Five Canals, One Tooth: A Microscope-Assisted Endo-Resto Case 

Fig. 1

A patient presented for evaluation of a mandibular molar with extensive carious involvement.

A preoperative bitewing radiograph revealed caries extending to the pulp chamber. Following clinical and radiographic examination, the tooth was diagnosed with irreversible pulpitis.

The preoperative radiographic assessment was used to evaluate the extent of the carious lesion and the condition of the tooth before treatment.

Fig. 2

Following appropriate anesthesia and rubber dam isolation, access cavity preparation was performed under high magnification.

The access cavity was refined to provide adequate visualization and access to the pulpal floor while maintaining a conservative approach to the remaining tooth structure.

During exploration of the pulpal floor, an additional canal orifice was identified in the distal aspect of the tooth.

In addition to the expected canal anatomy, a middle distal canal was located. This finding increased the total number of canals to five.

The identification of the middle distal canal was a key anatomical finding in this case. Its successful negotiation and subsequent treatment emphasized the importance of carefully examining the pulpal floor and not relying exclusively on the most common anatomical configuration.

Fig. 3

Canal negotiation and shaping

Following canal identification, all five canals were negotiated and prepared.

The canals were shaped to a final preparation size of 25 taper 4%

The shaping protocol was performed with the aim of creating a reproducible canal geometry while facilitating irrigation, disinfection, and subsequent obturation.

The final preparation was standardized across the five canals at size 25 with a 4% taper.

The successful shaping of the complete canal system, including the middle distal canal, allowed for a consistent approach to the subsequent irrigation and obturation procedures.

Fig. 4

Irrigation and activation

Following mechanical preparation, the canals were subjected to a comprehensive irrigation and activation protocol.

Multiple cycles of sonic and ultrasonic activation were used to enhance the distribution and agitation of the irrigating solutions within the prepared canal system.

The objective of the activation protocol was to facilitate the removal of debris and promote effective chemical cleaning of the root canal system, including areas that may be difficult to access through instrumentation alone.

The use of repeated activation cycles was particularly relevant in this case because of the presence of five canals and the additional middle distal anatomy.

Fig. 5

Root canal obturation

Following completion of shaping and irrigation, the canals were obturated using a warm modified obturation technique.

The objective of obturation was to achieve a dense and continuous filling of the prepared root canal spaces while maintaining the established working lengths and canal anatomy.

The obturation procedure was performed for all five canals.

The selected technique allowed for the adaptation of the obturation material to the prepared canal spaces and the three-dimensional anatomy of the root canal system.

Fig. 6

Coronal build-up and margin management

Following completion of the endodontic treatment, the restorative phase was initiated.

The coronal tooth structure was evaluated, and the existing defect was managed to facilitate a predictable definitive restoration.

A coronal build-up was performed to reconstruct the missing tooth structure and establish a suitable foundation for the restorative procedure.

The restorative margin was subsequently elevated to improve the accessibility and management of the deep margin.

The purpose of this step was to create a more accessible and manageable restorative margin while facilitating the subsequent adhesive restorative procedures.

Fig. 7

Bio-base and adhesive overlay

Following the build-up and margin elevation, a bio-base was performed to provide a suitable foundation for the definitive restoration.

The tooth was then prepared for an adhesive overlay.

The definitive restoration was designed to restore the anatomy and function of the treated molar while maintaining a conservative approach to the remaining tooth structure.

The overlay was fabricated using lithium disilicate

The restorative design was selected according to the remaining tooth structure, occlusal requirements, and the need to provide a durable coronal seal.

Fig. 8

Intraoral scanning under rubber dam

An intraoral scan was performed under rubber dam isolation following completion of the coronal build-up and preparation.

Scanning under isolation allowed the restorative workflow to be completed while maintaining the working field under controlled conditions.

The digital impression was used for the fabrication of the definitive overlay.

This approach integrated endodontic isolation and restorative digital workflow into a single treatment sequence.

Fig. 9

Final outcome

The final radiographic and clinical assessment demonstrated the completion of endodontic treatment and definitive restoration of the tooth.

The five root canals, including the middle distal canal, were obturated, and the tooth was restored using a definitive overlay.

The final restoration provided the intended coronal anatomy and function.

Fig. 10

About the author:

Dr Mazen Ahmed