NDEE 2026 Exam 1
Questions and Correct
Answers with
Rationale
� Question 1
A 35-year-old patient presents with spontaneous gingival
bleeding, swollen interdental papillae, and heavy plaque
accumulation. Radiographs show no alveolar bone loss. What is
the most likely diagnosis?
A. Stage I Periodontitis
B. Plaque-induced Gingivitis
C. Necrotizing Periodontitis
D. Aggressive Periodontitis
� Correct Answer: B. Plaque-induced Gingivitis
,� Rationale:
Plaque-induced gingivitis is characterized by gingival
inflammation without loss of attachment or alveolar bone. It is
reversible with effective plaque removal and oral hygiene.
� Question 2
Which tooth usually has two roots and three canals?
A. Maxillary central incisor
B. Mandibular first molar
C. Maxillary first premolar
D. Mandibular canine
� Correct Answer: C. Maxillary first premolar
� Rationale:
The maxillary first premolar commonly has two roots (buccal
and palatal) and frequently contains three canals, although
anatomical variations are common.
� Question 3
Which cranial nerve provides motor innervation to the muscles
of mastication?
,A. Facial nerve (CN VII)
B. Trigeminal nerve – Mandibular division (CN V3)
C. Glossopharyngeal nerve (CN IX)
D. Hypoglossal nerve (CN XII)
� Correct Answer: B. Trigeminal nerve – Mandibular
division (CN V3)
� Rationale:
The mandibular division (V3) supplies the masseter, temporalis,
medial pterygoid, and lateral pterygoid muscles.
� Question 4
Which microorganism is most commonly associated with root
surface caries in older adults?
A. Lactobacillus species
B. Actinomyces species
C. Treponema denticola
D. Candida albicans
� Correct Answer: B. Actinomyces species
, � Rationale:
Actinomyces species are strongly associated with root caries,
particularly in older adults with gingival recession and exposed
root surfaces.
� Question 5
A patient taking bisphosphonates complains of exposed bone in
the mandible that has persisted for eight weeks after extraction.
What is the most likely diagnosis?
A. Dry socket
B. Medication-Related Osteonecrosis of the Jaw (MRONJ)
C. Osteomyelitis
D. Acute periodontal abscess
� Correct Answer: B. Medication-Related Osteonecrosis of
the Jaw (MRONJ)
� Rationale:
Persistent exposed bone in a patient receiving antiresorptive
medication is characteristic of MRONJ, particularly after
invasive dental treatment.
� Question 6
Questions and Correct
Answers with
Rationale
� Question 1
A 35-year-old patient presents with spontaneous gingival
bleeding, swollen interdental papillae, and heavy plaque
accumulation. Radiographs show no alveolar bone loss. What is
the most likely diagnosis?
A. Stage I Periodontitis
B. Plaque-induced Gingivitis
C. Necrotizing Periodontitis
D. Aggressive Periodontitis
� Correct Answer: B. Plaque-induced Gingivitis
,� Rationale:
Plaque-induced gingivitis is characterized by gingival
inflammation without loss of attachment or alveolar bone. It is
reversible with effective plaque removal and oral hygiene.
� Question 2
Which tooth usually has two roots and three canals?
A. Maxillary central incisor
B. Mandibular first molar
C. Maxillary first premolar
D. Mandibular canine
� Correct Answer: C. Maxillary first premolar
� Rationale:
The maxillary first premolar commonly has two roots (buccal
and palatal) and frequently contains three canals, although
anatomical variations are common.
� Question 3
Which cranial nerve provides motor innervation to the muscles
of mastication?
,A. Facial nerve (CN VII)
B. Trigeminal nerve – Mandibular division (CN V3)
C. Glossopharyngeal nerve (CN IX)
D. Hypoglossal nerve (CN XII)
� Correct Answer: B. Trigeminal nerve – Mandibular
division (CN V3)
� Rationale:
The mandibular division (V3) supplies the masseter, temporalis,
medial pterygoid, and lateral pterygoid muscles.
� Question 4
Which microorganism is most commonly associated with root
surface caries in older adults?
A. Lactobacillus species
B. Actinomyces species
C. Treponema denticola
D. Candida albicans
� Correct Answer: B. Actinomyces species
, � Rationale:
Actinomyces species are strongly associated with root caries,
particularly in older adults with gingival recession and exposed
root surfaces.
� Question 5
A patient taking bisphosphonates complains of exposed bone in
the mandible that has persisted for eight weeks after extraction.
What is the most likely diagnosis?
A. Dry socket
B. Medication-Related Osteonecrosis of the Jaw (MRONJ)
C. Osteomyelitis
D. Acute periodontal abscess
� Correct Answer: B. Medication-Related Osteonecrosis of
the Jaw (MRONJ)
� Rationale:
Persistent exposed bone in a patient receiving antiresorptive
medication is characteristic of MRONJ, particularly after
invasive dental treatment.
� Question 6
