Frank R. Lehmann

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The purpose of this prospective study was to evaluate the clinical outcome of three- to four-unit posterior all-ceramic fixed dental prostheses (FDPs) made of yttria-stabilized tetragonal zirconia-polycrystal ceramic frameworks (CerconBase; Degudent). Fifty-eight restorations were placed in 48 patients. Twenty-four FDPs had an end abutment design (EAD)(More)
OBJECTIVES The purpose of this laboratory study was to evaluate the influence of different surface conditioning, new ceramic primers and cleaning methods on the bond strength of luting resin to zirconia ceramic (e.max ZirCAD). METHODS A total of 96 zirconia ceramic discs were divided into six groups (n=16) according to surface conditioning, cleaning(More)
To evaluate the risk of cancer associated with low and high levels of radon exposure one of the largest single cohort studies on uranium miners is being conducted in Germany including 58,721 men who were employed for at least 6 mo between 1946 and 1989 at the former Wismut uranium company in Eastern Germany. Information on job history, smoking, dust, and(More)
OBJECTIVES The purpose of this in vitro study was the evaluation of the bond strength and its durability of two composite resins to zirconia ceramic after using different surface conditioning methods. METHODS Plexiglas tubes filled with composite resin were bonded to zirconia ceramic discs (Cercon) which were either in their original state as supplied by(More)
The purpose of this study was to evaluate the influence of contamination and subsequent cleaning on the bond strength and durability of an adhesive resin to nano-structured alumina-coated zirconia ceramic. Zirconia ceramic disks were coated with nano-structured alumina, utilizing the hydrolysis of aluminum nitride powder. After immersion in saliva or the(More)
PURPOSE The purpose of this in-vitro study was to evaluate the resin bond strength to pre-etched lithium disilicate ceramic using different cleaning methods after two contamination modes (saliva or saliva and silicone). MATERIALS AND METHODS Plexiglas tubes filled with composite resin (MultiCore Flow) were bonded to etched and silanized ceramic disks made(More)
PURPOSE The purpose of this in vitro study was the evaluation of the bond strength and its durability to zirconia ceramic after using two phosphate monomer-containing primers. MATERIALS AND METHODS Plexiglas tubes filled with composite resin were bonded to zirconia ceramic disks (Cercon) which were air abraded (50 microm Al2O3 at 2.5 bar pressure) and(More)
The aim of this study was to validate oxygen-sensitive 3He-MRI in noninvasive determination of the regional, two- and three-dimensional distribution of oxygen partial pressure. In a gas-filled elastic silicon ventilation bag used as a lung phantom, oxygen sensitive two- and three-dimensional 3He-MRI measurements were performed at different oxygen(More)
OBJECTIVE The purpose of the study was the evaluation of the bond strength of a provisional resin to a polyetheretherketon (PEEK) using different surface treatments and conditioning methods. METHODS PEEK disks were polished with 600grit rotating silicon carbide papers. Plexiglas tubes were filled and bonded with a provisional resin (Luxatemp Fluorescence)(More)