Effect of surface roughness and thermal cycling on bond strength of C.P. titanium and Ti-6Al-4V alloy to ceramic

PurposeStudying the effect of surface roughness and thermal cycling on titanium–ceramic bonding.MethodsOne hundred fourteen samples in the form of bar for the C.P. titanium and Ti–6Al–4V alloy were used. They were divided into two groups according to the type of bar. Each group was then subdivided according to the type of surface treatment to three subgroups, control, airborne-particle abrasion and silica coated. Each subgroup was subdivided into two classes according to the type of test (surface roughness and bond strength). Samples used for the bond strength test were veneered. These samples were subdivided into two subclasses according to thermal cycling; whether without thermal cycling or after 6000 thermal cycles.ResultsThe surface roughness test results showed that silica coating recorded the highest surface roughness. Also C.P. titanium gave higher value of surface roughness than Ti–6Al–4V alloy. As regard the bond strength, the airborne-particle abrasion classes and the silica coated classes recorded bond strength values above the acceptable limit of 25 MPa determined in ISO 9693. As regard thermal cycling, the results showed that aging by thermal cycling decreased the metal–ceramic bond strength.ConclusionsThe airborne-particle abrasion and the silica coating are acceptable treatments for titanium–ceramic restorations. Increasing surface roughness of C.P. titanium and Ti–6Al–4V alloy not necessarily results in an increase in their bond strength to ceramics. Aging affects the metal–ceramic bond strength.     

Increased serum level of soluble receptor for advanced glycation end products (sRAGE) in type 2 diabetic patients with nephropathy

Activation of the receptor for advanced glycation end products (RAGE) has been implicated in the development of diabetic vascular complications. Soluble RAGE (sRAGE) could act as a decoy for the RAGE ligands and may thus exert a cytoprotective effect. Since RAGE is upregulated by advanced glycation end products (AGEs), the same could be implied for sRAGE. We aimed to investigate the role of sRAGE as a marker of early diabetic nephropathy. Forty-eight type 2 diabetic patients, further subdivided into group 1 without renal affection (10 patients), group 2 with microalbuminuria (25 patients), and group 3 with proteinuria (13 patients), and age-matched control group 4 (17 subjects) were included. Serum sRAGE, urea, creatinine, plasma glycated hemoglobin (HBA1c), and urinary albumin excretion (albumin/creatinine ratio) were measured. sRAGE levels were significantly higher in groups 2 and 3when compared to groups 1 and 4. No significant difference was found on comparing groups 2 and 3 together or on comparing groups 1 and 4. There was a significant positive correlation between sRAGE level and all the studied parameters (p?<?0.05) as well as a significant association between the sRAGE positivity within the three diabetic groups and the degree of proteinuria. Although sRAGE level was found to be significantly higher in the microalbuminuria group when compared to both the control and diabetics with normal kidney groups, the absolute value did not differ significantly from the proteinuria group. So we say that sRAGE can be used as a marker of diabetic nephropathy; however, its absolute level cannot be used to distinguish different degrees of renal affection.     

Differences in outcomes between cholecalciferol and ergocalciferol supplementation in veterans with inflammatory bowel disease

Aim: Vitamin D deficiency is a global health issue associated with increased health‐care costs, and could play a role in the pathogenesis and management of inflammatory bowel disease. Prior studies show a high prevalence of vitamin D deficiency in veterans with inflammatory bowel disease. We aimed to examine the outcome differences in patients with inflammatory bowel disease, comparing treatment with ergocalciferol to cholecalciferol. Methods: A retrospective review of electronic medical records of patients with inflammatory bowel disease at a Veterans Affairs Medical Facility in the Southeastern United States was carried out. Those with at least one serum 25(OH) vitamin D level were included. Initial and follow‐up vitamin D values were recorded. The type of vitamin D supplementation, whether cholecalciferol or ergocalciferol, was documented. Costs in the year after measurement of vitamin D were divided into separate inpatient and outpatient categories. Results: Veterans (n = 108) with ulcerative colitis or Crohn's disease and an available 25(OH) vitamin D level were studied. There were differences in follow‐up vitamin D levels; those who received weekly ergocalciferol had higher subsequent levels than those who received cholecalciferol, especially at a second follow up, although differences did not achieve statistical significance. However, those who received vitamin D3 were less likely to use laboratory, pharmacy, radiology and fee‐based services, and had lower laboratory and pharmacy costs. Conclusions: Our data suggest that cholecalciferol replacement might improve outcomes to a greater extent than ergocalciferol, and might be better in limiting health‐care costs and expenses in patients with inflammatory bowel disease. Geriatr Gerontol Int 2012; 12: 475–480.