1
NDEB Exam Practice Exam and Study Guide
with Complete Questions Actual Exam 2026/2027
– Complete Exam-Style Questions with Detailed
Rationales | Pass Guaranteed – A+ Graded
[SECTION 1: Oral Diagnosis & Treatment Planning — Questions 1-15]
Q1: A 45-year-old patient presents with a fractured maxillary central incisor with exposed dentin
but no pulpal exposure. The tooth is asymptomatic. What is the most appropriate initial
treatment?
A. Root canal therapy
B. Extraction and implant placement
C. Protective cavity preparation and composite restoration [CORRECT]
D. Full coverage porcelain crown
Correct Answer: C
Rationale: The clinical presentation describes a complicated crown fracture without pulp
exposure (Ellis Class II). The primary goal is to protect the pulp and restore the tooth structure. A
protective restoration (composite or glass ionomer) is indicated to cover the dentin and restore
aesthetics/function. Root canal is unnecessary as the pulp is vital; extraction and full crowns are
overtreatment for a fracture that can be restored conservatively.
Q2: During a new patient examination, you notice a white, corrugated plaque on the lateral
border of the tongue that cannot be wiped off. The patient reports no pain. What is the most
likely diagnosis?
A. Candidiasis
B. Hairy leukoplakia
C. Lichen planus [CORRECT]
D. Erythroplakia
,2
Correct Answer: C
Rationale: Lichen planus often presents as white, raised, lace-like (stratified) plaques on the
buccal mucosa or tongue, which are not removable by scraping. Candidiasis is typically creamy
and removable; hairy leukoplakia is associated with HIV and usually appears on the lateral
tongue but has a distinct "hairy" texture; erythroplakia is a red, velvety lesion with a much higher
malignant potential than white lesions.
Q3: When assessing the risk for caries, which factor is classified as a high-risk indicator
according to CAMBRA/Caries Management by Risk Assessment guidelines?
A. Recent intake of xylitol gum
B. Low saliva flow rate (xerostomia) [CORRECT]
C. Regular use of fluoride toothpaste
D. No visible cavitated lesions
Correct Answer: B
Rationale: Xerostomia (reduced salivary flow) is a major high-risk factor because saliva buffers
acid and provides minerals to the teeth. Xylitol use and fluoride toothpaste are protective factors
reducing risk. While cavitated lesions indicate disease, the risk factor that predisposes the patient
to new lesions is the lack of protective saliva.
Q4: A patient with a known allergy to Penicillin requires antibiotic prophylaxis for a dental
procedure. Which medication is the first-line choice according to AHA guidelines?
A. Amoxicillin 2g
B. Clindamycin 600 mg [CORRECT]
C. Azithromycin 500 mg
D. Cephalexin 2g
Correct Answer: B
Rationale: For patients allergic to penicillin, the standard regimen is Clindamycin 600 mg taken
orally 1 hour before the procedure. Amoxicillin is contraindicated due to allergy; Cephalosporins
,3
are avoided in patients with a history of anaphylaxis to penicillin due to cross-reactivity;
Azithromycin is a second-line option for those who cannot take Clindamycin.
Q5: In a treatment planning hierarchy, which condition must be addressed first?
A. Replacement of missing posterior teeth for function
B. Emergency management of acute odontogenic infection [CORRECT]
C. Esthetic bonding of anterior teeth
D. Recall and prophylaxis
Correct Answer: B
Rationale: Emergency conditions involving infection, pain, or hemorrhage take precedence over
all other phases of dental treatment due to immediate health risks. Once the emergency is
resolved, phase II (disease control/caries) and phase III (definitive restorative/rehabilitation) can
proceed.
Q6: A patient presents with severe pain on the lower right quadrant. Clinical exam shows a deep
carious lesion on tooth #30 (first molar) with a large restoration. Percussion is positive, and cold
testing elicits no response. What is the diagnosis?
A. Reversible pulpitis
B. Irreversible pulpitis with symptomatic apical periodontitis [CORRECT]
C. Normal pulp
D. Acute apical abscess
Correct Answer: B
Rationale: Positive percussion indicates inflammation extending into the periapical tissues
(periodontitis). Lack of response to cold suggests pulp necrosis or irreversible damage, while the
severe pain points to symptomatic apical periodontitis. An apical abscess would also present with
swelling/fever; reversible pulpitis would have lingering pain to cold but normal percussion.
, 4
Q7: Which radiographic view is best suited for detecting interproximal caries in the posterior
teeth?
A. Periapical radiograph
B. Panoramic radiograph
C. Bitewing radiograph [CORRECT]
D. Occlusal radiograph
Correct Answer: C
Rationale: Bitewing radiographs are the gold standard for detecting interproximal caries because
they provide high-resolution images of the crowns of both upper and lower teeth with open
contacts. Periapicals focus on the roots/apices, and panoramics have lower resolution making
early interproximal decay difficult to visualize.
Q8: A patient has a history of intravenous drug use and reports fatigue. Oral examination reveals
a petechial-like rash on the hard palate. What condition is most consistent with these findings?
A. Kaposi's sarcoma
B. HIV-associated thrombocytopenia
C. Infective endocarditis (embolic phenomenon) [CORRECT]
D. Syphilis
Correct Answer: C
Rationale: While the history suggests HIV risk, the palatal petechiae (often called "palatal
petechiae" or "hyperemic lesions") along with fever and fatigue are classic signs of bacteremia or
infective endocarditis (Janeway lesions can occur elsewhere, but petechiae on the palate are
highly suggestive). It represents an embolic event. Kaposi's sarcoma appears as a red/purple
lesion, not typically petechial.
Q9: When reviewing a medical history, you note the patient is taking Warfarin. What is the most
critical dental management consideration?
A. Avoid using local anesthetic with vasoconstrictors.
NDEB Exam Practice Exam and Study Guide
with Complete Questions Actual Exam 2026/2027
– Complete Exam-Style Questions with Detailed
Rationales | Pass Guaranteed – A+ Graded
[SECTION 1: Oral Diagnosis & Treatment Planning — Questions 1-15]
Q1: A 45-year-old patient presents with a fractured maxillary central incisor with exposed dentin
but no pulpal exposure. The tooth is asymptomatic. What is the most appropriate initial
treatment?
A. Root canal therapy
B. Extraction and implant placement
C. Protective cavity preparation and composite restoration [CORRECT]
D. Full coverage porcelain crown
Correct Answer: C
Rationale: The clinical presentation describes a complicated crown fracture without pulp
exposure (Ellis Class II). The primary goal is to protect the pulp and restore the tooth structure. A
protective restoration (composite or glass ionomer) is indicated to cover the dentin and restore
aesthetics/function. Root canal is unnecessary as the pulp is vital; extraction and full crowns are
overtreatment for a fracture that can be restored conservatively.
Q2: During a new patient examination, you notice a white, corrugated plaque on the lateral
border of the tongue that cannot be wiped off. The patient reports no pain. What is the most
likely diagnosis?
A. Candidiasis
B. Hairy leukoplakia
C. Lichen planus [CORRECT]
D. Erythroplakia
,2
Correct Answer: C
Rationale: Lichen planus often presents as white, raised, lace-like (stratified) plaques on the
buccal mucosa or tongue, which are not removable by scraping. Candidiasis is typically creamy
and removable; hairy leukoplakia is associated with HIV and usually appears on the lateral
tongue but has a distinct "hairy" texture; erythroplakia is a red, velvety lesion with a much higher
malignant potential than white lesions.
Q3: When assessing the risk for caries, which factor is classified as a high-risk indicator
according to CAMBRA/Caries Management by Risk Assessment guidelines?
A. Recent intake of xylitol gum
B. Low saliva flow rate (xerostomia) [CORRECT]
C. Regular use of fluoride toothpaste
D. No visible cavitated lesions
Correct Answer: B
Rationale: Xerostomia (reduced salivary flow) is a major high-risk factor because saliva buffers
acid and provides minerals to the teeth. Xylitol use and fluoride toothpaste are protective factors
reducing risk. While cavitated lesions indicate disease, the risk factor that predisposes the patient
to new lesions is the lack of protective saliva.
Q4: A patient with a known allergy to Penicillin requires antibiotic prophylaxis for a dental
procedure. Which medication is the first-line choice according to AHA guidelines?
A. Amoxicillin 2g
B. Clindamycin 600 mg [CORRECT]
C. Azithromycin 500 mg
D. Cephalexin 2g
Correct Answer: B
Rationale: For patients allergic to penicillin, the standard regimen is Clindamycin 600 mg taken
orally 1 hour before the procedure. Amoxicillin is contraindicated due to allergy; Cephalosporins
,3
are avoided in patients with a history of anaphylaxis to penicillin due to cross-reactivity;
Azithromycin is a second-line option for those who cannot take Clindamycin.
Q5: In a treatment planning hierarchy, which condition must be addressed first?
A. Replacement of missing posterior teeth for function
B. Emergency management of acute odontogenic infection [CORRECT]
C. Esthetic bonding of anterior teeth
D. Recall and prophylaxis
Correct Answer: B
Rationale: Emergency conditions involving infection, pain, or hemorrhage take precedence over
all other phases of dental treatment due to immediate health risks. Once the emergency is
resolved, phase II (disease control/caries) and phase III (definitive restorative/rehabilitation) can
proceed.
Q6: A patient presents with severe pain on the lower right quadrant. Clinical exam shows a deep
carious lesion on tooth #30 (first molar) with a large restoration. Percussion is positive, and cold
testing elicits no response. What is the diagnosis?
A. Reversible pulpitis
B. Irreversible pulpitis with symptomatic apical periodontitis [CORRECT]
C. Normal pulp
D. Acute apical abscess
Correct Answer: B
Rationale: Positive percussion indicates inflammation extending into the periapical tissues
(periodontitis). Lack of response to cold suggests pulp necrosis or irreversible damage, while the
severe pain points to symptomatic apical periodontitis. An apical abscess would also present with
swelling/fever; reversible pulpitis would have lingering pain to cold but normal percussion.
, 4
Q7: Which radiographic view is best suited for detecting interproximal caries in the posterior
teeth?
A. Periapical radiograph
B. Panoramic radiograph
C. Bitewing radiograph [CORRECT]
D. Occlusal radiograph
Correct Answer: C
Rationale: Bitewing radiographs are the gold standard for detecting interproximal caries because
they provide high-resolution images of the crowns of both upper and lower teeth with open
contacts. Periapicals focus on the roots/apices, and panoramics have lower resolution making
early interproximal decay difficult to visualize.
Q8: A patient has a history of intravenous drug use and reports fatigue. Oral examination reveals
a petechial-like rash on the hard palate. What condition is most consistent with these findings?
A. Kaposi's sarcoma
B. HIV-associated thrombocytopenia
C. Infective endocarditis (embolic phenomenon) [CORRECT]
D. Syphilis
Correct Answer: C
Rationale: While the history suggests HIV risk, the palatal petechiae (often called "palatal
petechiae" or "hyperemic lesions") along with fever and fatigue are classic signs of bacteremia or
infective endocarditis (Janeway lesions can occur elsewhere, but petechiae on the palate are
highly suggestive). It represents an embolic event. Kaposi's sarcoma appears as a red/purple
lesion, not typically petechial.
Q9: When reviewing a medical history, you note the patient is taking Warfarin. What is the most
critical dental management consideration?
A. Avoid using local anesthetic with vasoconstrictors.
