This document discusses dental calculus, which is a hard mineral deposit that forms on teeth and dental prosthetics from mineralized dental plaque. It describes two types of calculus: supragingival calculus above the gums and subgingival calculus below the gums. Calculus forms from inorganic and organic components and attaches to teeth in various ways. The formation of calculus occurs as dental plaque mineralizes over time, reaching maximum levels within 10 weeks to 6 months before declining. Several theories are presented for the mineralization process of calculus, with the accepted theory being precipitation of calcium phosphate salts as pH increases due to loss of carbon dioxide and ammonia formation.

1. Good
Afternoon
Folks
Good
Afternoon
Folks

2. Calculus
Dr. Abhishek Gaur
BDS, MDS, FAGE, Ph. D. (Forensic Sciences)
Department of Periodontics
Raj Rajeshwari Dental College & Hospital
Umarda, Udaipur (RAJ.)

5. Calculus is a hard deposit that is formed by mineralization of dental plaque on the
surfaces of natural teeth and dental prosthesis, generally covered by a layer of
unmineralized plaque.
Types :
1. Supra-gingival Calculus
It is the tightly adherent calcified deposit that forms on the clinical crowns of the
teeth above the free gingival margin. Hence, it is clinically visible.
It is also called as salivary calculus because it forms from the saliva.
2. Sub-gingival Calculus
As the name implies, it is that calcified deposits that is formed on the root surfaces
below the free marginal gingiva.
It is believed to be formed from the gingival exudate and hence called serial
calculus.
It consists of :
a. Inorganic components
b. Organic Components

9. Attachment to the tooth
Surface
4 types :
1. Attachment by means of an Organic Pellicle.
2. Mechanical interlocking into surface irregularities such
as resorption lacunae and Caries.
3. Penetration of calculus bacteria into Cementum.
4. Close adaptation of calculus under surface depressions to
the gently sloping mounds of the unaltered cementum
surface.

10. Formation
Calculus is Nothing but, dental plaque
that has undergone Mineralization.
Formed by precipitation of mineral
salts, which can start between 1st &
14th day of plaque formation.
In 2 days plaque can be 50 %
mineralised, and 60 - 90 % gets
mineralisation in 12 days.

11. Calculus formation continues until it reaches
Maximum levels in about 10 weeks & 6 months,
and after which there is a decline in it’s formation,
due to mechanical wear from food and from the
lips, cheeks & tongue.
T h i s d e c l i n e i s r e f e r r e d t o a s
Reversal Phenomenon.

12. Theories related to Mineralization
of
Dental Calculus
Booster / Precipitation Theory
Loss of CO2 & formation of ammonia leads to
increase in the pH which leads to the
precipitation of calcium phosphate salts.
_Accepted Theory_
Theories related to Mineralization
of
Dental Calculus

13. Epitactic / Nucleation Concept :
Seeding agents induce small foci of
calcification that enlarge & unite together to
form calcified mass.
Seeding agents : Carbohydrates - Protein
complexes.
(removing Calcium from saliva & binding
with it to form nuclei that induce deposition
of minerals)

14. Inhibition Theory
Sites : Calcifying & Non-Calcifying
Inhibiting Substance : Pyrophosphate
Controlling Enzyme : Alkaline Pyrophosphate
(Hydrolyze the pyrophosphate to phosphate )
Mechanism : Calcification only occurs at specific sites
because of the existence of inhibiting mechanism at non-
calcifying sites.
The pyrophosphate inhibits calcification by preventing the
initial nucleus from growing, possibly by “Poison” the
growth centres of the Crystals.

15. …Thank You……Thank You…