Microsurgical Apicoectomy: Technique and Indications

When endodontic surgery becomes the correct option compared to orthograde retreatment, how modern microsurgery with MTA and a microscope works, and what success rates reported in the literature really show.

Apicoectomy, or retrograde endodontic surgery, comes into play only after ruling out the possibility of correcting the failure of a previous root canal treatment through non-surgical retreatment. As endodontist Arnaldo Castellucci points out in what's now a classic reference in Italian literature, refinement of orthograde retreatment techniques and instruments has progressively narrowed the cases where the surgical route is truly the only viable option: most chronic apical lesions, including granulomas and cysts, heal with correct non-surgical endodontic therapy, without needing external intervention.

The procedure involves, after local anesthesia, a gingival incision giving access to the facial bone cortex, followed by surgical removal of the pathological root apex along with surrounding infected tissue. The decisive step, from a prognostic standpoint, is retrograde filling: the freshly exposed root tip is sealed with a biocompatible material — today typically Mineral Trioxide Aggregate (MTA) or derived bioceramic materials — through a cavity prepared with dedicated ultrasonic tips, at least 3 millimeters deep and perfectly aligned with the original root canal.

The introduction, starting in the 1990s, of the operating microscope, ultrasonic tips for retrograde preparation and biocompatible materials like MTA has radically transformed the prognosis of this procedure, to the point that we now speak of endodontic microsurgery as a discipline distinct from traditional apicoectomy performed with the naked eye using surgical burs and amalgam. A systematic review and meta-analysis published in 2015 in Clinical Oral Investigations confirms success rates around 90% for the modern technique, consistently higher than traditional approaches with older instrumentation and materials.

In communicating with the patient, an aspect often overlooked concerns the distinction between clinical success and radiographic success: the former coincides with absence of symptoms (no pain, no fistula, adequate chewing function), while the latter requires complete resolution of the periapical lesion visible on radiograph or CBCT, verifiable only 6-12 months after the procedure. The literature reports a success range between 70% and 90% — a wide range reflecting the variability of starting clinical conditions, techniques used, and the criteria by which success itself is defined, which is why it should always be contextualized in informed consent, not reduced to a generic "high success rate".

On Oralzon you'll find instrumentation for endodontic microsurgery: ultrasonic tips for retrograde preparation, bioceramic materials and MTA for filling, along with the operating microscopes needed to perform the procedure to modern practice standards.