Variations in dental calculi composition and structure.
D000328:Adult; D000368:Aged; D002130:Calcium Phosphates / Q000032:analysis*; D055598:Chemical Phenomena; D002621:Chemistry; D003461:Crystallography; D003728:Dental Calculus; D003804:Dentin / Q000032:analysis*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006882:Hydroxyapatites / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D012463:Saliva / Q000032:analysis
D002130:Calcium Phosphates; D006882:Hydroxyapatites