Dental_Caries_Histopathology_Diagnosis_AAUP_Lecture.pptx

Dental Care

1. Dental Caries: Histopathology, Diagnosis, Arrested, Recurrent, and Root Caries Faculty of Dentistry – Arab American University, Palestine Instructor: Dr. Naji Ziad Arandi Course: Conservative Dentistry III Duration: 60 minutes

2. Learning Objectives By the end of this lecture, students should be able to: 1. Explain microscopic changes in enamel and dentin during caries. 2. Identify clinical and radiographic features of different caries types. 3. Differentiate active, arrested, recurrent, and root caries. 4. Select proper management based on activity and type.

3. Histopathology Overview Histopathology: study of tissue changes during disease. Caries histopathology reveals how enamel and dentin respond to acid attack. Demineralization begins subsurface and spreads inward. [Insert Diagram: Enamel Lesion Zones]

4. Enamel Lesion Zones 1. Translucent zone – first mineral loss 2. Dark zone – early remineralization 3. Body of lesion – greatest loss 4. Surface zone – intact; potential for repair. Surface remains intact allowing remineralization. [Insert Image Placeholder]

5. Dentin Response When caries reaches DEJ, dentin responds: - Sclerotic dentin: mineral fills tubules. - Tertiary dentin: new dentin formation. - Fatty degeneration of odontoblasts. [Insert Histology Image Placeholder]

6. Zones of Dentin Caries 1. Zone of fatty degeneration. 2. Zone of demineralization. 3. Zone of bacterial invasion. 4. Zone of destruction. Only last two zones are infected and must be removed. [Insert Dentin Diagram Placeholder]

7. Infected vs Affected Dentin Infected: Soft, wet, bacteria present, denatured collagen – remove. Affected: Firm, bacteria minimal, collagen intact – preserve.

8. Clinical Implications Histopathology supports minimal intervention. - Fluoride can remineralize early lesions. - Avoid over-excavation. - Preserve affected dentin for pulp vitality.

9. Diagnosis of Caries Diagnosis directs management: - Monitor and remineralize. - Seal and protect. - Excavate and restore. We manage the caries process, not only the cavity.

10. Clinical Examination Dry tooth for 5 seconds—white spots appear. Use adequate light. Avoid forceful probing. Inspect pits, fissures, interproximal, and cervical areas.

11. Caries Activity Assessment Active: rough, matte, chalky, plaque present. Arrested: smooth, shiny, brown/black, plaque-free.

12. ICDAS Scoring 0 – Sound 1–2 – Early enamel change 3–4 – Local breakdown 5–6 – Visible dentin cavity. ICDAS allows standardized caries detection and monitoring.

13. Radiographic Features: Enamel Triangular radiolucency with base at surface. Detected best on bitewings. Requires ~40% demineralization for visibility. [Insert Bitewing Radiograph Placeholder]

14. Radiographic Features: Dentin Spreads laterally along DEJ forming second triangle toward pulp. [Insert Radiograph Placeholder]

15. Diagnostic Adjuncts - DIAGNOdent: laser fluorescence. - Fiber-optic transillumination (FOTI). - Quantitative light fluorescence (QLF). Adjuncts complement, not replace, clinical judgment.

16. Caries Risk Factors - High sugar intake - Poor oral hygiene - Low fluoride exposure - Xerostomia - Orthodontic appliances or defective restorations

17. Diagnostic Pitfalls - Overuse of explorer causing cavitation - Stains mistaken for caries - Radiolucent artifacts mimicking lesions

18. Arrested Caries: Definition Lesion that has stopped progressing. Becomes hard, glossy, inactive. [Insert Photo Placeholder]

19. Clinical Features of Arrested Caries - Brown/black color - Smooth, shiny surface - Often on exposed or self-cleansing areas - Plaque-free.

20. Histopathology of Arrested Caries Reprecipitation of minerals in surface zone. Sclerotic and tertiary dentin formation. Bacteria inactive or absent.

21. Management of Arrested Caries No drilling required. Maintain fluoride exposure. Control plaque. Regular recall appointments.

22. Recurrent Caries Definition New lesion adjacent to an existing restoration. Caused by microleakage, poor adaptation, or residual caries.

23. Etiology of Recurrent Caries - Marginal leakage - Incomplete caries removal - Bond failure - Poor isolation

24. Predisposing Factors - Overhanging margins - Surface roughness - Plaque stagnation - Material degradation

25. Clinical Features of Recurrent Caries - Explorer catches - Marginal softness - Discoloration - Shadowing beneath restoration

26. Radiographic Features of Recurrent Caries Radiolucency beneath restoration. Differentiate from overhangs or voids. [Insert Radiograph Placeholder]

27. Prevention of Recurrent Caries - Rubber dam isolation - Proper adhesive technique - Finishing and polishing margins - Patient hygiene education

28. Management of Recurrent Caries - Small: repair or reseal. - Large: replace restoration. - Address caries risk factors.

29. Root Caries: Definition Soft, progressive lesion on exposed root surfaces involving cementum and dentin. Common in elderly or xerostomic patients.

30. Etiology of Root Caries - Gingival recession - Low salivary flow - Poor hygiene - High carb diet - Aging

31. Clinical Appearance of Root Caries - Yellow to brown, soft surface. - Near CEJ or below gingiva. - Shallow and broad. [Insert Root Caries Photo Placeholder]

32. Histopathology of Root Caries Demineralization of cementum followed by bacterial invasion of dentinal tubules. Possible arrest with sclerosis or tertiary dentin.

33. Diagnosis of Root Caries - Visual-tactile exam - Assess hardness - Radiographs less reliable early on

34. Prevention of Root Caries - Daily fluoride toothpaste and rinse - Professional fluoride varnish - Diet control - Manage xerostomia

35. Management of Root Caries - Non-cavitated: fluoride therapy - Cavitated: restore with GIC or RMGIC. GICs preferred for fluoride release and moisture tolerance.

36. Key Takeaways Caries = biofilm + sugar + time + susceptible surface. Activity, not color, guides treatment. Arrested lesions are healed, not dirty. Recurrent and root caries signal management issues or new risk.

37. Clinical Relevance - Detect early, prevent progression. - Use fluoride and sealants. - Apply minimal intervention philosophy. - Prevention is superior to restoration.

38. Case 1 – White Spot Lesion Photo: white chalky area on smooth surface. Question: Active or arrested? Answer: Active (matte, rough, plaque present).

39. Case 2 – Recurrent Caries Radiograph: radiolucency under restoration. Confirm with explorer. Diagnosis: Recurrent caries.

40. References - Textbook of Operative Dentistry (2015) - Kidd & Fejerskov: Dental Caries: The Disease and Its Clinical Management - Mount & Hume: Preservation and Restoration of Tooth Structure - Featherstone JDB: The caries balance and remineralization