Fatigue resistance and microleakage of CAD/CAM ceramic and composite molar crowns

Purpose: The aim of this study was to determine effect of compressive cyclic loading on fatigue resistance and microleakage of monolithic CAD/CAM molar ceramic and composite crowns. Materials and Methods: Thirty‐two extracted molars were prepared to receive CEREC crowns according to manufacturer's guidelines using a special paralleling device (Parallel‐A‐Prep). Sixteen feldspathic ceramic crowns (VITABLOCS Mark II) (VMII) and 16 resin‐composite crowns (Paradigm‐MZ100 blocks) (PMZ) were milled using a CEREC‐3D machine. Eight crowns of each group were cemented to their respective teeth using self‐etching resin cement (Panavia‐F‐2.0) (PAN), and eight were cemented using self‐adhesive resin cement (RelyX‐Unicem‐Clicker) (RXU). Following storage for 1 week in water, specimens were subjected to uniaxial compressive cyclic loading in an Instron testing machine at 12 Hz for 1,000,000 cycles. Load was applied at the central fossa, and the cycle range was 60–600 N. Specimens were then subjected to microleakage testing. Data were statistically analyzed using factorial ANOVA and Post Hoc (Tukey HSD) tests. Results: All composite crowns survived compressive cyclic loading without fracture, while three ceramic crowns from the subgroup cemented with RXU developed surface cracks at the center of occlusal surfaces, extending laterally. Microleakage scores of ceramic crowns cemented with PAN were significantly lower than those of the other three subgroups (p < 0.05). Conclusions: After 1,000,000 cycles of compressive cyclic loading, PMZ composite molar crowns were more fatigue‐resistant than VMII ceramic crowns. Cement type had a significant effect on fatigue resistance of the ceramic crowns but not the composite ones. Microleakage scores of ceramic crowns cemented with PAN were significantly lower than those of the other subgroups (p < 0.05).     

Screening and detection of human papillomavirus (HPV) high-risk strains HPV16 and HPV18 in saliva samples from subjects under 18 years old in Nevada: a pilot study

Background

Human papillomaviruses (HPV) are oncogenic and mainly associated with cervical cancers. Recent evidence has demonstrated HPV infection in other tissues, including oral epithelia and mucosa. Although a recent pilot study provided new information about oral HPV status in healthy adults from Nevada, no information was obtained about oral HPV prevalence among children or teenagers, therefore, the goal of this study is to provide more detailed information about oral prevalence of high-risk HPV among children and teenagers in Nevada.

Methods

This retrospective study utilized previously collected saliva samples, obtained from pediatric dental clinic patients (aged 2 – 11) and local school district teenagers (aged 12-17) for high-risk HPV screening (n=118) using qPCR for quantification and confirmation of analytical sensitivity and specificity.

Results

A small subset of saliva samples were found to harbor high-risk HPV16 (n=2) and HPV18 (n=1), representing a 2.5% of the total. All three were obtained from teenage males, and two of these three samples were from White participants.

Conclusions

Although this retrospective study could not provide correlations with behavioral or socioeconomic data, this project successfully screened more than one hundred saliva samples for high-risk HPV, confirming both HPV16 and HPV18 strains were present in a small subset. With increasing evidence of oral HPV infection in children, this study provides critical information of significant value to other dental, medical, oral and public health professionals who seek to further an understanding of oral health and disease risk in pediatric populations.

     

MDCT to guide transcatheter aortic valve replacement and mitral valve repair

Percutaneous management of valvular heart disease is becoming a reality, with multicenter trials supporting minimally invasive procedures for both aortic and mitral valve disease. Historically, the treatment of choice has been aortic valve replacement with conventional surgery for patients with severe aortic stenosis, as the prognosis of untreated patients is poor, particularly if the patient is symptomatic. Transcatheter aortic valve replacement is now available as a minimally invasive option to treat select high-risk patients with severe aortic stenosis. At present more than 30,000 procedures have been performed worldwide, mostly confined to patients at high surgical risk. The short- and medium-term outcomes have been promising.     

Characterization of primary isolates of HIV type 1 CRF28_BF, CRF29_BF, and unique BF recombinants circulating in São Paulo, Brazil

We report for the first time the genetic and biological characterization of 10 HIV-1 primary isolates representing CRF28_BF and CRF29_BF together with additional unique BF recombinant forms (URFs) obtained by PBMC cocultivation. Recombination is an important factor promoting the increase in the genetic diversity of HIV-1. Notably, more than 20% of HIV-1 sequences worldwide were recombinants. Several recombinant viruses were reported in Brazil, and six circulating recombinant forms (CRFs) have been identified (CRF28_BF, CRF29_BF, CRF31_BC, CRF39_BF, CRF40_BF, and CRF46_BF). CRF28_BF and CRF29_BF were found to infect almost 30% of the patients in S?o Paulo State. The near full-length genomes of these 10 primary isolates were amplified by nested PCR in three overlapping segments, purified, and sequenced. Three samples were related to CRF28_BF, three to CRF29_BF, and four were unique recombinant forms (URFs), as determined by their breakpoint profile determined with the jpHMM program. Additionally, the coreceptor usage of these isolates was investigated in vitro using GHOST assays, which revealed three dual-tropic (X4/R5) viruses, four lymphotropic (X4) viruses, and three macrophage-tropic (R5) viruses with different V3-loop motifs, which challenges the notion that GWGR-carrying viruses are macrophage-tropic only. In sum, we report a much-anticipated well-characterized panel of viruses representing CRF28_BF, CRF29_BF, and URFs from S?o Paulo State, Brazil.     

Peripheral blood gene expression profile of atherosclerotic coronary artery disease in patients of different ethnicity in Malaysia

The molecular basis of coronary artery disease (CAD) has been widely studied in the western world but there is no published work on the Malaysian population. This study looked at the global gene expression profiling of the peripheral blood of patients with CAD from the 3 main ethnic groups in Malaysia. Male subjects selected were based on angiographically confirmed CAD (≥50% stenosis) and normal control subjects (0% stenosis) with age range of 55.6±5.3 and 51.0±5.5years, respectively. The global gene expression of 12 angiographically documented CAD patients and 11 matched control subjects were performed. The combined group samples identified 6 up regulated differential expression (DE) genes (GHRL, LTA, CBS, HP, ITGA2B, and OLR1) and 12 down regulated DE genes (IL18R1, ITGA2B, IL18RAP, HP, OLR1, SOD2 ITGB3, IL1B, MMP9, PLA2G7, UTS2, and CBS) to be involved in CAD at the fold change of 1.3 with fault discovery rate (FDR) of 1%. Three genes, MMP9, IL1B, and SOD2 were down regulated in all the 3 ethnic groups making them potential biomarker candidates for CAD across all three ethnicities. Further verification in a cohort study is needed.     

Impact of type of thrombolytic agent on in-hospital outcomes in ST-segment elevation myocardial infarction patients in the Middle East

Little is known about the impact of thrombolytic agents on in-hospital outcomes in the Middle East. The objective of this study was to evaluate the impact of thrombolytic agents on in-hospital outcomes in ST-segment elevation myocardial infarction (STEMI) patients in six Middle Eastern countries. Gulf Registry of Acute Coronary Events was a prospective, multinational, multicentre, observational survey of consecutive acute coronary syndrome patients admitted to 65 hospitals in 2006 and 2007. Out of 1,765 STEMI patients admitted to hospitals within 12 h of symptoms onset, 25, 43, and 30% were treated with streptokinase, reteplase, and tenecteplase, respectively. Median age of the study cohort was 50 (45–59) years and majority were males (89%). The overall median symptom onset-to-presentation and median door-to-needle times were 130 min (65–240) and 45 min (30–75), respectively. Streptokinase patients had worse GRACE risk scores compared to patients who received fibrin specific thrombolytics. Academic hospitals and cardiologists as admitting physicians were associated with the use of fibrin specific thrombolytics. After significant covariate adjustment, both reteplase [odds ratio (OR), 0.38; 95% CI: 0.18–0.79; P = 0.009] and tenecteplase (OR, 0.30; 95% CI: 0.12–0.77; P = 0.012) were associated with lower all-cause in-hospital mortality compared with streptokinase. No significant differences in other in-hospital outcomes were noted between the thrombolytic agents. In conclusion, in light of the study’s limitations, fibrin specific agents, reteplase and tenecteplase, were associated with lower all-cause in-hospital mortality compared to the non-specific fibrin agent, streptokinase. However, the type of thrombolytic agent used did not influence other in-hospital outcomes.     

High-sensitivity C-reactive protein (hs-CRP) in systemic lupus erythematosus patients without cardiac involvement; relation to disease activity,damage and intima-media thickness

Aim of the workTo assess the high sensitivity C-reactive protein (hs-CRP level) in systemic lupus erythematosus (SLE) patients without cardiac involvement and find its relation with clinical and laboratory findings, disease activity, damage index and intima-media thickness (IMT).Patients and methodsForty-five female SLE patients were recruited in the present study without any cardiac involvement. History taking, examination and laboratory investigations were performed for patients. Disease activity was evaluated by the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and damage by the Systemic Lupus International Collaborating Clinics (SLICC) index. Thirty age matched female healthy subjects were considered as a control group. hs-CRP was measured quantitatively by microplate immunoenzymometric assay and the IMT measured by ultrasonography.ResultsThe hs-CRP in the patients was significantly higher (4.84 ± 3.91 mg/l) compared to the control (1.74 ± 0.61 mg/l) (p < 0.001). The IMT in the patients was significantly increased (0.72 ± 0.37 mm) compared to the control (0.54 ± 0.15 mm) (p 0.004). There was no difference in the level of hs-CRP according to the presence or absence of clinical manifestations. However, it was significantly higher in those with positive DNA (5.71 ± 4.36 mg/L) compared to those with negative results (3.12 ± 1.97 mg/L) (p 0.009). There was a significant correlation of the hs-CRP level with the IMT (r 0.49, p 0.001) and SLEDAI (r 0.67, p < 0.001).ConclusionsThese findings suggest that SLE patients without traditional major cardiovascular risk factors may have increased risk of future cardiac events. Measuring hs-CRP may be useful as a marker of disease activity, increased IMT and subclinical atherosclerosis in SLE especially those with positive ds-DNA.     

Cardiac sarcoidosis mimicking arrhythmogenic right ventricular dysplasia with high defibrillation threshold requiring subcutaneous shocking coil implantation

Cardiac involvement in patients with sarcoidosis has been reported in up to 25-39% of patients and is responsible for up to 85% of deaths attributed to the disease, often due to sudden cardiac death. An established diagnosis of cardiac sarcoidosis (CS) portends an ominous prognosis, with an estimated five year-survival of 44%. We report a case that was initially diagnosed as arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C), but extra-cardiac biopsies later on were consistent with sarcoidosis and a final diagnosis of CS was made. The patient received an implantable cardioverter defibrillator (ICD) with a subcutaneous lead array implant for high defibrillation threshold (DFT). Exclusive right ventricular (RV) involvement is atypical for CS. The predominant RV involvement based on echocardiogram, cardiac magnetic resonance imaging (MRI) and right precordial electrocardiogram changes can lead to misdiagnosis as ARVD/C based on the modified task force criteria. Cardiac sarcoidosis is an under-diagnosed disease and the delay in its diagnosis and appropriate therapy can lead to a fatal outcome. High defibrillation thresholds have not been previously reported in patients with CS, but given the natural progression of the disease and the limitations in current pharmacotherapy, implanters who diagnose and treat such patients must be prepared to deal with this issue.