Access and anatomy
Access should find canal orifices while conserving tooth tissue. Expect anatomical variation and use magnification or referral when complexity exceeds competence.
Understand
Canal anatomy varies by tooth and patient; missed canals and procedural errors compromise disinfection. Access must balance visibility with preservation of sound tissue.
Assess
Study the pre-operative image for root form, calcification, curvature, restorations and proximity to anatomical structures. Use rubber dam, good illumination and a systematic search for orifices.
Apply
Create a controlled straight-line pathway without unnecessary removal. Stop and refer if anatomy is uncertain or the risk of perforation exceeds competence.
Key distinctions
Anatomical knowledge includes common extra canals, fins, isthmuses and curved roots. A pre-operative image is a two-dimensional projection, so canal overlap can hide complexity. Access design must permit instruments to follow the canal without overcutting tooth. Calcification after trauma or ageing may require magnification and specialist equipment.
Think through a case
A maxillary molar remains symptomatic after treatment and the image suggests untreated anatomy. Revisit access and canal search before assuming the tooth is untreatable.
The distinction to remember
Do not enlarge access blindly in a calcified tooth; perforation risk may warrant magnification and referral.
Test your recall
Why inspect the pre-operative radiograph closely?
Show answer
It informs root number, curvature, calcification and procedural risk.