In this article, A case of a maxillary first molar serving as an abutment to a multi-unit fixed partial denture having a broken instrument in the isthmus between MB1 and MB2 will be discussed.
Clinical examination confirmed the presence of symptomatic apical periodontitis, and the coronal restoration was judged sound by examination using the operating microscope.

CBCT evaluation confirmed absence of apical disease around the DB and palatal roots, therefore microsurgical approach was proposed and executed as a conservative option for treatment.

The microsurgical work flow involved soft tissue access, lesion removal, root-end resection, root-end preparation and root-end filling using premixed Putty Bioceramic.


Mechanically; Microsurgical approach can solve problems related to heavily restored teeth, which would be other-wise compromised by non-surgical approaches.

Biologically; Apical Microsurgery is considered as a single visit approach for management of complex cases of instrument separation having persistent apical periodontitis, with very high success rate.


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