INBDE Oral Surgery Practice Exam 2026
| 100 Advanced Questions & Answers
with Detailed Rationales | Integrated
National Board Dental Examination
Prep & Study Guide
1.
A 24-year-old patient presents for removal of an impacted mandibular third
molar. Panoramic imaging shows the roots closely superimposed over the inferior
alveolar canal, with darkening of the roots and interruption of the canal’s cortical
border. Which additional imaging modality is most useful for determining the
three-dimensional relationship between the tooth roots and mandibular canal?
A. Bitewing radiograph
B. Occlusal radiograph
C. Periapical radiograph only
D. Cone-beam computed tomography
E. Lateral cephalometric radiograph
Answer: D. Cone-beam computed tomography
,Rationale: CBCT provides three-dimensional visualization of the spatial
relationship between the mandibular third molar roots and the inferior alveolar
canal. It is particularly useful when panoramic findings suggest a high risk of
inferior alveolar nerve injury.
2.
A patient develops persistent anesthesia of the lower lip and chin immediately
after mandibular third-molar surgery. Which nerve was most likely injured?
A. Lingual nerve
B. Mental nerve
C. Inferior alveolar nerve
D. Long buccal nerve
E. Mylohyoid nerve
Answer: C. Inferior alveolar nerve
Rationale: The inferior alveolar nerve supplies sensation to the mandibular teeth
and, through the mental nerve, the lower lip and chin. Persistent postoperative
paresthesia in this distribution suggests inferior alveolar nerve injury.
3.
During extraction of a mandibular third molar, the lingual nerve is accidentally
traumatized. Which sensory deficit is most likely?
A. Loss of sensation of the lower lip
B. Loss of sensation of the anterior two-thirds of the tongue
C. Loss of sensation of the posterior one-third of the tongue
D. Loss of sensation of the mandibular teeth
E. Loss of sensation of the chin
Answer: B. Loss of sensation of the anterior two-thirds of the tongue
,Rationale: The lingual nerve provides general somatic sensation to the anterior
two-thirds of the tongue, floor of mouth, and lingual gingiva. Taste fibers from
the chorda tympani travel with it as well.
4.
A 35-year-old patient requires surgical removal of a deeply impacted mandibular
third molar. Which factor most strongly increases the risk of postoperative
mandibular fracture?
A. Patient age of 20 years
B. Mesioangular impaction
C. Extensive removal of mandibular bone
D. Use of a surgical handpiece
E. Administration of local anesthesia
Answer: C. Extensive removal of mandibular bone
Rationale: Removal of substantial mandibular bone, particularly in older
patients or deeply impacted molars, can significantly weaken the mandible and
increase the risk of postoperative fracture.
5.
A patient presents 4 days after mandibular third-molar extraction with severe
throbbing pain and foul odor. Examination reveals an empty extraction socket
with exposed bone but no significant swelling or purulence. What is the most
likely diagnosis?
A. Acute osteomyelitis
B. Periapical abscess
C. Alveolar osteitis
D. Cellulitis
E. Osteosarcoma
, Answer: C. Alveolar osteitis
Rationale: Alveolar osteitis, or dry socket, typically develops several days after
extraction and causes severe pain associated with loss or breakdown of the
blood clot and exposed socket bone.
6.
Which intervention is most appropriate for managing a typical dry socket?
A. Immediate surgical curettage of the socket
B. Systemic antibiotics for every patient
C. Irrigation followed by placement of a medicated dressing
D. Immediate extraction of adjacent teeth
E. Primary closure of the socket
Answer: C. Irrigation followed by placement of a medicated dressing
Rationale: Treatment is primarily symptomatic. Gentle irrigation removes
debris, while an appropriate medicated dressing can provide analgesia. Routine
systemic antibiotics are not indicated unless there is evidence of spreading
infection or systemic involvement.
7.
A patient taking warfarin requires extraction of a non-restorable tooth. What is
the most appropriate initial laboratory assessment?
A. Bleeding time
B. Platelet count only
C. INR
D. Activated partial thromboplastin time
E. Serum fibrinogen only
| 100 Advanced Questions & Answers
with Detailed Rationales | Integrated
National Board Dental Examination
Prep & Study Guide
1.
A 24-year-old patient presents for removal of an impacted mandibular third
molar. Panoramic imaging shows the roots closely superimposed over the inferior
alveolar canal, with darkening of the roots and interruption of the canal’s cortical
border. Which additional imaging modality is most useful for determining the
three-dimensional relationship between the tooth roots and mandibular canal?
A. Bitewing radiograph
B. Occlusal radiograph
C. Periapical radiograph only
D. Cone-beam computed tomography
E. Lateral cephalometric radiograph
Answer: D. Cone-beam computed tomography
,Rationale: CBCT provides three-dimensional visualization of the spatial
relationship between the mandibular third molar roots and the inferior alveolar
canal. It is particularly useful when panoramic findings suggest a high risk of
inferior alveolar nerve injury.
2.
A patient develops persistent anesthesia of the lower lip and chin immediately
after mandibular third-molar surgery. Which nerve was most likely injured?
A. Lingual nerve
B. Mental nerve
C. Inferior alveolar nerve
D. Long buccal nerve
E. Mylohyoid nerve
Answer: C. Inferior alveolar nerve
Rationale: The inferior alveolar nerve supplies sensation to the mandibular teeth
and, through the mental nerve, the lower lip and chin. Persistent postoperative
paresthesia in this distribution suggests inferior alveolar nerve injury.
3.
During extraction of a mandibular third molar, the lingual nerve is accidentally
traumatized. Which sensory deficit is most likely?
A. Loss of sensation of the lower lip
B. Loss of sensation of the anterior two-thirds of the tongue
C. Loss of sensation of the posterior one-third of the tongue
D. Loss of sensation of the mandibular teeth
E. Loss of sensation of the chin
Answer: B. Loss of sensation of the anterior two-thirds of the tongue
,Rationale: The lingual nerve provides general somatic sensation to the anterior
two-thirds of the tongue, floor of mouth, and lingual gingiva. Taste fibers from
the chorda tympani travel with it as well.
4.
A 35-year-old patient requires surgical removal of a deeply impacted mandibular
third molar. Which factor most strongly increases the risk of postoperative
mandibular fracture?
A. Patient age of 20 years
B. Mesioangular impaction
C. Extensive removal of mandibular bone
D. Use of a surgical handpiece
E. Administration of local anesthesia
Answer: C. Extensive removal of mandibular bone
Rationale: Removal of substantial mandibular bone, particularly in older
patients or deeply impacted molars, can significantly weaken the mandible and
increase the risk of postoperative fracture.
5.
A patient presents 4 days after mandibular third-molar extraction with severe
throbbing pain and foul odor. Examination reveals an empty extraction socket
with exposed bone but no significant swelling or purulence. What is the most
likely diagnosis?
A. Acute osteomyelitis
B. Periapical abscess
C. Alveolar osteitis
D. Cellulitis
E. Osteosarcoma
, Answer: C. Alveolar osteitis
Rationale: Alveolar osteitis, or dry socket, typically develops several days after
extraction and causes severe pain associated with loss or breakdown of the
blood clot and exposed socket bone.
6.
Which intervention is most appropriate for managing a typical dry socket?
A. Immediate surgical curettage of the socket
B. Systemic antibiotics for every patient
C. Irrigation followed by placement of a medicated dressing
D. Immediate extraction of adjacent teeth
E. Primary closure of the socket
Answer: C. Irrigation followed by placement of a medicated dressing
Rationale: Treatment is primarily symptomatic. Gentle irrigation removes
debris, while an appropriate medicated dressing can provide analgesia. Routine
systemic antibiotics are not indicated unless there is evidence of spreading
infection or systemic involvement.
7.
A patient taking warfarin requires extraction of a non-restorable tooth. What is
the most appropriate initial laboratory assessment?
A. Bleeding time
B. Platelet count only
C. INR
D. Activated partial thromboplastin time
E. Serum fibrinogen only
