If a root canal has been recommended, the most useful question to ask is whether the treatment will be performed under a surgical microscope. Long-term success rates are markedly higher with magnification — and the reason is almost always the same canals the naked eye cannot see.
What a root canal is
Inside every tooth is the pulp — the nerve and blood supply. When the pulp is infected by deep decay, a crack, or previous trauma, the two options are extraction or root canal treatment. A root canal removes the infected tissue, shapes and seals the empty space, and preserves the tooth, usually with a crown placed afterwards.
The missed-canal problem
Molars routinely have three or four main canals, with a handful of smaller accessory canals branching off them. At naked-eye magnification, the accessory canals are easy to overlook. A canal that is missed cannot be cleaned, and an uncleaned canal harbours the infection the procedure was meant to resolve. This is the most common reason a root canal fails.
How the microscope changes the procedure
A Zeiss surgical microscope provides up to 25× magnification with coaxial illumination. At that magnification, the floor of the pulp chamber becomes a map: every canal entrance is visible, including the ones tucked under a lip of dentine. The procedure becomes cleaner, more conservative, and more predictable.
- All canal entrances visible, including accessory canals
- Less healthy tooth structure removed during access
- Higher long-term success rate, particularly for upper molars
- Single-visit treatment for most primary cases
When to consider re-treatment
A previously treated tooth that still aches, or that shows infection on a routine X-ray, is rarely a write-off. Microscopic re-treatment locates and treats the canals that caused the original failure. These cases are accepted routinely, and most are resolved without extraction.
Broken instruments and apical surgery
A file that has separated inside a canal during a previous treatment can almost always be retrieved under microscope. When conventional re-treatment is not possible, micro-surgical resection of the root tip (apicoectomy) is a precise, minimally-invasive alternative to extraction.
What it feels like
Computer-guided local anesthesia and modern technique have made root canal treatment comparable to a routine filling. Laughing gas (nitrous oxide) is available for patients who prefer additional relaxation.