1. Regressive and Traumatic Alterations of Teeth Unit 4

2. Regressive Alteration • Attrition • Abrasion • Erosion

3. Attrition • Physiologic wearing away • Incisal, occlusal and interproximal surfaces • Part of aging process • Bruxism – pathologic attrition

5. Attrition – Radiologic Features • Change in normal outline • Flat occlusal plane • Loss of mamelon • Pulp chamber, canal size • Hypercementosis

6. Attrition

7. Attrition

9. Abrasion • Non-physiologic wearing away • Habits • Toothbrush trauma • Dental floss injury • Occupational hazards

10. Abrasion – Radiologic Features • Radiolucent defects at the cervical region • Well-defined semilunar defects • Pulp chambers sclerosed • In case of dental floss injury, distal surfaces more involved

11. You will write cases today • Describe • Type of film(s) • Location / number of lesions (problem) • Size • Shape • Border • Content • Effects on neighboring structures

12. Case 1 for write-up

13. March 2000 May 2003

14. Erosion • Chemical cause • No bacteria involved • Diet • Regurgitation • Occupational hazards

15. Erosion - Radiologic Features • Radiolucent defects • Dietary acids – labial surface • Regurgitation – mandibular lingual surface • Occupational – all surfaces

18. Resorption Phenomenon • External • Internal

19. External Resorption • Periapical pathology • Trauma • Mechanical forces • Tumors and cysts • Impacted teeth • Osteosclerosis • Idiopathic

20. Ext. Resorption: Periapical Path

21. Ext. Resorption: Trauma

22. Case for Brett Moore

23. Ext. Resorption: Orthodontic

25. Ext. Resorption: Tumors/cysts

26. Ext. Resorption: Tumors/cysts

28. Ext. Resorption:

30. Ext. Resorption: Impacted Tooth

31. Ext. Resorption: Impacted Tooth

32. Ext. Resorption: Osteosclerosis

33. Ext. Resorption: Idiopathic

35. Case for Ruth Atterberg

36. Internal Resorption • Trauma • Idiopathic

37. Int. Resorption: Idiopathic

38. Internal Resorption: Trauma

40. Traumatic Injury to Teeth • Concussion • Luxation • Avulsion

41. Concussion • No displacement or loosening • Crushing injury to adjoining areas • Early radiographic changes may be minimal • Widened PDL spaces: few days to weeks • Long term effects: pulpal sclerosis, necrosis, periapical lesions

42. Luxation • Dislocation of teeth: intrusion, extrusion, lateral, lingual or buccal • Early radiographic observation: widened PDL spaces • Long term effect: pulpal sclerosis, necrosis, periapical lesion

43. Avulsion • Loss of tooth • Socket outline • Fracture of alveolar bone • Possibility of reimplantation

44. Fracture of Teeth • Coronal fracture • Cusp • Pulp • Root fracture • Horizontal • Vertical • (Details of fracture in Unit 11)