Dentistry requires a large number of specialized tools and equipment. In fact, the prices we pay dentists are for their skills and for the use of the latest tools. One such tool is a dental bur, which is able to cut hard tissues in bones or teeth. A bur is comprised of three parts- a head, neck, and a shank. More information will be found during the course of this write-up.
Various Kinds of Dental Burs
The most commonly used types of dental burs are the diamond burs and the tungsten carbide burs. Among these general categories there are also sub categories for dentists and dental surgeons to order dental burs. Here’s a closer look at both the main categories:
- Diamond – Diamond burs are made from stainless steel frames that are coated in diamond powder that is available in different grits. Dental procedures for which they can be used are dependent on the level of grit in use. The predominant uses of these burs are polishing and precision shaping. Since diamond is one of the hardest materials known to man, it is used to grind porcelain or to cut through zirconia for preparation of crows and veneers. However, compared to the other types of burns, they possess shorter life spans.
- Tungsten Carbide – Being made of tungsten carbide, these burs are thrice as robust as steel. High metal hardness allows them to be used. A Tungsten Carbide bur generally has just carbide in its tip. These tend to build up debris during use. Composite restorations can be filled and trimmed using them.
History of Dental Burs
During the year 1728, hand rotated drills were being first used for root canal procedures. The first machine burs made from steel was rolled out in 1891. Diamond burs were introduced in the 1940’s and carbide burs came to light in the year 1947.
Classification as per Shape of Bur Head
- Tapered Fissure
- Pear Shaped
- Inverted Cone
The most common direction of rotation for dental burs is clockwise. However, there are also burs that rotate in the anticlockwise direction, but these are very few.
Classification as per Hand Piece
This classification was based on the kind of hand pieces they were designed for. The categories are:
- Straight Hand Piece Bur
- Contrangle Bur
Dental Bur Design
Blades of dental burs are mostly in even numbers. The ones used for cavity preparation have 6, 8, or 10 blades. The different parts of dental burs are:
- Bur Blade – These equally spaced projections are present on the bur head and they terminate in cutting edge. The blade consists of two surfaces:
- Rake Face
- Blade Back
- Radial Line – This line connects the centre of the bur and blades
- Chip/Flute Spaces – These depressed areas are present between bur blades
- Rake Angle – It is the angle between the rake face and the radial line. It could be negative, positive, or zero.
- Clearance Angle – The angle between the work, which is the tooth, and the rake face is known as clearance angle
- Land – The plane surface which immediately follows the cutting edge is called land
- Blade Angle – It is the angle formed by the rake face and the land rake face
- Radial Clearance – A curved clearance face is known as radial clearance
The dental bur has to be used at high speed for it to cut the tooth structure in an effective manner. The dentist needs to apply the right amount of pressure on the device. Fracture mechanisms that occur in tooth structures as a result of cutting are of two types- ductile and brittle.
Buy From a Reputed Store
There are many dental stores these days, and more so after the advent of ecommerce. However, dentists must remember never to compromise on product quality and must always purchase dental burs and other restorative equipment from well known stores. Even on the Internet it is possible to know which stores are more popular than the others. There are also plenty of members in dental communities who will be able to guide properly.
Dentists will be happy to know that the dental industry market is expected to grow at 7.8% CAGR by the year 2023, which means there will be better availability of top quality products such as burs. There is tremendous demand for root canal procedures and teeth whitening, which is driving up the demand at present.
Preparation of Cavities
It becomes easy to carry out cavity preparations with the help of Tungsten Carbide burs, especially while removing amalgam restorations. The chances of enamel microstress fractures are pretty high while using large-bladed carbide blurs. Instead of these, small blade carbide blurs that are available at leading dental stores can be used. The purpose here is to penetrate the amalgam and make a circumferential channel along its margin.