Regressive alterations of teeth

Regressive alterations

1. REGRESSIVE ALTERATIONS OF TEETH NON-CARIOUS LESIONS OF TEETH Dr VASANTHI V Senior Lecturer, Dept of Oral Pathology

2. Attrition Mechanical wear of tooth Incisal / Occlusal /Proximal surface Tooth to tooth contact Age –dependent Usually physiologic Permanent > Primary Circular/Oval facets –tip of cusp Latin verb - Attritum – rubbing against

3. Types - Attrition

4. Predisposing factors - Attrition

5. Clinical manifestations - Attrition

6. Abrasion Pathologic wearing of tooth Frictional force between tooth & external object Abnormal mechanical process Exposed root surfaces/ incisal surface Improper brushing habits Abrasive dentrifice Left quadrant- right handed Occupation – carpenter, tailor, shoe maker Habits – pipe smokers Improper use of tooth pick, dental floss Latin verb - Abrasum – to scrape off

7. Erosion Saliva- buffering capacity, pH, SFR Non bacterial chemical process Erosum - to corrode Dissolution of mineralised tooth structure Acids – Intrinsic/Extrinsic Perimolysis

8. Risk factors - Erosion

9. Extrinsic causes Acidic foods Beverages Medicaments Environmental acids Intrinsic causes GERD, Bulimia nervosa, Salivary gland hypofunction Increased abdominal pressure Increased acid production Inappropriate relaxation of lower sphincture Vomiting – alcoholism, gastritis, pregnancy, nervous disorders

10. Abfraction Pathologic loss of tooth substance Biomechanical loading Flexure of enamel/dentin at a location away from loading Stress concentration at cervical areas of teeth Cervical region Wedge shaped Sharp internal/external line angles Latin word- Ab away, fractio breaking To break away

11. ABRASION ABFRACTION Saucer shaped worn areas V-Shaped notches Improper brushing/Foreign substance From clenching/grinding (Stress induced) Associated with recession Extend below gum line Canines & Premolars Single teeth with eccentric occlusal loads

12. DENTINAL SCLEROSIS Transparent Dentin Sclerosis of primary dentin Calcification of dentinal tubules Caries/abrasion Aging Translucent zone Difference in refractive index Source of calcium- fluid/dental lymph in tubules Slows carious process Decreased odontoblastic conductivity Harder, highly calcified than normal dentin

13. DEAD TRACTS Optical phenomenon Ground section Transmitted light- black Reflected light – white Difference in refractive index Retraction/degeneration of odontoblastic processes Death of odontoblasts Empty tubules/air filled Dental caries Attrition Abrasion Erosion Cavity preparation Initial step - Sclerotic dentin

14. SECONDARY DENTIN After root completion Normal/abnormal stimulus Irregular dentinal tubules Less calcium, phosphorus Less mineralised Physiologic secondary dentin Reparative/tertiary dentin Decreased tooth sensitivity Anterior > Posterior Pulp horn/proximal walls Decrease in size of pulp chamber/root canal Resting line, fewer tubules Osteodentin

15. PULP STONES Age Microorganisms?? Dental procedures??? Denticles /Diffuse calcifications True/false denticles Free/attached denticles Pain Mild neuralgia to excruciating pain?? Purely coincidental finding Difficult pulp extirpation

16. HYPERCEMENTOSIS Cementum hyperplasia Excessive deposition of cementum Non- neoplastic Isolated/generalised Entire root/only apex Idiopathic/local/systemic Etiology – Accelerated elongation of tooth Inflammation at apex Tooth repair Paget’s Disease Calcified thrombosed vessels of PDL

17. CEMENTICLES Small foci of calcified tissue – Periodontal ligament Regenerative change Dystrophic calcification Single/multiple Free/attached Etiology – Degenerative Calcification of epithelial rests Calcified sharpey’s bundles Cemental tears Calcified thrombosed vessels of PDL Calcium salts - connective tissue Union- Cementum /Alveolar bone Circular Lamellated structure