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Melamine formaldehyde microcapsules containing octadecane are synthesized by the interfacial polymerization method, and the size, shape, and thermal storage/release prop erties of the synthesized microcapsules are analyzed by FTIR, SEM, and DSC. Polyester fabrics are then coated with the microcapsules under various conditions of concentration and time/temperature by the knife-over-roll (KOR) and screen printing (SP) methods. The thermal, mechanical, and physical properties of the untreated and treated fabrics are evaluated to identify the best adhesive method. The mean diameter of the microcapsules ranges from 1 to 1.5 μm, and their shapes are almost spherical. Under the optimum treatment concentration, temperature, and time, thermal properties after five launderings decrease rapidly, and the bending and shear rigidities of the KOR fabrics are higher than those of the sp fabrics. This means that fabrics coated by sp become less stiff and hard than those by KOR. sp fabrics exhibit higher air permeability and lower hygroscopic properties than KOR fabrics.

Although several techniques have been proposed to remove fiber-reinforced composite (FRC) post, no safe and efficient technique has been established. Recently, a guided endodontics technique has been introduced in cases of pulp canal obliteration. This study describes 2 cases of FRC post removal from maxillary anterior teeth using this guided endodontics technique with a dental operating microscope. Optically scanned data set from plaster cast model was superimposed with the data set of cone-beam computed tomography. By implant planning software, the path of a guide drill was selected. Based on them, a customized stent was fabricated and utilized to remove the FRC post. Employing guided endodontics, the FRC post was removed quickly and safely with minimizing the loss of the remaining tooth structure. The guided endodontics was a useful option for FRC post removal.

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The polymeric micelles from amphiphilic block copolymer poly(vinyl alcohol-b-styrene) (poly(VA-b-St)) with different syndiotacticity of poly(vinyl alcohol) (PVA) block were prepared by dialysis against water. Critical micelle concentration (CMC) and dynamic properties of poly(VA-b-St) copolymeric micelles were investigated by fluorescence techniques. From the fluorescence emission spectrum measurements using pyrene as a fluorescence probe, the observed CMC value was in the range of 0.125-4.47 mg/L. The CMC value increased with decreasing the weight ratio of PS to PVA block and with increasing the syndiotacticity of PVA block. The rate of pyrene release was very slow for block copolymers containing PVA block with higher syndiotacticity, which indicates that their micelles have increased kinetic stability.