NDEB - National Dental Examining Board Periodontal Disease and Management Questions and Answers — Questions and Answers
Question 1: A 45-year-old male patient presents with generalized probing depths of 5-6 mm, radiographic evidence of bone loss extending to the middle third of the root on several teeth, and Class II furcation involvement on tooth #30. According to the 2017 AAP/EFP classification, what is the most appropriate Stage for this patient's periodontitis?
- Stage I
- Stage II
- Stage III (Correct answer)
- Stage IV
Correct answer: Stage III
The patient is classified as Stage III periodontitis. This stage is defined by severe periodontitis with the potential for additional tooth loss. Key indicators for Stage III include probing depths of ≥6 mm, radiographic bone loss extending to the mid-third of the root or beyond, and/or Class II or III furcation involvement. The presence of Class II furcation involvement and bone loss to the middle third of the root automatically places the patient in at least Stage III, regardless of clinical attachment loss.
Question 2: Which of the following is the primary goal of non-surgical periodontal therapy, such as scaling and root planing?
- To regenerate lost alveolar bone.
- To eliminate the need for future periodontal maintenance.
- To create a new connective tissue attachment to the root surface.
- To remove biofilm and calculus to create a biologically acceptable root surface. (Correct answer)
Correct answer: To remove biofilm and calculus to create a biologically acceptable root surface.
The primary objective of non-surgical periodontal therapy is to eliminate the etiologic factors of periodontal disease, which are bacterial plaque biofilm and calculus. By thoroughly debriding the root surfaces, a biologically acceptable environment is created, which promotes healing of the periodontal tissues, reduction in inflammation, and a decrease in probing depths. Regeneration of bone and new attachment are goals of surgical regenerative procedures, not initial non-surgical therapy.
Question 3: A patient diagnosed with Stage II, Grade B periodontitis is a smoker (15 cigarettes/day) and has poorly controlled Type 2 diabetes (HbA1c of 8.5%). According to the 2017 classification, how would these risk factors influence the patient's Grade?
- The Grade would remain B as staging is the primary determinant.
- The Grade would be shifted to A (slow progression).
- The Grade would be shifted to C (rapid progression). (Correct answer)
- The Grade is independent of smoking and diabetic status.
Correct answer: The Grade would be shifted to C (rapid progression).
The grading system in the 2017 classification is designed to estimate the future risk of periodontitis progression. Grade B is the default moderate progression rate. However, specific risk factors can modify this grade. Smoking ≥10 cigarettes per day or having an HbA1c ≥7.0% are both indicators that shift the grade to C, signifying a high likelihood of rapid progression. Therefore, this patient's grade should be modified from B to C.
Question 4: Host modulation therapy (HMT) in periodontics, such as the use of sub-antimicrobial dose doxycycline (SDD), primarily aims to:
- Directly kill periodontal pathogens in the pocket.
- Inhibit the activity of matrix metalloproteinases (MMPs). (Correct answer)
- Stimulate the production of new alveolar bone.
- Increase the patient's immune response to plaque biofilm.
Correct answer: Inhibit the activity of matrix metalloproteinases (MMPs).
Host modulation therapy targets the host's destructive inflammatory response rather than the bacteria themselves. Sub-antimicrobial dose doxycycline (20mg twice daily) works primarily by inhibiting the activity of matrix metalloproteinases (MMPs), which are enzymes responsible for the breakdown of collagen and other connective tissues in the periodontium. It does not have a direct antibacterial effect at this low dose.
Question 5: Following successful non-surgical periodontal therapy, a patient is placed on a periodontal maintenance schedule. What is the most critical component of this long-term phase of treatment?
- Annual full-mouth radiographs.
- Application of topical fluoride at every visit.
- Regular removal of supragingival plaque only.
- Ongoing professional debridement and monitoring of periodontal status. (Correct answer)
Correct answer: Ongoing professional debridement and monitoring of periodontal status.
Periodontal maintenance is crucial for preventing the recurrence and progression of periodontitis. The most critical component is the regular, ongoing monitoring of clinical parameters (probing depths, bleeding on probing, attachment levels) and professional debridement of both supra- and subgingival plaque and calculus to prevent the re-establishment of a pathogenic biofilm. This phase is key to long-term stability.
Question 6: Under the 2017 World Workshop classification, the diagnostic categories of "chronic periodontitis" and "aggressive periodontitis" from the 1999 system were eliminated. What was the primary reason for this change?
- These conditions were found to be caused by completely different bacteria.
- Aggressive periodontitis was deemed too rare to be a separate category.
- There was insufficient evidence of distinct pathophysiological differences between the two forms. (Correct answer)
- Patients with aggressive periodontitis did not respond to conventional therapy.
Correct answer: There was insufficient evidence of distinct pathophysiological differences between the two forms.
The 2017 classification consolidated "chronic" and "aggressive" periodontitis into a single category of "periodontitis," which is then characterized by a staging and grading system. The primary rationale was the lack of strong scientific evidence to support them as two distinct diseases with different underlying biological mechanisms or pathophysiology. The new system focuses on a multi-dimensional view of the disease based on severity, complexity, and rate of progression for each individual patient.
NDEB - National Dental Examining Board Periodontal Disease and Management Questions and Answers
A 45-year-old male patient presents with generalized probing depths of 5-6 mm, radiographic evidence of bone loss extending to the middle third of the root on several teeth, and Class II furcation involvement on tooth #30.
According to the 2017 AAP/EFP classification, what is the most appropriate Stage for this patient's periodontitis?