Burs are a vital instrument for dentists that come in a range of styles, shapes, and sizes. Constructed of various materials, these rotary cutters are used to carve away tooth material, prepare teeth for restorations, and even buff out teeth.
Determining the type of bur used is completed by measuring the shank size, head size, and head shape. Most commonly seen is a 2.35 mm (3/32 inch) shank size, although several others include 1.6 mm (1/16 inch), 1.0 mm (3/64 inch), and 0.8 mm (1/32 inch) as well. The head size is calculated using the diameter of the flutes used to cut, commonly appearing as 2.5 mm, 3.0 mm, 4.0 mm, and 5.0 mm in widths. The form of the head is identified by flutes arranged in a configuration that could be anything from a ball shape to inverted cone, needle to pear, and flame to taper forms.
Varying from carbon steel to tungsten carbide, burs come in a variety of materials to suit different tasks. Carbon steel is the most affordable and can be used for basic projects, while chrome steel is slightly more expensive but better suited for delicate work. The priciest option, tungsten carbide, is reserved for more challenging applications.
From high-speed handpieces to low-speed handpieces and dental drills, there are diverse tools to which burs can be attached depending on the material that needs to be cut. For hard materials, such as tooth enamel, high-speed handpieces are a must while for softer components, such as dentin, the ideal accompaniment comes in the form of low-speed handpieces. Dental drills, on the other hand, are called upon when holes need to be created in a tooth.
At a dizzying 30,000 to 40,000 rotations-per-minute, burs spin with unfettered speed. As they traverse the tooth, the bur’s cutting flutes chisel away miniscule portions of its structure.
Tooth structure can often require trimming for a myriad of purposes—from readying surfaces for dental fillings, to carving out cavities for crowns, and even eliminating damaged areas. Burs stand at the ready to perform these tasks, adeptly shaping enamel and sculpting smooth borders. Further, these specialized tools are employed to give edges a glimmering finish.
An array of sizes and shapes of burs exist, each ideally suited for a particular purpose. Therefore, it is essential to select the correct one for the task at hand.
Cavities requiring fillings can be either chiseled out or drilled, with the type of bur used depending on the size and shape that needs to be crafted.
For teeth requiring round fillings, like amalgam fillings, ball burs are often employed to categorize their cavities. For those requiring oval or oblong fillings, like composite resin fills, cone burs are typically the go-to choice for coordinating the concave shape.
In anticipation of placing a dental crown, it is important to choose the correct bur for optimal surface preparation. Variations are contingent on the material of which the crown is comprised.
For metal crowns, chisel burs are the go-to tool for preparing surfaces. On the other hand, diamond burs are most commonly employed for getting surfaces ready for ceramic or porcelain crowns.
When teeth have been affected by damage, a bur is often employed to eradicate the affected structure. Depending on the degree of harm, the corresponding type of bur should be selected.
Damage, whether small chips and cracks or wider cavities, can be addressed through the use of ball and cone burs. The former can be applied for more concentrated removal of these issues, while the latter is better for larger-scale adjustments.
Perfecting and Enhancing
To give surfaces a sleek and refined finish, burs may be utilized to smooth them and fashion margins in the desired shape. Depending on the prominence of the surface, a specific bur should be chosen.
When it comes to creating a smooth surface, cone burs come to mind. For adding a polished look to edges, ball burs are the way to go.
Post time: 2023-06-23