NBDE Diagnosis and Treatment Planning 5 — Questions and Answers
Question 1: A 50-year-old patient presents with a chief complaint of sensitivity to cold that lingers for 30 seconds on tooth #19. The tooth is otherwise asymptomatic, and periapical radiographs are normal. What is the most likely pulpal diagnosis?
- Normal pulp
- Reversible pulpitis
- Symptomatic irreversible pulpitis (Correct answer)
- Pulp necrosis
Correct answer: Symptomatic irreversible pulpitis
Lingering cold sensitivity (pain persisting after stimulus removal) indicates symptomatic irreversible pulpitis, indicating the pulp cannot heal and endodontic therapy is needed.
Question 2: A radiograph shows a diffuse, poorly defined radiopacity replacing the normal trabecular pattern of the posterior mandible in an elderly patient. The area is asymptomatic. What is the most likely diagnosis?
- Florid cemento-osseous dysplasia (Correct answer)
- Osteosarcoma
- Paget's disease of bone
- Chronic diffuse sclerosing osteomyelitis
Correct answer: Florid cemento-osseous dysplasia
Florid cemento-osseous dysplasia presents as diffuse, bilateral, asymptomatic sclerotic masses replacing trabecular bone, most commonly in middle-aged Black women.
Question 3: A patient scheduled for a complicated extraction has a blood pressure reading of 185/110 mmHg at the start of the appointment. What is the most appropriate management?
- Proceed with treatment using a vasoconstrictor-free local anesthetic
- Administer nitrous oxide sedation to reduce anxiety and proceed
- Defer treatment, refer to physician, and reschedule after blood pressure is controlled (Correct answer)
- Proceed with treatment but limit epinephrine to 1 carpule
Correct answer: Defer treatment, refer to physician, and reschedule after blood pressure is controlled
A blood pressure of ≥180/110 mmHg (Stage 3 hypertension) contraindicates elective dental surgery; the patient must be referred for medical management before rescheduling.
Question 4: Which finding on a clinical examination is most diagnostic of a vertical root fracture in a posterior tooth?
- Probing depth >6 mm on a single isolated narrow pocket (Correct answer)
- Positive cold sensitivity test
- Furcation involvement with no evidence of plaque-induced disease
- Periapical radiolucency with well-defined borders
Correct answer: Probing depth >6 mm on a single isolated narrow pocket
An isolated narrow, deep periodontal defect (sinus tract or narrow probing defect along the root surface) is pathognomonic of a vertical root fracture.
Question 5: A 25-year-old patient presents requesting whitening but has tetracycline staining that is moderate-to-severe (banding visible). What is the most realistic treatment planning discussion with the patient?
- In-office bleaching will fully resolve the staining in one session
- At-home bleaching alone will achieve complete resolution within 2 weeks
- Bleaching has limited effect; porcelain veneers or crowns may be needed for adequate results (Correct answer)
- No treatment can improve tetracycline staining — extraction and implants are indicated
Correct answer: Bleaching has limited effect; porcelain veneers or crowns may be needed for adequate results
Moderate-to-severe tetracycline staining responds poorly to bleaching alone, and porcelain veneers or full-coverage crowns are often required to achieve an acceptable esthetic outcome.
Question 6: A patient requires a fixed partial denture (FPD) replacing the mandibular first molar. The second premolar and second molar are the proposed abutments. What Ante's law consideration is critical to treatment planning?
- The pontic must be the same width as the missing tooth
- The combined root surface area of the abutments must be equal to or greater than that of the teeth being replaced (Correct answer)
- A minimum of three abutment teeth is required for any FPD
- The occlusal table of the pontic must be reduced by 50%
Correct answer: The combined root surface area of the abutments must be equal to or greater than that of the teeth being replaced
Ante's law states that the combined periodontal ligament area of the abutment teeth should be at least equal to that of the teeth being replaced to ensure adequate support.
Question 7: A 40-year-old patient is diagnosed with Stage II, Grade C periodontitis. What Grade C modifier best explains this classification if the patient is a non-smoker with good plaque control?
- Rapid bone loss relative to biofilm deposits (Correct answer)
- Smoking more than 10 cigarettes per day
- HbA1c ≥ 7% indicating uncontrolled diabetes
- Radiographic bone loss > 2 mm in 5 years
Correct answer: Rapid bone loss relative to biofilm deposits
Grade C periodontitis is identified when the rate of destruction is disproportionately severe relative to the level of plaque/biofilm, suggesting a highly susceptible host response.
NBDE Diagnosis and Treatment Planning 5
A 50-year-old patient presents with a chief complaint of sensitivity to cold that lingers for 30 seconds on tooth #19.
The tooth is otherwise asymptomatic, and periapical radiographs are normal.
What is the most likely pulpal diagnosis?