title: A microbiological study of dental calculus. I. The microbial flora of mature calculus.
mesh_terms: D001419:Bacteria / Q000302:isolation & purification*; D001431:Bacteriological Techniques; D003728:Dental Calculus / Q000382:microbiology*; D003773:Dental Plaque / Q000382:microbiology; D006801:Humans