Prevalence of partial edentulism and RPD design in patients treated at College of Dentistry, Imam Abdulrahman Bin Faisal University, Saudi Arabia.

This study aimed to investigate the prevalence of partial edentulism, RPD type, design, and components and their frequency of use by patients at the prosthodontic clinics of the College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia. The prepared surveys, laboratory authorization forms, and images of the RPD metal frameworks on casts were used for data collection. Two calibrated investigators studied the digital photographs to identify the Kennedy classification, type of RPD, major connector, clasp assembly, and other details. Data was collected and analyzed statistically. The results showed that the most common class of partial edentulism was Kennedy class I, whereas class IV was the least (p < 0.001). Sixty two percent of fabricated RPDs had metal frameworks, whereas 37.2% were frameless. RPI was the most frequently used clasp assembly (38.9%), a significant finding in Kennedy class I(p < 0.01). The maxillary anteroposterior palatal strap and mandibular lingual plate were the most commonly used major connectors, at 41.2% and 60.8%, respectively. Conclusions: Simple RPD design that accomplishes the treatment objectives as well as proper communication with a well-trained dental technician would promote the success of RPDs.

Effect of Nanodiamond Addition on Flexural Strength, Impact Strength, and Surface Roughness of PMMA Denture Base.

PURPOSE: To assess the effect of addition of different concentrations of nanodiamonds (NDs) on flexural strength, impact strength, and surface roughness of heat-polymerized acrylic resin. MATERIALS AND METHODS: 120 specimens were fabricated from heat-polymerized acrylic resin. They were divided into a control group of pure polymethylmethacrylate (PMMA; Major.Base.20) and three tested groups (PMMA-ND) with 0.5%wt, 1%wt, and 1.5%wt of added ND to PMMA. Flexural strength was determined using the three-point bending test. Impact strength was recorded by using a Charpy type impact test. Surface roughness test was performed using a Contour GT machine. One-way ANOVA and Tukey's post-hoc analysis (p ≤ 0.05) were used for statistical analysis. RESULTS: Acrylic resin reinforced with 0.5% ND displayed significantly higher flexural strength than the unreinforced heat-polymerized specimens, acrylic resin reinforced with 1% ND and the 1.5% ND (p < 0.0001). The impact strength of unreinforced heat-polymerized specimens was significantly higher than all nano-composite materials (p < 0.0001) with no significant difference between 1% ND and the 1.5% ND (p > 0.05). The addition of 0.5% ND and 1% ND significantly decreased the surface roughness in comparison to both control and the 1.5% ND groups (p < 0.0001) while no significant differences between 0.5% ND and 1% ND (p > 0.05) were reported. Nano-composite material (0.5% ND) showed significantly lower surface roughness when compared to other specimens. CONCLUSIONS: The addition of NDs to acrylic denture base improved the flexural strength and surface roughness at low concentrations (0.5%), while the impact strength was decreased with ND addition.

Takotsubo cardiomyopathy complicating thoracoabdominal aortic aneurysm repair.

We describe the management of a patient with symptomatic spinal cord hypoperfusion after thoracoabdominal aortic aneurysm repair, where the neurological insult and associated emotional stress precipitated Takotsubo cardiomyopathy. Transthoracic Echocardiography showed akinetic mid and apical left ventricular segments, while basal segments were spared. Emergent coronary angiography ruled out acute coronary syndrome. Excess catecholamines have been postulated as a contributing mechanism to the disease, therefore, catecholamines were avoided to prevent further myocardial injury. Takotsubo cardiomyopathy is associated with serious morbidity and mortality, which highlights the importance of early recognition and proper management for complete recovery of both cardiac and neurologic functions.

The Reinforcement Effect of Nano-Zirconia on the Transverse Strength of Repaired Acrylic Denture Base.

Objective. The aim of this study was to evaluate the effect of incorporation of glass fiber, zirconia, and nano-zirconia on the transverse strength of repaired denture base. Materials and Methods. Eighty specimens of heat polymerized acrylic resin were prepared and randomly divided into eight groups (n = 10): one intact group (control) and seven repaired groups. One group was repaired with autopolymerized resin while the other six groups were repaired using autopolymerized resin reinforced with 2 wt% or 5 wt% glass fiber, zirconia, or nano-zirconia particles. A three-point bending test was used to measure the transverse strength. The results were analyzed using SPSS and repeated measure ANOVA and post hoc least significance (LSD) test (P ≤ 0.05). Results. Among repaired groups it was found that autopolymerized resin reinforced with 2 or 5 wt% nano-zirconia showed the highest transverse strength (P ≤ 0.05). Repairs with autopolymerized acrylic resin reinforced with 5 wt% zirconia showed the lowest transverse strength value. There was no significant difference between the groups repaired with repair resin without reinforcement, 2 wt% zirconia, and glass fiber reinforced resin. Conclusion. Reinforcing of repair material with nano-zirconia may significantly improve the transverse strength of some fractured denture base polymers.

Open aortic repair after prior thoracic endovascular aortic repair.

BACKGROUND: Thoracic endovascular aortic repair (TEVAR) has been applied to increasingly complex aortic pathology, resulting in an increase in late complications. We characterized patients undergoing open repair after prior TEVAR including indications, operative techniques, and outcomes. METHODS: Chart review and query of a prospectively collected database identified 50 patients who underwent thoracic aortic operation after prior TEVAR. Active follow-up was supplemented by Social Security information for vital status. RESULTS: From July 2001 to January 2012 open arch (n = 25), descending (n = 6), thoracoabdominal (n = 17), or extra-anatomic bypass (n = 2) operations were performed after previous TEVAR (median interval from TEVAR to open surgical procedure: 13.9 months; interquartile range, 0.5 to 24 months). Indications for open operation included type 1 endoleaks (n = 19), retrograde aortic dissection (n = 9), chronic aortic dissection with persistent growth of the false lumen (n = 16), and graft infection (n = 6). Sixty percent had prior cardiovascular surgical procedures and 18% were done as emergencies. Circulatory support was required in 78% and hypothermic arrest in 48%. Hospital mortality occurred in 3 (6%) patients with no strokes and 1 patient with myocardial infarction; 5 (10%) patients required tracheostomy and 1 required dialysis. Survival was 67% at a median follow-up of 2.9 years. CONCLUSIONS: Conversion to open repair after thoracic stent-grafting may be indicated for type 1 endoleak, retrograde dissection, chronic aortic dissection with persistent false lumen growth, or graft infection. These salvage operations are complex but can be completed safely with good early outcomes and preservation of the stent-graft in most cases. Late outcomes are consistent with the chronic disease state of these patients.