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.

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.

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.

The development of the human lateral pterygoid muscle and the temporomandibular joint and related structures: a three-dimensional approach.

The development of the human fetal temporomandibular joint and surrounding structures was investigated in 11 specimens on the basis of histologic examination and three-dimensional reconstructions. Until the 10th week, there were no signs of the disc, joint spaces and capsule formation of the temporomandibular joint (TMJ). Apart from Meckel's cartilage, all the temporomandibular joint and related structures attained their adult shape at 14 weeks. Throughout the embryologic and fetal development, the relative positions of the branches of the mandibular nerve remained unchanged. From 11-12 weeks onwards, the lateral pterygoid muscle became a complex structure which was segmented by aponeuroses dividing the muscle into three main parts: superior, infero-medial and infero-anterior parts. The superior segment was attached to the TMJ disc superiorly and medially. The infero-medial segment was inserted onto the antero-medial aspect of the TMJ condyle and disc. The infero-anterior portion was attached to the anterior aspect of the condyle.

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.

Audiological evaluation of the aural symptoms in temporomandibular joint dysfunction.

In this study, audiological assessments of the 57 patients with temporomandibular joint dysfunction and 57 controls were made. The analyses of audiograms, tympanograms and Eustachian tube functions showed no significant differences statistically. A slight increase in compliance peak in 48 female patients suggests that the sound conducting structures of the middle ear could be influenced by the reflex spasm of the tensor tympani muscle to a minor degree. This change does not seem to cause a major dysfunction either in the middle ear or in the Eustachian tube.

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.

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.

Multiple bilateral dens in dente involving all the premolars. Case report.

Dens in dente, also known as dens invaginatus, dilated composite odontoma or deep foramen caecum, is a developmental malformation which usually affects maxillary incisor teeth, particularly lateral incisors. It may occur, however, in teeth anywhere within the jaws but other locations are comparatively rare. It can occur within both the crown and the root, although crown invaginations are more common. In this paper a case of multiple bilateral dens in dente involving maxillary and mandibular premolars is presented.

Mandibular central giant cell granuloma associated with sclerosing osteomyelitis of Garrè (periostitis ossificans). Case report.

Garrè's sclerosing osteomyelitis or periostitis ossificans with a radiographic 'onion skin' appearance is a separate clinical entity. The new bone formation underneath the periosteum is a response of periosteum to stimulation by low grade infection. This may occur in a variety of other developmental, metabolic, inflammatory and neoplastic diseases of bone. A case of mandibular giant cell granuloma of a central type associated with Garrè's sclerosing osteomyelitis is presented and the literature is reviewed.

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.

CT display of multiple dentigerous cysts of the mandible: a case report.

Computerized tomographic (CT) display of a case with multiple dentigerous cysts in the mandible is presented and benefits of the CT in such cases are discussed. CT images provides 3 dimensional accurate details of the cystic lesions without any distortion and superposition. It shows the exact size, location and possible origin of the cysts as well as the extent of the bone destruction. It is considered that CT could be used as a guide in presurgical evaluation of the complex cystic lesions of the jaws.

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.

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.