FAQs about burs
What is a sintered diamond bur?
Very simply, a sintered diamond bur is one in which the head of the instrument is made of diamond particles and a binder material. Varenkor employs the “traditional” method of manufacturing which produces a very dense, even wearing and longer lasting matrix.
Some other manufacturers opt for the “induction” method which is a shorter process, generally yielding lesser results.
Some other manufacturers opt for the “induction” method which is a shorter process, generally yielding lesser results.
What is a “traditional” solid sintered diamond bur?
Traditional, Solid Sintering - VARENKOR
Each Varenkor instrument is manufactured through the traditional sintering process, also known as hot pressing. The diamond particles and metallic binder powders are chosen with the finished instrument in mind, i.e., polishing, soft grinding, heavy duty grinding, etc. The binder is mixed with the diamond particles and baked with intense heat and pressure (hot pressing) for several hours. Because no oxygen is present during the baking process, there is no oxidation.
Induction sintering (NOT VARNKOR)
Many manufacturers (NOT VARENKOR) use the shorter “induction” method of sintering. For this process the metallic binders are chosen for their lower melting points. Because both the matrix and the shank are baked together, the binders must melt quickly so the shanks will not melt during the baking process.
Each Varenkor instrument is manufactured through the traditional sintering process, also known as hot pressing. The diamond particles and metallic binder powders are chosen with the finished instrument in mind, i.e., polishing, soft grinding, heavy duty grinding, etc. The binder is mixed with the diamond particles and baked with intense heat and pressure (hot pressing) for several hours. Because no oxygen is present during the baking process, there is no oxidation.
- Man-made diamonds are used to ensure consistently high quality
- Metallic binder powders are chosen according to the final application of the instrument
- Matrixes are made separately from the shanks (solid sintered), and are later welded together
- Sintering is done in closed ovens without the presence of oxygen
- Applied pressure is extremely high resulting in a very dense, even-wearing matrix.
- Sintering process lasts several hours
Induction sintering (NOT VARNKOR)
Many manufacturers (NOT VARENKOR) use the shorter “induction” method of sintering. For this process the metallic binders are chosen for their lower melting points. Because both the matrix and the shank are baked together, the binders must melt quickly so the shanks will not melt during the baking process.
- Metallic binder powders are chosen for their lower melting points
- Burs are baked on the shank (not solid sintered)
- Oxygen is present during the baking process
- Applied pressures are necessarily low
- Baking time is approximately 2 minutes
What Is a Ceramic Bonded bur?
Varenkor ceramic bonded burs are also solid sintered diamond burs, but are manufactured with a porcelain binder rather than a metallic binder. The result is a cooler running, very efficient, virtually vibration free cut. They are recommended for use on all glass materials such as porcelain including ZIRCONIA. They do not last as long as the traditional metallic binder sintered burs, but they may be exactly the right instrument for your use.
What is the difference between the discs?
We offer three types of discs. See a diagram with an explanation.
What is the difference between a hand piece bur (HP) and a friction grip bur (FG)?
A hand piece bur (HP) is one that normally has a 3/32” shank diameter. The diameter and the length of the HP burs can vary for special orders. The maximum rotational speeds normally range from 10,000 to 30,000 RPM depending on the diameter of the head of the instrument.
A friction grip bur (FG) is much smaller than a HP bur and has a much higher rotational speed. The shank diameter is 1.5 mm and the maximum rotational speed is 300,000 RPM. (Our FG burs are not designed for intra-oral use.)
A friction grip bur (FG) is much smaller than a HP bur and has a much higher rotational speed. The shank diameter is 1.5 mm and the maximum rotational speed is 300,000 RPM. (Our FG burs are not designed for intra-oral use.)
What is the difference between traditional and Multizirk friction grip (FG) burs?
Traditional FGs are manufactured through the “traditional” solid sintering method while the Multizirk FGs are manufactured by applying multi-layers of electro-plated diamonds to a pre-form.
What is the cleaning stone, and how do you use it?
Our cleaning stone is an aluminum oxide block that should be used when switching materials so as not to drag contaminants from one material to another, or simply whenever you feel your bur needs cleaning. It’s recommended that you wet the stone before use as this really does offer the best cleaning, but dry works too. This is not a sharpening stone. There is no need to sharpen our burs.
Why does my bur feel like it doesn’t work as well anymore?
This should not happen if you’re using the bur on the recommended material. Our binders are chosen to work with specific materials and those materials should be strong enough to break away the binder in order to expose new diamonds. If your burs feel that they're no longer working well, try running your bur on a harder material for a bit, and then clean it.
Another reason might be that you’re exceeding the recommended RPM. Sintered burs lose efficiency at too great a speed. Slow down and let the diamonds and the hand piece do the work for you.
Another reason might be that you’re exceeding the recommended RPM. Sintered burs lose efficiency at too great a speed. Slow down and let the diamonds and the hand piece do the work for you.
Is the quality of Varenkor instruments guaranteed?
Varenkor instruments are high quality, long wearing, superior performance burs, manufactured in accordance with ISO 9002. All instruments are guaranteed against manufacturer defect.
What is the shank size of the burs? Is it possible to order a different shank size?
The burs shown on this site have a 3/32” (2.336 mm) shank diameter. Other shank sizes are available, but we do not normally hold them in stock unless requested. Please contact us.
Do you sell to distributors?
Yes, we do sell to distributors. Please contact us.
What is the difference between a bur and a drill bit?
A bur and a drill bit are the same things. Different industries refer to them by different names. Sometimes they are referred to as tool bits. They are all rotary instruments designed to be used with an electrically powered apparatus such as a hand piece, lathe or similar.