Fig. 1

Preoperative Radiograph. The tooth #37 had one root with a radiolucency on the apical area. The diagnosis after clinical and radiographic examination was tooth necrosis and asymptomatic apical periodontitis. 

After the rubber isolation, low speed round carbide burs size 018 were used for the caries excavation following by size 010 for locating the orifices. In the final access cavity 4 canal orifices were detected; 3 canals were located distally and had an evident isthmus between them, while one canal mesially was separated by dentin from the others. 

An orifice opener was used and then apical patency was achieved using C-Pilot 08, 10 stainless steel hand files. Working length determination was done with an electronic apex locator. Cleaning and shaping of the root canals were done with rotary instruments until size 25.04 under copious irrigation with 3% NaOCl. EDTA gel was used on the rotary files during the procedure. 

Fig. 2

After checking the fit of gutta-percha master cones, the root canals were dried with paper points and obturation was carried out using an epoxy resin sealer and the continuous wave of condensation technique.  A temporary filling  was placed and a postoperative radiograph was taken. In the next appointment the tooth was restored with a direct composite overlay.  

Fig. 3

Recall Radiograph After 2,5 Years. The patient came to the dental office after 2,5 years due to a fraction in the distal area of the overlay. The recall radiograph revealed a healed periapical region, while the patient reported no symptoms from tooth #37. For the prosthetic rehabilitation of tooth #37 an endocrown restoration was chosen due to the deep pulp chamber, which would provide good retention for this type of restoration. 

Fig. 4

Distal, occlusal, buccal, mesial, and lingual surfaces of the E.max endocrown restoration. Sandblasting of the restoration was done by the laboratory technician. 

Fig. 5

Post-cementation Radiograph Of The Endocrown Restoration. For the cementation of the endocrown restoration a dual-cured, universal, self-adhesive resin cement was used according to the instructions of the manufacturer. 

Fig. 6

Clinical Images Of The Endocrown Restoration After Cementation.

Fig. 7

Ourania Tsiouma

2016: Award of Excellence in the Physiology course from the Laboratory of Experimental Physiology, Medical School, National and Kapodistrian University of Athens.

2015-2019: <<Antonios Papadakis>> scholarship holder during her undergraduate studies.

2019: 1st "Ioannis Karkatzoulis" Prize for the best Oral Presentation in the 19th Pampeloponnesian Dental Congress.

2020: Graduated second with honours from the Dental School of the National and Kapodistian University of Athens, Greece. 

2020–2022: Research Associate in the Department of Endodontics, Dental School, National and Kapodistrian University of Athens. 

2023: Master in Clinical and Surgical Microendodontics, University of Turin, Italy.

Author of scientific articles published in national and international peer-reviewed journals.

Fellow Member of Style Italiano Endodontics.

Private practice focused on Endodontics and Restorative Dentistry in Athens, Greece. 


The C-shaped root canal configuration has a high prevalence rate in mandibular second molars and numerous studies prove that this variation is linked to ethnic diversities. The debriment, obturation and rehabilitation of such cases still remains a clinical challenge. The endocrown restoration seems to be a good solution for the rehabilitation of C-shaped teeth because not only it requires minimal removal of sound tissue for its preparation design, but also can make use of the deep pulp chamber for its retention. However, further studies are needed to confirm that the endocrowns are more beneficial than other restorative approaches for the rehabilitation of C-shaped teeth.


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