Reports & Studies

Piezo technology opens new options in endodontics

Perfectly designed systems for orthograde and retrograde indications

Endodontics means conservation of teeth. The dentist who wants to offer patients the best possible treatment thinks very carefully before recommending implants. Nonetheless, endodontic treatment may still have its challenges, particularly in the case of revisions. Orthograde and retrograde ultrasonic instruments are very useful for resolving problems. Drives with a wide range of power output are available for this field.

Ultrasound based on the piezoelectric effect is best suited for endodontic applications (1, 2). Instruments (inserts) are induced to oscillate in defined, mostly axial movements with the help of excited crystals. Harmonized drives amplify the oscillations to a greater or lesser degree. They can be used very efficiently for orthograde indications and also for surgical indications in bone.

Orthograde ultrasonic treatment

Sensitivity, good lighting and finely adjusted settings are important for orthograde ultrasound. The power required is lower than that for surgical indications and is gradually increased from low values. A dental loupe with 4x to 16x magnification is generally sufficient for all steps with a direct view. If a direct view is not possible, a surgical microscope is the best solution.

In addition to special devices, piezo units that are also used for periodontal debridement are ideal for orthograde ultrasonic treatment (such as W&H Tigon, Tigon+ or Pyon). The power can be adjusted very finely with infinite adjustment and three different treatment modes (Tigon+). Both Tigon models include the 5x ring LED integrated into the handpiece for illumination of the surgical site.

Orthograde variety in endodontics

Figures 1 to 3 show instruments (inserts) of a new, expanded W&H set for orthograde endodontics.

4E Piezo instrument
Fig. 1: The 4E piezo instrument for Tigon/Tigon+/Pyon (W&H) is used for atraumatic preparation of the cavity floor for detection of all root canals with secondary and tertiary dentine formation.
(Fig. 1 - 3: Dr. Nouraie Ashtiani, Bremen)

The set is designed specifically for the above devices and has six slender and practical inserts.

It covers all common indications from exposure of the pulp chamber floor (new: 4E) (Fig. 1) to lateral condensation (2E).

Activation with ultrasound significantly improves the cleaning and disinfection efficiency of endodontic rinsing solutions (3).

The freely oscillating 1E insert has been specifically further developed for this purpose (Fig. 2).

It is flexible enough to bend in curved channels and thus penetrates further apically than rigid instruments.

1E Piezo instrument
Fig. 2: Ultrasound-activated rinsing significantly improves the disinfection effect and thereby the success of the treatment. The advanced 1E piezo instrument follows the course of curved canals.
3E Piezo instrument
Fig. 3: The fine diamond-coated 3E piezo instrument is suitable for procedures such as the exposure of fractured root canal instruments.

A great advantage of the angled piezo inserts is the improved view of the surgical site compared with rotary instruments. For revisions, inserts are available for removing root filler material, making channels accessible (new: 6E), vibrating in or loosening root pins (new: 5E) and circular exposure of fractured root canal instruments (optimized: 3E) (Fig. 3).

Preparation should be performed dry, i.e. without water for irrigation, to ensure an unrestricted view of the preparation site and to prevent interference from reflections (1).

Effective, atraumatic endo-surgery

Many dentists who specialize in implantology are familiar with piezo surgery.

This technology enables extremely effective preparation of bone, particularly with the latest generation of devices such as the W&H Piezomed. Having 24W it offers significantly more power than piezoelectric devices for orthograde endodontics (maximum output of Tigon+: 10 W).

Dr. Nouraie Ashtiani
Fig. 4: Successful endodontic procedures require not only magnification for better vision and good lighting, but also a modern ultrasonic system (in photo: Dr. Nouraie Ashtiani).

The first step using the piezoelectric technology is fast and targeted ablation of the bone over the defect (4, 5). Root tips can also be very effectively bevelled and retrograde cavities can be prepared with a selection of angled or curved-shaft inserts (6). Only one drive unit is required for the complete procedure. The unique automatic instrument detection of the Piezomed also improves clinical safety.

Even with the high effectiveness of the unit soft tissue is protected by the micro-oscillating instrument motion (7, 8). In the field of endosurgery this factor is relevant, for example, for cystectomies, which require histological examination (Fig. 5 and 6). The sterile fluid management of the piezosurgical unit is also very useful.

retrograde endodontics
Fig. 5: The Piezomed unit and matching instrument set is an efficient piezosurgical system for retrograde endodontics.
retrograde endodontics
Fig. 6 For example, it is very effective with bone ablation for cystectomies while protecting the soft tissue. (Photos: Dr. Dragana Gabric, University of Zagreb, Croatia)

Ultrasound, particularly using the piezoelectric principle, has become established for numerous endodontic procedures. While units with lower output power and appropriate instruments are suitable for orthograde indications (such as the new W&H Endo set), the Piezomed piezosurgical system offers greater efficiency and clinical safety for retrograde endosurgical procedures.

Practical orientation with system

W&H, the Austrian dental company, appoints experienced dentists as consultants for the design of the orthograde endodontics set. They include Dr. Andreas Bartols, MA, director of the polyclinic for endodontics at the academy in Karlsruhe and Dr. Nouraie Ashtiani, dentist specializing in endodontics and oral surgery (Bremen). With an internal development system built up over many years W&H guarantees a clear alignment to the daily requirements of the dental practitioner.


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