dental calculus Flashcards
what is the definition of dental calculus?
Mineralized plaque that forms on the surfaces of natural teeth and dental prostheses
what are the 2 types of calculus?
1) supragingival
2) subgingival
characteristics of supragingival plaque
Coronal to gingival margin White/whitish yellow Clay-like consistency Easily detached from tooth surface Commonly found opposite salivary ducts
characteristics of subgingival plaque
Below gingival margin
Hard, dense
Dark colored
Extend to base of pocket, but does not reach JE
With gingival recession, subgingival becomes supragingival
how can dental calculus be detected?
tactile exploration
dental radiographs (not always)
a blast of air to open gingival margin
Color of the overlying gingiva
T/F: Calculus represents a primary cause of periodontitis.
FALSE
Calculus represents a secondary product of infection and not a primary cause of periodontitis.
Clinically, subgingival calculus is most frequently diagnosed using what method?
Tactile exploration
the ______ calcifies and attaches to cementum, enamel or dentin
Pellicle
what types of surface irregularities can calculus attach to?
Caries
Exposed root cementum
Previous insertion of Sharpey’s fibres
Root resorption
this form of calcium phosphate is the basis for supragingival calculus formation, and is Seen in recent (<2 week old) calculus
CaH(PO4) x 2 H2O= Brushite (B)
Ca4H(PO4)3 x2H2O= Octa calcium phosphate (OCP)
Predominant in exterior layers
Forms platelet like crystals
this form of calcium phosphate is:
Predominant in inner layers of old calculus
Forms rod or sand-grain like crystals
Ca5 (PO4)3 xOH= Hydroxyapatite (HA)
where is Whitlockite (W) mostly found? what is its crystal shape?
Most common form in subgingival calculus
Hexagonal crystals
T/F: Roughness of calculus DOES NOT initiate gingivitis
true
why is calculus removed?
Calculus is removed due to its plaque retentive nature
