Statement of Problem: In a previous study it was reported that a durable resin-ceramic tensile bond could be obtained by an appropriate silane application without the need for HF acid etching the ceramic surface. Evaluation of the appropriate application of silane by other test methods seems to be necessary.Purpose: The purpose of this study was to compare the interfacial fracture toughness of smooth and roughened ceramic surfaces bonded with a luting resin.Materials and Methods: Ceramic discs of 10 mm in diameter and 2 mm in thickness were prepared.Four different surface preparations (n=10) were carried out consisting of (1) ceramic surface polished to a 1µm finish, (2) gritblasted with 50µm alumina, (3) etched with 10% HF for 2 min, and (4) gritblasted and etched. The ceramic discs were then embedded in PMMA resin. For the adhesive area, the discs were masked with Teflon tapes. A circular hole with diameter of 3 mm and chevron-shaped with a 90° angle was punched into a piece of Teflon tape. The exposed ceramic surfaces were treated by an optimised silane treatment followed by an unfilled resin and then a luting resin cylinder of 4mm in diameter and 11 mm in length was built. Specimens were stored in two different storage conditions: (A): Distilled water at 37°C for 24 hours and (B): Distilled water at 37°C for 30 days. The interfacial fracture toughness (GIC) was measured at a cross-head speed of 1 mm/min. The mode of failure was examined under a stereo-zoom microscope and fracture surfaces were examined under Scanning Electron Microscope.Results: The mean interfacial fracture toughness values were; Group A: 1) 317.1±114.8, 2) 304.5±109.2, 3) 364.5±169.8, and 4) 379.4±127.8 J/m2±SD. Group B: 1) 255.6±134.4, 2) 648.0±185.1, 3) 629.3±182.6 and 4) 639.9 ±489.0 J/m2±SD. One way Analysis of Variance showed that there was no statistically significant difference in the mean interfacial fracture toughness for groups A1-A4 (P>0.05). However, the mean interfacial fracture toughness for group B1 was significantly different from that for groups B2, B3 and B4 (P<0.05). Independent-ٍٍٍSamples T-Test results showed that there was a significant increase in the GIC mean value for groups B2 and B3 after 30 days water storage (P<0.05). The modes of failure were predominantly interfacial or cohesive within the resin.Conclusions: The fracture toughness test method used in this study would be appropriate for analysis of the adhesive zone of resin-ceramic systems. From the results, it can be concluded that micro-mechanical retention by gritblasting the ceramic surfaces could be sufficient with no need for HF acid etching the ceramic surfaces when an appropriate silane application procedure is used.

Nonunion of tibial stress fracture has been reported in athletes and only in proximal and midshaft of tibia. We have found no report of nonunion of a stress fracture in distal tibiofibula. Report of this lesion, especially in a non-athlete adolescent, is interesting and important.

Statement of Problem: Evaluation of fracture properties is a basic principle for true assessment of brittle materials’ properties. Resin–based composite materials are being used extensively in today’s dentistry. Fracture toughness is considered an important parameter for providing useful information about material’s nature, properties and its resistance to fracture. Purpose: The purpose of this study was to evaluate the fracture toughness of a resin composite produced in the country and to compare it with that of other standard materials. Materials and Methods: Four types of resin composite materials were used as follow to prepare 60 specimens (n=15 for each group), A) Tetric Ceram (Ivoclar–Vivadent); B) Brilliant (Coltene-Whaledent); C) SpectrumTPH (Dentsply); and D) Ideal Macoo (Ideal Macoo, Iran). Specimens of 5 mm diameter (± 0.1 mm) and 2 mm depth (±0.1 mm) were prepared in a central notch (90° notch angle) PTFE mold. Then specimens were light cured with two applications of overlapping exposures for a total of 120 s and were stored in distilled water at 37ºC for 48 hours, A cylindrical roller of 3 mm diameter was seated inside the V sections and fracture was accomplished in a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed by one–way ANOVA and post-hoc paired Tukey HSD test with P<0.05 as the limit of significance. Results: The mean KIC and torque to fracture (T) values for each material tested were; A) 3.08±0.42, 16.99±2.34, B) 2.88±0.63, 16.04±1.98; C) 3.40±0.53, 18.75±2.93 and D) 2.87±0.46, 15.78±2.57 MN/m3/2±SD and N/mm±SD, respectively. Group C showed significantly the highest mean KIC and T values among groups tested which was significantly higher than that of group B and D (P<0.05). The mean KIC and T values for groups A, B, and D were not significantly different (P>0.05). Conclusion: From evaluating the fracture properties of materials tested in this study it was concluded that the mean fracture toughness value for SpectrumTPH (Dentsply) was significantly higher than that of Ideal Macoo resin composite material (Ideal Macoo, Iran). The F.T value for Ideal Macoo was considered acceptable as it was not significantly different from that of other resin composite materials tested.  

Percutaneous vertebroplasty is a promising therapeutic technique for pain control in patients with pathologic fractures of vertebral bodies. Percutaneous vertebroplasty is an appropriate treatment for vertebral pathologic fractures, which is resistant to other usual treatment. It is a useful and only choice in special cases, because of less tissue damage and there is no risk of open surgery and patient's embolization is rapid. Herein we described the first case of percutaneous vertebroplasty in Yazd shahid sadoughi teaching hospital, which was done in ordybehesht 1386 in a 72 years old male with pathologic fracture of 2 lumbar vertebrae. He was suffered from pain and disability and open surgery was not appropriate treatment for him.

Stress fracture is a common diagnosis of pain in the lower extremity in the lack of obvious trauma history. Nowadays, with better recognition of its pathophysiology and advanced diagnostic facilities, it is more convenient to distinguish stress fracture. But in some cases, it is troublesome to differentiate stress fracture from serious conditions such as neoplasm. The current case report described an unusual case of proximal fibula stress fracture presenting with mass and local tenderness without history of trauma or vigorous activity.

Background: Stress fractures develop when a bone cannot remodel in response to repetitive force. They are less frequent in the upper extremities, and the coronoid process is an infrequent site for stress fractures. Coronoid stress fractures present with pain and tenderness of the elbow, which is exacerbated by full extension of the elbow. Case presentation: A 24-year-old male boxer was admitted to the hospital after complaining of pain in the anterior part of his elbow for the past seven months. Physical examination revealed exacerbation of pain during hyperextension positions and training, tenderness of the elbow at the anterior region, and decreased range of motion. Coronoid stress fractures should be considered in athletes, especially gymnasts with chronic elbow pain. Initial treatment is conservative management of the pain. If conventional treatment fails, fixation of the fragment with a surgical approach and subsequent rehabilitation must be performed.

Introduction: Medial malleolar stress fractures are rare injuries resulting from excessive and repetitive stress loads on bone. The incidence rate of these stress fractures varies from 0.6% to 4.1% of all stress fractures and has been almost exclusively reported in athletes. Typical clinical presentation is a gradual onset of pain and tenderness at the medial malleolus site with a history of long-term physical activity.  Presentation: A 60-year-old postmenopausal woman with a gradual onset of pain and point tenderness over the medial malleolus and a history of daily walking for several months. Diagnosis: The initial anterior-posterior and lateral plain radiographs were normal. After the initial conservative medication therapy failed, magnetic resonance imaging (MRI) was obtained. It demonstrated a vertical linear zone of decreased signal intensity originating between the tibial plafond and the medial malleolar junction, which suggested medial malleolar stress fracture.  Intervention: We started treatment with a short leg cast and non-weight bearing for six weeks that failed; open reduction and internal fixation were performed under general anesthesia.  Outcomes: Six months postoperatively, the pain entirely resolved, and the patient returned to her regular daily physical activity and conducted plain radiographs demonstrating complete union, and no complications occurred. Conclusion: Medial malleolar stress fractures are rare injuries and might be misdiagnosed due to normal initial radiographs. They must be considered in those with gradual onset of pain and point tenderness of medial malleolus, especially with a history of long-term physical activity. Early diagnosis and surgical intervention lead to faster healing and a return to physical activity

Background: The most frequently used test for evaluation of fetal health is the Non Stress Test (NST). Unfortunately it has a high incidence of false positive results. The combination of vibroacoustic stimulation with the NTS has been shown to reduce non reactive results.Methods: A tests assessment method was chosen with a simple randomized sampling. 40 pregnant women with non reactive NST in the first 20 minutes who received VAS in one of Tehran University's Hospitals were compared with BPP scores. A vibroacoustic stimulation was applied for a 3 seconds on the maternal abdomen and fallowed within 10 minutes. Data collection tools were NST, sonography instruments, NST result paper, tooth brusher, watch, demographic questioner and check list. Data analysis was made by descriptive static and by using the Fisher's Exact Test (with level of significant at p<0/05). All statistical analysis were performed using an spss/win.Results: After VAS, 70% of non reactive tracing became reactive. All cases with fetal reactivity response after a VAS had a subsequent BPP score of 8 (negative predictive value of 100%). False positivity of VAS was lower than NST.Conclusion: VAS offers benefits, by decreasing the incidence of non reactive test and reducing test time. VAS lowers the rate of false positive NST. VAS is safe and allows more efficient of prenatal services. This test could be used as a rapid antepartum test to predict fetal well-being.

Background and Aim: According to the importance of trigemino cardiac reflex (TCR) and also prevention and management of this reflex in maxillofacial surgeries, the present study was held to evaluate the TCR In lefort I osteotomy. on patients who came to Surgical Department of Buali hospital and the private office in 1386-87.Material and Method: The study was held on 30 patients at the age of 18-39 which were candidate for osteotomy lefort I surgery. TCR was defined as a drop in mean arterial blood pressure (MABP) and heart rate (HR) of more than 10% to the baseline values before maxillary down fracture (D.F) and coinciding with D.F. Hemodynamic parameters such as HR and MABP evaluated with continuous monitoring in different times (before, during and after down fracture of maxilla). Changes in upon characteristics were analyzed.Results: 5 patients were excluded for different reasons and study was completed on 25 patients. Age of the patients was 24.6±1.6, 30% male, and 70% female. The mean HR fell 6.5% from a mean of 94.29±12.12 beats/min, before D.F to a mean of 88.08±13.6 beats/min during D.F, returning to a mean of 93.92±13.09 after D.F. The MABP fell 9.7% from to a mean of 103±15.89 mmHg before D.F to a mean of 92.99±15.19 during the D.F, returning to a mean of 99.69±13.123 after D.F. The HR and MABP after DF were not significantly different from baseline values before the DF. The mean HR drop of more than 10% to the baseline values before DF and coinciding with DF, in 25% of the patients, and also about the MABP, it fell in 45.8% of the patients.Conclusions and suggestions: The present results give evidence that stimulation or manipulation of maxillary branch of the trigeminal nerve can cause TCR, leading to a significant decrease in HR and MABP under a standardized anesthetic protocol. Further studies preferably with a multicenter design are necessary to confirm the nature, description. predisposing and triggering factors and other aspects of this seemingly physiologic phenomenon.

Nowadays total joint replacements are widely used in the world, so in average 800,000 joint surgeries are done yearly only in Europe and North America. However implant loosening is and remains as the major issue of all implant failures and therefore causes revision surgery procedures. Studies and experiments have identified poor fixation of implants most likely is the main cause of long term implant failure and in this case the cement-implant interface cavities are very effective due to resultant stress concentration. In this study the theory of this problem, continuum and mathematical equations for an inhomogeneous material by using Eshelby’s equivalent inclusion method with a spherical void as a special type of inhomogenities is addressed and a new yield criterion with respect to the void’s volume fraction is derived and changes in material elasticity tensor concerning Mori-Tanaka’s theorem also determined, then by using finite element method and remeshing technique a macro scale cement-implant interface cavity is modeled and concerning the loss of strength due to void existence and the interface stress concentration, the crack initiation and propagation  phenomenon is numerically investigated with respect to different orthopedic cement material properties. The results show that crack propagates at the interface at constant stress and strain by elastoplastic material and it propagates in cement bulk by considering elastic material properties for cement that both could cause implant loosening even in very small void’s volume fractions in which there are no significant changes in cement yield stress and elasticity tensor according to analytical solution. But numerical simulation shows that when a homogenous cement structure is achieved via high vacuum mixing method, there is a uniform stress distribution in the cement structure and no stress concentration zone forms even at high stress levels and also there is no appropriate local site for crack initiation.