A panoramic radiograph shows a partially impacted third molar pressing against the root of the second molar. What complication could occur in the future?

Correct answer: C. Periodontal defect only

• A. Incorrect. Periodontal defects can occur but the primary radiographic concern when an impacted tooth presses against an adjacent root is resorption.
• B. Incorrect. Caries on distal #18 requires established contact and food trapping, not the primary radiographic prediction.
• C. Correct. An impacted third molar pressing against the root of the second molar causes external (pressure) root resorption of the adjacent tooth — the classic future complication.
• D. Incorrect. Pericoronitis is a current complication of partial eruption, not a future radiographic prediction.

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