There is a paucity of in vivo studies that investigate the safety and efficacy of temporomandibular joint (TMJ) tissue regeneration approaches, in part due to the lack of established animal models. Review of disease models for study of TMJ is presented herein with an attempt to identify relevant preclinical animal models for TMJ tissue engineering, with emphasis on the disc and condyle. Although degenerative joint disease models have been mainly performed on mice, rats, and rabbits, preclinical regeneration approaches must employ larger animal species. There remains controversy regarding the preferred choice of larger animal models between the farm pig, minipig, goat, sheep, and dog. The advantages of the pig and minipig include their well characterized anatomy, physiology, and tissue properties. The advantages of the sheep and goat are their easier surgical access, low cost per animal, and its high tissue availability. The advantage of the dog is that the joint space is confined, so migration of interpositional devices should be less likely. However, each species has limitations as well. For example, the farm pig has continuous growth until about 18 months of age, and difficult surgical access due to the zygomatic arch covering the lateral aspect of joint. The minipig is not widely available and somewhat costly. The sheep and the goat are herbivores, and their TMJs mainly function in translation. The dog is a carnivore, and the TMJ is a hinge joint that can only rotate. Although no species provides the gold standard for all preclinical TMJ tissue engineering approaches, the goat and sheep have emerged as the leading options, with the minipig as the choice when cost is less of a limitation; and with the dog and farm pig serving as acceptable alternatives. Finally, naturally occurring TMJ disorders in domestic species may be harnessed on a preclinical trial basis as a clinically relevant platform for translation.
The temporomandibular joint (TMJ) is an important structure for the masticatory system and the pathologies associated with it affect a large part of the population and impair people’s lifestyle. It comprises an articular disc, that presents low regeneration capacities and the existing clinical options for repairing it are not effective. This way, it is imperative to achieve a permanent solution to guarantee a good quality of life for people who suffer from these pathologies. Complete knowledge of the unique characteristics of the disc will make it easier to achieve a successful tissue engineering (TE) construct. Thus, the search for an effective, safe and lasting solution has already started, including materials that replace the disc, is currently growing. The search for a solution based on TE approaches, which involve regenerating the disc. The present work revises the TMJ disc characteristics and its associated diseases. The different materials used for a total disc replacement are presented, highlighting the TE area. A special focus on future trends in the field and part of the solution for the TMJ problems described in this review will involve the development of a promising engineered disc approach through the use of decellularized extracellular matrices.
Rehabilitation of atrophic jaws with conventional endosseous implant-supported overdentures and immediate loading protocols still presents a challenge nowadays. Custom-made implants with immediate loading overdenture are emerging as a solution for atrophic jaws rehabilitation. The authors describe the case of a 44-year-old male with a history of congenital dental agenesis. A previous oral rehabilitation with an all-on-6 type, implant-fixed mandibular overdenture, had failed due to peri-implantitis. The patient was successfully treated with bimaxillary custom-made subperiosteal implants with an innovative design, combining subperiosteal and endosseous support. The authors consider custom-made subperiosteal implants, in selected patients, present several advantages over classic bone-grafting plus endosseous implant-placement techniques such as (1) possibility of a single-stage procedure with immediate loading in atrophic jaws; (2) possible primary option to approach atrophic jaws as a simpler and less time-consuming technique; and (3) a valid rescue option for failed endosseous implants. More long-term studies with large samples of patients will be necessary to confirm previous assumptions.
Temporomandibular joint disorders (TMDs) are characterized by their multifactorial etiology and pathogenesis. A 3-year prospective study was conducted in a Portuguese TMDs department to study the prevalence of different TMDs signs and symptoms and their association with risk factors and comorbidities. Five hundred ninety-five patients were included using an online database: EUROTMJ. Most patients were female (80.50%), with a mean age of 38.20 ± 15.73 years. The main complaints were: (1) temporomandibular joint (TMJ) clicking (13.26%); (2) TMJ pain (12.49%); (3) masticatory muscle tension (12.15%). The main clinical findings were myalgia (74%), TMJ clicking (60–62%), and TMJ arthralgia (31–36%). Risk factors such as clenching (60%) and bruxism (30%) were positively associated with TMJ pain and myalgia. Orthodontic treatment (20%) and wisdom tooth removal (19%) were positively associated with TMJ clicking, while jaw trauma (6%), tracheal intubation (4%) and orthognathic surgery (1%) were positively associated with TMJ crepitus, limited mandibular range of motion, and TMJ pain, respectively. In total, 42.88% of TMDs patients had other associated chronic diseases, most of them were mental behavioral or neurodevelopmental disorders (33.76%), namely, anxiety (20%) and depression (13%). The authors also observed a positive association of mental disorders with the degree of TMJ pain and myalgia. The online database seems to be a relevant scientific instrument for healthcare providers who treat TMDs. The authors expect that the EUROTMJ database can serve as a milestone for other TMDs departments.
Background/Objectives: Temporomandibular disorders (TMD) encompass a range of musculoskeletal and neuromuscular conditions affecting the temporomandibular joint (TMJ) and associated structures. This cross-sectional study, conducted in a Portuguese TMD department, aimed to assess the relationship between malocclusion and TMD severity. Methods: Data on demographic variables, TMD clinical symptoms, and malocclusion classes were collected using the EUROTMJ database. The Chi-square test (χ2) identified associations, with their intensity measured by Cramér’s V (φc). Results: The study included 1170 patients (932 females and 238 males), with a mean age of 41.73 ± 16.80 years. Most patients exhibited Angle Class I malocclusion (85.5%), followed by Angle Class II (13.5%) and Angle Class III (1.1%). Class II malocclusion was associated with increased TMD severity (p < 0.001), higher myalgia levels (p = 0.002), more frequent disc displacement without reduction (p = 0.002) and lower maximum mouth opening values (Class II: 38.13 ± 7.78 mm, Class I: 39.93 ± 8.67 mm). Significant associations were also found between malocclusion type and arthralgia (p = 0.021), mouth-opening limitation (p = 0.016), and TMJ crepitus (p = 0.017). In cases of malocclusion, the presence of oral signs of bruxism explained the degree of myalgia, disc displacement, and severity (p = 0.003; p = 0.048; p = 0.045). Conclusions: This study highlights that (1) the most common type of dental malocclusion in TMD patients was Class I; (2) Class II malocclusion was associated with increased TMD severity and oral signs of bruxism; and (3) Class III was rarely observed in TMD consultation. The findings suggest that bruxism behavior in cases of malocclusion may be significant in TMD.