HyFlex EDM OGSF Sequence Set, 25mm (4)

HyFlex EDM · OGSF Sequence Set · 25 mm · 4 files

Simple and complex canalsOne protocolCurved canalsShort learning curve

Opener, Glider, Shaper, Finisher: four HyFlex EDM files and one protocol

Coltene built the OGSF sequence on a simple idea: the same four steps, in the same order, every time. Their catalogue: “Evidence shows that by applying checklists and following standard procedures, reproducibility and safety are increased.” So the set is one of each – an Orifice Opener, a Glidepath File, one Shaping File and a Finishing File – with sizes designed with Prof. Eugenio Pedullà.

Speeds from Coltene’s HyFlex EDM OGSF instructions for use (REV-03-2023). Pre-bending from Coltene’s HyFlex EDM OGSF Sequence catalogue (2023).

This pack: Coltene HyFlex EDM OGSF File Sequence Set, 25 mm (Pack of 4) · presterilised
Coltene · Coltène/Whaledent GmbH + Co. KG, Langenau, Germany

What is in the set

One of each file; the Orifice Opener in the set is the 18 mm file, the other three are 25 mm. Refills of each file come in packs of 3.

The defined treatment procedure makes the preparation easy and keeps the learning curve short.

Coltene’s HyFlex EDM OGSF Sequence catalogue (2023), on the OGSF sequence

With just a few peckings, I reach the measured working length without any stops in between, so to speak. Previously, a file had to be inserted into the root canal several times. That is no longer necessary here!

Dr Thomas Rieger, endodontic specialist, Memmingen, Germany – quoted in Coltene’s HyFlex EDM OGSF Sequence catalogue (2025). One clinician’s experience.

The sequence, as Coltene set it out

1  Prepare. After straight-line coronal access, a hand file (up to 20/.02) or a rotary glide path file, and irrigant such as NaOCl placed in the canal.

2  Opener 18/.11, 400 rpm. Creates space for coronal access. “Do not use this file in the curved part of the root canal.” On to the Glider as soon as resistance is felt.

3  Glider 15/.03, 300 rpm. A glide path up to working length. Coltene: “This file is extremely thin and therefore not as breakage resistant as the other HyFlex EDM files.”

4  Shaper 18/.045, 400 rpm. Enlargement up to working length. Back to the previous step as soon as resistance is felt.

5  Finisher 30/.04, 400 rpm. Enlargement up to working length. Larger finishing files if the apex needs them.

Every step, the same handling. “Place the file in the canal without running engine. When the file cannot proceed any further move it back 1mm until it is free of the walls. Then start the engine and proceed forward slowly using tapping movements and without applying pressure.” After each file: check patency with a hand file, keep the canal irrigated and lubricated, and clean the spirals.

Summarised from Coltene’s HyFlex EDM OGSF instructions for use (REV-03-2023). Your clinical judgement governs the case; the instructions for use govern the file.

Why the files behave as they do

›  Cut by spark, not ground. Coltene make HyFlex EDM by electric discharge machining, which they say “creates the unique surface of the new NiTi files and makes the HyFlex EDM files durable and more fracture resistant.”
›  Controlled Memory NiTi. Heat treated so the file is flexible and, in Coltene’s words, pre-bendable like stainless steel – which they describe as “a crucial advantage in curved root canals to avoid the creation of steps.”
›  Three cross-sections on one file. Coltene describe a quadratic cross-section at the tip, trapezoidal in the middle and triangular at the top – a variable design they credit with the file’s breakage resistance.
›  Centred preparation. Coltene: the controlled-memory effect keeps the preparation evenly centred, reducing the risk of ledging or perforation
›  The spirals give before the file does. Coltene’s instructions say the spirals may lengthen in response to force, which “prevents binding blockages to the canal walls and considerably reduces the risk of breakage.” Spirals wound the opposite way mean the file is plastically deformed: do not use it.

Dry and fill to match

The OGSF sequence finishes on 30/.04, and Coltene make paper points and gutta percha at that size: HyFlex EDM paper points 30/.04 (100) and HyFlex EDM gutta percha 30/.04 (60). Coltene’s brochure calls the HyFlex points “ideally matched to the proven nickel-titanium files”.

The sealer goes in with the cone. NeoSEALER® EZFlo is a premixed bioceramic sealer delivered through fine 29-gauge NaviTip™ cannulas – the 25 mm tips suit a 25 mm file set – so sealer goes into the apical third instead of being wiped down the coronal walls. If you work with an epoxy resin sealer, AH Plus® is the one every other is measured against. Resin or bioceramic is a choice of technique rather than a ranking; we carry both. Then a coronal seal: SDR® flow+ Refill, Universal.

Questions we get asked

Is the set enough for a case?
For many, yes – Coltene designed OGSF around “Only one shaping file”. Larger apices take a finishing file after the 30/.04, and refills of each OGSF file are sold in threes.

Which motor settings?
Coltene set 400 rpm and up to 2.5 Ncm for the HyFlex EDM files (the 2025 instructions allow 400–500 rpm on the classic files), and 300 rpm and up to 1.8 Ncm for the glide path files, in continuous rotation on a low-speed contra-angle. Set it in a custom programme on any of the three endo motors we stock: X-Smart® Go · X-Smart® Pro+ · VDW.SILVER® RECIPROC®.

Can I pre-bend them?
Coltene say so: “Like stainless steel files, the HyFlex EDM files can be pre-bent.” They put it down to the Controlled Memory heat treatment of the nickel-titanium.

Are they sterile?
Yes. Coltene: “HyFlex EDM files are supplied presterilized using gamma irradiation.” Sterility holds until the pack is opened or damaged, so a damaged blister is discarded, not used.

Anything to check before use?
Coltene’s instructions carry one patient caution: HyFlex EDM files “contain Nickel and Titanium and should not be used on patient with known allergic sensitivity to these metals.” And before each use, a manual check that the file is correctly fixed in the contra-angle.

OGSF or the classic HyFlex EDM route?
Both use the same EDM files and handling. The classic route runs a 10/.05 glide path and the 25/~ OneFile, with the 20/.05 where needed; OGSF adds a dedicated opener and uses one 18/.045 shaping file. Coltene recommend OGSF as one protocol for simple and complex canals; the choice is yours.

Complete the case

HyFlex EDM OGSF Sequence Set, 25 mm (4) · Orifice Opener 18/.11 · Glidepath File 15/.03 · Shaping File 18/.045 · Finishing File 30/.04 · 400 rpm, glider 300 rpm · presterilised · Coltene · REF 60036142