DANESHVAR MEDICINE
Year:2006 | Volume:13 | Issue:64|Papers Count:15

Purpose: The aim of this study was to investigate the shear bond strength of Core Max II® to bovine dentine. Materials and Method: For this purpose 60 sound permanent bovine incisors were gathered and divided into 4 groups of 15.After measuring the buccal enamel by means of radiography, the teeth were embedded in self-cure acrylic blocks. Then the depth gauges were prepared in the buccal side of teeth with straight diamond burs by high-speed hand piece. Next, the buccal enamel was grinded with a model trimmer to reach the specified depth into dentine. Dentine surfaces were polished with voco® composite polishing discs by low speed hand pieces and copious water to obtain a smooth surface free of irregularities. Group 1: In this group Core Max II® was directly bonded to bovine dentine.Group 2: Core Max II® was bonded to bovine dentine etched with 35 % phosphoric acid.Group 3: Core Max II® was bonded to etched bovine dentine by means of a self-cure dentine bonding agent.Group 4: (control group): Para Core was bonded to bovine dentin, which was etched and bonded as. After storing the specimens mentioned before in tap water, they were thermo Scientific-Research Journal I cycled for 500 times between55° & 5°c and were placed under universal testing machine INSTRON 1195 for shear bond testing.Results: The results were as follows: 1. The Shear bond Strength of Core Max II® to bovine dentine was zero and none of the specimens bonded to dentine. 2. Etching bovine dentine slightly increased the shear bond strength (1.27 Map) that although it was significantly higher than the first group, it could not be relied on for proper bonding.1. Application of bonding on etched dentine provided the highest bond strength (10.12 Mpa). 2. The bond strength of Para Core® to etched and bonded dentine was significantly lower than the third group (5.95 Mpa).Conclusion: Thus, in the light of the above - mentioned evidences and results, It can be concluded that Core Max II® cannot bond itself to unprepared dentine and it is imperative to use etching and bonding in order to obtain a good bond strength. Moreover, the other finding of this study was the mean thickness of bovine enamel, which was 1.2 mm in mid-buccal and 1.07 in gingival third and 1.05 in incisor third.

SUI (Stress Urinary Incontinence) means urine leakage when intra - abdominal pressure increases during coughing, laughing and changing position or jumping. Urinary incontinence is a social, physical and psychotic problem that affects the quality of life. 4-8% of women suffer from SUI, therefore, our purpose was to assess the prevalence of SUI after childbirth and to investigate the association between SUI and delivery method. Materials & Method: A prospective cross sectional study was carried out in Tehran university hospitals from April 2003-2004. Therefore, one hundred healthy nulliparas women, without history of urinary tract abnormality, were selected to complete a questionnaire and refill it 4months after delivery. Statistical analysis consisted of chi - square for all variables.Results: From a total number of 702 participants who completed the questionnaires 14.1% suffered the prevalence of urinary incontinence. This rate was 15.9% after normal vaginal delivery, while it was 12.2% after cesarean section. There was no significant difference in prevalence of stress urinary incontinence (SUI) due to the vaginal delivery versus cesarean section performed for obstructed labor. Selective cesarean section with no trial of labor was found to be associated with a significantly lower prevalence of postpartum SUI, (p=0.01). Mothers BMI before pregnancy and fetal weight were two important factors that increase SUI prevalence. Conclusion: Selective cesarean section significantly reduced rate of post partum SUI.

Introduction: Melilotous officinalis, known generally as Melilot is called Nakhonak in medicinal herb market in Iran; for this reason, the same name has been used for it in the Iranian book of medicinal herbs. In Iranian traditional medicine as well as western sources, it has many applications such as: alleviation of thrombophlebitis syndrome and nocturnal leg pains.Objectives: Excessive amounts of this herb have been reported to cause headache; however, moderate consumptions prevent ordinary and migraine headaches. Based on the nitric oxide theory of migraine, migraine attacks are related to high levels of nitric oxide in brain endothelial cells. Therefore, different concentrations of aqueous extract of Melilot fruit were given to endothelial cells.Method: Cultured endothelial cells were exposed to the following concentrations of dry extract of maillot fruit that was dissolved in phosphate buffers of 50,100,200 and 400µg/mL.Results: In control cells (without extract) nitric oxide was found to be 16µg/mL. In 50µg/mL of plant extract, the increase of NO protection by the cells was not significant, whereas at 100µg/mL (p<0.05), 200µg/mL and 400µg/mL (p<0.001), the NO concentrations were significantly different. Conclusion: The effect of Maillot in NO production was not reported previously. If these results are further confirmed in future studies, it maybe concluded that Maillot could be used to increase nitric oxide for the purpose of vasodilatation.

Introduction: The purpose of the root canal treatment is to obtain an appropriate apical seal for prevention of microoraganisms penetrating. The aim of this study was determining the apical leakage after root end resection in canals which were obturated with MTA and Portland cement (PC) in two different lengths.Materials & Method: In this clinical trial, the crowns of seventy single-root human extracted teeth were resected 10mm above the apex. Then, the teeth were divided into four experimental groups and two control groups. Experimental teeth canals were cleaned and flared with the crown down technique by rotary files (Easy Race), saline irrigation, and MAF#40. The whole root of group A & C were filled with MTA and PC, respectively. While, the half of root in group B & D were filled with MTA and PC, respectively. Samples in B & D groups were rapped in moist cotton and were put in incubator for 24 hours. Next, the coronal parts of canals were filled with gutta-percha & AH26 sealer. Later, all the samples were rapped in moist cotton and were put in incubator for 72 hours. After resecting the two millimeter end of all roots, and covering by Nail polish the researchers placed the teeth in 2% Methylene blue dye for 3 days. Finally, the samples were dissected longitudinally for determining dye penetration and apical seal. These were evaluated by using a stereomicroscope (with an accuracy of 0.05). The data were analyzed through using SPSS software (Kolmogrov Smirnov test and ANOVA).Result & Conclusion: It was concluded that, apical seal of PC was significantly better than MTA regardless of the filling length. Moreover, the apical seal of 5mm above the apex was better for both PC & MTA.    

Introduction: Schwannoma (Neurolemmoma) is a benign tumor that originates from Schwann cells with neuroectodermal histogenesis. The Schwannoma has two histopathologic patterns: The Antoni A identified by spindle cells with palisad nuclei and verocay bodies Antoni B is recognized by non-organized pattern of cell - arrangement in myxoid stroma. Nodular fascitis, benign and malignant fibrous histiocytoma, and synovial sarcoma (monophasic type) should be taken into consideration in diagnosis. Purpose: Since accurate diagnosis of lesions is important, the purpose of this study was to compare Antoni A to B staining to find a simple method for differential diagnosis of Schwannomaby histochemical dies.Materials and Method: In the first step, the medical charts of patients with histopathologic diagnosis of Schwannoma were retrieved from central pathology Dept of Imam Khomeini hospital. The Haematoxylin -Eosin (H&E) stained sections were studied and 7 sections with prefect fixation were 'selected. Sections of three micron were prepared and stained with H&E, trichrome masson, Periodic acid – Schiff (PAS)and kajal silver. Using double blind method, all sections were studied by two pathologists. Results: The results indicated that, the cells in Antoni A were better identified than Antoni B with PAS. With trichrome masson, the Antoni A was negative, but in some part of Antoni A and myxoid areas, the blue stains were seen. Both Antoni A and B were deeply stained with kajal silver. Conclusion: Based on our findings, it seems that the application of PAS/H&E together with kajal silver staining is a useful method for differential diagnosis of Schwannoma.

Background and Objectives: Severe maternal anemia is accompanied with increasing the risk of low birth weight (LBW), still birth, spontaneous abortion and preterm delivery. This study was aimed to determine the association between maternal hemoglobin and hematocrit levels with neonatal pregnancy complications at birth via logistic regression model.Material & Method: A cross-sectional study was conducted with 903 women who were admitted -to Babol Yahyanejat hospital for delivery in 2004. Mothers with twin delivery, diabetes, severe bleeding before and during delivery and mothers with apparent congenital neonates were excluded. The standard blood examination was carried out before delivery for measuring maternal hemoglobin and hematocrit levels. The data related to maternal age, sex of infant, residence area, maternal education, number of pregnancy, parity, number of visits for prenatal cares, type of delivery and the neonatal pregnancy outcomes (LBW, preterm, the need for special care and apgar score in the first minute) were collected by using questionnaires and hospital charts. In statistical analysis, the multiple logistic regression model was used to determine the adjusted odds ratio of the effect of low and high hemoglobin and hematocrit (versus moderate) levels on the risk of pregnancy outcomes. The odds ratio and its 95% confidence interval were estimated after adjusting the effect of maternal age, maternal education, residence area, number of pregnancy, sex of infant and the number of prenatal visits.Results: The maternal hematocrit in 15.4 percent of subjects was 33 or less. 58.8% of subjects were 33-40 and 25.8% were more than 40 years old. The maternal hemoglobin level in 6.4% of subjects was less than 10.5. In 61.9% of subjects it was 10.5 to 13, while in 31.7% it amounted to more than 13. The prevalence of LBW was 10.17%. Further more, the pre-maturity was 14.5% in neonates with maternal Hb of less than 10.5. These rates were almost two times greater than those subjects with Hb of 10.5-13. The adjusted odds ratio of hematocrit of less than 34, compared to hematocrit of 34-40, on the risk of LBW was 1.4 times (95%CI: 6.65-2.99). On the other hand, the adjusted odds ratio for the risk of pre-maturity was 1.25 times (95% CI: 0.62-2.64). However, the adjusted OR for the risk of need for special cares was 1.57 times (95%CI: 0.72-3.4). It was 1.65 times (95% CI: 0.72-3.4) for the effect of Hb less than 10.5 (compared to Hb of 10.5-13) on the risk of LBW. This effect was 2.37 times (95%CI: 1.01-5.57) on the risk of special - cares and hospitalization it was 1.57 times (95%CI: 0.57-4.38). Conclusion: It can be concluded that the low and high hematocrit levels in pregnant women increase the risk of pre-maturity and LBW. Thus, it may require further considerations in prenatal management of pregnant women.

Introduction: One of the important challenges in periodontics is deep intrabony defects especially angular defects. It may have an important role in losing the teeth after the furcation complications. To date, a lot of Resective and Regenerative treatments have been done with graft materials. The present study aims at clinical and radiographical evaluation of treatment of two or three-walled bone defects by Iranian Neo-os.Material & Method: The present study is an interventional or clinical trial. This study was carried out for 12 two or three-walled bone defects in patients aged 20 to 50. These defects were surgically treated by placement of the Iranian Neo-os. Measurements of Probing Pocket Depth (PPD) and Clinical Attachment Level (CAL) were recorded at baseline and 6 month after the surgery. Also Plaque Index (PI) of patients was recorded every 6 months. Bone-filling rate was computed by Radio Visio Graphy (RVG) at baseline and 6 month after the surgery, then, it was compared to Flap Curettage method. Results: The PPD mean before surgery was 7.16 mm and 6 month after surgery it was 4.16 mm. This PPD mean reduction was statistically significant. The CAL mean before the surgery was 6.66 mm and 6 month after the surgery it was 4.25 mm. This CAL mean reduction was also statistically significant. The mean Bone Fill treatment by Neo-os was 1.64 mm and by Flap Curettage was 1.19 mm. Although the Bone-fill mean by Neo-os was more than Flap Curettage, there was no significant difference. Conclusion: The results show that Iranian Neo-os can be used as a graft material in the regenerative method; nevertheless, further studies with more samples, long term follow ups and histological evaluation are suggested.

Introduction: The periodontal infra-bony damages and their familiar symptoms are quite prevalent. Many companies producing Gerasorb and Bio-oss osteogeneses claim that they are successful in restoring these damages. Thus, the researchers aimed at comparing the effects of such osteogenesis products. The study was conducted for the patients with periodontal infra-bony lesions who were referred to the periodontics department during 2002-3.Materials & Method: Glinincal tests of sequential randomized single blind trial were performed. The subjects were volunteers (aged 35-55) with no records of systemic disease, smoking habit or drug therapy. Lesions were detected by standard probing, radiography for the situation, number and intensity of damages. Furthermore, the depth of pack, P.D. situation and C.A.L. positions were measured through radiography, loosening and B.O.P. methods. The subjects were divided into two Bio-oss and cerasorb control groups, then the above - mentioned indexes were checked based on the standards within 1, 2 and 3 month intervals. The P.D. and C.A.L. changes and the depth of pack in radiography were measured through paired T-test for each group. The inter-group differences were computer by T-test. In addition, B.O.P. and loosening changes were determined through sign tests. For this purpose, six patients with sixteen periodontal infra-bony lesions (each with 8 lesions) participated in the experiment. Their mean age was 41±5. Results: Those who had received Bio-oss treatment, showed a P.D. change from 4.7±2.3mm to 2.9±1.5mm. There was a significant difference of 1.85±3mm in P.D. situation (p<0.001). However, in the Cerasorb group it had changed from 5.1±2.3mm to 3.5±1.2mm, which was also significant. With regard to the CAL. position, loosening and B.O.P. indexes, no significant differences were observed within the groups (p<0.001), while there were significant differences between the groups (p<0.001). In relation to the depth of pack in radiography, Bio-oss had better and more successfully restored the damages. Thus, when the means of both control groups are compared, the preference of Bio-oss to Cerasorb is approved.Conclusion: Considering the fact that Bio-oss osteogenesis functions better than Cerasorb in restoring periodontal infra-bony defects arid their identical price and availability, Bio-oss is more preferable to its similar product. However, further research should be carried out with larger samples.  

Introduction: This study aimed at assessment and evaluation of the effect of ergonomic intervention on reducing musculoskeletal disorders. Materials and Method: In order to keep a record of the history of the individuals suffering from WMSDs, questionnaires were distributed among the dentists to evaluate their working - posture. Rapid Entire Body Assessment (REBA) was adopted as observational technique. In order to perform ergonomic optimization of working - posture, the principles of human - centered ergonomics were taught. These principles are called "Performance Logic", since they allow individuals to pose the most natural method of practice in dentistry without having to risk one's health, job or patient.Results: The results showed that over 90% of the dentists complained about pain in at least one part of their body during last year. Most individuals suffered from neck (63%) and shoulder (62%) pain. 10 to 15 percent of the dentists had work - related absenteeism due to these disorders. The findings of REBA indicated that 94% of the dentists were above moderate risk range, 60% of the individuals were at medium risk level and 34% had high-risk level. These results confirmed the necessity and emergency of effective ergonomic interventions for dental care workers. After intervention, the REBA scores and risk level were significantly reduced (p<0.05). The feeling of pain in the neck, shoulder and upper back also significantly decreased. However, the pain in other organs did not change dramatically.Conclusion: Following the principles of "performance logic", dentists can offer better oral-care; they can also increase their productivity and profitability.

Introduction: The solitary pulmonary nodule is the first radiographic finding in 20-30% of lung cancers. Therefore, it is important to distinguish malignant from benign cases. Many studies reported initially radiological evaluation; especially HRCT is the most helpful method to show the margin, size, and internal characteristics of pulmonary masses. The aim of this study was to evaluate HRCT findings and biopsy results and find the correlation between them.Method: 196 patients who underwent transthorasic or transbronchial biopsies in Mostafa Khomeini hospital were evaluated for 2 years. The factors noted in HRCT included: size, location, margin and internal characteristics of pulmonary mass. After collecting the data, 59 patients were excluded because there were no enough documents for them. Finally, data were entered into computer and analyzed by SPSS soft ware. Results: 54% of patients were male and 46% were female. Biopsy results were malignant in 43.8% cases but 56.2% were benign or nonspecific. The Malignant group included: SCC, NSCC, and metastases. However, TB, sarcoidosis, antracosis, Boop, Bronchestasia and other diseases were included in benign group. 42.3% of benign nodules well-defined, on the other hand, 2.2% had irregular margins. The most homogeneous view belonged to benign groups. Airbronchogram was seen in 28.5% of malignant group. While calcification was common in benign group, in malignant group, the most nodules were in upper lobes of lung. There were significant difference between malignant and benign groups, in case of age, the location, size, margin, cavitations and airbronchoram view.Conclusion: Specific morphologic features such as size, margin and internal characteristics (especially Heterogeneity) are helpful to distinguish benign from malignant masses if the patient's history and major factors that increase the risk of malignancy are taken into considerations.

Introduction: Fissure sealant is a safe and effective method to prevent dental caries, especially occlusal surface caries of posterior teeth. Many investigations have been carried out to evaluate sealant efficacy on caries prevention. The purpose of this study is the effect of total and self – etching systems on micro leakage of pit using fissure sealant and flow composite in permanent teeth. Materials & Method: Sixty non-caries maxillary premolar were chosen to represent the anatomy fissure for fissure sealant. No invasive technique was used. The premolars were randomly divided into 4 groups of 15. . Group A: Acid etch + single bond + flow composite . Group B: Acid etch + Fissure sealant. Group C: Self-etch + flow composite. Group D: Self-etch + Fissure sealant.The sample was thermo cycled for 500 times at 5-55 degrees Celsius and was immersed 1n %2 basic Fuchin for 24 hours. Then, all teeth were embedded in clean self-cured acrylic and bucco - lingually sectioned. They were examined for dye penetration under a stereomicroscope (40 X). For micro leakage analysis at the section level by proportional Odda model, link function and goodness of fit (0.760). Results: There is no significant difference in using the self-etching or total etching systems but significant differences were found in using flow composite and fissure sealant. Micro leakage is less, when fissure sealant is used and compared to flow composite.