Retreatment with ultrasound.
Case of retreatment with ukltrassom in which the presence of resin inside the root canal made its emptying difficult. Patient sought the endodontic specialization clinic with symptomatic apical periodontitis and treated canal. During the emptying of the canal, there was great difficulty in the cervical third of the distal canal due to the presence of hardened material, compatible with resin. Moderate force was then applied with diamond ultrasonic tips, larger at the beginning and smaller in the apical third, until the instrument was successfully passed through the foramen.
Case conducted by the student Camila Soares from the endodontics specialization course at HPG Brasília.
Ultrasound in endodontics
The use of ultrasound devices in dentistry has become very widespread in recent times. In endodontics, there are certainly multiple benefits in an attempt to optimize, simplify and increase the efficiency of the chemical-mechanical preparation of the root canal system.
The biological effects of ultrasound can cause local tissue, cellular and structural changes. These effects come from heat generation, acoustic current production, and cavitation produced during its use.
Types of Ultrasound
First of all, it is important to talk about the different types of ultrasound. The production of ultrasonic energy for dentistry can be done by different transducer systems: the magnetostrictive and the piezoelectric.
The magnetostrictive system was the first ultrasonic vibration generation system used in dentistry. In this system, vibration is generated by applying an electric current to juxtaposed metal plates. In this way, the energy causes the plates to vibrate and is then transferred to an ultrasound tip or insert, which in turn will move. Because of this, this system generates a lot of heat during use.
In the evolutionary search for a more adequate system for dental use, the ultrasonic technology started to use the so-called piezoelectric system. In this system, the vibration results from the application of an electric field on quartz crystals or tourmaline. These crystals when exposed to an alternating electric field undergo variations in their thickness, expanding and contracting.
Thus, these expanding and contracting movements generate ultrasonic sound waves that can be harnessed to produce vibration. Therefore, each transducer has a different resonance frequency.
The thinner the quartz crystal, the higher its vibration frequency. Most piezoelectric ultrasonic devices available on the market work at frequencies above 30,000Hz. In short, ultrasonic frequency is defined as the number of movements performed in a given interval. Frequency should not be confused with power. Thus, ultrasonic power is related to the amplitude of the motion produced.
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Piezoelectric devices
In non-surgical -conventional- piezoelectric ultrasound devices (figure 1), available in the market today, it is possible to adjust the power but not the vibration frequency. Therefore, as the power increases, the amplitude of the oscillation tends to increase as well.
These devices are more precise in cutting than magnetostrictive devices, while generating less heat and being more biologically compatible. In addition, they can be used in microscopic endodontic surgery, as they allow cutting of hard tissue, such as dentin and bone, without damaging the soft tissue.
Use of Ultrasound in Endodontics
The frequent occurrence of problems in the clinic such as instrument fractures, root perforations, zipper formations, inadequate and non-uniform wear within the root canals, allow us to use ultrasonic inserts precisely to solve these problems.
The development of new ultrasonic inserts (figure 2) allowed their efficient and safe use to assist in the refinement and access to the pulp chamber. In addition, it is possible to use them in other procedures, such as
- Removal of pulpal nodules and dentin at the entrance of root canals;
- Removal of the temporary coronary seal, carious tissues and restorative materials;
- Isthmus preparation, removal of intraradicular retainers, fixed prostheses and fractured instruments;
- Ultrasonic activation of irrigating solutions;
- Optimizing the diffusion of intracanal medications into the dentinal tubules;
- Endodontic obturation and debugging;
- Osteotomy;
- Root resection;
- Retropreparation and placement of the retroobturator material into the retroprepared cavity.
- Retreatment with ultrasound
The association of microscopy with ultrasound optimizes the results of endodontic treatments, and has been called microsonics (microendodontics withultrasound). Knowledge of the internal anatomy, as well as its diversities, is of paramount importance for successful endodontic treatment.
Finally, technologies such as ultrasound, visual magnification, increased brightness, and safe grinding of dental structures. This results in an endodontic treatment of excellence. Retreatment with ultrasound.
Prof. Milena Perraro Martins, dentalcremer.com.br
https://ferrariendodontia.com.br/retratamento-retentor-fibra/
