Oral Surgery · single question
A partially erupted mandibular third molar (wisdom tooth) is visible in a panoramic radiograph. What complication is most likely to occur in the future?
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Correct answer: A. Pericoronitis
A partially erupted mandibular third molar is covered by a flap of gingival tissue (operculum) that creates a space where bacteria can accumulate, leading to PERICORONITIS — infection of the tissue surrounding a partially erupted tooth. Pericoronitis is the most common complication of partially erupted wisdom teeth, occurring in ~25% of patients with impacted third molars. External resorption and primordial cysts are less common. Distal caries on #18 can occur but is less predictable than pericoronitis.
- A. CORRECT. PERICORONITIS is the most common complication of partially erupted mandibular third molars. The operculum (gingival flap) over the partially erupted tooth traps bacteria, causing acute or chronic infection of the surrounding tissue.
- B. INCORRECT. External root resorption of adjacent teeth can occur from pressure by impacted third molars but is not the most common complication.
- C. INCORRECT. A primordial cyst develops when the stellate reticulum of an unerupted tooth degenerates before enamel formation — this would mean the tooth never formed, not a complication of a partially erupted tooth.
- D. INCORRECT. While periodontal defects can develop distal to the second molar with an impacted third molar, pericoronitis is the more immediate and most common complication.
- E. INCORRECT. Caries on the distal surface of tooth #18 (adjacent second molar) can occur due to food trapping, but this is less predictable and common than pericoronitis.