Abstract
The inorganic chemical and crystallographic composition of seventy-three dental calculus samples of known origin has been investigated. The findings showed the average ash content to be 77%. Calcium, phosphorus, magnesium, fluoride and carbon dioxide averaged 34, 19, 0.9, 0.05 and 1.8% respectively on an ash weight basis. Significantly higher amounts of magnesium were found in subgingival calculus (1.2%) and posterior supragingival calculus (0.9%) than in anterior supragingival calculus (0.7%). Fluoride was higher in subgingival samples (0.08%) than in supragingival samples (0.03 %). Carbon dioxide was lower in posterior supragingival samples (1.3%) than in other samples (1.9%). X-ray crystallographic findings showed hydroxyapatite, whitlockite and octacalcium phosphate to occur in more than 80% of the samples, each accounting for approximately one third of the mineral phase. Brushite occurred infrequently and only in small amounts. Apatite was found least frequently in posterior supragingival calculus. Whitlockite was most abundant in subgnigival calculus, while octacalcium phosphate was found most abundant in supragingival posterior samples. A significant positive correlation ( r = 0.76) was observed between the magnesium content of the calculus and the whitlockite abundance. The carbon dioxide content showed positive correlation ( r = 0.52) with apatite abundance. The fluoride concentration did not appear related to any crystalline phase.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
