Figure 1 Initial and final radiographs taken by the referring dentist: A
Radiograph; c) Final radiograph with temporary restoration.
Methods(Differential diagnosis, investigations and treatment)
Radiological and clinical evaluations indicated pulp necrosis along with
chronic apical periodontitis. The patient reported painful sensitivity
to touch and percussion, as well as spontaneous pain. Given the
discharge from both sides of the teeth, vertical root fracture (VRF) and
bilateral maxillary sinus tracts were considered in the differential
diagnosis, with differing prognoses for each condition. Sinus tract
tracing was not possible, as the tract had closed due to the patient’s
prior antibiotic use, which began two weeks before her evaluation. These
antibiotics had been prescribed by the referring dentist following
initial Root Canal Therapy (RCT) (Figure 1C). However, probing depth
assessment revealed no J-shaped lesion, making VRF less likely. Due to
this and the patient’s financial limitations, CT imaging was not
pursued.
The patient underwent a single-visit root canal retreatment as the
first-line approach for a potentially savable tooth. The procedure began
with the administration of local anesthesia using 2% lidocaine and
epinephrine 1:100,000 (Daroupakhsh, Tehran, Iran). The temporary
restoration was carefully removed using a high-speed diamond round bur
number 2 (Jota AG, Rüthi, Switzerland) and a continuous water spray. The
entire process was performed under rubber dam isolation and with a
dental operating microscope (Zumax Medical Co., Suzhou New District,
China) to ensure precision and safety. To prepare the root canals,
gutta-percha was removed with chloroform (Morvabon, Tehran, Iran), gates
glidden drills (number 1, 2, 3), and M3 retreatment rotary files (UDG,
Changzhou, China). The working length of the canals was determined using
an electronic apex locator (Dempex, DEM Ltd., England) and verified
through radiography (Figure 2A). Root canals were prepared using a
crown-down technique with M3 rotary files (UDG, Changzhou, China) up to
size 25 .04, except for the MB2 canal, which was shaped to a smaller
size (size 20 .04). The MB2 canal was found and classified as type 2,
merging with MB1 in its coronal part. Extensive irrigation and passive
ultrasonic activation of sodium hypochlorite and normal saline
alternately were performed during canal instrumentation. After
confirming the cone fit through radiography (Figure 2B), the canals were
dried using sterile paper points (META, South Korea) and obturated with
gutta-percha (META, South Korea) and a bioceramic sealer (NeoSEALER Flo,
Avalon Biomed, Houston, TX, USA) using a warm vertical technique with
FastFill warm obturator (Fast Fill Obturation System, Eighteeth, china)
(Figure 2C) <Figure 2>.