Sjögren's syndrome: a case report and review of the literature.

The manifestations and complications of Sjögren's syndrome are important to know, and dentists can play an important role in the detection of this disease. This report highlights such a case.

Sjogren's syndrome: a case report and review of the literature / El síndrome de Sjögren: reporte de caso y revisión de la literatura

The manifestations and complications of Sjögren s syndrome are important to know, and dentists can play an important role in the detection of this disease. This report highlights such a case.

Es importante conocer las manifestaciones y complicaciones del síndrome de Sjögren, y los dentistas pueden jugar un papel importante en la detección de esta enfermedad. Este reporte documenta este caso.

UVC radiation-induced effect on human primary thyroid cell proliferation and HLA-DR expression.

The aim of this study was to examine how UVC irradiation will affect normal human thyroid cell proliferation and HLA-DR expression. Primary human thyroid cells were exposed to UVC (254 nm wavelength) irradiation. In some experiments 0.5 mM buthionine sulfoximine (BSO) was added. Apoptosis was detected measuring annexin V, proteins involved in apoptotic process (p53, Bax, Bcl-2, caspase 3, and 9) by immunoblot analysis and HLA-DR expression by FACS. UVC induced a cell cycle arrest in G0/G1 phase in the first 24 h, accumulation of cells in the S phase 72 h after treatment, and an increase of apoptotic cells. BSO pretreatment showed an earlier appearance and a higher percentage of apoptosis. p53, caspase 3 and 9 were increased, while Bax and Bcl-2 were decreased. We also observed a transient significant increase in HLA-DR expression. UVC inhibited cell proliferation and induced apoptosis in normal human primary thyroid cells. An inhibitor of glutathione synthesis induced an earlier appearance and higher percentage of apoptosis suggesting that oxidative stress may play a role. Apoptotis involved components of the intrinsic mitochondrial pathway. A transient increase in HLA-DR expression after UVC irradiation could play a role in inducing AITD.

The nuclear ceramide/diacylglycerol balance depends on the physiological state of thyroid cells and changes during UV-C radiation-induced apoptosis.

Intranuclear lipid metabolism modifications in relation to cell proliferation and/or apoptosis were demonstrated in hepatocytes. The aim of this study was to establish whether nuclear lipid metabolites influence cell function in different experimental models using a rat thyroid cell line (FRTL-5) treated with UV-C radiation. After UV-C irradiation cells proliferate and undergo apoptosis in the presence of thyrotropin, are quiescent and resistant to radiation-induced apoptosis in its absence and finally are proapoptotic for nutrition withdrawal. In nuclei purified from proliferating cells, irradiation stimulates neutral-sphingomyelinase activity and inhibits sphingomyelin-synthase, phosphatidylcholine-specific phospholipase C and phosphatidylinositol-specific phospholipase C activity with a consequent increase in the ceramide/diacylglycerol ratio. This effect is marked in proapoptotic cell nuclei and low in quiescent cell nuclei. In conclusion, UV-C radiation induces apoptosis, modifying nuclear lipid metabolism in relation to the physiological state of cells.

Differential expression of the components of the plasminogen activating system in human thyroid tumour derived cell lines and papillary carcinomas.

We characterised the expression of the plasminogen activators (uPA and tPA), the uPA receptor (uPAR) and the PAs inhibitors (PAI-1 and PAI-2) in human thyroid cell lines derived from normal thyroid, follicular adenoma, follicular, papillary and anaplastic carcinomas. Urokinase PA activity was detected in the supernatant of normal thyrocytes and augmented in those of all tumour cells. Quantitative RT-PCR analysis showed that uPA, uPAR and PAI-1 mRNAs increased in all carcinoma cells. Similar results were found in 13 papillary thyroid carcinoma (PTC) tissues which were mirrored in Western blot experiments. A correlation was found between tumour size and uPA mRNA increase, and higher levels of uPA and uPAR mRNAs were found in metastatic PTC. In conclusion, thyroid carcinoma cell lines and PTC overexpress uPA, uPAR and PAI-1 and the correlation of uPA and its cognate receptor with tumour size and metastasis may suggest their potential prognostic relevance in thyroid cancer.

Relationship of condylar position to disc position and morphology.

INTRODUCTION/OBJECTIVE: The purpose of this study was to assess whether condylar position, as depicted by magnetic resonance imaging, was an indicator of disc morphology and position. METHODS AND MATERIAL: One hundred and twenty two TMJs of 61 patients with temporomandibular joint disorder were examined. Condylar position, disc deformity and degree of anterior disc displacement were evaluated by using magnetic resonance imaging. RESULTS AND DISCUSSION: Posterior condyle position was found to be the main feature of temporomandibular joints with slight and moderate anterior disc displacement. No statistical significance was found between the condylar position, and reducing and nonreducing disc positions. On the other hand, superior disc position was found to be statistically significant for centric condylar position. CONCLUSION: It was concluded that posterior condyle position could indicate anterior disc displacement whereas there was no relation between the position of condyle and the disc deformity.

Relationship between the TMJ disc and condyle position on MRI and occlusal contacts on lateral excursions in TMD patients.

Confusion about the relationship between dental occlusion and the temporomandibular disorders (TMD) has been evident in the literature for many years. Previous studies have supported the concept of a multifactorial aetiology of TMD, the occlusal factor in general being of minor importance. The purpose of the study was to investigate the relationship between condyle and disc positions and occlusal contacts on lateral excursions of the mandible in patients with TMD. A total of 122 temporomandibular joints (TMJs) of 61 patients with TMD were evaluated using magnetic resonance imaging (MRI) and occlusal analyses were made clinically. Non-working-side contacts were found to be statistically significant in TMJ anterior disc displacement. No significant statistical correlation was found between the severity of anterior disc displacement and non-working-side contacts in both canine guidance and group function occlusions. There was no correlation between non-working-side contacts and condyle positions in both occlusion types in the present study. It was concluded that non-working-side contacts had some effect on disc position in TMD, however the presence of these contacts in both canine guidance and group function occlusions did not correlate with anterior disc displacement in TMD statistically. Therefore, non-working-side contacts are not to be regarded as the prime cause of anterior disc displacement.

Expression of matrix metalloproteinases and their specific inhibitors in normal and different human thyroid tumor cell lines.

In the present study we investigated, by means of zymography and reverse transcription-polymerase chain reaction (RT-PCR), the expression of different matrix metalloproteinases (MMPs) and of the specific tissue inhibitor of metalloproteinases [TIMPs] in human cell lines derived from normal thyrocytes (HTU5), follicular adenoma (HTU42), and follicular (FTC-133), papillary (B-CPAP), and anaplastic (CAL-62, 8305C) thyroid carcinomas. We demonstrated that normal thyrocytes constitutively express MMP-1, MMP-2, MMP-10, MMP-14, and TIMP-1, TIMP-2, TIMP-3, and TIMP-4, and this pattern of expression is profoundly modified in all thyroid tumor-derived cell lines. Analysis of the gelatinolytic activity in the different cell supernatants showed that the expressions of MMP-2 and MMP-9 are, respectively, increased or induced in all the neoplastic cell lines, except in CAL-62. Caseinolytic activity was found only in the supernatants of the 8305C and B-CPAP cells. Using RTPCR analysis we detected an increased expression of MMP-1 in cell lines derived from papillary and from one (8305C) of the two anaplastic carcinomas. MMP-13 mRNA was expressed only in the 8305C, FTC-133, and BCPAP cells. Among stromelysins, MMP-3 mRNA could not be detected in any cell line, while MMP-10 mRNA was expressed in all of them, although at variable levels. MMP-11 mRNA was absent in normal and follicular adenoma derived thyrocytes and induced in all carcinoma cell types. The expression of MMP-14 (MT1-MMP) mRNA was found significantly increased in all thyroid tumor cell lines with respect to HTU5 and HTU42 cells. The expression of TIMP-1 and TIMP-2 mRNAs was maintained in all cell lines tested, while that of TIMP-3 was lost in both anaplastic carcinoma cell lines and that of TIMP-4 was absent in the CAL-62. In conclusion, our data demonstrated a differential expression of MMPs and TIMPs in different thyroid tumor cell types with respect to normal thyrocytes. In particular, the induction of MMP-11 in all thyroid-derived carcinoma cell lines studied and of MMP-13 in all but one may represent, if confirmed in other thyroid tumor-derived cell lines and in thyroid tumor tissues, a new marker of thyrocyte transformation.

Clinical correlation of MRI findings of internal derangements of the temporomandibular joints.

We studied 131 temporomandibular joints (TMJs) in 73 patients (56 women, 17 men) with internal derangement using magnetic resonance imaging (MRI) in addition to clinical examinations. The type of TMJ sounds correlated significantly with the degree of disc displacement. Rounded and folded disc deformities caused crepitus, which was a sign of the advanced stage of anterior disc displacement without reduction. Tenderness on palpation of the lateral pterygoid muscle was found in anterior disc displacements with or without reduction. The more deformed the TMJ disc that was shown on MRI the more substantial the clinical signs and symptoms. As the MRI results correlated well with the clinical findings we concluded that expensive diagnostic methods such as MRI should be used for surgical planning and in difficult cases to diagnose pathological conditions of the TMJ.

Metastatic breast carcinoma mimicking periodontal disease on radiographs.

BACKGROUND: Tumors can metastasize to the jaws, oral soft tissues, or salivary glands. Metastasis from distant organs and tissues to the jaws or oral cavity is considered rare. RESULTS: The mandible is the most common site of metastasis of the oral and maxillofacial region. Radiographically, there is usually an area of radiolucency with hazy outline. Such lesions are manifested as radiopaque or sclerotic areas. CONCLUSIONS: Radiographic view of a tumor in the present case mimicked a periodontal lesion with an osteolytic area around the roots.

The evaluation of temporomandibular joint disc position in TMJ disorders using MRI.

The purpose of this study was to correlate disc position and the type of disc displacement, intra-capsular effusion and degenerative changes of the condyle as demonstrated in MRI studies. In this study, 126 temporomandibular joints (TMJs) of 63 patients with TMJ disorders were investigated using clinical examination and MRI. One hundred and twelve TMJs were found to have internal derangement as disc displacement. The angle between the posterior margin of the disc and the vertical line drawn through the centre of the condyle was measured on MRI for each TMJ. The positions of the discs were normal, 0 degrees-10 degrees, in 11.11%; slightly displaced, 11 degrees-30 degrees, in 37.30%; mildly displaced 31 degrees-50 degrees, in 15.08%; moderately displaced, 51 degrees-80 degrees, in 7.14% of the TMJs with anterior displacement with reduction (ADDR). The disc position was severely displaced anteriorly, as over 80 degrees, in all TMJs with anterior disc displacement without reduction (ADD), constituting 27.78% of all cases. We found that the smaller the degree of disc displacement the milder the internal derangement and that the intra-capsular effusion was more frequently associated with TMJ with ADDR. The degenerative condylar changes were more severe with an increased degree of anterior disc displacement.

Magnetic resonance imaging evaluation of temporomandibular joint disc deformities in relation to type of disc displacement.

PURPOSE: This study was undertaken to assess the relationship between the temporomandibular joint (TMJ) disc deformity and the type of internal derangement. PATIENTS AND METHODS: One hundred thirty-three TMJs of 72 patients (53 female and 19 male) with intracapsular dysfunction were studied using clinical and magnetic resonance imaging examinations. RESULTS: Of the 133 TMJ discs, 41.35% had no deformity, whereas 18% of the discs were folded, 19.55% were lengthened, 9.77% were round, 7.51% were biconvex, and 3.75% had thick posterior bands. The frequency of disc deformity was greater with anterior disc displacement without reduction than in cases of anterior disc displacement with reduction (P <.001). Folded and round discs were most common in cases with TMJ anterior disc displacement without reduction (P <.0001). An increase in length was seen in 56.75% of the cases with anterior disc displacement with reduction, whereas 100% of nonreducing discs were mainly folded or rounded. Crepitation was correlated with folded and round disc deformities, whereas lengthening was the feature of reducing discs associated with early and intermediate clicking. CONCLUSIONS: The results show that the degenerative changes in the TMJ disc are influenced by the degree and the type of disc displacement. The more advanced the internal derangement, the more deteriorated the disc configuration.

An unusual form of Actinomycosis of the mandible with a resultant gross sequester in a 4-year-old child: a case report.

Mandibular osteomyelitis due to Actinomyces group is considered rare in the pediatric population. The initial complaint of the 4-year-old child described here was increased swelling of his cheek and pain. The patient was managed successfully by surgical treatment with antibiotic therapy.

Computerized 3-dimensional study of the embryologic development of the human masticatory muscles and temporomandibular joint.

PURPOSE: In this study, the development of human embryonic temporomandibular joint (TMJ) and masticatory muscles were investigated by using computed 3-dimensional reconstructions. MATERIALS AND METHODS: Sixteen human embryos and fetuses, ranging from 6.5 to 107 mm crown-rump length, were examined. RESULTS: At 10 weeks, a band of mesenchyme extending from the attachment of the lateral pterygoid muscle to the condylar process was observed to pass through the medial side of the condylar process to attach to the malleus. The temporal, masseter, and pterygoid muscles develop from the so called "temporal muscle" primordium, and the temporal muscle was in continuity with the masseter muscle until 14 weeks of fetal life. CONCLUSIONS: The study shows that the muscles of mastication arise from a single primordium. It also confirms the presence of a ligamentous attachment between the lateral pterygoid muscle and the malleus.

Detection of Epstein-Barr virus early replicative phase using monoclonal antibody BZ-1 in oral hairy leukoplakia and other hyperkeratotic oral mucosal lesions: a retrospective study.

The early replicative phase of Epstein-Barr virus (EBV) was detected by immunohistochemistry, in addition to routine histology with hematoxylin eosin staining, in formalin fixed, paraffin-embedded archive specimens of 97 hyperkeratotic lesions including oral hairy leukoplakia (HL) in order to assess whether EBV is specific to HL, or if it occurs in other hyperkeratotic lesions of the oral mucosa. Monoclonal antibody (MAb) BZ-1 directed against the BZLF-1 gene product of EBV was used for immunostaining by the avidin-biotin peroxidase technique. The reaction was visualized with DAB/H2O2 solution and counterstained with PAS stain to detect any coexisting of hyphae of Candida. Eight lesions were reactive with BZ-1, confirming a diagnosis of HL, although the total number of lesions with koilocytoid features was 33. Seventy percent of the patients with confirmed HL lesions were HIV-seropositive, and 50% of the HL lesions were associated with Candida hyphae. One third of the lesions with koilocytoid features were associated with hyphae of Candida. Only one renal transplant patient had HL, confirmed by a positive BZ-1 reaction, although 60% of the hyperkeratotic lesions showed koilocytoid features in a subgroup of 15 patients with renal transplants.

The morphogenesis of the human discomalleolar and sphenomandibular ligaments.

The morphogenesis of the discomalleolar ligament and its relationship with the sphenomandibular ligament were studied in human embryos and fetuses, on histological grounds. Total number of 18 embryos and fetuses, ranging from 6.5 to 230 mm (5-25 weeks of fertilization age) were examined. The discomalleolar ligament emerged from the posterior part of the temporomandibular joint capsule and disc, passing through the squamotympanic fissure, joined the malleus. The superior fibres of the ligament inserted on the anterior process of the malleus and on the bony wall of the squamotympanic fissure. The inferior fibres of the discomalleolar ligament encircles the anterior malleolar ligament, the remnant of Meckel's cartilage, and chorda tympani, and inserted on the tympanic wall of the temporal bone. Within the tympanic cavity, the discomalleolar ligament and the anterior malleolar ligament, a continuation of the sphenomandibular ligament, formed a horizontal 'V' shape at the attachment site on the ventral surface of the malleus. The study shows that the discomalleolar ligament is an embryological continuation of the sheath of the lateral pterygoid muscle. The sphenomandibular ligament derives from Meckel's cartilage.