Thirty-nine temporomandibular joints (TMJ) from 20 patients with suspected internal derangements were imaged by a 1.5 T MR imager. The on-resonance binomial magnetization transfer contrast (MTC) pulse was applied to gradient echo images with a dual receiver coil (9 s/section). With the use of an opening device, a series of sequential images were obtained at increments of mouth opening and closing. The tissue signal intensities with (Ms) and without (Mo) MTC were measured and subjective image analysis was performed. Compared with the standard images, MTC technique provided selective signal suppression of disks. The average of Ms/Mo ratio of the disks (0.56) was lower than that of the retrodiskal pad (0.79) and of the effusion (0.89). With MTC technique, fluid conspicuity was superior to standard image. However, no significant superiority was found in disk definition subjectively.
ObjectiveReconstruction plates are used to treat patients with a segmental mandibular defect after oral cancer surgery. Reconstruction plate failure analysis has rarely focused on occlusion, which conducts a mechanical force to the mandible and the plate. To determine the prognostic factors, we retrospectively evaluated patients who underwent reconstruction of a mandibular segmental defect with a reconstruction plate and assessed the number of residual paired teeth.Material and MethodsFrom among 390 patients with oral cancer who visited University of Tsukuba Hospital (Tsukuba, Japan) between 2007 and 2017, we selected and analyzed the data of 37 patients who underwent segmental resection of the mandible and reconstruction with reconstruction plates. Prognostic factors evaluated were patient age, sex, TNM classification, plate manufacturer, treatment with radiotherapy or chemotherapy, whether the patient had diabetes or smoked, and whether the patient had a small number of residual paired teeth, plate length, and use of a fibular‐free flap. Among these 37 patients, eight reconstruction plates had intraoral or extraoral exposure and were removed in 5 years.ResultsKaplan–Meier and log‐rank analyses revealed that the prognosis for the 5‐year plate exposure‐free rate was significantly poorer for patients with a small number of residual teeth than for patients with no teeth or those with a large number of residual teeth (.01). Univariate Cox regression analysis revealed that a small number of residual teeth was a significant prognostic factor in the loss of a reconstruction plate (hazard ratio: 5.63; 95% confidence interval [1.10, 25.85]; .04).ConclusionsA small number of residual teeth after the segmental resection of oral cancer is significantly involved in reconstruction plate survival and may be important in predicting reconstruction plate prognosis.
Background: Synaptic adhesion molecules regulate synapse development and maintenance. Neurexins and neuroligins have been implicated in psychiatric disorders, and shown that they are related to vascular system and carcinomas in recent studies. In the present study we focused neurexin 1 and neuroligin1, and investigated the relationship between those two molecules expression and clinical features of oral cancer. Materials and methods: Fifty-six biopsy samples from oral squamous cell carcinomas (OSCCs) were analyzed semi quantitatively by immunohistochemistry. Correlations between the expression level of neurexin 1, neuroligin 1, p53, Ki67 and the clinical features of OSCCs were statistically analyzed. Results: The neurexin 1 expression group contained significantly advanced T (P < 0.05) and N classification positive cases (P < 0.01) by univariate analysis. Overall survival was compared with Kaplan-Meier analysis and the log rank statistic. The prognosis of neuroligin 1 expression group was significantly more favorable (P < 0.05). A Cox proportional hazards model was used to test the significance of survival time, and N classification positive (P < 0.05), neurexin 1 (P < 0.05) and neuroligin 1 (P < 0.01) were predictive factor for survival. Conclusions: Synaptic adhesive molecule could be useful prognosis factor for OSCC and may help to determine therapeutic policy.
A rare case of eosinophilic granuloma of the mandibular condyle in a 53-year-old woman is presented. The patient was referred to our department because of pain following discomfort in the left preauricular region. She had limitation of mouth opening without swelling or noise in the temporomandibular joint region. A panoramic radiograph showed an ill-defined lytic lesion occupying the left condyle. On MR imaging, the lesion was depicted as low signal intensity on T 1 -weighted images and as high signal intensity on T 2-weighted images and involved the condyle and lateral pterygoid muscle. The excised specimen obtained from the condyle was histologically diagnosed as eosinophilic granuloma. Mouth opening difficulty and pain resolved postoperatively. The condyle was regenerated 1 year after surgery, and there has been no evidence of recurrence for 3 years 10 months.
To identify whether the direction of disk flexure deformation predicts the prognosis in cases of anterior disk displacement without reduction of painful temporomandibular joint (TMJ), the relationship between the direction of flexure, observed on pseudodynamic magnetic resonance (MR) images, and the outcome of conservative treatment using a flat occlusal splint was analysed in 40 female patients who perceived occasional or constant pain at unilateral TMJ with disk displacement without reduction. From the MR findings, 20 patients were classified as having upward flexure deformation of the disk and 20 as having downward flexure deformation. Patients' TMJ pain, masticatory muscle pain, amount of maximal mouth opening, and MR findings were evaluated before treatment. All patients were treated with a flat occlusal splint for 6 months. The patients' signs and symptoms were analysed statistically within each group before treatment and 3 and 6 months afterwards, and were also compared between the upward and downward flexure groups. There was no statistical difference between the groups before treatment, except in the amount of maximal mouth opening and the extent of disk displacement. The upward flexure group had persistent TMJ pain and tendency of delayed alleviation of masticatory muscle pain compared with the downward flexure group, although maximal opening gradually increased in both groups. Thus, the direction of the flexure in deformation of the disk, which can be observed only with pseudodynamic MR imaging, may predict the prognosis of painful disk displacement without reduction following treatment with a flat occlusal splint.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.