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Cases › Management · M6

Opening the access on an upper molar

Practice cases written from published sources. Not an exam or admissions result; your program and examiners decide.

PATIENT

A 34-year-old has a lingering ache after cold on the upper left first molar and the tooth is tender to biting. The radiograph shows a deep filling close to the pulp, and root canal treatment is planned.

FINDINGS
  • Tooth #14, the maxillary left first molar
  • Lingering pain after cold, tender to tapping
  • A deep filling close to the pulp on the radiograph
  • Plan: open an access into the pulp chamber and find the three canals
Question 1 of 2 · Management
You mark the access outline on #14. How far must its mesial extent sit from the mesial marginal ridge?

Right answer: At least 2.0 mm

The mesial extent of the access preparation is ≥ 2.0 mm from the mesial marginal ridge.

Source: Posterior endodontic procedure criteria sheet, 2026–27 season, p. 1 (critical errors, access placement, size, depth and roof removal, internal form, adjacent tooth, surrounding tissue)

Question 2 of 2 · Patient assessment
The finished outline is over the chamber but measures under 2.5 mm at its widest bucco-lingually. How do you read it?

Right answer: Too small

The access size is too small: <2.5 mm at its widest mesio-distally and/or < 2.5 mm at its widest bucco-lingually.

Source: Posterior endodontic procedure criteria sheet, 2026–27 season, p. 1 (critical errors, access placement, size, depth and roof removal, internal form, adjacent tooth, surrounding tissue)

That is the case. Each answer quoted the published source above.

Open M6 step 1 Next case
Cases › Management · M6
Opening the access on an upper molar

Practice cases written from published sources. Not an exam or admissions result; your program and examiners decide.

PATIENT

A 34-year-old has a lingering ache after cold on the upper left first molar and the tooth is tender to biting. The radiograph shows a deep filling close to the pulp, and root canal treatment is planned.

FINDINGS
  • Tooth #14, the maxillary left first molar
  • Lingering pain after cold, tender to tapping
  • A deep filling close to the pulp on the radiograph
  • Plan: open an access into the pulp chamber and find the three canals
Mark the access outline in the mesial pit and central fossa, M6 step 1M6 step 1: Mark the access outline in the mesial pit and central fossa. Open this step in the lesson.
Question 1 of 2 · Management
You mark the access outline on #14. How far must its mesial extent sit from the mesial marginal ridge?

Right answer: At least 2.0 mm

The mesial extent of the access preparation is ≥ 2.0 mm from the mesial marginal ridge.

Source: Posterior endodontic procedure criteria sheet, 2026–27 season, p. 1 (critical errors, access placement, size, depth and roof removal, internal form, adjacent tooth, surrounding tissue)

Question 2 of 2 · Patient assessment
The finished outline is over the chamber but measures under 2.5 mm at its widest bucco-lingually. How do you read it?

Right answer: Too small

The access size is too small: <2.5 mm at its widest mesio-distally and/or < 2.5 mm at its widest bucco-lingually.

Source: Posterior endodontic procedure criteria sheet, 2026–27 season, p. 1 (critical errors, access placement, size, depth and roof removal, internal form, adjacent tooth, surrounding tissue)

That is the case. Each answer quoted the published source above.

Open M6 step 1 Next case

M6: Endo access, anterior and posterior. Open the lesson step