and glenoid fossa. The foreign body giant cell reaction was severe at all time intervals and increased with time. Tearing of the implant was observed in 46.2% of the joints. These results indicate a need for further evaluation of these materials as disc replacements in humans.