Start practicing

Radiology · patient case with 3 questions

84-year-old with a heavily restored dentition

Patient: 84-year-old man, first visit in several years.

Chief complaint: Wants his mouth checked over.

History: Medically stable, independent, no bisphosphonates, no radiotherapy. Good manual dexterity.

Findings: Radiographs show amalgam restorations in nearly all posterior teeth. On one posterior molar roughly half the coronal tooth appears absent with a clean cavity outline. A premolar looks clinically like a retained root, but radiographically the root is intact, the canal is patent, and bone support is good. A third tooth has an established periapical infection.

Question 1

What most likely happened to the posterior molar?

  1. The restoration was lost
  2. Recurrent caries destroyed the entire crown
  3. Internal resorption hollowed out the crown
  4. The tooth is congenitally malformed
Show answer and explanation

Correct answer: A. The restoration was lost

  • A. CORRECT. A clean, sharply outlined cavity where an amalgam used to sit, with the surrounding tooth structure intact, is a LOST restoration. The preparation outline is still recognizable because it was cut, not dissolved.
  • B. Recurrent caries produces an ill-defined, irregular radiolucency undermining the remaining structure, not a clean preparation outline.
  • C. Internal resorption is a radiolucent expansion centred on the pulp space, continuous with the canal.
  • D. A congenital malformation would have been present lifelong, not a new change in a restored tooth.

Permanent page for this question

Question 2

The premolar looks like a root tip clinically but has an intact root, patent canal, and good bone support. What is the MOST appropriate treatment?

  1. Extraction and immediate implant placement
  2. Post and crown without root canal treatment
  3. Root canal treatment, core build-up, post, and crown
  4. Crown alone
Show answer and explanation

Correct answer: C. Root canal treatment, core build-up, post, and crown

  • A. Extracting a restorable tooth to place an implant is more invasive, more expensive, and discards healthy bone-supported root structure for no clinical gain.
  • B. A post cannot be placed in a vital or untreated canal. Endodontic treatment must come first.
  • C. CORRECT. Sound root structure with adequate bone support in a patient with good dexterity is worth saving. The sequence is endodontic treatment first, then a foundation restoration, then a post ONLY if insufficient coronal structure remains to retain the core, then a crown with an adequate ferrule.
  • D. A crown needs something to sit on. With most of the coronal tooth gone, there is no retention or ferrule without a core.

Permanent page for this question

Question 3

For the tooth with the periapical infection, all of the following argue against immediate implant placement EXCEPT:

  1. The patient's chronological age
  2. Inadequate bone volume or a damaged buccal plate
  3. Inability to achieve primary stability
  4. Active infection at the site
Show answer and explanation

Correct answer: A. The patient's chronological age

  • A. CORRECT — this is the exception. CHRONOLOGICAL AGE is not a contraindication in adults. What matters is SKELETAL MATURITY at the young end and systemic health, bone quality and healing capacity at the older end. A healthy 84-year-old is a better candidate than a growing 15-year-old.
  • B. Insufficient bone or a lost buccal plate prevents placing the fixture in the correct three-dimensional position.
  • C. Without primary stability the implant micromoves during healing and fibrous encapsulation follows instead of osseointegration.
  • D. Active periapical infection compromises healing and osseointegration and is a genuine reason to delay.

Permanent page for this question

Practice patient cases Radiology study notes