Chapter 35: Interpretation of Trauma, Pulpal Lesions, and Periapical lesions

Chapter 35

1. Interpretation of Trauma, Pulpal Lesions, and Periapical Lesions Chapter 35

2. Introduction Purpose To provide a brief overview of the common features of trauma and pulpal and periapical lesions as viewed on dental images

3. Trauma Viewed on Dental Images (Cont.) Trauma Trauma is an injury produced by an external force. It may affect the crowns and roots of teeth as well as alveolar bone. It may result in injuries of teeth and bone and injuries such as intrusion, extrusion, and avulsion.

4. Fractures The breaking of a part May affect the crowns and roots of teeth or the bones of the maxilla or mandible Includes: Crown fractures Root fractures Jaw fractures Whenever a fracture is evident or suspected, image examination of the injured area is necessary.

5. Crown Fractures This most often involves anterior teeth. May involve enamel, dentin, and/or pulp The dental image permits evaluation of the proximity of the damage to the pulp chamber and evaluation of the root for any additional fractures. Most crown fractures result from an accident involving a fall or a motor vehicle.

6. Crown Fractures (Cont.)

7. Root Fractures Root fractures most often occur in the maxillary central region. They may be vertical or horizontal, single or multiple. If the x-ray beam is parallel to the plane of the fracture, it will appear as a radiolucent line. If the x-ray beam is not parallel to the plane of the fracture, it may not be apparent at all. Less common than crown fractures. Result from an accident or traumatic blow. With time, root fractures have a tendency to enlarge because of displacement of root fragments, hemorrhage, or edema.

8. Root Fractures (Cont.)

9. Jaw Fractures Jaw fractures are most often observed in the mandible. The panoramic image is the best film for visualizing mandibular fractures. On a dental image, the fracture appears as a radiolucent line. Frequently result from assaults, accidents, and sports injuries. Maxillary fractures are typically difficult to detect on dental images. Maxillary fractures occur less frequently and most often involve the anterior alveolar bone and teeth.

10. Jaw Fractures (Cont.)

11. Injuries Trauma may result in the displacement of teeth. Displacement involves luxation (intrusion and extrusion) and avulsion. Dental images allow for the evaluation of structures after tooth displacement.

12. Luxation Luxation is the abnormal displacement of teeth. Intrusion is the abnormal displacement of teeth into bone. Extrusion is the abnormal displacement of teeth out of bone. Teeth that have been luxated should be evaluated by a periapical image and examined for root and adjacent alveolar bone fractures, damage to the periodontal ligament, and pulpal problems.

13. Luxation (Cont.)

14. Luxation (Cont.)

15. Dental Avulsion Complete displacement of a tooth from alveolar bone The periapical image shows a tooth socket without a tooth. Result from trauma associated with an assault or accidental fall. Dental images are important in the evaluation of the socket areas and should be used to examine the region for splintered bone.

16. Avulsion

17. Resorption Viewed on Dental Images Physiologic resorption A process seen with the normal shedding of primary teeth The primary tooth is shed when resorption of the roots is complete. Pathologic resorption A regressive alteration of tooth structure observed when a tooth is subjected to abnormal stimuli May be: External resorption Internal resorption

18. Physiologic Resorption - of a mandibular deciduous second molar

19. External Resorption Seen along the periphery of the root surface This is often associated with reimplanted teeth, abnormal mechanical forces, trauma, chronic inflammation, tumors and cysts, impacted teeth, or idiopathic causes. It most often involves the apices of teeth. The apical region appears blunted. The length of the root is shorter than normal. Both the lamina dura and the bone around the blunted apex appear normal. Not detected clinically and does not exhibit mobility. No effective treatment.

20. External resorption of the apical region of a maxillary lateral incisor

21. Internal Resorption Internal resorption occurs within the crown or root of a tooth. Involves the pulp chamber, pulp canals, and surrounding dentin It is believed to be precipitated by factors such as trauma, pulp capping, and pulp polyps. It appears as a round-to-ovoid radiolucency in the midcrown or midroot portion of the tooth. Endodontic therapy is recommended if perforation has not occurred. Generally asymptomatic. Treatment is variable. If the tooth is weakened by the resorptive process, extraction is recommended.

22. Internal resorption seen as a round radiolucency in the cervical region of a mandibular second premolar.

23. Internal resorption seen as a radiolucency in the root of a maxillary central incisor.

24. Pulpal Lesions Viewed on Dental Images Examination of the pulp chambers and canals is impossible without dental images. Dental images may detect conditions such as: Pulpal sclerosis Pulpal obliteration Pulp stones Many dental procedures require information about the size and location of the pulp cavity before treatment begins.

25. Pulpal Sclerosis Pulpal sclerosis is diffuse calcification of the pulp chamber and pulp canals of teeth. Results in a pulp cavity of reduced size It is associated with aging. It is of little clinical significance unless endodontic therapy is indicated. Conditions such as attrition, abrasion, caries, dental restorations, trauma, and abnormal mechanical forces may act as pulpal irritants and stimulate the production of secondary dentin that results in obliteration of the pulp cavity.

26. Thin atrophic pulp chambers in mandibular incisors

27. Pulpal Obliteration The calcification, or deposition of hard tissue, within the pulp cavity The production of secondary dentin may obliterate the pulp chamber. These teeth are nonvital and do not require treatment. May be caused by attrition, abrasion, caries, dental restorations, trauma, or abnormal mechanical forces. Tooth does not appear to have a pulp chamber or pulp canals.

28. Pulp canal obliteration in a maxillary central incisor

29. Pulp Stones Pulp stones are dystrophic calcifications found in the pulp chamber or pulp canals. They appear on dental images as round, ovoid, or cylindrical radiopacities. They may vary in shape, size, and number. They do not cause symptoms. They do not require treatment.

30. Cylindrical pulp stones in the mandibular canine and premolar.

31. An ovoid pulp stone in a maxillary lateral incisor

32. Periapical Lesions Viewed on Dental Images Periapical radiolucencies Periapical granuloma Periapical cyst Periapical abscess Periodontal abscess Periapical radiopacities Condensing osteitis Sclerotic bone Hypercementosis

33. Periapical Radiolucencies Periapical granulomas, cysts, and abscesses are commonly seen on dental images. These lesions cannot be diagnosed on their dental image appearance alone. Diagnosis is based on clinical features and dental image and microscopic appearance.

34. Infection of the pulp results in necrosis. A periapical granuloma, cyst, or abscess forms at the apex

35. Periapical Granuloma This is a localized mass of chronically inflamed granulation tissue at the apex of a nonvital tooth. It is the most common sequela of pulpitis. It may give rise to a cyst or to an abscess. Treatment is either endodontic therapy or removal of the tooth with curettage of the apical region. On dental images it appears as a widened periodontal ligament space at the root apex. This results from pulpal death or necrosis, or inflammation of the pulp. Typically asymptomatic but has history of prolonged sensitivity to heat or cold. The lamina dura is not visible between the root apex and the apical lesion

36. A widened periodontal ligament space at the apex of a maxillary lateral incisor

37. A periapical radiolucency associated with a mandibular premolar. (Note that the lamina dura is not visible.)

38. Periapical Cyst Periapical cyst is a lesion that develops over a long period. It results from cystic degeneration of the periapical granuloma. It is the most common of all tooth-related cysts. It is typically asymptomatic. Treatment is either endodontic therapy or extraction with curettage of the apical region. Also known as a radicular cyst. Results from pulpal death or necrosis. Comprise 50% to 70% of all cysts in the oral region. Appears as a round or ovoid radiolucency.

39. A well-defined round radiolucency seen at the apex of a mandibular central incisor

40. A large periapical radiolucent region appears on this panoramic image in the anterior mandible

41. Periapical Abscess This is a localized collection of pus around the apex of a nonvital tooth. Results from pulpal death. Acute Painful, nonvital; sensitive to pressure, percussion, and heat May not appear on dental images Chronic Usually asymptomatic; pus drains through bone or the periodontal ligament space Appears as a round or ovoid apical radiolucency

42. An increased widening of the periodontal ligament space seen in the periapical region of the mandibular first molar

43. Periapical radiolucencies associated with mandibular premolars

44. Periodontal Abscess Collection of pus that results from infection within the periodontal tissues (surrounding the tooth Acute destructive process Occurs as a complication of advanced periodontal disease Appears as a radiolucent area along the lateral aspect of the root Most common symptom is deep, throbbing pain Therapy includes drainage, subgingival scaling, and debridement of periodontal tissues What is the difference between a periapical abscess and a periodontal abscess?

45. A periodontal abscess is seen surrounding tooth #30.

46. Periapical Radiopacities The following are a few of the common periapical radiopacities that may be seen on dental images: These may be diagnosed based on their appearance, clinical information, and patient history Condensing osteitis Sclerotic bone Hypercementosis

47. Condensing Osteitis Condensing osteitis is a well-defined radiopacity. It is seen below the apex of a tooth with a history of long-standing pulpitis. It may vary in shape and size; does not appear to be attached to the tooth root. It is the most common periapical radiopacity observed in adults; most commonly in the mandibular third molar. Also known as chronic focal sclerosing osteomyelitis. The opacity represents a proliferation of periapical bone that is a result of a low-grade inflammation or mild irritation. No treatment is necessary.

48. A radiopacity seen along the roots of a mandibular first molar

49. Sclerotic Bone Sclerotic bone is a well-defined radiopacity seen below the apices of vital, noncarious teeth. It is of unknown cause. It is not attached to the tooth. It varies in size and shape. Margins may be smooth or irregular and diffuse. It is asymptomatic. Also known as osteosclerosis or idiopathic periapical osteosclerosis. Usually discovered on a routinely taken image.

50. A well-defined radiopacity below the apex of a mandibular premolar

51. Hypercementosis Hypercementosis is the excess deposition of cementum on root surfaces. May result from supereruption , inflammation, or trauma Most often affects the apical area, which appears enlarged and bulbous. Affected teeth are vital and do not require treatment. Root areas affected are separated from periapical bone by normal-appearing periodontal ligament space and lamina dura.

52. Hypercementosis of a maxillary premolar

53. Questions?