Dental Burs Types

Dental Burs Types, Turbine Burs or FG Friction Grip Burs types
30
Jan

How to Differentiate All Dental Burs: Types, Shapes, and ISO Classification

Dental burs are rotary cutting instruments used with dental handpieces to remove tooth structure, shape restorations, and perform surgical or prosthetic procedures. With hundreds of bur shapes, materials, and standards available today, differentiating dental burs can be challenging—even for experienced clinicians and technicians.

This guide explains all dental bur types, based on rotary instrument, material, shape, grit size, and ISO classification, helping you choose the correct bur quickly and confidently.

Dental Burs Types: Complete Classification Guide

In the 1980s, leading international dental organizations unified dental bur identification under standardized nomenclature systems. This resulted in the adoption of ADA Specification No. 23 and ISO standards, which are still used worldwide today.

Understanding these classifications makes purchasing dental burs easier, safer, and more precise.

Dental Burs Classification by Rotary Instrument Type

The first and most fundamental way to differentiate dental burs is by the type of handpiece they are designed to be used with.

Turbine Burs (FG – Friction Grip)

Turbine burs, also known as FG burs, are the smallest dental burs and are used with high-speed dental turbines.

Key characteristics:

  • Shank diameter: 1.6 mm

  • Smooth shank with free end

  • ISO shank length codes start with 3XX

  • Designed for speeds up to 400,000 RPM

These burs are commonly used for cavity preparation, crown preparation, and hard tissue cutting.

Read More About:

  • Difference between Carbide and Diamond Burs
  • Dental Turbine Burs
  • Dental Drills

Contra-Angle Burs (RA – Right Angle)

Contra-angle burs, or RA burs, are used with low- and medium-speed contra-angle handpieces.

Key characteristics:

  • Shank diameter: 2.35 mm

  • Notch at the end of the shank for locking into the handpiece

  • ISO shank length codes start with 2XX

They are widely used for caries removal, finishing, polishing, and prophylaxis.

Straight Handpiece Burs (HP – Handpiece)

HP burs are the largest dental burs and are designed for straight handpieces, used in both clinical and laboratory settings.

Key characteristics:

  • Shank diameter: 2.35 mm

  • ISO shank length codes start with 1XX

These burs are commonly used in prosthetic labs, oral surgery, and heavy material reduction.

Dental Burs Classification by Material

Dental burs are also classified by the material of the working portion, which directly affects cutting efficiency and clinical indication.

Tungsten Carbide Burs (ISO 500)

Tungsten carbide burs replaced older steel burs due to their superior hardness and durability.

Features:

  • Made from tungsten carbide alloy

  • Sharp cutting blades

  • Excellent for precise and controlled cutting

  • ISO designation: 500 series

They are ideal for removing existing restorations, cutting metal, and controlled tooth preparation.

Diamond Burs (ISO 806)

Diamond burs are manufactured by electroplating multilayered diamond particles onto the bur head.

Features:

  • Excellent precision and surface control

  • Available in multiple grit sizes

  • Ideal for ceramics, enamel shaping, and fine finishing

  • ISO designation: 806 series

Dental Burs Classification by Shape

Bur shape is one of the most important and clinically relevant classifications. Each shape is designed for a specific cutting action or anatomical requirement.

Commonly Used Dental Bur Shapes

Round Bur

Ideal for caries removal, surgical access openings, and orientation grooves.

Straight Cylindrical Bur

Used to create flat surfaces and parallel walls.

Curved Cylindrical Bur

Commonly used for occlusal orientation grooves.

Round-End Tapered Bur

Suitable for beveling, crimping, and prosthetic pre-treatments.

Flat-End Tapered Bur

Used to define final margins and create preparation steps.

Inverted Cone Bur

Designed for retentive cavity preparations.

Flame Bur

Indicated for lingual surfaces of incisors and canines.

Wheel Bur

Used for heavy reduction and mechanical retention.

Torpedo Bur

Ideal for creating terminal lines in fixed prosthetics.

Dental Burs Classification by Grit Size

The same bur shape can be produced with different grit sizes, depending on the clinical application.

Diamond burs are identified by color-coded rings on the shank, according to ISO standards.

From coarsest to finest:

  • Extra coarse – aggressive reduction

  • Coarse

  • Medium

  • Fine

  • Extra fine – finishing and polishing

The same bur shape can therefore be used for both initial reduction and final polishing, depending on grit size.

Dental Burs Classification by Diameter (ISO Size)

This classification refers to the maximum diameter of the working portion of the bur.

Using the round bur (ISO shape 001) as an example:

  • Small ISO sizes (e.g. 009) are ideal for detailed work and incipient caries

  • Larger diameters are used for prosthetics and surgical procedures

ISO size directly correlates with the bur’s diameter in millimeters.

Understanding Dental Bur ISO Nomenclature

After standardization, each dental bur can be fully identified using an ISO code, regardless of manufacturer.

Example ISO code:
806.314.001.524.016

This code defines:

  • Material (diamond)

  • Shank type (FG)

  • Bur shape

  • Grit size

  • Working diameter

Understanding this system ensures accurate, brand-independent bur selection.

Conclusion

This comprehensive guide to dental burs types and classification is designed to simplify bur selection and eliminate confusion when purchasing dental burs online. By understanding rotary instrument compatibility, material, shape, grit size, and ISO nomenclature, clinicians and technicians can choose the right bur with confidence.

Frequently Asked Questions About Dental Burs

What are the main types of dental burs?

Dental burs are mainly classified by the handpiece they are used with (FG turbine burs, RA contra-angle burs, and HP straight handpiece burs), as well as by material, shape, grit size, and ISO classification.

What is the difference between FG, RA, and HP dental burs?

FG (friction grip) burs are used with high-speed turbines and have a 1.6 mm shank. RA burs are designed for contra-angle handpieces and have a notched 2.35 mm shank. HP burs are used with straight handpieces and also have a 2.35 mm shank but are longer and unnotched.

How are dental burs classified by ISO standards?

ISO standards classify dental burs by material, shank type, shape, grit size, and working diameter. Each bur receives a unique ISO code that allows universal identification regardless of manufacturer.

What is the difference between carbide and diamond dental burs?

Carbide burs cut using sharp blades and are ideal for controlled cutting and removal of restorations. Diamond burs cut by abrasion and are preferred for shaping enamel, ceramics, and fine finishing.

What do the color rings on diamond burs mean?

The colored ring on a diamond bur indicates grit size. Coarser grits are used for rapid reduction, while finer grits are used for finishing and polishing, according to ISO color-coding standards.