Fracture toughness of nanohybrid and hybrid composites stored wet and dry up to 60 days

Patients' demand for tooth-colored restoratives in the posterior region is increasing. Clinicians use universal nanohybrid resin composites for both anterior and posterior regions. There are few published reports comparing fracture toughness of nonohybrids and that of hybrid composite stored wet and dry

Objectives: To investigate the fracture toughness of three nanohybrids compared to that of a hybrid resin composite stored dry or wet up to 60 days, using four-point bending test

Materials and Methods: Four resin composites were used: three nanohybrids; Filtek Supreme [3M], Ice [SDI], TPH3 [Dentsply] and one hybrid Filtek P60 [3M]. For each material, 40 rectangular notched beam specimens were prepared with dimensions of 30 mm × 5mm × 2mm. The specimens were randomly divided into 4 groups [n = 10] and stored at 37[degree sign]C either in distilled water or dry for 1 and 60 days. The specimens were placed on the four-point test jig and subjected to force [N] using universal testing machine loaded at a crosshead speed of 0.5mm/min and maximum load at specimen failure was recorded and K[Ic] was calculated

Results: Three-way ANOVA showed a significant interaction between all the factors [all p < .0001]. Except for TPH3, all tested materials showed significantly higher K[Ic] when stored dry than stored wet [p < 0.05]. After 1 day of dry storage, Ice showed the highest K[Ic] [2.04 +/- 0.32] followed by Filtek P60 and the lowest was for Filtek Supreme [1.39 +/- 0.13]. The effect of time on fracture toughness was material dependent

Conclusions: Wet storage adversely affected the fracture toughness of almost all materials. Keeping the restoration dry in the mouth may increase their fracture toughness. Therefore, using a coating agent on the surface of restoration may protect them from early water uptake and increase their strength during a time period

Evaluation of compressive strength and sorption/solubility of four luting cements

Statement of Problem: Compressive strength [CS] and sorption/solubility of the luting cements are two associated factors. Searching a correlation between sorption/solubility and compressive strength of various luting cements is required

Objectives: To measure the water sorption/solubility, and compressive strength of three resin-based and one conventional glass ionomer [CGI] luting cement after 1 and 24 h of immersion in distilled water and to determine if there is any correlation between those properties found

Materials and Methods: Four luting cements were investigated. For each material, 10 disc shaped specimens were prepared for measuring the sorption/solubility. The specimens were cured according to the manufacturer's instructions, and the sorption/solubility were measured in accordance with the ISO 4049's. For testing the compression strength, for each material 16 cylindrical specimens were prepared by insertion of cements into a stainless steel split mould. The specimens were cured, divided into groups of 8, and then stored in distilled water at [37 +/- 1][degree]C for 1 and 24 h. The test was performed using the universal testing machine, the maximum load was recorded and CS was calculated. The data were analysed using SPSS software version 18. One-way ANOVA, post-hoc Tukey's test and Pearson's correlation coefficient were performed

Results: G-CEM had the highest mean CS [153.60 +/- 25.15] and CGI luting had the lowest CS [21.36 +/- 5.37] [p <0.001]. After 24 h, mean CS values showed an increase for almost all materials except for RelyXTM U200 which showed a slight reduction. However, no statistically significant difference was founded [all p > 0.05]. The lowest mean sorption/solubility value was for RelyXTM U200 and Panavia F, and the highest for CGI luting [all p < 0.001]

Conclusions: The compressive strength of all cements did not necessarily increase after 24 h and varied depending on the materials. There was a strong reverse correlation between sorption and CS values after both 1 and 24 h immersion. It may be practical for clinician to use those cements with the less sorption / solubility and more stable compression strength over time

effect of different polishing methods and storage media on discoloration of resin composites

Statement of Problem: Accumulation of plaque and staining due to a rough surface, and penetration of colourant agents from food and beverages in to the resin composite results in an incomplete polymerization. There is a little information on the effect of finishing and polishing techniques on the discoloration of nanohybrid and microhybrid composites when exposed to staining solutions

Objectives: To determine the degree of surface staining of nanohybrid and microhybrid composites after polishing and immersion in distilled water and two commonly used staining solutions

Materials and Methods: A nanohybrid [Ice; SDI] and microhybrid [Gradis direct; GC] composites were used. Disc-shaped specimens were prepared and treated with either a matrix finish or polished using Sof-Lex discs [3M/ESPE] and Enhance point [Dentsply]. After 24 h immersion in distilled water at 37[degree sign]C the specimens were polished and colour coefficients [CIE L[asterisk] a[asterisk] b[asterisk]] was measured by a spectrophotometer. All specimens were immersed in 37[degree sign]C distilled water in an incubator for 7 days and colour coefficients were measured again. The colour change [[DELTA]E] was calculated using the following formula: [Delta]E = [[[Delta]a][2]+[[Delta]b][2]+[[Delta]L][2]] [1/2]. The data were analyzed using three-way ANOVA, one-way ANOVA/Tukey HSD and Student's t-test

Results: There was a significant interaction between resin composites, polishing systems and staining solutions [p < 0. 05]. ANOVA and Tukey's tests showed that Ice had a significantly lesser colour change than Gradia direct and matrix finish revealed the smoothest surface followed by Sof-Lex discs and Enhance point. Distilled water and cola caused no perceptible colour change [[Delta]E < 3.3]. The effect of surface polish on staining was statistically significant [p < 0 .05]

Conclusions: Sof-Lex discs in comparison to Enhance point stimulated greater staining resistance for both composites. The nanohybrid exhibited less colour change than microhybrid composite. Coffee was the only storage media that induced a perceptible colour change [[Delta]E > 3.3] compared to cola and distilled water

influence of surface polish and beverages on the roughness of nanohybrid and microhybri resin composite

Statement of the Problem: Surface roughness is a key factor in the aesthetics of restorative dentistry as it can determine the clinical quality and success of restorative materials. The chemical process of dissolution in the presence of mechanical forces can accelerate the surface roughness of tooth-coloured restorative materials

Objectives: To determine the degree of surface roughness of a microhybrid and a nanohybrid resin composite after polishing and immersion in various solutions

Materials and Methods: Two resin composites were used: a microhybrid [Gradia direct, GC], and a nanohybrid [Ice, SDI]. A total of 54 disc-shaped specimens were prepared for each composite and immersed in distilled water incubated at 37[degree]C for 24 hours. After 24 h, the baseline measurement for surface roughness [Ra] was performed and the specimens were divided into 3 groups of 18 and tested with unpolished or after polishing with Sof-Lex disc and Enhance point systems. Specimens in each group were subdivided into 3 subgroups [n = 6] and immersed in 3 solutions [distilled water, coffee, and cola] for 7 days incubated at 37[degree]C. After 7 days, the specimens were rinsed with tap water for 10 seconds, dried with paper towel and Ra was measured again. Two randomly selected specimens of each group were sputter coated with gold and examined using a Field-Emission Scanning Electron Microscope [SEM]

Results: Gradia direct showed a greater R[a] than ice in all solutions for all polishing systems [p < 0.001]. Specimens polished with Enhance point revealed a significantly greater roughness than Sof-Lex discs and both showed greater R[a] than unpolished specimens. Specimens immersed in coffee exhibited significantly greater surface roughness than that of distilled water [p < 0.05] and cola [p < 0.001]

Conclusions: Nano-hybrid composite showed a significantly smoother surface than microhybrid. Coffee exhibited the highest R[a] compared to distilled water and cola. Enhance point revealed significantly greater R[a] than Sof-Lex discs and unpolished group

Fracture toughness of resin composites under different modes and media: review of articles

This article aims to review various modes of fracture toughness of resin composites. Also, this study intends to review the papers on the fracture mode, namely "fractography", under scanning electron microscopy finding fracture initiation site, and the effect of filler content on the fracture toughness of resin composites. It will also review the effect of aging on the fracture toughness of resin composites in different media, mainly distilled water, and acidic environment. In the review performed on fracture toughness of resin composites we used "fracture toughness [KIc]", aging AND fracture toughness, AND fractography" of resin composites as the search strategy. The outcome of the review revealed that most of the studies investigated fracture toughness of resin composites under Mode I and less under mode II. However, some others looked at the fracture toughness of dental resin composites under mixed-mode loading conditions. It was also found that fracture toughness studies performed on the same types of resin composites resulted in different values of KIc. The differences were related to the method of performance that requires different specimen geometries

Effect of caries removal methods on the shear bond strength of resin and glass ionomeradhesives to primary dentin

Statement of Problem: There is no enough published data about the shear bond strength of resin modified glass ionomer adhesives on caries-affected primary tooth dentin excavated using minimally invasive systems

Objective: To evaluate the shear bond strength of 2 different adhesives [one resin modified glass ionomer and one resin] using two caries removal techniques on healthy and caries-affected primary dentin

Materials and Methods: Two caries removal methods including mechanical [handpiece] and chemomechanical [Carisolv] techniques and two types of adhesives including one resin adhesive [Clearfil SE Bond; CSEB, Kuraray] and one resin-modified glass ionomer adhesive [Riva Bond LC; RBLC, SDI] were used in this study. Ten extracted healthy primary teeth were used for the control group. The teeth were sectioned bucco-lingually and mesio-distally in order to obtain four specimens from each tooth. Thirty suitable specimens were selected as the "control" and randomly divided into two groups of "sound dentin" based on the type of the adhesive used. Sixty extracted caries affected teeth were used for the carious group; sectioned as mentioned above and sixty suitable specimens were selected as the "treatment". Then the specimens were arbitrarily divided into four groups based on caries removal techniques and the type of adhesive used [n = 15]. After bonding with either CSEB or RBLC, the specimens were restored with a resin composite by means of PVC tubes and subjected to the shear bond strength test. The data was analyzed using ANOVA and Tukey's test

Results: The specimens in Carisolv group bonded with CSEB [11.68 +/- 3.1] showed a statistically significant higher mean bond strength followed by those in handpiece group bonded with CSEB [9.4 +/- 2.7], which exhibited higher mean values than those groups with RBLC [p < 0.05]. Shear bond strength values for Clearfil SE Bond was not significantly higher than Riva Bond LC when used in sound dentin

Conclusion: The lowest shear bond strengths for both adhesives were observed on caries-free dentin

Bioactive glasses in Dentistry: a review

Bioactive glasses are silicate-based and can form a strong chemical bond with the tissues. These biomaterials are highly biocompatible and can form a hydroxyapatite layer when implanted in the body or soaked in the simulated body fluid. Due to several disadvantages, conventional glass processing method including melting of glass components, is replaced by sol-gel method with a large number of benefits such as low processing temperature, higher purity and homogeneity and therefore better control of bioactivity. Bioactive glasses have a wide range of applications, particularly in dentistry. These glasses can be used as particulates or monolithic shapes and porous or dense constructs in different applications such as remineralization or hypersensitivity treatment. Some properties of bioactive glasses such as antibacterial properties can be promoted by adding different elements into the glass. Bioactive glasses can also be used to modify different biocompatible materials that need to be bioactive. This study reviews the significant developments of bioactive glasses in clinical application, especially dentistry. Furthermore, we will discuss the field of bioactive glasses from beginning to the current developments, which includes processing methods, applications, and properties of these glasses

Fracture toughness evaluation of hybrid and nano-hybrid resin composites after ageing under acidic environment

Tooth-coloured restorative materials are brittle with the major shortcomings of sensitivity to flaws and defects. Although various mechanical properties of resin composites have been studied, no fracture toughness test data for nano-hybrid composites under acidic condition for a long period of time has been published.To compare the fracture toughness [K[Ic]] of two types of resin composites under tensile loading and to assess the effect of distilled water and lactic acid on the resistance of the restoratives to fracture after three months of immersion.Four resin composites were used: three nano-hybrids [EsteliteSigma Quick [Kuraray], Luna [SDI], Paradigm [3M/ESPE]] and one hybrid, Rok [SDI]. The specimens were prepared using a custom-made polytetrafluorethylene split mould, stored in distilled water [pH 6.8] or 0.01mol/L lactic acid [pH 4] and conditioned at 37°C for 24 hours, 1 or 3 months. They were loaded under tensile stress using a universal testing machine; the maximum load [N] to the specimen failure was recorded and the fracture toughness [K[Ic]] was calculated. Data were analysed by ANOVA and Tukey's test using SPSS, version 18.The results of two-way ANOVA did not show a significant combined effect of material, time, and storage medium on fracture toughness [p= 0.056]. However, there was a strong interaction between materials and time [p=0.001] when the storage medium were ignored. After 24 h of immersion in distilled water, Paradigm revealed the highest [K[Ic]] values followed by Rok, Luna and Estelite. Immersion in either distilled water or lactic acid significantly decreased the fracture toughness of almost all materials as time interval increased. Paradigm showed the highest fracture toughness followed by Rok, Luna and Estelite respectively. As time increased, [K[Ic]] significantly decreased for almost all resin composites except for Luna which showed a slight decrease after one month of immersion in distilled water

Modification of a soft drink by adding calcium carbonate nanoparticles to prevent tooth erosion

One of the factors in dental erosion is consumption of acidic soft drinks. Although the effects of various additives to acidic soft drinks for the prevention of tooth erosion have been assessed, little data have been published on the possibility of preventing the erosion through soft drinks containing calcium-carbonate nanoparticles. To examine the erosive factors of 7up soft drink and to determine the possibilities of decreasing or preventing the erosion phenomenon of the soft drink containing calcium-carbonate nanoparticles. 7up soft drink was assigned as control and a set of solutions containing 0.04, 0.05, and 0.06 vol % of the nano-particles were assigned as the experimental solutions. The pH, titratable acidity [TA], calcium and phosphorus concentrations and degree of saturation with respect to enamel hydroxyapatite [DS[En]] were calculated. These parameters refer to assessment of erosive potential of the soft drinks. The erosion potential was evaluated based on the micro-hardness and the structural changes of the tooth surface using scanning electron microscopy [SEM].Data were analyzed using Kruskal-Wallis H test,andBonferroni-adjusted Mann-Whitney U test. An increase in the nano-additive content of the solutions increased pH and DS[En] however, it decreased the TA [P < 0.05]. There was a significant difference between the micro hardness in the control and experimental groups [p<0.001]. SEM imagesrevealed less surface erosion of the specimens stored in the higher nano-additive concentrations.The modified drink containing 0.06% nano-additive revealed the highest hardness with no evidence of tooth erosion. Adding calcium carbonate nanoparticles to soft drinks can be considered as a novel method to reduce or prevent tooth erosion

Effect of a home bleaching agent on the fracture toughness of resin composites, using short rod design

Statement of Problem: Resin composites are brittle materials and their major shortcomings are manifested in their sensitivity to flaws and defects. Although various mechanical properties of resin composites have been described, few studies are available on assessing the effect of bleaching agents on resin composites using the short rod design

Purpose: To place various resin composites into distilled water at 37°C for 21 days and determine the effect of immersion time in distilled water, with and without exposure to 10% carbamide peroxide by employing short rod design fracture toughness test

Materials and Method: Specimens were prepared from three resin composites; Rok [SDI], Esthet [Dentsply], and Estelite [Tokuyama]. For each material, a total of 24 disc-shaped specimens were prepared using a custom-made mould. Specimens were randomly divided into 3 groups of 8 and conditioned in 37°C distilled water for either 24 hours, or 21 days. 21 day specimens were tested both with and without applying bleaching agent; Polanight [SDI]. Study group specimens were bleached for 21 days, 2 hours a day. The specimens were loaded using a universal testing machine with a crosshead speed of 0.5 mm per minute. The maximum load at specimen failure was recorded and the K[Ic] [MPa. M [0.5]] was calculated

Results: Statistical analysis using two-way ANOVA showed a significant relationship between material and time [p< 0.05].Tukey's test showed that after 24 h of immersion in distilled water, Rok revealed the highest K[Ic] followed by Esthet and Estelite. The bleaching agent significantly improved the fracture toughness values of Esthet while it decreased that of Estelite

Conclusion: The fracture toughness of the resin composites was affected by the bleaching agent and distilled water. In comparison with Rok and Estelite, fracture toughness of Esthet was increased due to aging and application of bleaching agent

Film thickness and flow properties of resin-based cements at different temperatures

Statement of Problem: For a luting agent to allow complete seating of prosthetic restorations, it must obtain an appropriate flow rate maintaining a minimum film thickness

The performance of recently introduced luting agents in this regard has not been evaluated

Purpose: To measure and compare the film thickness and flow properties of seven resincontaining luting cements at different temperatures [37°C, 25°C and10°C]

Material and Methods: Specimens were prepared from five resin luting cements; seT [SDI], Panavia F [Kuraray], Varioloink II [Ivoclar], Maxcem [Kerr], Nexus2 [Kerr] and two resin-modified glass-ionomer luting cements [RM-GICs]; GC Fuji Plus [GC Corporation], and RelyX Luting 2 [3 M/ESPE]. The film thickness and flow rate of each cement [n=15] was determined using the test described in ISO at three different temperatures

Results: There was a linear correlation between film thickness and flow rate for most of the materials. Cooling increased fluidity of almost all materials while the effect of temperature on film thickness was material dependent. At 37°C, all products revealed a film thickness of less than 25µm except for GC Fuji Plus. At 25°C, all cements produced a film thickness of less than 27 µm except for seT. At 10°C, apart from seT and Rely X Luting 2, the remaining cements showed a film thickness smaller than 20 microm

Conclusion: Cooling increased fluidity of almost all materials, however. the film thickness did not exceed 35 µm in either condition, in spite of the lowest film thickness being demonstrated at the lowest temperature

[Effects of the lower leg tapping on H reflexes recruitment curve parameters: a comparison of soleus and lateral gastrocnemius muscles motor neurons]

The application of tapping has been widely used by physiotherapists for many years as a useful rehabilitation program in the treatment of a wide variety of neuron musculoskeletal disorders. Therefore the aim of this study was to answer whether Tapping has the same effects on fast jerking muscles motor neurons as it affects slow muscle or not? In this semi-experimental study, Fifteen non-athletic healthy volunteers with the age of 27.7 +/- 3.4 ?years old in the way of available sampling were assessed. After cutting and preparing, the Y-strip Kinesiotape was applied on insertion of Achill Tendon toward medial and lateral head of Gastrocnemious muscles. The H-Reflex was used for assessment of motor neurons recruitment curve of soleus and lateral gastrocnemious muscles. Percutaneously 40 electrically pulses with duration of 1 millisecond and 3 stimulations per each stimulus intensity were induced on Tibial nerves and H-Reflex recruitment curve were recorded in 4 phases. In order to compare the parameters between two muscles the ANOVA repeated measurement was used. The required intensity to record the last H-Reflex in recruitment curve was significantly decreased in lateral Gastrocnemious compare with Soleus, 5 minutes after tapping [P=0.01] and 15 minutes after stopping the tap [P=0.03]. There was a significant difference in the average changes in other variables. But There was a significant difference in all other variables in lateral gastrocnemious compare with soleus muscle [P<0.05]. Tapping has more facilitative effects on lateral Gasterosoleus muscle specially type I motoneurons and to some lesser extent in soleus motoneurons. Therefore it seems that Tapping can be more used to facilitate fast muscles

Isolation of Acanthamoeba Spp. from drinking waters in several hospitals of Iran

Acanthamoeba is an opportunistic amphizoic protozoan found in different water sources including swimming pool as well as in sewage. The aim of this study was to investigate the prevalence of Acanthamoeba in tap-water samples in Iran. In this descriptive cross-sectional study, 94 samples of cold and warm tap-water were collected from different wards of hospitals in 13 cities of Iran in 2007-2008. Free residual chlorine, pH, and temperature of samples were measured. After filtration through multipore nylon membrane, samples were cultured on non-nutrient agar. Then we investigated existence of Acanthamoeba by reverse contrast phase microscope. Acanthamoeba was found in 45 samples [48%]. Thirty-four and 11 positive samples were collected from cold and warm tap water, respectively. The samples belonged to the category of 20-30 °C temperature with 0-2 ppm free residual chlorine and pH 6-7.4 showed the most coincidence to the positive cases. The greatest proportion of positive samples was obtained from Mashhad hospitals, while all samples collected from Arak and Semnan hospitals were negative. Considering the results of this study and the pathogenic role of this protozoan on patients with immunodeficiency, as well as capability of this microorganism in carrying other pathogens such as Legionella, further studies are needed. What is more important, potable water in hospitals should follow the procedure of treatment and sanitation, in order to prevent the relevant nosocomial infections

[Evaluation of bone marrow involvement in surgically resected patients with esophageal cancer]

Bone marrow samples obtained during rib resections in esophageal cancer patients evaluated by immunohistochemical and quantitative polymerase chain reaction techniques revealed disseminated tumor cells in up to 90% samples, but the clinical relevance of these findings is unclear. Evaluation of bone marrow involvement in these patients and its correlation with clinicopathological finding of tumor. 43 patients with esophageal cancer who referred to Omid and Ghaem hospitals from April 2008-2009 were selected to transthorasic surgery[without neoadjuvant treatment].Bone marrow samples from rib were evaluated by Hematoxylin-Eosin staining for tumoral involvement and cytokeratin immunohistochemistry to determine micrometastatic cells. The results were compared with primary tumor histopathologial characteristics; T stage, N stage, tumoral length and personal characteristics; age and sex. Patients mean age was 60.9 [51-70 years], the ratio of male to female was 2.9. 38 cases [88.4%] had squamous cell carcinoma and 5 [11.6%] adenocarsinoma. In 9 cases [20.9%] Hematoxylin-Eosin staining and 13 cases [30.2%] immunohistochemistry results were positive. There was no correlation between pathologic type and T stage with Hematoxylin-Eosin and cytokeratin results. [p=0.277, p=0.153] and [p=0.221, p=0.097]. There was a significant relation between bone marrow dissemination and mediastinal involvement and tumoral grade [p=0.008, p=0.001] and [p=0.002, p=0.001]. According to our study, there is a correlation between grade and N stage and bone marrow involvement in esophageal cancer patients and there is no statistically correlation with other clinicopathologial characteristic there is a low bone marrow involvement in our region patients, overally

[Photodynamic therapy for vasoproliferative tumors and capillary hemangiomas of the retina]

To evaluate the results of Verteporfin photodynamic therapy [PDT] in vasoproliferative tumors [VPT] of the retina and retinal capillary hemangiomas [RCH]. In a retrospective case series, 6 tumors in 5 eyes with VPT, and 3 RCH in 3 eyes underwent PDT which was performed using intravenous Verteporfin. Eyes were evaluated for tumor regression, final bestcorrected visual acuity [BCVA], and final retinal status. Patients were followed for a mean period of 7.1 +/- 3.9 months. Mean number of PDT sessions for each tumor was 1.33 [range 1-2]. Overall, mean BCVA improved from 1.7 +/- 1.06 to 0.88 +/- 0.8 logMAR [P=0.017]. Tumor thickness decreased from 3.53 +/- 0.83 to 1.73 +/- 0.73 mm [P<0.001]. Subgroup analysis revealed improvement in BCVA and tumor thickness in the VPT group [P=0.04]. However, in the RCH group, there was no statistically significant improvement in BCVA [P=0.43] despite significant reduction in tumor thickness [P=0.024]. A favorable outcome characterized by improved or unchanged visual acuity was achieved and the tumor regressed in all eyes. Subretinal fluid was absorbed in all eyes except for one eye with preoperative proliferative vitreoretinopathy. Vasoproliferative tumors and retinal capillary hemangiomas can be treated effectively by Verteporfin PDT and a favorable outcome can be expected

role of VATS [Video assisted thoracic surgery] in the evaluation of patients with undiagnosed exudative pleural effusion

Video assisted thoracic surgery [VATS] is a new minimal invasive diagnostic and therapeutic method in lung diseases that provides a perfect view of pleura and pericardium to perform a diagnostic biopsy from the pathologic site. This study aimed to evaluate the diagnostic value of VATS in pleural effusion with an unknown cause. In this descriptive study, carried out from 1999 to 2007 in thoracic surgery department of Ghaem Hospital, sixty five patients with undiagnosed exudative pleural effusion underwent VATS for tissue diagnosis, and six months follow up was performed. Age and sex, pathology and diagnostic accuracy rate collected by questionnaire and processed using the SPSS software by descriptive statistics and frequency distribution table. Among 65 patients, 33.8% were female and 66.2% were male. Mean age was 58.90 +/- 14.57 years. The most common clinical symptom was dyspnea which was seen in 87.7%. Pleural effusion was clear yellow in 55.4% and bloody in 44.6%. Malignant cytology was reported only in one case [1.5%]. Transthoracic needle biopsy showed pleuritis in 86.2%, fibrosis in 10.8% and it was suspicious in 3.1%. VATS was diagnostic in 95.4% and exact diagnosis wasn't obtained only in 3 cases [4.6%]. Open biopsy was performed in these cases that indicated Mesotelioma in two cases, another case with the history of CABG was treated after 6 months of follow up. The most common diagnosis was metastatic carcinoma, which observed in 37 cases [56.9%]. VATS diagnostic accuracy rate in this study was 95.4%. No complication was seen in 98.5% and only one case had bleeding [1.5%]. Mortality rate, because of VATS complications, was not seen. According to the safety, high sensitivity and specificity of VATS, it is suggested as a good diagnostic method in pleural effusion with an unknown cause

Clinical results of thymectomy in myasthenia gravis patients

Myasthenia gravis is an autoimmune disorder affecting postsynaptic acetylcholine receptors of voluntary muscles. Since Blalock et al. first demonstrated the beneficial effect of thymectomy in 1939. The procedure has become increasingly accepted in the treatment of myasthenia gravis. we studied clinical results of thymectomy in myasthenia gravis cases during 12 years retrospectively and antegradly. Our variables included: patient's age, sex, and signs at the time of admission, disease onset to operation interval, postoperative complications, and duration of hospitalization, thymus histology and clinical response to thymectomy. Data were analyzed appropriate analysis. 16 women and 11 men with median age of 29.8 [ +/- 12.7] years were operated on by median sternotomy approach. Thymectomy was done during less than 1 year after disease onset in 44%, 1-3 years later in 42% and later than 3 years in 14%. Most had mild to moderate generalized myasthenia. Thymic hyperplasia was reported to be the most common pathologic finding. Clinical response to thymectomy was good [70.4%]. The best results were obtained in female less than 40 years old, with out thymoma, disease onset to operation interval less than 2 years and mild myasthenia. Because of its high beneficial rate thymectomy is an advantageous therapeutic option. The chance of benefit increases when the history of myasthenia gravis is short and the stage of the disease is early

[ role of ultrasonography guided transthoracic needle biopsy in diagnosis of peripheral pulmonary mass]

Transthoracic needle biopsy [TNB] is a well established method for obtaining pathologic diagnosis in the lung masses that is performed after a previous negative bronchoscopy. The goal of this study was evaluation of the safety and accuracy of ultrasonography guided TNB in diagnosis of peripheral lung masses. This descriptive study was done from 2005 to 2006 in Ghaem Hospital. 30 patients with peripheral lung mass, greater than 3[cm] in diameter and within 5[cm] from the chest wall, underwent ultrasonography guided TTNB. Data was gathered in a questionnaire and analyzed by descriptive statistics and frequency distribution tables. Male to female ratio was about 1:2, and mean age was 61.2 years. 60% lesions were located in the right side. Adequate biopsy specimens were obtained in all patients; but TNB was diagnostic in 86.6%, 13.3% patients underwent thoracotomy for definitive diagnosis. Pathological diagnoses were malignant in 83.3%, with SCC and ACC being the most common, and benign in 16.6%, the most common of which was tuberculosis. Complications were observed in 13.3%, including pneumothorax in 6.6%, and hemoptysis in 6.6%; mortality was not observed. According to this study, TNB with ultrasonography guide due to appropriate diagnostic accuracy and low complication rate with low cost and good availability is recommended for diagnosis of peripheral lung mass

[Report 9 cases of adenoid cystic carcinoma of trachea]

Primary malignant neoplasm of trachea are very rare and there is limited information about them. Adenoid cystic carcinoma is a slow-growing malignant tracheal tumor and the best method of treatment is surgical resection. This study was conducted for evaluation of patients with adenoid cystic carcinoma of trachea after treatment. In this descriptive study, all patients treated for adenoid cystic carcinoma between 1995 to 2006 in Mashad Ghaem hospital and Tehran Imam Khomeini hospital, were analyzed statistically. Of nine patients, female to male ratio was 2/1,the mean age of patients was [56.3] years, dyspena and stridor were the most common presenting symptoms [88.8%] and CT scan was the best diagnostic imaging method. The most common site of involvement was in lower third of trachea [44.4%]. [77.7%] of patients underwent surgical resection, hospital mortality after tracheal resection occurred in one patient due to complication [14.2%] aspiration pneumonia. During three years follow up just one patient [11.1%] had tumor recurrence and resection with post operative radiotherapy was performed in this cases overall three-year survival was 88.8%. Because of the nature of adenoid cystic carcinoma in trachea, surgical resection is the best method of treatment, but if surgical margin is positive, post operative radiotherapy will be necessary. In patients who are not candidates for resection, radiotherapy can be an effective alternative treatment

[Carcinoid tumor of trachea: a case report]

Carcinoid Tumor in trachea is rare, and in 25% are asymptomatic. Cough is the most common symptom and some times have similar symptoms such as chronic obstructive pulmonary disease. The best method of treatment is surgical resection and recurrency after resection is rare. In this study we report a 47 year's old man with chronic cough and dyspnea that treated with bronchodilator as COPD but without recovery. In evaluation with chest X. Ray, CT scan and bronchoscopy carcinoid tumor was diagnosed and surgical resection performed.There was no recurrency or complication in 5 years follow-up