Evaluation of bond strength of pressed and layered veneering ceramics to nickel-chromium alloy

Statement of the Problem: The success of metal- ceramic- restorations [MCR] depends on the presence of strong bond between porcelain and metal substructure

Purpose: The purpose of this study was to evaluate the effect of hot pressing technique on the bond strength of a metal-porcelain composite in comparison to layering technique

Materials and Method: Thirty Nickel-Chromium specimens were produced by two methods; conventional porcelain layering on metal and hot pressing [n=15]. Bond strengths of all specimens were assessed by the means of three-point bending test according to ISO 9693: 1999 [E] instructions. The data were analyzed using Students t-test [p< 0.001]

Results: The mean +/- SD bond strength of conventional and hot pressing technique was 48.29 +/- 6.02 and 56.52 +/- 4.97, respectively. Therefore, the conventional layering technique yielded significantly lower mean bond strength values than hot pressing technique [p< 0.001]

Conclusion: This study showed that it is possible to improve metal-porcelain bond strength significantly by applying an overpressure during porcelain firing

Neonatal bacteriemia isolates and their antibiotic resistance pattern in neonatal insensitive care unit [NICU] at Beasat hospital, Sanandaj, Iran

Bacteremia continues to result in significant morbidity and mortality, particularly among neonates. There is scarce data on neonatal bacteremia in among Iranian neonates. In this study, we determined neonatal bacteremia isolates and their antibiotic resistance pattern in neonatal insensitive care unit at Beasat hospital, Sanandaj, Iran. During one year, all neonates admitted to the NICU were evaluated. Staphylococcal isolates were subjected to determine the prevalence of MRS and mecA gene. A total of 355 blood cultures from suspected cases of sepsis were processed, of which 27 [7.6%] were positive for bacterial growth. Of the 27 isolates, 20 [74%] were Staphylococcus spp as the leading cause of bacteremia. The incidence of Gram negative bacteria was 04 [14.8%]. The isolated bacteria were resistant to commonly used antibiotics. Maximum resistance among Staphylococcus spp was against Penicillin, and Ampicillin. In our study, the isolated bacteria were 7.5% Vancomycin and Ciprofloxacin sensitive. Oxacillin disk diffusion and PCR screened 35% and 30% mec a positive Staphylococcus spp. The spectrum of neonatal bacteremia as seen in NICU at Beasat hospital confirmed the importance of pathogens such as Staphylococcusspp. Penicillin, Ampicillin and Cotrimoxazol resistance was high in theses isolates with high mecA gene carriage, probably due to antibiotic selection

evaluation of perioperative safety of local anesthesia with lidocaine containing epinephrine in patients with ischemic heart disease

The use of local anesthesia with lidocaine containing epinephrine in patients with cardiac disease is controversial in the literature. The aim of our study was determining the safety of use the local anesthesia contain epinephrine in patients with ischemic heart disease that undergoing reconstructive surgery. Thirty two patients that had known ischemic heart disease and candidate to undergo reconstructive surgery for skin tumor enrolled in this study. All patients continued their medication for cardiac disease till morning of the operation. 10 ml lidocaine 2% containing 1:100,000 epinephrine was injected in patients for local anesthesia. The hemodynamic changes and electrocardiographic variables before injection were compared with them after injection, during surgery and till 6 hours postoperation period. A 12 lead electrocardiogram was recorded in all our cases for detection of myocardial ischemic changes. The mean age, weight and height were 58.2 +/- 10.4, 74.8 +/- 14.4 kg and 164.5 +/- 8 cm respectively. Twelve patients [37.5%] were diagnosed with systemic hypertension and 10 patients with diabetes [31.2%]. The comparison of change of systolic, diastolic and mean blood pressure between baseline, during procedure and after operation defined that our subjects did not have any significant disturbance in blood pressure in perioperative period. The comparison of baseline heart rate with heart rate after injection, during procedure and in postoperation period indicated a significant changes in this variable [P=0.044]. The heart rhythm during the perioperative period also failed to exhibit alterations. The ischemic change was not recorded in our patients before injection compared to after injection. None of our patients have any early complications because of infiltration of local anesthetic containing epinephrine in our patients. The use of 10 ml 2% lidocaine with epinephrine 1:100,000 in patients with cardiac disease represent a safe anesthetic procedure. These patients experienced a more profound anesthesia with hemodynamic stability and without myocardial ischemic changes.

Comparison of post-operative neurological complications between on-pump and off-pump coronary artery bypass surgery

To assess neurological impairment after the off-pump and On-pump techniques in patients with first-time isolated coronary artery bypass graft surgery. One hundred twenty patients undergoing first-time isolated coronary artery bypass graft surgery prospectively at Baqiatallah University Hospital, Tehran, Iran were randomised to the off-pump or on-pump technique. Change in NIHSS score was measured at 30 days postoperatively. The on-pump group showed a significantly greater deterioration in scores than the off-pump group. The incidence of TIA at 30 days postoperatively was 15.3% [9 out of 60] in the on-pump group and 5% [3 out of 60] in the off-pump group. [P=0.05]. The incidence of Stroke at 30 days postoperatively was 3.4% [2 out of 60] in the off-pump group, while no one from off-pump group suffered from stroke. [P=0.05] Off-pump coronary artery bypass graft surgery results in less neurological impairment than the on-pump technique

Investigation of deep sternal wound infection after coronary artery bypass graft and its risk factors

To investigate factors that predict sternal wound complications in patients after coronary artery bypass grafting [CABG] because prediction of deep sternal wound infection after surgery, might help us to do some interventions and reduce its consequences. The record of all these patients was reviewed retrospectively. DSWI was defined according to the guidelines of the Centers for Disease Control and Prevention. From Sep 2003 to Sep 2006 a total of 1014 patients who underwent coronary bypass graft surgery in a cross-sectional study was included in this study. Logistic regression analysis was conducted and the risk factors that significantly predicted sternal wound complications after coronary artery bypass graft surgery included older age, Diabetes mellitus, increasing BMI, and in class three or four of the New York Heart Association functional class. Most infections had a late and the majority of these were caused by staphylococcus epidermidis while other were pseudomonas aeroginosa, streptococcus pneumonia, staphylococcus aureus and one of them was Meticilline resistance. The clinically most fulminate infections were caused by e-coli and presented early after surgery. Advanced age, diabetes and obesity, NYHA high score were the important risk factors identified. As such we suggest more attention should be paid to these patient. Modifying the risk factor and making decision according to risk factor such as appropriate administration of prophylactic antibiotic in patient with poor physical status, good control diabetes are recommended