An old root filling and a sharp cusp

Correct answer: A. Non-surgical retreatment — remove the silver points and obturate with gutta-percha

• A. CORRECT. The governing rule is that ORTHOGRADE (non-surgical) retreatment precedes any surgical approach whenever the canal can be renegotiated. Silver points seal poorly for a structural reason — they are round and canals are not, so the seal depends on a cement that washes out over time — and they CORRODE in the presence of tissue fluid, releasing cytotoxic silver corrosion products. The periapical lesion here reflects persistent intracanal infection, and that infection can only be eliminated from inside the canal. Remove the points, clean and shape thoroughly, disinfect, obturate with gutta-percha and sealer, and re-establish a proper coronal seal.
• B. Apicoectomy is reserved for cases where orthograde retreatment has FAILED or is genuinely impossible — a non-negotiable canal, a separated instrument that cannot be bypassed, an obstructive post that cannot be safely removed, or a lesion persisting after adequate retreatment. Raising a flap while leaving infected canal contents in place treats the symptom and leaves the cause. The recall makes exactly this point: retreat with gutta-percha first, and only then consider apicectomy.
• C. A symptomatic tooth with a sinus tract and an expanding periapical lesion requires treatment, not observation.
• D. The tooth is restorable and has not yet had appropriate treatment. Extraction is premature and replaces a treatable tooth with a more expensive problem.

Note: Technique: expose the coronal end of the point and grasp it with Steiglitz forceps or engage it with an ultrasonic tip; a Masserann kit or a Cancellier extractor is used when the point is fully embedded. Handle carefully — corroded silver points are brittle and fracture readily. Both gutta-percha and silver points can achieve high clinical success, so the presence of silver points ALONE, in an asymptomatic tooth with no periapical lesion and a sound coronal seal, is not by itself an indication to retreat.

Correct answer: B. Mandibular lateral incisor

• A. The maxillary canine has an OVAL access, its long axis labiopalatal, cut through the lingual surface. It has a single root with a single canal and the largest pulp chamber of the anterior teeth.
• B. CORRECT as the exception. The MANDIBULAR LATERAL INCISOR is the outlier in this group. Its crown is far narrower mesiodistally, the access is cut through the LINGUAL surface into a chamber that is ribbon-shaped buccolingually, and the outline must be extended incisally and lingually because a SECOND, LINGUAL CANAL is present in a substantial minority of mandibular incisors — commonly quoted around 40%. That second canal is missed precisely when a small conservative oval access is left as cut. Grouping it with the maxillary canine and the two maxillary premolars, which share a broad, straightforward buccopalatal oval, is what the question is testing.
• C. The maxillary second premolar has the same OVOID, buccopalatally oriented occlusal access. Usually a single root, with one or two canals.
• D. The maxillary first premolar has an OVOID access with its long axis buccopalatal, cut through the occlusal surface. Two canals in the great majority of cases, and two separate roots in roughly 60–70%.

Note: The outline shapes worth committing to memory. MAXILLARY: central triangular, lateral roughly ovoid, canine oval, both premolars ovoid, first and second molars triangular (rhomboidal for the first when MB2 is included). MANDIBULAR: incisors ovoid or elliptical, canine oval, both premolars ovoid, first molar rectangular or trapezoidal, second molar triangular. Whatever the shape, the principles do not change: straight-line access to the orifices, complete removal of the chamber ROOF, and preservation of the pulpal FLOOR with its developmental grooves.

Correct answer: A. Smooth or restore the sharp cusp and review in 10 to 14 days

• A. CORRECT. This is a traumatic ulcer with an obvious mechanical cause lying immediately against it. The governing rule in oral medicine is REMOVE THE CAUSE FIRST, THEN REVIEW. Smooth the sharp cusp by selective grinding, or restore the tooth, and re-examine at 10 to 14 days. A genuinely traumatic ulcer heals within that window once the irritant is gone.
• B. Excisional biopsy of an undiagnosed ulcer with a rolled margin is the worse of the two biopsy errors — if the lesion is malignant, excising it compromises staging and definitive surgical management.
• C. Biopsy is not the first step when a plausible and removable cause is present — but it becomes MANDATORY if the ulcer has not healed at the review appointment. A non-healing ulcer on the LATERAL BORDER OF THE TONGUE in an adult is squamous cell carcinoma until proven otherwise, and that site is the commonest intra-oral location for it. The rolled margin described here makes the review non-negotiable.
• D. A topical steroid applied without a diagnosis suppresses the inflammation, may mask progression, and delays the diagnosis of a potentially curable cancer.

Note: ⚠️ The recall recorded the two candidate answers as ‘take biopsy’ and ‘restore the cusp’, and settled on no biopsy. That is right AS THE FIRST STEP — but the answer is only safe if the review appointment is booked and kept. Removing the cause without arranging follow-up is the version of this that misses a carcinoma.