Processes contributing to the formation of dental calculus

Abstract

Dental calculus is a petrified plaque biofilm. Calculus removal requires professional scaling procedures as a result of its physical hardness and strong attachment to the teeth. The aim of this paper is to review chemical (MD, Ca, P, F), physical (hardness, adhesive strength), ultrastructural (SEM, TEM), and clinical data on calculus in order to provide perspective on the roles that adhesion and cementation play in tartar development. SEM, TEM and microradiographic analyses of deposits in cross section show that calculus mineralizes in successive layers of varying thickness. Chemical analysis shows that plaque mineralization occurs rapidly (on a clinical time scale, < 2 wks on average) with the formation of calcium phosphate crystals contributing up to 80% of the weight of deposits. Although calculus adheres strongly to the teeth (up to 4,000 kN.m‐2 in attachment force) the hardness measures only 10–20% of sound enamel (20–40 Vickers Hardness Numbers). The clinical formation of calculus (measured as the a...