Dental Bur Number Decoder

How to read a dental bur number

Burs built to ISO 6360 carry a number in five parts: material, shank, shape, grit, and head diameter. Read left to right and the number describes the instrument completely.

806 314 199 524 014 is an electroplated diamond, FG shank at standard 19 mm, round end taper (long), medium grit with a blue band, 1.4 mm head.

Our supplier prints the ISO number with the European code in brackets and the product reference underneath, so 199(850) / TR-11 / 199-014M are three names for the same instrument. The item number is the shape, the head diameter in tenths of a millimetre, then a grit letter.

Shank codes

ISO	Type	Description	Shank dia.	Length
104	HP	Straight handpiece	2.35 mm	44.5 mm
105	HP	Straight handpiece, extra long	2.35 mm	65.0 mm
204	RA	Right angle / latch type	2.35 mm	22.0 mm
205	RA	Right angle, long	2.35 mm	26.0 mm
313	FG	Friction grip, short	1.6 mm	16.0 mm
314	FG	Friction grip, standard	1.6 mm	19.0 mm
315	FG	Friction grip, long	1.6 mm	21.0 mm
316	FG	Friction grip, extra long / surgical	1.6 mm	25.0 mm

A leading 1 is HP, a leading 2 is RA, a leading 3 is FG. FG will not seat in a latch contra-angle and RA will not fit a high-speed chuck.

Grit codes

ISO	Grit	Microns	Band	Suffix
494	Super fine	15	White	-
504	Extra fine	30	Yellow	EF
514	Fine	50	Red	F
524	Medium	100-120	Blue	M
534	Coarse	135-140	Green	C
544	Super coarse	180	Black	S

Carbides use 000 in the grit position, since blades are not graded by grit. An unbanded diamond is a standard medium.

Diamond shape codes

ISO	Shape	European	Our refs
001	Ball / Round	801	BR-49, BR-45, BR-46, BR-41, BR-40, BR-31, BR-28, BR-26, BR-25, BR-23
002	Round with collar	802	BC-43, BC-42, BC-32, BC-31
010	Inverted cone	805	SI-45, SI-46, SI-47, SI-48
019	Inverted cone with collar	806	DI-41, DI-42
038	Double cone	811	EX-11
039	Double cone, long	811L	EX-12
044	Wheel	818	WR-44
067	Wheel	909	WR-11
068	Wheel	909	WR-13
109	Flat end cylinder, short	835	SF-41, SF-31, SF-42
110	Flat end cylinder, medium	836	SF-20, SF-21, SF-15
111	Flat end cylinder, long	837	SF-11, SF-12, SF-13
130	Ogival end cylinder	885	CP-11, CP-12, CP-13
131	Ogival end cylinder, long	886	-
139	Round end cylinder, short	838	SR-41, SR-31, SR-42
140	Round end cylinder, medium	880	SR-21
141	Round end cylinder, long	881	SR-11, SR-12, SR-13
150	End cut	839	EX-18
164	Pointed cone	852	TC-26
165	Pointed cone	858	TC-21
166	Pointed cone, long	859	TC-27, TC-28, TC-10, TC-11, TC-16
169	Flat end cone, short	845	TF-41
170	Flat end cone	845	TF-42, TF-43, TF-31, TF-23, TF-22
171	Flat end cone	846	TF-20, TF-21
172	Flat end cone, long	847	TF-07, TF-08, TF-09, TF-10, TF-56, TF-14
173	Flat end cone, extra long	848	TF-11, TF-12, TF-13
196	Round end cone, short	849	CR-41, CR-31, CR-42, CR-12, CR-11
197	Round end cone	855	TR-20, TR-21, TR-62, TR-63
198	Round end taper	856	TR-25, TR-24, TR-23
199	Round end taper, long	850	TR-11, TR-12, TR-13, TR-14
200	Round end taper, extra long	850L	TR-15, TR-19
225	Inverted cone	807	SI-50
236	Round end inverted cone	808	EX-41
237	Round end inverted cone, long	808L	EX-31
238	Round end inverted cone, round	808R	EX-20, EX-21, EX-26
239	Pear	-	-
243	Flame	-	-
244	Long flame	-	-
254	Bud	-	-
277	Egg / Football	-	-
697	Round with long neck	801L	BR-L46, BR-L41, BR-L40, BR-L31

US carbide style numbers

American carbide numbers run on a different system from ISO. A 557 is a 557 at every manufacturer, but the number tells you nothing about dimensions on its own. This table maps each style number to its ISO shape, cut, head diameter and head length.

The catalogue does not name carbide head shapes, so only the ISO shape code is given rather than a name inferred from a drawing.

US No.	ISO shape	Cut	Head dia.	Head length	Shanks
1	001	standard blades	0.8 mm	0.8 mm	FG, RA
2	001	standard blades	1.0 mm	1.0 mm	FG, FGXL, RA
3	001	standard blades	1.2 mm	1.2 mm	FG, FGXL, RA
4	001	standard blades	1.4 mm	1.4 mm	FG, FGXL, RA
5	001	standard blades	1.6 mm	1.6 mm	FG, RA
6	001	standard blades	1.8 mm	1.8 mm	FG, FGXL, RA
7	001	standard blades	2.1 mm	2.1 mm	FG, RA
8	001	standard blades	2.3 mm	2.3 mm	FG, FGXL, RA
34	010	standard blades	0.8 mm	0.8 mm	FG, RA
35	010	standard blades	1.0 mm	1.0 mm	FG, RA
36	010	standard blades	1.2 mm	1.2 mm	FG, RA
37	010	standard blades	1.4 mm	1.4 mm	FG, RA
38	010	standard blades	1.6 mm	1.6 mm	FG, RA
39	010	standard blades	1.8 mm	1.8 mm	FG, RA
40	010	standard blades	2.1 mm	2.1 mm	FG, RA
41	010	standard blades	2.3 mm	2.3 mm	FG, RA
56	107	plain cut	0.8 mm	3.8 mm	FG, RA
57	107	plain cut	1.0 mm	4.2 mm	FG, RA
57L	107	plain cut	1.0 mm	6.0 mm	FG, FGXL
58	107	plain cut	1.2 mm	4.2 mm	FG, FGXL, RA
58L	107	plain cut	1.2 mm	6.0 mm	FG, FGXL
59	107	plain cut	1.4 mm	4.5 mm	FG, RA
60	107	plain cut	1.6 mm	4.5 mm	FG, RA
61	107	plain cut	1.8 mm	4.8 mm	FG, RA
62	107	plain cut	2.1 mm	5.0 mm	FG, RA
63	107	plain cut	2.3 mm	5.0 mm	FG, RA
151 (Zekrya surgical)	199	surgical	1.6 mm	11.0 mm	FGL, FGXL, RA
152 (Endo-Z, safe-ended)	219	surgical	1.4 mm	9.0 mm	FGL, FGXL, RA
168	168	plain cut	0.8 mm	3.8 mm	FG, RA
169	168	plain cut	0.9 mm	4.0 mm	FG, RA
170	168	plain cut	1.0 mm	4.2 mm	FG, RA
170L	168	plain cut	1.0 mm	6.0 mm	FG, FGXL
171	168	plain cut	1.2 mm	4.2 mm	FG, RA
171L	168	plain cut	1.2 mm	6.0 mm	FG, FGXL
172	168	plain cut	1.6 mm	4.5 mm	FG, RA
245	139	plain cut	0.9 mm	2.5 mm	FG
329	237	plain cut	0.6 mm	1.7 mm	FG, RA
330	237	plain cut	0.8 mm	1.9 mm	FG, FGXL, RA
331	237	plain cut	1.0 mm	2.0 mm	FG, RA
332	237	plain cut	1.2 mm	2.2 mm	FG, RA
333	237	plain cut	1.4 mm	2.2 mm	FG, RA
556	107	crosscut	0.8 mm	3.8 mm	FG, RA
557	107	crosscut	1.0 mm	4.2 mm	FG, RA
557L	107	crosscut	1.0 mm	6.0 mm	FGXL
558	107	crosscut	1.2 mm	4.2 mm	FG, RA
558L	107	crosscut	1.2 mm	6.0 mm	FGXL
559	107	crosscut	1.4 mm	4.5 mm	FG, RA
560	107	crosscut	1.6 mm	4.5 mm	FG, RA
561	107	crosscut	1.8 mm	4.8 mm	FG, RA
562	107	crosscut	2.1 mm	5.0 mm	FG, RA
563	107	crosscut	2.3 mm	5.0 mm	FG, RA
698	168	crosscut	0.8 mm	3.8 mm	FG, RA
699	168	crosscut	0.9 mm	4.0 mm	FG
700	168	crosscut	1.0 mm	4.2 mm	FG, RA
701	168	crosscut	1.2 mm	4.2 mm	FG, RA
701L	168	crosscut	1.0 mm	6.0 mm	FG, FGXL
702	168	crosscut	1.6 mm	4.5 mm	FG, RA
702L	168	crosscut	1.2 mm	6.0 mm	FG, FGXL
703	168	crosscut	2.1 mm	5.0 mm	FG, RA
704	168	crosscut	2.3 mm	5.0 mm	FG, RA
1156	137	plain cut	0.9 mm	4.0 mm	FG
1157	137	plain cut	1.0 mm	4.2 mm	FG, RA
1158	137	plain cut	1.2 mm	4.2 mm	FG, RA
1159	137	plain cut	1.4 mm	4.5 mm	FG, RA
1160	137	plain cut	1.6 mm	4.5 mm	FG, RA
1161	137	plain cut	1.8 mm	4.5 mm	RA
1556	137	crosscut	0.9 mm	4.0 mm	FG
1557	137	crosscut	1.0 mm	4.2 mm	FG, RA
1557L	137	crosscut	1.0 mm	6.0 mm	FGXL
1558	137	crosscut	1.2 mm	4.2 mm	FG, RA
1558L	137	crosscut	1.2 mm	6.0 mm	FGXL
1559	137	crosscut	1.4 mm	4.5 mm	FG, RA
1560	137	crosscut	1.6 mm	4.5 mm	FG, RA
1700	194	crosscut	1.0 mm	4.0 mm	FG
1700L	194	crosscut	1.0 mm	6.0 mm	FGXL
1701	194	crosscut	1.2 mm	4.2 mm	FG, RA
1701L	194	crosscut	1.2 mm	6.0 mm	FGXL
1702	194	crosscut	1.6 mm	4.5 mm	FG
1957	139	plain cut	1.0 mm	4.2 mm	FG
1958	139	plain cut	1.2 mm	4.2 mm	FG
7004	001	standard blades	1.4 mm	1.4 mm	FG
7005	001	standard blades	1.6 mm	1.6 mm	FG
7006	001	standard blades	1.8 mm	1.8 mm	FG
7007	001	standard blades	2.1 mm	2.1 mm	FG
7008	001	standard blades	2.3 mm	2.3 mm	FG
7104	254	multi-blade finishing	1.4 mm	4.0 mm	FGL
7106	254	multi-blade finishing	1.8 mm	4.5 mm	FGL, RA
7108	254	multi-blade finishing	2.3 mm	5.0 mm	FGL, RA
7204	184	-	1.4 mm	9.5 mm	FGL
7205	184	-	1.6 mm	9.5 mm	FGL
7206	184	-	1.8 mm	9.5 mm	FGL
7404	277	multi-blade finishing	1.4 mm	2.7 mm	FGL
7405	277	multi-blade finishing	1.8 mm	3.5 mm	FGL, RA
7406	277	multi-blade finishing	2.3 mm	3.9 mm	FGL, RA
7702	168	-	1.0 mm	5.5 mm	FG
7703	168	-	1.2 mm	5.5 mm	FG
7801	499	-	0.8 mm	3.5 mm	FG
7802	499	-	1.0 mm	3.5 mm	FG
7803	499	-	1.2 mm	4.0 mm	FG
7901	246	-	0.8 mm	4.0 mm	FG
7902	246	-	1.0 mm	4.0 mm	FG
7903	246	-	1.2 mm	4.5 mm	FG

Common questions

What is a 557 bur?

A 557 is a crosscut straight fissure carbide with a 1.0 mm head diameter and a 4.2 mm head length, ISO shape 107 with 007 crosscut toothing. It is available in FG for a high-speed handpiece and RA for a slow-speed contra-angle. The 556 and 558 are the same shape at 0.8 mm and 1.2 mm.

What is the difference between a 557 and a 57 bur?

Same shape and same dimensions. The 55x series is crosscut, ISO toothing 007, and the 5x series is plain cut, ISO toothing 006. Crosscut blades remove material faster and leave a rougher surface, plain cut is smoother.

What is a 245 bur used for?

A 245 is ISO shape 139 with a 0.9 mm head diameter and 2.5 mm head length, supplied on an FG shank. It is the standard conservative cavity preparation carbide for Class I and Class II preparations.

What does the L mean after a bur number?

Long. A 557L has the same head diameter as a 557 but a longer head, 6.0 mm against 4.2 mm, and is supplied on an extended shank for deeper access.

How do I convert a US carbide number to ISO?

Use the table above, or the decoder at the top of this page. The ISO number is built as material, shank, shape, toothing and head diameter, so a 557 in FG is 500 314 107 007 010.

Reference only. Compiled from ISO 6360 conventions and our supplier’s published specifications. Shape codes and dimensions vary between manufacturers, so verify against the instrument’s own labeling and instructions for use before clinical use. Professional use only.