Centrifugal analysis for serum iron and iron-binding capacity using the IL Multistat III Analyzer.

A colorimetric method for the determination of serum iron and total iron-binding capacity (TIBC) has been adapted to an IL Multistat III Centrifugal Analyzer. The correlation to an ESA Ferrochem, Model 3050, which measures iron by coulometry, is acceptable (IL Multistat = 1.08 ESA--5.05). The intra-run precision gave an average C.V. of less than 5%. The day-to-day precision was between 2% and 7% and the average analytical recovery was 102%. This method requires only 150 microliters of sample for both iron and TIBC which is a significant advantage over many existing methods in terms of sample volume, especially when a pediatric population is considered. Both iron and TIBC may be analyzed at the same time on the same rotor. The approximate analysis time is 30 minutes for seven iron and TIBC samples, four controls and one standard. The cost is low, being approximately $0.08 per iron assay and $0.83 per TIBC assay.

Effects of restorative and adhesive curing methods on dentin bond strengths.

PURPOSE: To evaluate the shear bond strengths of "one-bottle" adhesives to dentin when used with self-cured composite. MATERIALS AND METHODS: 100 bovine teeth were ground to expose superficial dentin, which was polished to 600-grit. The dentin was etched for 15 s with 35% phosphoric acid, rinsed, and blotted with tissue paper. The surface remained visibly moist for all specimens. The following adhesives were applied to the etched dentin according to manufacturers' directions: Scotchbond Multi-Purpose (in its visible light-cured [VLC] and self-cure modes) as a control, One-Step (VLC only), OptiBond Solo Plus (VLC only), Prime & Bond NT (VLC) and Prime & Bond NT Dual-Cure. For each adhesive, specimens were bonded with a self-cure composite, while 10 were bonded with a VLC composite as a control. After 24 hrs water storage, shear bond strengths were determined using an Instron universal testing machine. Data were analyzed using two-way ANOVA, Tukey's test, and Student's t-tests. RESULTS: Using the light-cured composite, mean bond strengths ranged from 11.0 MPa for light-cured Prime & Bond NT to 26.3 MPa for OptiBond Solo Plus. Using the self-cure composite, mean bond strengths ranged from 0.0 for light-cured Prime & Bond NT to 21.4 MPa for One-Step. Two adhesives, light-cured Prime & Bond NT and OptiBond Solo Plus, had significantly lower bond strengths when used with the self-cure composite. CLINICAL SIGNIFICANCE: Some "one-bottle" dentin adhesives may not provide acceptable bonding to tooth structure when they are used with self-cure composites.