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Dental Calculus - Formation, Pathogenesis and Removal
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- 2. Dental calculus isdefined as the calcified or calcifying deposits that are found attached to the surfaces of teeth and other solid structures in the oral cavity (Lindhe J, 1990). DEFINITION
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- 4. • Supragingival calculuscommonly develops in two locations: • Buccal surfaces of the maxillary molars. • Lingual surfaces of the mandibular anterior teeth •Parotid gland: •Saliva flows over the upper molars via Stensen's duct. •Submaxillary and sublingual glands: •Saliva empties onto the lingual surfaces of the lower incisors via Wharton's duct and Bartholin's duct.
- 5. Subgingival calculus: Located belowthe crest of the marginal gingiva. Not visible during routine clinical examination. Evaluation: Assessed through careful tactile perception using an explorer.
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- 8. COMPOSITION INORGANIC CONTENT Inorganic contentin supragingival calculus: • Composed of 70%-90% inorganic components. • Main compounds: • Calcium phosphate (75.9%) • Calcium carbonate (3.1%) • Magnesium phosphate (traces) • Traces of other metals
- 9. Comparison with othercalcified tissues: Similar percentage of inorganic constituents. Principal inorganic elements: • Calcium: 39% • Phosphorus: 19% • Carbon dioxide: 1.9% • Magnesium: 0.8%
- 10. ORGANIC CONTENT • Brushite(9%) •Octacalcium phosphate(12%) • Magnesium containing whitlockite(21%) • Hydroxyapatite(58%).
- 11. CALCULUS FORMATION • Calculusis dental plaque that has undergone mineralization. • The soft plaque is hardened by the precipitation of mineral salts (between the 1st and 14th day of plaque formation). • Calcification occurs in 4 to 8 hours.
- 12. • Calcifying Plaques: •Can become mineralized in 2 to 12 days. • Supragingival calculus mineralizes from saliva. • Subgingival calculus mineralizes from gingival crevicular fluid (serum). • Calcium Concentration: • Plaque can concentrate calcium at 2 to 20 times its level in saliva. • Calcification Process: • Begins along the inner surface of supragingival plaque. • Also starts in the attached component of subgingival plaque near the tooth. • Separate calcification foci grow and merge to form solid calculus masses. • Calcification may lead to changes in the bacterial content of plaque.
- 13. • Variability inCalculus Formation: • Initiation of calcification and rate of accumulation vary: • Between different individuals. • Between different teeth. • At different times in the same person. • Classification of Calculus Formers: • Individuals can be classified as: • Heavy calculus formers. • Moderate calculus formers. • Slight calculus formers. • Non-calculus formers. • Maximum Calculus Formation: • Calculus formation continues until it reaches a maximum level. • After reaching the maximum, the amount may decrease. • The time to reach the maximum level ranges from 10 weeks to 6 months.
- 14. THEORIES REGARDING THEMINERALIZATION OF CALCULUS 1. MINERAL PRECIPITATION RESULTS FROM A LOCAL RISE IN THE DEGREE OF SATURATION OF CALCIUM AND PHOSPHATE IONS, which maybe brought about in several ways: • Increased pH in Saliva: • Causes calcium phosphate salts to precipitate by lowering the precipitation constant. • pH can rise due to: • Loss of carbon dioxide. • Ammonia production by plaque bacteria. • Protein degradation during saliva stagnation.
- 15. • Role ofColloidal Proteins: • Colloidal proteins in saliva bind calcium and phosphate ions. • When saliva stagnates: • Colloids settle out. • The supersaturated state is disrupted. • This leads to the precipitation of calcium phosphate salts.
- 16. 2. SEEDING AGENTSINDUCE SMALL FOCI O F CALCIFICATION THAT ENLARGE AND COALESCE TO FORM A CALCIFIED MASS. • Epitactic Concept / Heterogeneous Nucleation: • This concept suggests that seeding agents help initiate calculus formation. • The exact seeding agents are unknown, but the intercellular matrix of plaque is believed to play a key role.
- 17. 1. Attachment viaOrganic Pellicle: • Calculus attaches to the tooth surface through an organic pellicle (a thin protein layer). 2. Mechanical Locking into Surface Irregularities: Calculus can mechanically lock into: • Resorption lacunae (small pits or holes in the tooth surface). • Caries (decayed areas). ATTACHMENT OF CALCULUS Four modes of attachment have been described :
- 18. 3.Close Adaptation toCementum Surface: • The undersurface of calculus adapts closely to: • Gently sloping mounds of unaltered cementum. 4.Bacterial Penetration into Cementum: • Calculus bacteria can penetrate into cementum. • When deeply embedded, calculus may resemble cementum and is termed calculocementum
- 19. ROLE OF SALIVA •Supragingival Calculus Formation (Initial Stages): • Selective Adsorption of Salivary Proteins: Salivary proteins are selectively adsorbed onto the tooth surface. • Formation of Pellicle: These proteins form an organic pellicle. • Bacterial Attachment and Colonization: Bacteria attach to and colonize the pellicle. • Role of Saliva: • Both parotid saliva and submandibular saliva are supersaturated with CaPO (calcium phosphate) ₄ . • This supersaturation contributes to the mineralization process of calculus.
- 20. • Role ofUrea in Plaque: • Saliva contains an abundant supply of urea. • Urea promotes base (alkaline) formation in plaque, which enhances CaPO (calcium phosphate) precipitation ₄ . • Susceptible Areas for Calculus Formation: • Lower anterior lingual (inside of lower front teeth) and upper posterior buccal (outside of upper back teeth) regions are prone to calculus formation. • This is due to the low sucrose concentration in saliva in these areas.
- 21. DETECTION OF DENTALCALCULUS I. Appearance and Consistency Appointment planning, selection of instruments, and techniques depend on understanding the texture, morphology, and mode of attachment of calculus.
- 22. • II. SupragingivalExamination • A. Direct Examination: • Supragingival deposits (calculus) can be seen: • Directly by visual inspection. • Indirectly using a mouth mirror. • B. Use of Compressed Air: • Small amounts of calculus may be invisible when wet with saliva. • By using light and drying with compressed air, small deposits can usually be made visible.
- 23. III. Subgingival Examination •A. Visual Examination: • Dark Edge of Calculus: • A dark edge of calculus may be visible at or just below the gingival margin. • Gentle Air Blast: • Using a gentle air blast can deflect the gingival margin away from the tooth, making calculus easier to see. • Transillumination: • A dark, opaque, shadow-like area on a proximal tooth surface may indicate subgingival calculus. • Without calculus, stain, or thick soft deposits, the enamel appears translucent. • B. Gingival Tissue Color Change: • Dark calculus may reflect through a thin gingival margin, suggesting the presence of subgingival calculus.
- 24. • C. TactileExamination 1. Probe: • While assessing sulcus or pocket characteristics, a rough subgingival tooth surface can be felt if calculus is present. 2. Explorer: • A fine subgingival explorer is required to: • Adapt closely to the root surface. • Reach the bottom of the pocket to detect calculus.
- 25. D. Radiographic Examination: •Thick, highly mineralized calculus may be visible on proximal tooth surfaces in radiographs. E. Perioscopy: • A dental endoscope can be used in deep pockets and furcation areas to detect calculus that is otherwise undetectable, especially burnished calculus.
- 26. DENTAL CALCULUS ANDPERIODONTAL DISEASE • Bacterial Content of Calculus: • Calculus itself contains few viable bacteria. • However, it is almost always covered by dental plaque, which contains periodontal pathogens. • Porosity of Calculus: • Calculus is a porous substrate, similar to dentin and cementum. • It can adsorb various substances from: • Saliva. • Gingival exudate. • Examples of adsorbed substances include: • Fluoride. • Bacterial by-products.
- 27. CONCLUSION • Dental Calculus: •Represents mineralized bacterial plaque. • Always covered by unmineralized, viable bacterial plaque. • Role in Periodontitis: • Calculus is a secondary etiologic factor for periodontitis. • Its presence: • Makes adequate plaque removal impossible. • Prevents patients from performing proper plaque control. • Plaque Retention: • Calculus is the most prominent plaque-retentive factor. • Its removal is essential as a foundation for effective periodontal therapy and preventive care.