Richard L. Clarke

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OBJECTIVES The aims of the study were to process a ceramic material with a fine leucite particle size using hot pressing techniques, to increase the flexural strength, reliability and ease of use. METHODS A starting glass composition of wt%; 64.2% SiO(2), 16.1% Al(2)O(3), 10.9% K(2)O, 4.3% Na(2)O, 1.7% CaO, 0.5% LiO and 0.4% TiO(2) was used to produce a(More)
OBJECTIVES The aims of the study were to test and compare the biaxial flexural strength and reliability of Empress 2 ceramics after heat treatment and the addition of the veneering material and to characterise their microstructures. METHODS Forty disc specimens (2 x 14 mm) and forty disc specimens (1 x 14 mm) were produced by heat pressing in the EP 500(More)
OBJECTIVES The aims of the study were to explore the nucleation and crystallization kinetics of an aluminosilicate glass in K2O-Al2O3-SiO2 system and to characterize it. OBJECTIVES A starting glass composition of wt%; 64.2% SiO2, 16.1% Al2O3, 10.9% K2O, 4.3% Na2O, 1.7% CaO, 0.5% LiO and 0.4% TiO2 was heated in an electric furnace and later quenched to(More)
The biaxial flexural strength of Optimal pressable ceramics and IPS Empress pressable ceramics were tested, compared and the micro-structures and compositions explored. The materials evaluated were Optimal shaded (Opcs) and unshaded (Opcus) ceramics and IPS Empress shaded (Ems) and unshaded (Emus) ceramics. Twenty-one disc specimens per material were(More)
This article explores the role of electronic data interchange (EDI) in retail supply-chain management. The benefits that EDI can offer retailers in assisting them in supply-chain management activities is highlighted. Then, the history and development of EDI over the years, as well as current practices, are reviewed. The article finally addresses the(More)
Financial transparency is based on concepts for valid, standardized information that is readily accessible and routinely disseminated to stakeholders. While Congress and others continuously ask for an accounting of public health investments, transparency remains an ignored concept. The objective of this study was to examine financial transparency practices(More)
OBJECTIVES The flexural strength, reliability and microstructure of a heat pressed ceramic system (Empress) was evaluated in comparison with three current frit materials used in ceramic crown and inlay construction. METHODS Twenty bar specimens per material were constructed, overglazed and transverse tested at a crosshead speed of 0.5 mm/min. Etched and(More)
OBJECTIVES The aims of the study were to develop and test overglaze materials for application to the fit surface of dental ceramic restorations, which could be etched and adhesively bonded and increase the flexural strength of the ceramic substrate. METHODS Three glaze materials were developed using commercial glass powders (P25 and P54, Pemco, Canada).(More)
This review of the published literature on dental materials for the year 1997 has been compiled by the Dental Materials Panel of UK. It continues a series of annual reviews started in 1973. Emphasis has been placed upon publications, which report upon the materials science or clinical performance of the materials. The review has been divided by accepted(More)