Relationship between arthroscopic findings of synovitis and levels of tumour necrosis factor-alpha and matrix metalloproteinases in synovial lavage fluid from patients with unilateral high mandibular condyle fractures.

Arthrocentesis has an effect of washing out inflammatory products that accumulate in the joint compartment of a dysfunctional temporomandibular joint (TMJ). The procedure removes inflammatory cytokines, which are pain-causing substances, for early reduction of TMJ pain and quick recovery of jaw function, thus increasing the possibility of a successful rehabilitation. The aim of this study was to investigate the relationship between arthroscopy synovitis grade in patients with unilateral high condylar fractures and concentrations of the pro-inflammatory cytokines tumour necrosis factor (TNF)-alpha as well as of matrix metalloproteinases (MMPs) in washed-out synovial fluid (SF) samples obtained from those patients. A total of 26 patients with unilateral high condylar fractures who underwent arthrocentesis for a therapeutic purpose were examined. SF samples were collected before performing arthroscopy to determine synovitis grade. The detection rates and concentrations of TNF-alpha and MMPs were determined, and their association with synovitis grade was analysed. TNF-alpha was detected in 23 and MMP-3 in 22 of the TMJs. There was a correlation between synovitis grade and concentration of TNF-alpha in the fracture group. Furthermore, the concentrations of TNF-alpha and MMP-3 were significantly higher as compared to the control group, comprised of TMJs on the non-fracture side of the same patients, while a correlation was also noted between TNF-alpha concentration and synovitis grade in the fracture group. The present findings may provide a biological/biochemical rationale for arthrocentesis as a reasonable treatment modality for high condylar fractures.

Experimental comparison between tractional and compressive stress on temporomandibular joint.

OBJECTIVE: We experimentally compared the effects of compressive and tractional mechanical stress on the temporomandibular joint (TMJ) of rabbits to assess the etiology of progressive condylar resorption. MATERIALS AND METHODS: We performed a cortical osteotomy using custom-made devices that were lengthened by 0.25 mm every 12 h for 1 week after surgery. During this time, the rabbit TMJ was under compressive or tractional mechanical stress. The samples in each group were examined using micro-computed tomography and histological staining. RESULTS: Scores for the area of bone resorption were higher in the compressive group than in the tractional group. Moreover, scores for the depth of bone resorption were higher in the compressive group than those in the tractional group. We observed a significantly higher prevalence of resorption in the subcondylar bone in the compressive group than in the tractional group. There were substantially more cells that were positive for tartrate-resistant acid phosphatase in the compressive group than in the control and tractional groups. CONCLUSIONS: The outcomes here suggest that excessive mechanical stress, particularly compressive mechanical stress, may significantly affect morphological bone change findings in the TMJ.

Facilitation of bone resorption activities in synovial lavage fluid patients with mandibular condyle fractures.

The aim of this study was to investigate the bone resorption effect of the mediators delivered in joint cavity of patients with mandibular condyle fractures by detecting osteoclast markers using cellular biochemistry methods, and by analysing bone resorption activities via inducing osteoclast differentiation of the infiltrated cells from arthrocentesis. Sixteen joints in 10 patients with mandibular condyle fractures were evaluated. The control group consisted of synovial fluid (SF) samples from seven joints of four volunteers who had no clinical signs or symptoms involving the temporomandibular joint (TMJ) or disc displacement. We collected SF cells from all patients during therapeutic arthrocentesis. The infiltrating cells from TMJ SF were cultured, differentiated into tartrate-resistant acid phosphatase (TRAP)-positive osteoclast-like cells and examined bone resorption activities. We also investigated factors related to osteoclast induction of SF, using ELISA procedures. Osteoclast-like cells were induced from the SF cells obtained from all patients with condylar fractures. These multinucleated giant cells were positive for TRAP and actin, and had the ability to absorb dentin slices. The levels of macrophage colony-stimulating factor (M-CSF), prostaglandin E2 (PGE2), soluble form of receptor activator of nuclear factor kappa-B ligand (sRANKL) and osteoprotegerin (OPG), in SF samples from the patients, were significantly higher than in the controls. These findings indicate that bone resorption activities in SF from patients with mandibular condyle fractures were upregulated and may participate in the pathogenesis and wound healing.

Clinical comparison between arthrocentesis and conventional conservative treatment with maxillomandibular fixation for unilateral high condylar fractures.

This study aimed to compare the effects of arthrocentesis and conventional closed reduction for unilateral mandibular condyle fractures. A total of 30 patients with unilateral condylar fractures were evaluated. Patients with a high condylar fracture and magnetic resonance evidence of joint effusion (JE) were divided into two groups: those treated with intra-articular irrigation and betamethasone injection (group I) and those given conservative treatment and rigid maxillomandibular fixation (MMF) (group II). All patients were assessed for mandibular range of motion (ROM), protrusive movements, lateral excursion movements on the fractured and non-fractured sides, pain in the temporomandibular joint and malocclusion, both before and after treatment. There were no significant differences in regard to protrusion, lateral excursion movement and incidence of malocclusion at 12 months after treatment between the groups (P > 0.05). In group I, ROM and joint pain showed good improvement from the early stages of treatment, and those patients had better outcomes as compared to group II for those parameters at 1 and 3 months after injury. The present findings indicate that arthrocentesis may be more effective and provide faster healing than conventional closed reduction.

Weekly teriparatide injections successfully treated advanced bisphosphonate-related osteonecrosis of the jaws.

This study investigated whether weekly teriparatide (TPTD) injections are as effective as daily teriparatide injections for the treatment of stage 3 bisphosphonate-related osteonecrosis of the jaws (BRONJ) and compared serum markers of bone turnover between the two treatment regimens. Daily TPTD treatment has recently been reported to be effective for BRONJ, but there are no reports describing the effectiveness of weekly TPTD injections. We report two patients with stage 3 BRONJ. One patient was successfully treated with weekly TPTD injections and the other with daily TPTD injections. Changes in the levels of serum N-telopeptide of type I collagen (s-NTX) and serum N-terminal propeptide of type I collagen (P1NP) were studied. Two patients with stage 3 BRONJ that was refractory to conservative treatment were treated with TPTD. Their medical records were reviewed and the patients were interviewed. There was complete mucosal coverage of the intraoral defects after 3 months of TPTD treatment in both patients. Progressive bone regeneration in an area of mandibular fracture was identified after 4 months of treatment. The s-NTX level increased slightly in both patients. This is the first report of successful treatment of stage 3 BRONJ with weekly TPTD injections. Either daily or weekly TPTD injections may effectively treat stage 3 BRONJ and should be considered before or perhaps even in lieu of undertaking major resection and reconstruction.

Relationship between temporomandibular joint pain and magnetic resonance imaging findings in patients with temporomandibular joint disorders.

The purpose of this study was to evaluate abnormal magnetic resonance imaging (MRI) findings related to temporomandibular joint (TMJ) pain. This study included 245 joints of 152 patients with temporomandibular disorders with anterior disc displacement; of these, 129 joints had joint pain whereas 116 joints had no joint pain. MRI was used to evaluate the reduction of anterior disc displacement, joint effusion, mandible condylar morphology, bone marrow oedema of the mandibular condyle, and signal intensity of the posterior disc attachment (PDA) on fat-suppressed T2-weighted images. The odds ratio (OR) for each MRI variable for the pain group versus the no pain group was computed using logistic regression analysis. Univariate logistic regression analysis showed significant correlations between TMJ pain and all MRI findings. Multivariate logistic regression analysis showed significant correlations with joint effusion (P=0.03, OR 2.21), bone marrow oedema (P<0.001, OR 11.75), and signal intensity of the PDA (P<0.001, OR 6.21). These results suggest that bone marrow oedema, high signal intensity of the PDA on fat-suppressed T2-weighted images, and joint effusion, in descending order of influence, are factors related to TMJ pain.

Variety and complexity of fluorine-18-labelled fluoro-2-deoxy-D-glucose accumulations in the oral cavity of patients with oral cancers.

OBJECTIVES: To elucidate the points that require attention when interpreting fluorine-18-labelled fluoro-2-deoxy-d-glucose ((18)F-FDG)/positron emission tomography (PET) images by demonstration of (18)F-FDG accumulation in various areas of the oral cavity other than primary lesions in patients with oral cancers. METHODS: (18)F-FDG accumulations with a maximal standardized uptake value of over 2.5 in various areas of the oral cavity other than primary lesions were identified in 82 patients with oral cancers. RESULTS: (18)F-FDG/PET-positive areas, excluding primary tumours, included the front intrinsic muscles of the tongue (89.0%), upper and lower marginal parts of the orbicularis oris muscle (64.6%), sublingual glands, palatine tonsil, pharyngeal tonsil, and lingual tonsil. In addition, some areas in the jaws also showed accumulation. CONCLUSIONS: In patients with oral cancers, areas of (18)F-FDG accumulation in the oral cavity should be precisely identified and appropriately diagnosed, because accumulations can be seen in areas other than the primary tumour.