Possible Clues:

• It's used to sharpen edged tools and knives
• Many modern-day ____s are made of carborundum
• Sweet 'n' hot? (anag)
• Eccentric owns teeth sharpener
• For sharpening edged tools or knives
• Something for sharpening false teeth, shown leaving hospital
• Ethos went sloppy — one should get things sharpened up
• Sharpener
• Bridge designer lacking a thing that could give the edge
• It gives an edge to the news broadcast