ABOMS Oral & Maxillofacial Surgery Exam Questions 2026–2027 | Correct Answers & Detailed Rationales | OMS Board Certification PDF

ABOMS Oral & Maxillofacial Surgery
Exam Questions 2026–2027 | Correct
Answers & Detailed Rationales | OMS
Board Certification PDF
ABOMS ORAL & MAXILLOFACIAL SURGERY EXAM QUESTIONS 2026–2027

Correct Answers & Detailed Rationales | OMS Board Certification



DOCUMENT OVERVIEW

• This comprehensive study material contains board-level multiple-choice questions
designed to reinforce critical knowledge and clinical decision-making skills across all
major domains of oral and maxillofacial surgery.

• Use this resource to identify knowledge gaps, practice time-management
strategies, and build confidence in clinical reasoning by studying the detailed
rationales for each correct answer.




QUESTION 1

A patient with a history of severe alveolar bone loss presents with mobile
teeth and bleeding gums. Which of the following is the primary etiology of
this clinical presentation?

A) Isolated plaque accumulation

B) Nutritional deficiency alone

C) Chronic periodontitis with loss of periodontal support

D) Traumatic occlusion without periodontal disease

E) Hereditary gingival fibromatosis

CORRECT ANSWER: C) Chronic periodontitis with loss of periodontal support

,RATIONALE: Chronic periodontitis is characterized by progressive destruction of
the periodontal ligament, cementum, and alveolar bone, leading to tooth mobility
and bleeding. While plaque is the causative agent, the clinical picture of severe
bone loss with mobility indicates established periodontitis rather than simple
gingivitis. Nutritional deficiency alone would not cause this pattern of destruction.
Traumatic occlusion alone does not destroy bone, and hereditary gingival
fibromatosis presents with gingival enlargement, not bone loss.



QUESTION 2

During extraction of a maxillary molar, you notice the tuberosity is being
elevated excessively. What anatomical structure lies posterior to the
maxillary tuberosity that must be protected?

A) Greater palatine artery and nerve

B) Pterygomandibular raphe

C) Pterygoid plexus of veins

D) Lingual artery

E) Glossopharyngeal nerve

CORRECT ANSWER: C) Pterygoid plexus of veins

RATIONALE: The pterygoid plexus of veins lies in the pterygomandibular space,
directly posterior to the maxillary tuberosity. Excessive elevation during maxillary
molar extraction can damage these veins, leading to hemorrhage into the
pterygomandibular space and potential airway compromise. The greater palatine
artery runs in the hard palate (anteriorly), the pterygomandibular raphe is a fascial
structure between masseter and superior constrictor, the lingual artery is intraoral
anteriorly, and the glossopharyngeal nerve is a cranial nerve not at risk in this
procedure.



QUESTION 3

,A 35-year-old female presents with a painless, slowly enlarging swelling of the
hard palate. Radiographs reveal a well-defined radiolucency crossing the
midline. Which diagnosis is most likely?

A) Nasopalatine duct cyst

B) Incisive papilla cyst

C) Median palatal cyst

D) Globulomaxillary cyst

E) Odontogenic keratocyst

CORRECT ANSWER: A) Nasopalatine duct cyst

RATIONALE: Nasopalatine duct cysts are the most common non-odontogenic cysts
of the maxilla, arising from remnants of the nasopalatine duct. They present as
painless, slowly enlarging swellings in the midline anterior hard palate and appear
as well-defined radiolucencies that cross the midline on radiographs. These cysts
are often asymptomatic and discovered incidentally. While incisive papilla cyst is
another name for this same lesion, nasopalatine duct cyst is the more accurate
terminology. Median palatal cysts and globulomaxillary cysts are rare, and
odontogenic keratocysts present differently with more aggressive features.



QUESTION 4

What is the blood supply to the inferior alveolar nerve?

A) Inferior alveolar artery only

B) Branches from the external carotid artery exclusively

C) Nutrient vessels running with the nerve (vasa nervorum)

D) Collateral circulation from mental and incisive arteries only

E) Direct anastomosis with the lingual artery

CORRECT ANSWER: C) Nutrient vessels running with the nerve (vasa
nervorum)

, RATIONALE: The inferior alveolar nerve receives its vascular supply through vasa
nervorum—nutrient vessels that run longitudinally along the nerve trunk. These
vessels arise from branches of the inferior alveolar artery and maintain nerve
viability. This intrinsic vascular supply is critical to understand during surgical
procedures. The inferior alveolar artery itself is the source, but it provides supply
indirectly through these nutrient vessels. Understanding vasa nervorum is essential
for preventing iatrogenic nerve damage, as rough handling or prolonged retraction
can compromise this delicate blood supply.



QUESTION 5

A patient undergoing orthognathic surgery is at risk for relapse. Which of the
following factors most significantly increases relapse potential?

A) Surgical technique alone

B) Inadequate correction of the underlying skeletal discrepancy

C) Post-operative function and adaptive remodeling of soft tissues

D) Excessive orthodontic movement pre-operatively

E) Use of rigid fixation

CORRECT ANSWER: C) Post-operative function and adaptive remodeling of soft
tissues

RATIONALE: Post-operative relapse in orthognathic surgery is primarily driven by
the adaptive remodeling of neuromuscular and soft tissue structures. The soft
tissues (muscles, fascia, skin) retain their original programmed length and tension
and attempt to restore the face to its pre-operative position. This is the most
significant biological factor in relapse. While surgical technique and rigid fixation
are important for initial stability, and inadequate correction contributes to relapse,
the neuromuscular adaptation and soft tissue remodeling is the dominant
mechanism. Pre-operative orthodontic movement actually helps reduce relapse by
preparing the dentition.