Hyaluronic Acid/Platelet-Rich Plasma Mixture Improves Temporomandibular Joint Biomechanics: A Systematic Review.

Hyaluronic acid (HA) is the main component of the temporomandibular joint (TMJ) synovial fluid. Arthritis in temporomandibular disorders (TMDs) disrupts HA metabolism, resulting in shorter polymeric chain predominance and increased friction. Intra-articular injections of HA supplement the larger molecules of this glycosaminoglycan, and the platelet-rich plasma (PRP) delivered in this way releases growth factors, suppressing inflammation. This PRISMA-compliant PROSPERO-registered (CRD42024564382) systematic review aimed to assess the validity of mixing HA with PRP in the injectable treatment of TMJ disorders. We searched the medical literature for eligible randomized clinical trials using BASE, Google Scholar, PubMed and Scopus engines on 9 May 2024, with no time frame limit. Selected reports were assessed for risk of bias using the Cochrane RoB2 tool. Numerical data were collected on articular pain and mandibular mobility. We provided mean differences from baseline and between study and control groups at each observation point. The efficacy of TMD treatment with HA/PRP versus HA or PRP alone was assessed meta-analytically. Of 171 identified records, we selected 6 studies. In the 6-month follow-up, the mean advantage of PRP supplementation with HA was 2.52 (SE = 2.44; d = 0.83) mm and the benefit of adding PRP to HA was 1.47 (SE = 2.68; d = 0.34) mm in mandibular abduction. The pain-improvement scores were -1.33 (SE = 1.02; d = -1.05) and -1.18 (SE = 0.92; d = 0.80), respectively. Presumably, the HA/PRP range of therapeutic efficiency includes cases non-respondent to HA or PRP alone.

The effect of celecoxib in traumatic heterotopic ossification around temporomandibular joint in mice.

OBJECTIVE: In this study, the role of inflammation in traumatic heterotopic ossification around temporomandibular joint (THO-TMJ), as well as the preventive and treatment effect of celecoxib in THO-TMJ both in vivo and in vitro were explored. DESIGN: A surgically-induced THO-TMJ mouse model and a co-culture model of ATDC-5 or MC3T3-E1 and RAW-264.7 cells were used in this study for in vivo and in vitro research. RESULTS: A series of inflammatory factors, such as CD3, CD68, CD20, IL-10, IL-6 and TNF-α, were activated 48 h after trauma in a THO-TMJ model. Local trauma initiated systemic inflammatory responses as well as T cell- and macrophage-mediated local inflammatory responses around TMJ. In addition, expression of COX-2 was significantly elevated. The findings also showed that local injection of celecoxib could effectively alleviate the inflammatory response around TMJ at the early stage of trauma and inhibit the formation of THO-TMJ in vivo. Meanwhile, celecoxib could inhibit chondrogenic differentiation of ATDC-5 and osteogenic differentiation of MC3T3-E1 under inflammatory condition in vitro. Furthermore, celecoxib could inhibit the expression of Bmpr1b in the injured condylar cartilage at the initiation stage of THO-TMJ, which implied that Bmpr1b expressed by the residual condylar cartilage might be related to the pathogenesis of THO-TMJ. CONCLUSIONS: Inflammation played a crucial role in the pathogenesis of THO-TMJ, and anti-inflammation might be a possible choice to inhibit THO-TMJ, which provided scientific clues for the mechanisms, pharmacotherapy and molecular intervention of THO-TMJ.

HDAC10 upregulation contributes to interleukin 1ß-mediated inflammatory activation of synovium-derived mesenchymal stem cells in temporomandibular joint.

Histone deacetylases (HDACs) are important in chronic inflammation, and inflammatory responses affect synovium-derived mesenchymal stem cell (SMSC) function in temporomandibular joint repair. However, the effect of HDACs on SMSC inflammatory activation remains unclear. In this study, temporomandibular joint fibroblast-like synoviocytes obtained from osteoarthritis patients met the minimal mesenchymal stem cell criteria. Interleukin 1ß (IL-1ß) upregulated IL-6 and IL-8 expression in SMSCs through nuclear factor-κB (NF-κB) pathway activation. IL-6 and IL-8 upregulation were blocked by broad-acting HDAC inhibitors SAHA and LBH589. MC1568 alleviated IL-1ß activation of SMSCs, whereas CI994 and FK228 produced a minimal or opposite effect in vitro. We also found HDAC10 was highly associated with localized IL-1ß expression in vivo and in vitro. HDAC10 knockdown alleviated IL-1ß-mediated SMSC activation and blocked NF-κB pathway activation. Conversely, HDAC10 overexpression promoted IL-6 and IL-8 expression and IL-1ß-mediated NF-κB pathway activation. In conclusion, HDAC10 upregulation contributed to IL-1ß-mediated inflammatory activation of SMSCs, indicating that HDAC10 may be a novel therapeutic target.

Comparison of the Efficacies of Dry Needling and Botox Methods in the Treatment of Myofascial Pain Syndrome Affecting the Temporomandibular Joint.

BACKGROUND: To compare the efficacies of botulinum toxin-A injection and dry needling methods in the treatment of patients with myofascial pain syndrome (MPS) in the temporomandibular joint (TMJ). METHODS: In this prospective study, 40 MPS patients (29 women, 11 men) were randomly assigned to abobotulinum toxin-A injection (Group 1, n = 20) or dry needling (Group 2, n = 20) groups. Pain, crepitation, functional limitation, maximum mouth opening, jaw strength were evaluated at baseline and 6 weeks, and the results in both groups were compared. RESULTS: The average age of the authors' patients was 33.8±8.1. There was a remarkable difference between 2 groups regarding visual analog scale for TMJ pain at rest (P = 0.048). The pain at rest was relieved more effectively in Group 2 at the end of 6 weeks. Improvement in jaw protrusion angles on the right (P = 0.009) and left (P = 0.002) sides was more evident in Group 2 after 6 weeks. There were significant pain relief and functional improvement after treatment in both groups. In Group 2, recovery of the TMJ function was more obvious in 6 weeks following dry needling (P = 0.002). CONCLUSION: The authors suggest that abobotulinum toxin-A injection and dry needling yield satisfactory therapeutic outcomes regarding pain relief and restoration of function in patients with MPS involving TMJ. Further multicentric, randomized, controlled trials on larger series are warranted to obtain more accurate and reliable information.

Temporomandibular steroids in patients with tinnitus: Only on indication.

INTRODUCTION: Patients with tinnitus without an identifiable cause may have temporomandibular joint dysfunction and can be treated by an intra-articular injection of steroids. OBJECTIVES: The aim of this study was to determine the efficacy of temporomandibular steroids for treating patients with tinnitus, and more specifically, to assess the parameters associated with a long-term benefit in order to improve patient selection. DESIGN: Subjects were 70 consecutive patients who came to our clinic from October 2016 to October 2018 for consultations on their tinnitus that persisted for one month or longer and were treated with an intra-articular injection of the temporomandibular joint with steroids. Patients charts, cervical spine radiographs and audiogram were reviewed retrospectively and data from these patients were recorded. An independent observer conducted a long-term follow-up assessment of the therapy by telephone interview. RESULTS: Relief of tinnitus at seven-week follow-up was achieved in 20% of the patients treated with temporomandibular steroids. At 18 months, 50% of the patients successfully treated with temporomandibular steroids for tinnitus still experienced a benefit. Adverse events of the temporomandibular steroids reported at 7 weeks of follow-up were an increase of the intensity of their tinnitus in 11% of the patients and in 3% of the patient's side-effects of the steroids. Patients with temporomandibular disorders as cause of their tinnitus were identified by the presence of unilateral tinnitus in combination with cervical pain. In patients with unilateral tinnitus together with cervical pain, 53% of them had a reduction of their tinnitus at 7 weeks following treatment with temporomandibular steroids and for 40% of them the reduction of the tinnitus was 50% or more. An increase in the intensity of their tinnitus as adverse effect occurred in 7% of the patients in this group. CONCLUSIONS: Temporomandibular steroids can be a useful alternative for patients with tinnitus with a long term effect. However, patient selection is of vital importance, since patients with unilateral tinnitus and cervical pain respond the most to this therapy. Moreover, patient without these symptoms risk worsening the tinnitus. A prospective study should further evaluate these findings.

Evaluation of the Efficacy of Different Concentrations of Dextrose Prolotherapy in Temporomandibular Joint Hypermobility Treatment.

PURPOSE: The aim of this study was to compare and evaluate the efficacy of different concentrations of dextrose prolotherapy for the treatment of temporomandibular joint (TMJ) hypermobility. PATIENTS AND METHODS: A prospective, randomized clinical trial including patients with subluxation or dislocation was performed. The study comprised 40 patients. Patients were randomly divided into 4 groups: control group, 10% dextrose, 20% dextrose, and 30% dextrose group. Patients in all groups received injections into 4 different areas of each TMJ in 4 sessions at monthly intervals. Visual analog scale of TMJ pain intensity, maximum mouth opening (MMO), joint sounds, and frequency of luxations were recorded preoperatively and postoperatively after 1 month of last injection. The collected data were then statistically analyzed. RESULTS: Each group showed postoperatively significant improvement in TMJ pain, significant decrease in both MMO and joint sound. Besides that, TMJ locking was not observed in any patient during the follow-up period. There were no statistically significant differences throughout the study intervals between the groups. CONCLUSION: It was concluded that there was no significant difference between control group and dextrose groups and there is no superiority of any concentration of dextrose over the others in TMJ prolotherapy, and all treatment procedures were efficient in improvement of clinical symptoms related to TMJ hypermobility. If dextrose is used as a proliferant, it can be said that 10% dextrose can be sufficient in TMJ hypermobility treatment.

Effects of glucosamine supplements on painful temporomandibular joint osteoarthritis: A systematic review.

The purpose of this study was to systematically review the literature for studies that assessed the effects of glucosamine supplements (GS) on pain and maximum mouth opening (MMO) restriction compared to other therapies, placebo or no intervention on painful temporomandibular joint osteoarthritis (TMJ OA). Randomised controlled trials were selected in a two-phase process. Seven electronic databases, in addition to three grey literature databases, were searched. Risk of bias was assessed using the Cochrane Collaboration's tool for assessing risk of bias in randomised trials. Twelve potentially eligible studies were identified, from which three were finally included. Furthermore, two were categorised at low risk and one at high risk of bias. Intervention groups were treated with glucosamine-sulphate, while controls were treated with placebo or ibuprofen. In two studies, GS were equally effective regarding pain reduction and mouth opening improvement compared to ibuprofen taken two or three times a day over 12 weeks; however, one study did not find significant differences in follow-up evaluations concerning these clinical variables in both glucosamine and placebo groups administered over six weeks. There is very low evidence regarding GS therapeutic effects on TMJ OA. Considering a follow-up of 12 weeks, GS were as effective as ibuprofen taken two or three times a day. However, over six weeks of medication intake, GS were not superior to placebo. Still, included studies presented major drawbacks, and therefore, conclusions must be interpreted with caution.

[Intra-articular steroid and hyaluronic acid treatment of internal derangement of the temporomandibular joint]. / Az állkapocsízületi károsodás kezelése szteroiddal, illetve hialuronsavval.

INTRODUCTION: Derangement of the temporomandibular joint complicates everyday life, due to the masticatory malfunction and the continuous pain sensation of the head and facial region. The therapy is multidisciplinary and varying. In case of the inefficiency of conservative therapy, minimally invasive intervention is needed with intraarticular injection. AIM: The aim of our study was to examine whether hyaluronic acid injection is more beneficial compared to corticosteroid in 37 joints. We also examined whether the efficacy of the therapy is influenced by hyaluronic acid molecular weight and the used protocol. METHOD: Wilkes stage, maximal mouth opening and the Visual Analogue Scale were determined pre-operatively and 6 months later. Corticosteroid application was performed once, hyaluronic acid was injected on a weekly bases 3 times in a row, by use of low (6-10 × 105 dalton) or high molecular weight (24-36 × 105 dalton) preparations. RESULTS: The medical state of the patients treated with corticosteroid temporarily improved, but the symptoms returned. Due to hyaluronic acid treatment, significant improvement was revealed in all parameters (pwilkes<0.0001; pmouth-opening = 0.0002; pVAS<0.0001). There was no significant relapse (T = 2.05). The third administration of hyaluronic acid resulted in a significant improvement of the Visual Analogue Scale compared to the first and second injection (T3.-1. = 20.37; T3.-2. = 9.57). CONCLUSIONS: Comparing the two agents we can state that hyaluronic acid was significantly more effective and its application for three times seems to be the most effective treatment decreasing the symptoms. The high molecular weight solution was more effective in increasing mouth opening. In contrast to hyaluronic acid, corticosteroid had no prolonged effect in higher Wilkes stages. Orv Hetil. 2018; 159(36): 1475-1482.

Fas/S1P1 crosstalk via NF-κB activation in osteoclasts controls subchondral bone remodeling in murine TMJ arthritis.

Enhanced turnover of subchondral trabecular bone is a hallmark of rheumatoid arthritis (RA) and it results from an imbalance between bone resorption and bone formation activities. To investigate the formation and activation of osteoclasts which mediate bone resorption, a Fas-deficient MRL/lpr mouse model which spontaneously develops autoimmune arthritis and exhibits decreased bone mass was studied. Various assays were performed on subchondral trabecular bone of the temporomandibular joint (TMJ) from MRL/lpr mice and MRL+/+ mice. Initially, greater osteoclast production was observed in vitro from bone marrow macrophages obtained from MRL/lpr mice due to enhanced phosphorylation of NF-κB, as well as Akt and MAPK, to receptor activator of nuclear factor-κB ligand (RANKL). Expression of sphingosine 1-phosphate receptor 1 (S1P1) was also significantly upregulated in the condylar cartilage. S1P1 was found to be required for S1P-induced migration of osteoclast precursor cells and downstream signaling via Rac1. When SN50, a synthetic NF-κB-inhibitory peptide, was applied to the MRL/lpr mice, subchondral trabecular bone loss was reduced and both production of osteoclastogenesis markers and sphingosine kinase (Sphk) 1/S1P1 signaling were reduced. Thus, the present results suggest that Fas/S1P1 signaling via activation of NF-κB in osteoclast precursor cells is a key factor in the pathogenesis of RA in the TMJ.

Sex differences in the estrogen-dependent regulation of temporomandibular joint remodeling in altered loading.

OBJECTIVE: Temporomandibular joint (TMJ) diseases predominantly afflict women, suggesting a role of estrogen in the disease etiology. Previously, we determined that decreased occlusal loading (DOL) inhibited collagen type II (Col2) expression in the mandibular condylar cartilage (MCC) of female wild-type (WT) mice whereas no change was observed in males. This decrease in chondrogenesis was abolished by estrogen receptor beta (ERß) deficiency in females. Therefore, the goal of this study was to examine the role of estradiol - ERß signaling in mediating DOL effects in male mice to further decipher sex differences. METHODS: Male 21 day-old WT and ERßKO male mice were treated with either placebo or estradiol and exposed to normal or DOL for 4 weeks. Cartilage thickness and cell proliferation, gene expression and immunohistochemistry of chondrogenic markers and estrogen receptor alpha (ERα), and analysis of bone histomorphometry via microCT were completed to ascertain the effect of estradiol on DOL effects to the TMJ. RESULTS: ERßKO male mice lack a MCC phenotype. In both genotypes, estradiol treatment increased Col2 gene expression and trabecular thickness. DOL in combination with estradiol treatment caused a significant increase in Col2 gene expression in both genotypes. CONCLUSIONS: The sex differences in DOL-induced inhibition of Col2 expression do not appear to be mediated by differences in estradiol levels between male and female mice. Greater understanding on the role of estrogen and altered loading are critical in order to decipher the sex dimorphism of TMJ disorders.

Estradiol promotes M1-like macrophage activation through cadherin-11 to aggravate temporomandibular joint inflammation in rats.

Macrophages play a major role in joint inflammation. Estrogen is involved in rheumatoid arthritis and temporomandibular disorders. However, the underlying mechanism is still unclear. This study was done to verify and test how estrogen affects M1/M2-like macrophage polarization and then contributes to joint inflammation. Female rats were ovariectomized and treated with increasing doses of 17ß-estradiol for 10 d and then intra-articularly injected with CFA to induce temporomandibular joint (TMJ) inflammation. The polarization of macrophages and expression of cadherin-11 was evaluated at 24 h after the induction of TMJ inflammation and after blocking cadherin-11 or estrogen receptors. NR8383 macrophages were treated with estradiol and TNF-α, with or without blocking cadherin-11 or estrogen receptors, to evaluate the expression of the M1/M2-like macrophage-associated genes. We found that estradiol increased the infiltration of macrophages with a proinflammatory M1-like predominant profile in the synovium of inflamed TMJ. In addition, estradiol dose-dependently upregulated the expressions of the M1-associated proinflammatory factor inducible NO synthase (iNOS) but repressed the expressions of the M2-associated genes IL-10 and arginase in NR8383 macrophages. Furthermore, estradiol mainly promoted cadherin-11 expression in M1-like macrophages of inflamed TMJ. By contrast, blockage of cadherin-11 concurrently reversed estradiol-potentiated M1-like macrophage activation and TMJ inflammation, as well as reversed TNF-α-induced induction of inducible NO synthase and NO in NR8383 macrophages. The blocking of estrogen receptors reversed estradiol-potentiated M1-like macrophage activation and cadherin-11 expression. These results suggested that estradiol could promote M1-like macrophage activation through cadherin-11 to aggravate the acute inflammation of TMJs.

Chitosan-Based Thermosensitive Hydrogel for Controlled Drug Delivery to the Temporomandibular Joint.

Intra-articular injections of hyaluronic acid (HA) and corticosteroids have been extensively used in treating temporomandibular disorders. However, rapid clearance from the site of injection is a major concern that is commonly managed by frequent dosing, which is not without complications. This study aimed to determine the suitability of thermosensitive chitosan-based hydrogels for intra-articular controlled release of drugs in the rabbit temporomandibular joint (TMJ). A series of hydrogels were prepared using different chitosan (Ch) to ß-glycerophosphate (ß-GP) ratios. The gelation time, swelling ratio, the shape, and surface morphology of the prepared gels were investigated to select the formulation with optimum characteristics. The left TMJ in 13 adult male New Zealand white rabbits was injected with 0.2 mL of Chitosan/ß-glycerophosphate/HA while the right TMJ was injected with 0.2 mL of control solution of HA. Hyaluronic acid concentrations in experimental and control groups were measured using Hyaluronan Quantikine Enzyme-Linked Immunosorbent Assay Kit. In vitro characterization showed that both the Ch:ß-GP ratio and incorporation of HA had a significant effect on gelation time, degree of swelling, and surface morphology of the hydrogels. No morphological changes were observed in the joints in both groups. The mean concentration of HA in the experimental joints after 7 days (1339.79 ±â€Š244.98 µg/g) was significantly higher than that in the control (474.52 ±â€Š79.36 µg/g). In conclusion, the chitosan-based thermosensitive hydrogel can be considered as a promising controlled drug release system to the TMJ in a rabbit model that would potentially overcome many of the current limitations of intra-articular formulations.

Effect of methylprednisolone, hyaluronic acid and pioglitazone on histological remodeling of temporomandibular joint cartilage in rabbits affected by drug-induced osteoarthritis.

BACKGROUND: The aims of this study were to assess the anti-degenerative effects of pioglitazone and to compare these effects with those of methylprednisolone and hyaluronic acid on drug-induced osteoarthritis in rabbits' temporomandibular joint cartilage. MATERIAL AND METHODS: The experiment was conducted on 40 Californian white rabbits. Degenerative changes were induced by intra-articular injections of papain. Subsequently, all of the animals were randomly assigned to one of four groups: 1) a control group that received no medications; 2) a group treated with 4 intra-articular injections of 2 mg (0.2 ml) of hyaluronic acid at weekly intervals; 3) a group treated with 4 intra-articular injections of 2 mg (0.1 ml) of methylprednisolone at weekly intervals; 4) a group administered pioglitazone orally in daily doses of 2 mg/kg of body weight. Four weeks after the beginning of drug administration, the rabbits were sacrificed. Sagittal sections of the intra-articular cartilage (discs) and mandibular condyles were stained with hematoxylin and eosin by the PAS technique and with van Gieson's solution. Histologic examinations, as well as cartilage thickness and number of cell layers measurements, were performed. RESULTS: Histologic assessment in cases of arthritis-associated pathologies revealed that changes occurred most frequently in the control group and least frequently in the pioglitazone group. There were no differences in the histological structures of the intra-articular discs. Cartilage thickness measurements demonstrated the thinnest cartilage in group 2 and the thickest in group 3. Analysis of cell layer numbers showed the most numerous layers in the pioglitazone group and the least in the control group. CONCLUSION: Pioglitazone and hyaluronic acid showed anti-degenerative properties compared to methylprednisolone in an animal model.

Laser therapy reduces gelatinolytic activity in the rat trigeminal ganglion during temporomandibular joint inflammation.

OBJECTIVES: To investigate whether low-level laser therapy (LLLT) alters the expression and activity of MMP-2 and MMP-9 in the trigeminal ganglion (TG) during different stages of temporomandibular joint (TMJ) inflammation in rats. It also evaluated whether LLLT modifies mechanical allodynia and orofacial hyperalgesia. MATERIALS AND METHODS: Wistar rats (±250 g) were divided into groups that received saline (SAL) or complete Freund's adjuvant (CFA, 50 µl) in the TMJ, and that later underwent LLLT (20 J cm(-2) ) at their TMJ or not (groups SAL, SAL + LLLT, CFA, and CFA + LLLT). LLLT was applied on days 3, 5, 7, and 9 after SAL or CFA. Mechanical allodynia was evaluated on days 1, 3, 5, 7, and 10; orofacial hyperalgesia was assessed on day 10. Gelatin zymography and in situ zymography aided quantification of MMPs in the TG. RESULTS: Low-level laser therapy abolished the reduction in the mechanical orofacial threshold and the increase in orofacial rubbing during the orofacial formalin test induced by CFA. LLLT also decreased the CFA-induced rise in the levels of MMP-9 and MMP-2 as well as the gelatinolytic activity in the TG. CONCLUSION: Low-level laser therapy could constitute an adjuvant therapy to treat temporomandibular disorders and prevent inflammation-induced alterations in the levels of MMP-2 and MMP-9 and in the gelatinolytic activity in TGs.

Effect of methotrexate on the mandibular development of arthritic rabbits.

INTRODUCTION: Juvenile idiopathic arthritis affecting the temporomandibular joint (TMJ) can cause severe disturbances of the mandibular development. Methotrexate (MTX) is often administered as a common used remission-inducing agent to treat this disease. The aim of this study was to investigate the effect of low dose MTX on the mandibular growth in arthritic rabbits. SUBJECTS AND METHODS: Eighteen 10-week-old female New Zealand white rabbits were randomly assigned to three groups with six animals in each group. After being sensitized to ovalbumin (OA), the first and the second group received intra-articular injections with OA. The first group remained untreated, the second was treated by weekly injections of MTX. Cephalograms were taken from each animal at 10, 13, 16, 19, and 22 weeks of age and six mandibular distances measured. RESULTS: All distances showed an increase between 10 and 20 per cent, whereas growth was more accentuated in the sagittal dimension. Significant differences in the overall growth could be observed between the arthritic and the control animals and less accentuated between the arthritic and the MTX animals. In contrast, existing differences between the groups were not significant during the intervals, but time had the greatest influence on mandibular growth. CONCLUSIONS: MTX seems to have a positive impact on growth in rabbits suffering from experimental arthritis of the TMJ.

Estrogen via estrogen receptor beta partially inhibits mandibular condylar cartilage growth.

OBJECTIVE: Temporomandibular joint (TMJ) diseases predominantly afflict women, suggesting a role for female hormones in the disease process. However, little is known about the role of estrogen receptor (ER) signaling in regulating mandibular condylar cartilage growth. Therefore, the goal of this study was to examine the effects of altered estrogen levels on the mandibular condylar cartilage in wild type (WT) and ER beta Knockout (KO) mice. MATERIALS AND METHODS: 21-day-old female WT (n = 37) and ER beta KO mice (n = 36) were either sham operated or ovariectomized, and treated with either placebo or estradiol. The mandibular condylar cartilage was evaluated by histomorphometry, proliferation was analyzed by double ethynyl-2'-deoxyuridine/bromodeoxyuridine (EdU/BrdU) labeling, and assays on gene and protein expression of chondrocyte maturation markers were performed. RESULTS: In WT mice, ovariectomy caused a significant increase in mandibular condylar cartilage cell numbers, a significant increase in Sox9 expression and a significant increase in proliferation compared with sham operated WT mice. In contrast, ovariectomy did not cause any of these effects in the ER beta KO mice. Estrogen replacement treatment in ovariectomized WT mice caused a significant decrease in ER alpha expression and a significant increase in Sost expression compared with ovariectomized mice treated with placebo. Estrogen replacement treatment in ovariectomized ER beta KO mice caused a significant increase in Col2 expression, no change in ER alpha expression, and a significant increase in Sost expression. CONCLUSION: Estrogen via ER beta inhibits proliferation and ER alpha expression while estrogen independent of ER beta induces Col2 and Sost expression.

Effects of zoledronic acid on physiologic bone remodeling of condylar part of TMJ: a radiologic and histomorphometric examination in rabbits.

OBJECTIVE: The purpose of the present study is to evaluate the effects of systemically administered zoledronic acid (ZA) on the physiological bone remodeling and the microarchitectural parameters of the condylar part of TMJ in a rabbit model. STUDY DESIGN: Thirty skeletally mature male New Zealand white rabbits were randomly divided into two groups. The experimental group was administered an intravenous, single dose of 0.1 mg/kg ZA diluted with 15 mL of saline in a 15-minute perfusion with an infusion pump. The control group was administered only saline infusion for 15 minutes. All rabbits were sacrificed on the 21st postoperative day. Radiodensitometric and histomorphometric examinations were performed on the harvested mandibular condyles. The data were analyzed statistically. RESULTS: Radiodensitometric findings showed that ZA treatment resulted in a significant increase in the mineralization of mandibular condyle. This result was supported by the histomorphometric findings. CONCLUSION: The present study has revealed that a temporary delay in the physiological bone remodeling using single dose of ZA increases bone mineral content and makes the microarchitecture of the mandibular condyle more compact. These effects may be regarded as base data and considered in numerous clinical situations including TMJ.

[HYALURONIC ACID: STRUCTURE, FUNCTIONS, THE POSSIBILITES OF APPLYING IN THE COMPLEX TREATMENT OF THE TEMPOROMANDIBULAR JOINT DISEASES. A REWIEW].

Over the last decade the use of hyaluronic acid has become increasingly important in treatment of degenerative disorders of the temporomandibular joint. Urgency is caused by numerous studies in biology and pharmacology on structure and function of hyaluronic acid and its influence on the processes of repair damaged bone and articular cartilage restoration, as well as the positive long-term results of treatment in this group of patients.

Effects of Glucosamine in the Temporomandibular Joint Osteoarthritis: A Review.

Osteoarthritis in the temporomandibular joint (TMJ) is a chronic disease characterized by irreversible damage to articular surfaces, including inflammation, loss of articular cartilage, and subchondral bone alterations, which would be radiographically evident only in later stages. Symptomatic slow-acting so-called nutraceutical drugs have been proposed as a treatment for osteoarthritis in comparison to non-steroidal anti-inflammatory drugs (NSAID) because of their appreciable safety profile even in long-term intake. Glucosamine, being one among them, proved highly efficient in knee osteoarthritis. However, its application in TMJ osteoarthritis dates back only to 2001 and is still inconclusive in its efficiency even with systematic reviews, in restoring the structural and functional aspects of damaged TMJ. Glucosamine, being a natural compound and also a contributor to building the matrix of articular cartilage, can be utilized effectively for TMJ osteoarthritis as an adjunct along with other conventional treatment modalities available till now, which also have moderate prognosis in most of the clinical scenarios. This review summarizes data relating to the mechanism of osteoarthritis and its management using glucosamine formulations. The beneficial effects of glucosamine on the pathophysiology of TMJ osteoarthritis are possibly due to its contribution to hyaluronic acid regulation and in establishing a proper balance between anabolism/catabolism in the articular tissues.

Does intra-articular injection of platelet-rich plasma/platelet-rich fibrin improve outcomes after temporomandibular joint arthrocentesis? A systematic review and meta-analysis.

Platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) have been used as adjuncts to temporomandibular joint (TMJ) arthrocentesis but without any high-quality evidence. This systematic review collated data from published randomised controlled trials (RCTs) to provide level-1 evidence on its efficacy. Trials published on the databases of PubMed, Scopus, Embase, CENTRAL, and Web of Science up to 4 August 2023 and comparing intra-articular PRP/PRF with control after TMJ arthrocentesis were eligible. Primary outcomes were pain and maximal mouth opening (MMO). Twelve RCTs were included. Pooled analysis showed that pain scores were significantly reduced with the use of PRP/PRF as compared with control at one month (MD: -0.96 95% CI: -1.58 to -0.35 I2 = 86%), three months (MD: -1.22 95% CI: -1.86 to -0.59 I2 = 85%), and ≥six months (MD: -1.61 95% CI: -2.22 to -1.00 I2 = 88%). Similarly, MMO was significantly improved in the PRP/PRF group at one month (MD: 2.40 95% CI: 1.02 to 3.77 I2 = 88%), three months (MD: 3.17 95% CI: 1.63 to 4.72 I2 = 91%), and ≥six months (MD: 2.98 95% CI: 1.86 to 4.10 I2 = 75%) as compared with the control group. Subgroup analysis for PRP and PRF failed to show any difference in outcomes. Moderate quality evidence suggests that PRP and PRF may significantly improve pain and MMO when used as adjuncts to TMJ arthrocentesis. Due to the small effect size, the clinical significance of the results is questionable. The high heterogeneity in PRP/PRF preparation methods is a significant limitation.