Human teeth details Measurement method and load
(GPa)
(GPa)
(MPa · m0.5 ) (ND: not determined)Remarks
modelling (Y/N)Year/reference number First molar Compressive strength Cusp enamel: 84.1 Side enamel: 77.9 ND
Cusp enamel: 0.384 GPa
Side enamel: 0.372 GPaN 1961 [22 ] Premolar 3-point bending Strain rate: 0.13 mm/min ND Enamel:
= 13
−2
= 200 J · m−2 Dentin:
= 550 J · m−2
= 270 J · m−2 N 1976 [23 ] Two incisors, one molar and one canine MIa
and 500 gf Enamel: 0.7–1.27 Direction of fracture is believed to be dependent on the orientation of the indenter head relative to the local enamel structures N 1981 [24 ] Third molars MMIa MIa
= 2, 3, 5, 10, 20 and 50 N Enamel: 3.37 Dentin: 0.57 Enamel: 80 Dentin: 20 Enamel Parallel—1.3 Perpendicular—0.52 N 1998 [25 ] Incisor NIa
= 300–2500
N Enamel: 4.8 Dentin: 0.8 Enamel: 98 Dentin: 25 ND N 2000 [26 ] Incisor MIa
gf Enamel: 3 Enamel Parallel—0.9 Perpendicular—1.3 Amelogenin nanospheres permit crystallite growth in preferred orientations, but ameloblastin inhibit crystallite growth N 2001 [27 ] First molar NIa
= 20 mN HEa : 0.53 SEa : 3.2 HEa : 14.49 SEa : 77.25 ND Mechanical properties of HEa are significantly lower than those of the SEa N 2004 [16 ] Third molars NIa
: 1000
N
: 300
N Loading:
—4.3
—1.1 Unloading:
—3.9
—1.4 Loading:
—83.4
—39.5 Unloading:
—77.1
—41.2 ND N 2005 [8 ] Premolar NIa Pa = 1–450 mN Enamel TSa : 100–60 CSa : 80–40 ND The top surface is stiffer than the cross-section N 2006 [17 ] Molar CSRa : 0.05, 0.005, and 0.0005 s−1 ND
= 0.05–0.23 GPa
Used TSC model to determine
2006 [18 ] Molar enamel NIa CSRa : 0.05 s−1 For
= 100–2000 nm,
= 5.7–3.6 For
= 100–2000 nm,
= 104–70 ND The decrease in
,
values with depth is speculated to be associated with microstructure evolution that is induced by the indenter tip Used rule of Mixtures to determine
2007 [10 ] Premolar BIa and SIa
mN SEa : 4.49 DEa : 5.01 REa : 4.15 Dry: 4.78 BEa : 5.94 ND HAP nanocrystallites are parallel, diverge from the rod axis by 15–45°, and are at angle of 60° to the central, tail, and edge of the rod, respectively N 2007 [28 ] Molar (hypomineralized) and a sound premolar NIa
= 1–500 mN (SEa )
= 1–200 mN (HEa ) 75–45 as
increased from 0.8–6.1
m
60–80 ND Elastic modulus is highly dependent on the contact size during loading Used FEMa of Spears and the rule of mixtures to determine
2007 [12 ] Third molars NIa LRa : 1 mN/s
: 5 mN
= 4
= 4
= 84.4
= 91.1ND N 2008 [29 ] Third molars MIa :
, 0.25, 0.5, 1, 2, 3, and 5 N. NIa :
= 5 mN Young
= 3.1
= 3.5
= 4.1 Old
= 3
= 3.4
= 4 Young
= 75
= 82
= 87 Old
= 79
= 90
= 100 Young
= 0.95
= 0.88
= 0.88 Old
= 0.88
= 0.73
= 0.67 Brittleness (
m−1 ) Young
= 305
= 375
= 393 Old
= 313
= 582
= 897 N 2008 [30 ] Third molars Cyclic loading
= 3–5 N and 1-2 N for HAP 0.9 (3 times that of HAP) Crack growth occurred primarily along the prism boundaries N 2008 [31 ] Defective premolars, sound premolars NIa
mN
: 10.9
: 2.6ND HAP nanocrystals make 33° angle with the loading direction Used a SMPCSa model to determine
2008 [13 ] Third molar MIa
= 160 gf Enamel: 3.5 ND N 2008 [32 ] Third molar NIa with spheroconical tip
= 5 and 11 mN Enamel: 123 ND
: 1.6 GPa and
: 0.6% at a
of 250 nm and a total penetration depth of 7 nmN 2009 [33 ] Third molars Cyclic loading
= 3–6 N
= 90
= 70
= 2.11
= 1.17
in the forward direction: 4 J/m2
in the forward direction: 10 J/m2 N 2009 [34 ] Molar MIa at 0.98, 1.96, 2.94, 4.9, and 9.8 N 3.33, 3.51, 3.22, 3.31 and 3.22 0.85, 0.87, 0.88, 0.94, and 0.98 N 2010 [35 ] Incisors NIa :
= 500
N Enamel rod: head—5.01 tail—4.52 axial sec—4.58 Enamel rod: head—102.56 tail—97.3 axial sec—97.72 ND
: head—0.087 tail—0.094 axial sec—0.108N 2011 [36 ] Molars NIa
= 2 mN E : 7D : 1E : 95D : 19ND Cracks in the DEJ travelled along structures with dentin characteristics N 2011 [4 ]