1. www.comtesfht.cz
Nanostructured titanium for dental
implants
Pavel Šuchmann, COMTES FHT a.s.

2. www.comtesfht.cz
COMTES FHT – brief introduction
 private research institute
 established in 2000 as a small engineering office
(5 engineers)
 currently 75 employees, projects in EU, India,
China, USA etc.

3. www.comtesfht.cz
COMTES FHT - activities
 Development of alloys and their processing technologies (casting,
forming, heat treatment etc.)
 Prototyping, verification of new technologies in field conditions
 Testing of mechanical and thermophysical
properties, measurement of complex materials
data
 Metallographic analyses, fractography etc.

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Dental implants - requirements
 biocompatibility
 high strength and toughness
 high precision of geometry
Most dental implants are made of titanium

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Market situation in titanium dental implants
 Only few titanium allyos are certified on biocompatibility
 High strength of implants is required because of low cross sections
 No strengthening via heat treatment possible
 Limited application of Ti gr. 5 in the last time because of problematic
biocompatibility although the material is certified (contains Al, V)
ASTM grade (W. Nr.) Fe O N C H Al V UTS [MPa]
Ti grade 1 (3.7025) 0.15 0.12 0.05 0.06 0.013 - - 240
Ti grade 2 (3.7035) 0.20 0.18 0.05 0.06 0.013 - - 440
Ti grade 3 (3.7055) 0.25 0.25 0.05 0.06 0.013 - - 540
Ti grade 4 (3.7065) 0.30 0.35 0.05 0.06 0.013 - - 650
Ti grade 5 (3.7165) 0.30 0.20 0.05 0.08 0.015 5.5 – 6.75 3.5 – 4.5 920
Limited options to achieve
strength of > 650 MPa
together with very good
biocompatibility

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Technical approach
 Grain boundary strengthening (using of Hall-Petch relationship)
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Laboratory experiment
Equal Channel Angular
Pressing – ECAP Industrial process
Continuous extrusion on
CONFORM machine

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Nanostructured Ti for high strength applications
 technical approach: strengthening through grain refinement
(Hall-Petch law)
 technology: grain refinement through severe plastic
deformation (SPD) using continuous extrusion on CONFORM
followed by rotary swaging

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Effect on grain size
8
=200 µm; Map3; Step=0.75 µm; Grid600x500
20 mm
Feedstock
Multiple conformed
Swaging (7 mm)

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CONFORM + rotary swaging of Ti gr. 2
 Rm=1000 Mpa (diameter of 5 mm)
 nanostructured Ti gr. 2 reached mechanical properties of
commercial Ti gr. 4 and Ti gr. 5
0,0
5,0
10,0
15,0
20,0
25,0
30,0
0,0
200,0
400,0
600,0
800,0
1000,0
1200,0
Elongation,A5[%]
Rm[MPa],R0.2[MPa]
True strain, φ [-]
Ti GRADE 2
Rp0,2[Mpa] Rm[Mpa]
ASTM Grade
Tensile
strength
Rm (MPa)
Yield
strength
Rp0.2
(MPa)
Elongation
A5(%)
Grade 1 min. 240 min. 170 24
Grade 2 min. 345 min. 275 20
Grade 3 min. 450 min. 380 18
Grade 4 min. 550 min. 483 15
Grade 5 min. 895 min. 828 10
nano Ti gr. 2 1000 950 12

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CONFORM + rotary swaging of Ti gr. 4
 Rm=1200 MPa
 nanostructured Ti gr. 4 has better mechanical properties than
commercial Ti gr.5
ASTM Grade
Tensile
strength
Rm (MPa)
Yield
strength
Rp0.2 (MPa)
Elongation
A5(%)
Grade 1 min. 240 min. 170 24
Grade 2 min. 345 min. 275 20
Grade 3 min. 450 min. 380 18
Grade 4 min. 550 min. 483 15
Grade 5 min. 895 min. 828 10
nano Ti gr. 2 1000 950 12
nano Ti gr. 4 1210 1190 11
0,0
5,0
10,0
15,0
20,0
25,0
30,0
0,0
200,0
400,0
600,0
800,0
1000,0
1200,0
1400,0
Elongation,A5[%]
Rm[MPa],R0.2[MPa]
True strain, φ [-]
Ti GRADE 4
Rp0,2[Mpa] Rm[Mpa]

11. www.comtesfht.cz
Summary
 Nanostructured titanium is a unique opportunity to
improve mechanical properties of dental implants
(no problems with biocompatibility)
 Since 2013 nanostructured Ti made at COMTES FHT
is used for making of special implants
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12. www.comtesfht.cz
Thank you for your attention!
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