2. DENTAL CALCULUS
Consists of mineralized bacterial plaque that
forms on the surfaces of natural teeth and
dental prostheses
3. SUPRA GINGIVAL CALCULUS
Located coronal to the gingival margin
Usually white or whitish yellow in color
Hard with clay like consistency
Locations :
Buccal surfaces of maxillary molars
Lingual surfaces of mandibular anterior teeth
6. COMPOSITION
INORGANIC CONTENT : 70-90%
CALCIUM PHOSPHATE– 75.9%
CALCIUM CORBONATE– 3.1%
TRACES OF MAGNESIUM PHOSPHATE
TWO THIRDS OF THE INORGANIC COMPONENT IS
CRYSTALLINE IN STRUCTURE
THE FOUR MAIN CRYSTAL FORMS ARE
HYDROXYAPETITE—58%
MAGNESIUM WHITELOCKITE– 21%
OCTACALCIUM PHOSPHATE—12%
BRUSHITE—9%
8. ATTACHMENT TO THE TOOTH SURFACE
FOUR MODES
Organic pellicle
Mechanical locking into surface irregularities
such as resorption lacunae and caries
Close adaptation of calculus undersurface
depressions to the gently sloping mounds of
the unaltered cementum surface
Penetration of calculus bacteria into cementum
10. FORMATION
Calculus is dental plaque that has undergone
mineralization
The soft plaque is hardened by the
precipitation of mineral salts, which usually
starts between the 1st and 14th days of
plaque formation
11. Calcification occur in 4 - 8 hours which
become
-- 50% mineralized in 2 days and
-- 60% to 90% mineralized in 12 days
12. Saliva is the source of mineralization for
supragingival calculus
Gingival crevicular fluid furnishes the
minerals for subgingival calculus
13. Heavy calculus formers contains
-- more calcium
-- three times more phosphorus and
-- less potassium than
that of non-calculus formers
14. MINERALIZATION OF CALCULUS — THEORIES
TWO PRINCIPALS
1 MINERAL PRECIPITATION
brought about in several ways
A rise in the PH of the saliva causes
precipitation of calcium phosphate salts by
lowering the precipitation constant
15. Colloidal proteins in saliva bind calcium and
phosphate ions and maintain a supersaturated
solution with respect to calcium phosphate salts
16. Phosphate liberated from dental plaque
desquamated epithelial cells or bacteria
precipitate calcium phosphate by hydrolyzing
organic phosphate in saliva thus increasing
the concentration of free phosphate ions
17. 2 SEEDING AGENTS induce
Small foci of calcification that enlarge and
coalesce to form a calcified
mass
This concept has been referred to as the
“epitactic concept” or “heterogenous nucleation”
The corbohydrate –protein complexes may
initiate calcification by removing calcium
from the saliva [chelation] and binding it
to form nuclei that induce subsequent
18. ETIOLOGICAL SIGNIFICANCE
Non-mineralized plaque on the calculus
surface is the principal irritant, but the
underlying calcified portion may be a
significant contributing factor
Subgingival calculus may be the product
rather than cause of periodontal pockets
19. Bacterial plaque that coats the teeth is the
main etiological factor in the development
of periodontal
disease
The removal of subgingival plaque and
calculus constitute the corner stone of
periodontal therapy
21. PREDISPOSING FACTORS
1 IATROGENIC FACTORS
Deficiencies in the quality of
-- dental restorations
-- prostheses
Inadequate dental procedures
Contribute to detoriation of periodontal tissues
24. 4 HABITS AND SELF–INFLICTED INJURIES
Improper tooth brushing
Wedging of toothpicks between the teeth
Fingernail pressure against the gingiva
Pizza burns
Chemical irritation include
-- topical applications of caustic medications
such as aspirin or
cocaine
-- allergic reactions to toothpaste and
chewing gum
-- use of chewing tobacco and concentrated
mouthrinses
