Passive Ultrasonic Irrigation (PUI) and Continuous Wave of Condensation Obturation Technique in a Tooth with Complex RCS Anatomy: A Case Report

relato de caso

Abstract

INTRODUCTION

Nowadays, it is possible to observe some anatomical peculiarities of the Root Canal Systems (RCS). Cone Beam Computed Tomography has proven to be very useful for these observations, allowing for planning with expectations of success in endodontic treatments of complex cases.

Copious irrigation throughout the necessary stages of endodontic therapy is a determining step in the quest for long-term treatment success. Instruments, so necessary for preparing the space and providing an adequate shape for the obturation, are practically ineffective in cleaning the entire Root Canal System, as they cannot shape the branches. The role of irrigating solutions, along with methods that can enhance the removal of the smear layer from the canal walls, is crucial for achieving efficient cleaning of the entire RCS. Passive Ultrasonic Irrigation (PUI) is one of these methods.

The operational mastery of root canal obturation techniques using heated gutta-percha by the dentist is of utmost importance, always accompanied by obturation cements with excellent flow and radiopacity, as these best address the filling of branches.

CASE DESCRIPTION

A 29-year-old female patient, without notable health alterations, sought emergency care for symptomatic irreversible pulpitis of tooth 46, due to a coronal fracture occurring during mastication. At the time, a coronal access to the canals was performed, and some pulp was removed to relieve pain. A temporary dressing was placed with Eugenol and a zinc oxide-eugenol cement with quick setting.

After about a week, the patient consulted an endodontist to plan and execute the endodontic treatment. A pre-operative radiograph was taken using a digital system, and the treatment began.

RESULTS

After removing the sealing material and adjusting the access cavity, maneuvers to locate the canal entrances resulted in identifying one canal in the mesial root and one canal in the distal root, a condition inconsistent with the initial radiographic findings, which suggested the presence of two canals in each root. The accessible canals were worked on with manual "K" files sizes #08, #10, and #15, also performing pre-flaring with NiTi files from the ProTaper Next System (according to the manufacturer's recommendation). A Cone Beam Computed Tomography was requested for possible investigation of the anatomy of the root canals of tooth 46.

The tomographic images showed that, both in the mesial and distal roots, the canals bifurcated slightly below their mid-third, in a very complex anatomical condition, which greatly hindered safe shaping (especially concerning file fracture), ending in an apical delta.

Based on these findings, the defined strategy discussed with the patient was to instrument the accessible canals using the ProTaper Next technique, under copious irrigation with 5.25% Sodium Hypochlorite during the stages. After shaping and immediately before obturation, Passive Ultrasonic Irrigation (PUI) was applied using an Irrisonic E1 tip (HelseDental Technology), energized at minimal power, in each prepared canal as follows: a) 1 minute of energization with 5.25% Sodium Hypochlorite; b) 1 minute of energization with 17% aqueous EDTA solution; c) 1 minute of energization with 5.25% Sodium Hypochlorite. The canals were then dried with absorbent paper points.

The obturation was performed after radiographic verification and selection of the main gutta-percha cones. The obturation cement used was AH Plus (Dentsply/Sirona). The obturation technique employed was the “Continuous Wave of Condensation,” using the E&Q Plus electric heat conductor (Meta). At the end of the process, radiographic examination confirmed effective filling of canal portions not reached by the cutting instruments, up to the apical ends of the root canals, including slight overflows of obturation material.

No postoperative reactions required pain medication. Radiographic control 42 months after the completion of the case shows periapical images of the treated tooth compatible with normality. Clinically, the tooth was asymptomatic.

FINAL CONSIDERATIONS

It is reasonable to conclude that Passive Ultrasonic Irrigation (PUI) enabled satisfactory cleaning of tooth 46 with complex endodontic anatomy. The cleaning achieved and an efficient obturation technique were decisive for the maintenance of the dental element in question.