25 The Use of Radiographs in the Evaluation of Periodontal Diseases

Objectives Define the key words. List the uses of radiographs in the assessment of periodontal diseases. Differentiate between horizontal and vertical bone loss. Identify three local contributing factors for periodontal disease that radiographs can help locate.

Objectives Explain how imaging anatomical configurations aids in the prognosis of periodontally involved teeth. List the limitations of radiographs in the assessment of periodontal diseases. Recognize the role vertical and horizontal angulations play in imaging periodontal diseases.

Objectives Use the appropriate radiographic techniques to best detect and evaluate periodontal diseases. Describe the radiographic appearance of the normal periodontium. List four American Academy of Periodontology disease classification case types and describe their radiographic appearance.

Key Words Alveolar (crestal) bone Calculus Cementoenamel junction (CEJ) Furcation involvement Generalized bone loss Gingivitis Horizontal bone loss Interdental septa

Key Words Lamina dura Local contributing factor Localized bone loss Occlusal trauma Pathogens Periodontal diseases

Key Words Periodontal ligament space Periodontitis Periodontium Triangulation Vertical (angular) bone loss Vertical bitewing series

Introduction Dental radiographs play a key role in the diagnosis, prognosis, management, and evaluation of periodontal diseases. Properly exposed and meticulously processed radiographs are invaluable aids in the diagnosis of periodontal diseases.

Introduction To get the most diagnostic information from radiographs taken to image periodontal status, radiographers should have an extensive knowledge of the radiographic techniques that will produce quality images.

Radiographic Appearance of Periodontal Diseases Gingivitis Periodontitis

Radiographic Examination Uses Limitations

BOX 25-1 Periodontal Bone Changes Recorded by Radiographs

Figure 25-1 Drawing illustrating horizontal bone loss Figure 25-1 Drawing illustrating horizontal bone loss. (A) Normal (physiologic) level of bone (alveolar bone parallel to the cementoenamel junction) and (B) Bone level of patient with periodontal disease. Horizontal bone loss is the difference between (A) and (B) (shaded area).

Figure 25-2 Horizontal bone loss Figure 25-2 Horizontal bone loss. Arrows show bone level of patient with periodontal disease. Note that the level of bone loss is parallel to an imaginary line drawn between the cementoenamel junctions of the adjacent teeth.

Figure 25-3 Drawing illustrating vertical bone loss Figure 25-3 Drawing illustrating vertical bone loss. Vertical bone loss appears angular where the resorption is greater on the side of one tooth than on the side of the adjacent tooth.

Figure 25-4 Vertical bone loss Figure 25-4 Vertical bone loss. Arrows show bone level of patient with periodontal disease.

Figure 25-5 Comparison of horizontal and verical bone loss Figure 25-5 Comparison of horizontal and verical bone loss. Use the CEJ of adjacent teeth as a guideline. (1) Horizontal bone loss. (2) Vertical bone loss.

Figure 25-6 Furcation involvement Figure 25-6 Furcation involvement. Note the radiolucency in between the roots of these multirooted teeth.

Figure 25-7 Local contributing factors Figure 25-7 Local contributing factors. Calculus (arrow) and amalgam overhang (circled) are likely to collect bacterial pathogens that can contribute to the progression of periodontal diseases.

Figure 25-8 Calculus. (1) large deposits around the necks of the teeth Figure 25-8 Calculus. (1) large deposits around the necks of the teeth. (2) Height of alveolar bone remaining as a result of periodontal disease.

Figure 25-9 Triangulation Figure 25-9 Triangulation. Widening of the periodontal ligament space indicative of occlusal trauma.

Figure 25-10 Root length and root-to-crown ratio Figure 25-10 Root length and root-to-crown ratio. Although the bone loss observed on this radiograph is significant, the longer than normal, dilacerated root improves the prognosis for the canine.

Figure 25-11 Comparsion of bitewing and periapcial radiographs imaging the periodontium. (A) Vertical bitewing. (B) Horizontal bitewing. (C) Periapical.

Figure 25-12 Correct and incorrect vertical angulation Figure 25-12 Correct and incorrect vertical angulation. (A) Correct vertical angulation accurately records crestal bone indicating no bone loss between the mandibular first and second molars. (B) Incorrect vertical angulation produces a radiolucent, cupping-out appearance of the lamina dura falsely indicating bone loss between these same teeth. (Thomson, E. M., & Tolle, S. L. (1994). A practical guide for using radiographs in the assessment of periodontal diseases. Part 2: Interpretation and future advances. Journal of Practical Hygiene, 3(2), 12. Permission from Montage Media.)

Figure 25-13 Correct and incorrect vertical angulation Figure 25-13 Correct and incorrect vertical angulation. (A) Correct vertical angulation accurately records crestal bone indicating bone loss mesial and distal to the maxillary first molar,. (B) Incorrect vertical angulation produces a false appearance to the level of bone in these same areas. (Thomson, E. M., & Tolle, S. L. (1994). A practical guide for using radiographs in the assessment of periodontal diseases. Part 2: Interpretation and future advances. Journal of Practical Hygiene, 3(2), 12. Permission from Montage Media.)

Figure 25-14 Example of varying horizontal angulation Figure 25-14 Example of varying horizontal angulation. (A) Correct horizontal angulation, but image does not reveal the vertical (angular) defect on the mesial of the maxillary first molar. (B). Slightly varied horizontal angulation of the same region now reveals the vertical bony defect. (Thomson, E. M., & Tolle, S. L. (1994). A practical guide for using radiographs in the assessment of periodontal diseases. Part 2: Interpretation and future advances. Journal of Practical Hygiene, 3(2), 13. Permission from Montage Media.)

TABLE 25-1 American Academy of Periodontal Disease Classification

PROCEDURE 25-1 Radiographic interpretation for periodontal disease

Figure 25-15 Drawing illustrating Case Type I: Gingivitis Figure 25-15 Drawing illustrating Case Type I: Gingivitis. Alveolar crest located 1.5 to 2.0 mm apical to the cementoenamel junctions (CEJ) of the teeth.

Figure 25-16 Case Type I: Gingivitis-anterior region Figure 25-16 Case Type I: Gingivitis-anterior region. Note the normal pointed radiopaque appearance of the lamina dura and thin radiolucent line of the periodontal ligament space.

Figure 25-17 Case Type I: Gingivitis-posterior region Figure 25-17 Case Type I: Gingivitis-posterior region. Note the normal radiopaque flat appearance of the lamina dura and thin radiolucent line of the periodontal ligament space.

Figure 25-18 Drawing illustrating Case Type II: Slight Chronic Periodontitis.

Figure 25-19 Case Type II: Slight Chronic Periodontitisposterior region. Note the slight radiolucent cupping-out of the lamina dura, especially visible between the mandibular first and second molars. Radiopaque calculus is visible on the proximal surfaces of the teeth.

Figure 25-20 Case Type II: Slight Chronic Periodontitis-anterior region. Note the blunting of the lamina dura and slight radiolucent widening of the periodontal ligament space. Slightly radiopaque calculus is visible.

Figure 25-21 Case Type II: Slight Chronic Periodontitis-anterior region. Note the blunting of the lamina dura and slight radiolucent widening of the periodontal ligament space. Slightly radiopaque calculus is visible.

Figure 25-22 Case Type III: Moderate Chronic or Aggressive Periodontitis-anterior region. Note the 30–50 percent bone level resorption.

Figure 25-23 Case Type III: Moderate Chronic or Aggressive Periodontitis-posterior region. Note the 30–50 percent bone level resorption and radiolucency in the furca of the mandibular molars indicating furcation involvement.

Figure 25-24 Drawing illustrating Case Type IV: Advanced Chronic or Aggressive Periodontitis.

Figure 25-25 Case Type IV: Advanced Chronic or Aggressive Periodontitis-anterior region. Note the 50 percent or greater bone level resorption.

Figure 25-26 Case Type IV: Advanced Chronic or Aggressive Periodontitis-posterior region. Note the 50 percent or greater bone level resorption and obvious furcation involvement.

Review: Chapter Summary Periodontal diseases are diseases that affect both soft tissues (gingivitis) and bone around the teeth (periodontitis).

Review: Chapter Summary The uses of radiographs in the evaluation and treatment of periodontal diseases include imaging the supporting bone, locating local contributing factors, imaging anatomical configurations; evaluating prognosis and treatment intervention needs; and serving as a baseline for identifying and documenting the progression of the disease and the results of treatment.

Recall: Study Questions General Chapter Review

Reflect: Case Study Describe what radiographic changes in the periodontium you would expect to observe on a seven-image series of vertical bitewings on the following patients classified according to the American Academy of Periodontology Disease Classification:

Reflect: Case Study Case Type I: Gingivitis Case Type II: Slight Chronic Periodontitis Case Type III: Moderate Chronic or Aggressive Periodontitis Case Type IV: Advanced Chronic or Aggressive Periodontitis

Relate: Laboratory Application Proceed to Chapter 25, Laboratory Application, to complete this activity.