Research progress in tribological property of dental ceramics
Lei LEI1, Yuchi WU1, Zijin CHENG1, Li LIU2, Jing ZHENG1,*()
1 Tribology Research Institute, Key Laboratory of Advanced Technologies of Materials(Ministry of Education), Southwest Jiaotong University, Chengdu 610031, China 2 Department of Stomatology, Southwest Jiaotong University Hospital, Chengdu 610031, China
Ceramics are widely used as dental restorative materials because of their superior wear resistance, chemical stability, biocompatibility, and aesthetic features. In this paper, the chemical compositions, microstructures and mechanical properties of dental ceramics were introduced, based on the wear mechanisms of typical dental ceramics and their abrasiveness with opposing human teeth, the main progress concerning the tribological performance optimization of dental ceramics were summarized, and it was pointed out that the mismatch of tribological properties between ceramics and human teeth seriously restricts the clinical application of dental ceramics. Then the in vitro test methods of tribological properties of dental ceramic materials are analyzed and summarized from the aspects of laboratory test medium, friction pair, load, displacement and cycle times. Finally, the future development trends of dental ceramics were discussed from the perspective of bionic tribology. It was pointed out that bionic design of ceramic matrix composites is a promising strategy for overcoming the mismatch of tribological property between dental ceramic restorations and human teeth.
NANCI A . Ten Cate's oral histology[M]. Amsterdam: Elsevier, 2012: 1.
2
XIA J , TIAN R , HUA L C , et al. Enamel crystallite strength and wear: nanoscale responses of teeth to chewing loads[J]. Journal of the Royal Society Interface, 2017, 14 (135): 1- 8.
ZHANG Z K , YU G Y , XU T . Practice of stomatology[M]. Beijing: People's Medical Publishing House, 2009: 500- 527.
4
ZHOU Z R , ZHENG J . Tribology of dental materials: a review[J]. Journal of Physics D, 2008, 41 (11): 113001.
doi: 10.1088/0022-3727/41/11/113001
5
HO G W , MATINLINNA J P . Insights on ceramics as dental materials. part Ⅰ: ceramic material types in dentistry[J]. Silicon, 2011, 3 (3): 109- 115.
doi: 10.1007/s12633-011-9078-7
6
KRUZIC J J , ARSECULARATNE J A , TANAKA C B , et al. Recent advances in understanding the fatigue and wear behavior of dental composites and ceramics[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2018, 88, 504- 533.
doi: 10.1016/j.jmbbm.2018.08.008
7
ZARONE F , RUSSO S , SORRENTINO R . From porcelain-fused-to-metal to zirconia: clinical and experimental considerations[J]. Dental Materials, 2011, 27 (1): 83- 96.
doi: 10.1016/j.dental.2010.10.024
8
GUO J , TIAN B , WEI R , et al. Investigation of the time-dependent wear behavior of veneering ceramic in porcelain fused to metal crowns during chewing simulations[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2014, 40, 23- 32.
doi: 10.1016/j.jmbbm.2014.08.006
9
STAWARCZYK B , LIEBERMANN A , EICHBERGER M , et al. Evaluation of mechanical and optical behavior of current esthetic dental restorative CAD/CAM composites[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2015, 55, 1- 11.
10
YU P , XIONG Y , ZHAO P , et al. On the wear behavior and damage mechanism of bonded interface: ceramic vs resin composite inlays[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2020, 101, 103430.
doi: 10.1016/j.jmbbm.2019.103430
11
HEINTZE S D , CAVALLERI A , FORJANIC M , et al. Wear of ceramic and antagonist-a systematic evaluation of influencing factors in vitro[J]. Dental Materials, 2008, 24 (4): 433- 449.
doi: 10.1016/j.dental.2007.06.016
12
KRAMER N , KUNZELAMNN K H , TASCHNER M , et al. Antagonist enamel wears more than ceramic inlays[J]. Journal of Dental Research, 2006, 85 (12): 1097- 1100.
doi: 10.1177/154405910608501206
13
MUNDHE K , JAIN V , PRUTHI G , et al. Clinical study to evaluate the wear of natural enamel antagonist to zirconia and metal ceramic crowns[J]. The Journal of Prosthetic Dentistry, 2015, 114 (3): 358- 363.
doi: 10.1016/j.prosdent.2015.03.001
14
CUYA J L , MANNA A B , LIVI K J , et al. Nanoindentation mapping of the mechanical properties of human molar tooth enamel[J]. Archives of Oral Biology, 2002, 47 (4): 281- 291.
doi: 10.1016/S0003-9969(02)00006-7
15
HE L H , SWAIN M V . Understanding the mechanical behaviour of human enamel from its structural and compositional characteristics[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2008, 1 (1): 18- 29.
doi: 10.1016/j.jmbbm.2007.05.001
16
SAKAGUCHI R L , POWERS J M . Craig's restorative dental materials[M]. Philadelphia: Mosby Elsevier, 2012: 16.
17
YAHYAZADEHFAR M , BAJAJ D , AROL D D . Hidden contributions of the enamel rods on the fracture resistance of human teeth[J]. Acta Biomaterialia, 2013, 9 (1): 4806- 4814.
doi: 10.1016/j.actbio.2012.09.020
18
CESAR P F , YOSHIMURA H N , MIRANDA J W G , et al. Correlation between fracture toughness and leucite content in dental porcelains[J]. Journal of Dentistry, 2005, 33 (9): 721- 729.
doi: 10.1016/j.jdent.2005.02.001
19
GE C , GREEN C C , SEDERSTROM D , et al. Effect of porcelain and enamel thickness on porcelain veneer failure loads in vitro[J]. The Journal of Prosthetic Dentistry, 2014, 111 (5): 380- 387.
doi: 10.1016/j.prosdent.2013.09.025
20
HOMSY F , EID R , EL GHOUL W , et al. Considerations for altering preparation designs of porcelain inlay/onlay restorations for nonvital teeth[J]. Journal of Prosthodontics, 2015, 24 (6): 457- 462.
doi: 10.1111/jopr.12279
21
JAGER N D , FEILZER A J , DAVIDSON C L . The influence of surface roughness on porcelain strength[J]. Dental Materials, 2000, 16 (6): 381- 388.
doi: 10.1016/S0109-5641(00)00030-0
22
SHI J Y , LI X , NI J , et al. Clinical evaluation and patient satisfaction of single zirconia-based and high-noble alloy porcelain-fused-to-metal crowns in the esthetic area: a retrospective cohort study[J]. Journal of Prosthodontics, 2016, 25 (7): 526- 530.
doi: 10.1111/jopr.12344
23
ZHANG G , YAO B , GAO H , et al. Nanomechanics properties of feldspathic dental ceramics[J]. Journal of Computational and Theoretical Nanoscience, 2008, 5 (8): 1493- 1496.
doi: 10.1166/jctn.2008.808
24
GONZAGA C C , YOSHIMURA H N , CESAR P F , et al. Subcritical crack growth in porcelains, glass-ceramics, and glass-infiltrated alumina composite for dental restorations[J]. Journal of Materials Science Materials in Medicine, 2009, 20 (5): 1017- 1024.
doi: 10.1007/s10856-008-3667-z
25
GUAZZATO M , ALBAKRY M , RINGER S P , et al. Strength, fracture toughness and microstructure of a selection of all-ceramic materials part Ⅰ: pressable and alumina glass-infiltrated ceramics[J]. Dental Materials, 2004, 20 (5): 441- 448.
doi: 10.1016/j.dental.2003.05.003
26
GUESS P C , SCHULTHEIS S , BONFANTE E A , et al. All-ceramic systems: laboratory and clinical performance[J]. Dental Clinics of North America, 2011, 55 (2): 333- 352.
doi: 10.1016/j.cden.2011.01.005
27
PENG Z , IZZAT A R M , ZHANG Y , et al. Wear behavior of pressable lithium disilicate glass ceramic[J]. Journal of Biomedical Materials Research: Part B, 2016, 104 (5): 968- 978.
doi: 10.1002/jbm.b.33447
28
RITZBERGER C , SCHWEIGER M , HÖLAND W . Principles of crystal phase formation in Ivoclar Vivadent glass-ceramics for dental restorations[J]. Journal of Non-Crystalline Solids, 2016, 432, 137- 142.
doi: 10.1016/j.jnoncrysol.2015.04.034
29
SANTOS M J M C , COSTA M D , RUBO J H , et al. Current all-ceramic systems in dentistry: a review[J]. Compendium of Continuing Education in Dentistry, 2015, 36 (1): 31- 37.
30
BONA A D , MECHOLSKY J J , BARRETT A A , et al. Characterization of glass-infiltrated alumina-based ceramics[J]. Dental Materials, 2008, 24 (11): 1568- 1574.
doi: 10.1016/j.dental.2008.06.005
31
SEGHI R R , DENRY I L , ROSENSTIEL S F . Relative fracture toughness and hardness of new dental ceramics[J]. The Journal of Prosthetic Dentistry, 1995, 74, 145- 150.
doi: 10.1016/S0022-3913(05)80177-5
32
WAGNER W C , CHU T M . Biaxial flexural strength and indentation fracture toughness of three new dental core ceramics[J]. Journal of Prosthetic Dentistry, 1996, 76 (2): 140- 144.
doi: 10.1016/S0022-3913(96)90297-8
33
ERSU B , YUZUGULLU B , RUYA Y A , et al. Surface roughness and bond strengths of glass-infiltrated alumina-ceramics prepared using various surface treatments[J]. Journal of Dentistry, 2009, 37 (11): 848- 856.
doi: 10.1016/j.jdent.2009.06.017
34
CHRISTEL P , MEUNIER A , HELLER M , et al. Mechanical properties and short-term in vivo evaluation of yttrium-oxide-partially-stabilized zirconia[J]. Journal of Biomedical Materials Research, 1989, 23 (1): 45- 61.
doi: 10.1002/jbm.820230105
35
DENRY I , KELLY J . State of the art of zirconia for dental applications[J]. Dental Materials, 2008, 24 (3): 299- 307.
doi: 10.1016/j.dental.2007.05.007
36
GUAZZATO M , ALBAKRY M , RINGER S P , et al. Strength, fracture toughness and microstructure of a selection of all-ceramic materials. part Ⅱ. zirconia-based dental ceramics[J]. Dental Materials, 2004, 20 (5): 449- 456.
doi: 10.1016/j.dental.2003.05.002
37
MCLAREN E A , GIORDANO R . Ceramics overview: classification by microstructure and processing methods[J]. Cosmetic Dentistry, 2015, 1, 18- 27.
38
RAIGRODSKI A J . Contemporary materials and technologies for all-ceramic fixed partial dentures: a review of the literature[J]. The Journal of Prosthetic Dentistry, 2004, 92 (6): 557- 562.
doi: 10.1016/j.prosdent.2004.09.015
39
ZHANG F , SPIES B C , VLEUGELS J , et al. High-translucent yttria-stabilized zirconia ceramics are wear-resistant and antagonist-friendly[J]. Dental Materials, 2019, 35 (12): 1776- 1790.
doi: 10.1016/j.dental.2019.10.009
40
ZHANG Y , LAWN B R . Novel zirconia materials in dentistry[J]. Journal of Dental Research, 2017, 97 (2): 140- 147.
41
DELLA B A , CORAZZA P H , ZHANG Y . Characterization of a polymer-infiltrated ceramic-network material[J]. Dental Materials, 2014, 30 (5): 564- 569.
doi: 10.1016/j.dental.2014.02.019
42
FACENDA J C , BORBA M , CORAZZA P H . A literature review on the new polymer-infiltrated ceramic-network material(PICN)[J]. Journal of Esthetic and Restorative Dentistry, 2018, 30 (4): 281- 286.
doi: 10.1111/jerd.12370
43
HE L H , SWAIN M . A novel polymer infiltrated ceramic dental material[J]. Dental Materials, 2011, 27 (6): 527- 534.
doi: 10.1016/j.dental.2011.02.002
44
LI J , CUI B C , LIN Y H , et al. High strength and toughness in chromatic polymer-infiltrated zirconia ceramics[J]. Dental Materials, 2016, 32 (12): 1555- 1563.
doi: 10.1016/j.dental.2016.09.003
45
LI J , ZHANG X H , CUI B C , et al. Mechanical performance of polymer-infiltrated zirconia ceramics[J]. Journal of Dentistry, 2017, 58, 60- 66.
doi: 10.1016/j.jdent.2017.01.008
46
LI S , ZHAO Y , ZHANG J F , et al. Machinability of poly(methyl methacrylate) infiltrated zirconia hybrid composites[J]. Materials Letters, 2014, 131, 347- 349.
doi: 10.1016/j.matlet.2014.06.021
47
SWAIN M V , COLDEA A , BILKHAIR A , et al. Interpenetrating network ceramic-resin composite dental restorative materials[J]. Dental Materials, 2016, 32 (1): 34- 42.
doi: 10.1016/j.dental.2015.09.009
48
NAKAMURA Y , YAMAMOTO T , SHIIGETA Y , et al. In vitro investigation of human enamel wear by dental porcelain[J]. Bio-medical Materials and Engineering, 2019, 30 (4): 365- 374.
doi: 10.3233/BME-191059
49
NAKASHIMA J , TAIRA Y , SAWASE T . In vitro wear of four ceramic materials and human enamel on enamel antagonist[J]. European Journal of Oral Sciences, 2016, 124 (3): 295- 300.
doi: 10.1111/eos.12272
50
YU H Y , CAI Z B , REN P D , et al. Friction and wear behavior of dental feldspathic porcelain[J]. Wear, 2006, 261 (5/6): 611- 621.
51
ARSECULARATNE J A , DINGELDEIN J P , HOFFMAN M . An in vitro study of the wear mechanism of a leucite glass dental ceramic[J]. Biosurface and Biotribology, 2015, 1 (1): 50- 61.
doi: 10.1016/j.bsbt.2015.02.004
52
DUPRIEZ N D , VON K A K , KUNZELMANN K H . A comparative study of sliding wear of nonmetallic dental restorative materials with emphasis on micromechanical wear mechanisms[J]. Journal of Biomedical Materials Research: Part B, 2015, 103 (4): 925- 934.
doi: 10.1002/jbm.b.33193
53
THEOCHAROPOULOS A , CHEN X , HILL R , et al. Reduced wear of enamel with novel fine and nano-scale leucite glass-ceramics[J]. Journal of Dentistry, 2013, 41 (6): 561- 568.
doi: 10.1016/j.jdent.2013.02.006
54
GALI S , RAVIKUMAR K . Zirconia toughened mica glass ceramics for dental restorations: wear, thermal, optical and cytocompatibility properties[J]. Dental Materials, 2019, 35 (12): 1706- 1717.
doi: 10.1016/j.dental.2019.08.112
55
KALIN M , HOCKEY B , JAHANMIR S . Wear of hydroxyapatite sliding against glass-infiltrated alumina[J]. Journal of Materials Research, 2003, 18 (1): 27- 36.
doi: 10.1557/JMR.2003.0005
56
KALIN M , JAHANMIR S , DRAZIC G . Wear mechanisms of glass-infiltrated alumina sliding against alumina in water[J]. Journal of the American Ceramic Society, 2005, 88 (2): 346- 352.
doi: 10.1111/j.1551-2916.2005.00051.x
57
KALIN M , JAHANMIR S , IVES L K . Effect of counterface roughness on abrasive wear of hydroxyapatite[J]. Wear, 2002, 252 (9/10): 679- 685.
58
LIN W , LIU Y H , SI W J , et al. Friction and wear behaviors of dental ceramics against natural tooth enamel[J]. Journal of the European Ceramic Society, 2012, 32 (11): 2599- 2606.
doi: 10.1016/j.jeurceramsoc.2012.03.021
59
XU Z , YU P , AROLA D D , et al. A comparative study on the wear behavior of a polymer infiltrated ceramic network(PICN) material and tooth enamel[J]. Dental Materials, 2017, 33 (12): 1351- 1361.
doi: 10.1016/j.dental.2017.08.190
60
SANTOS F , BRANCO A , POLIDO M , et al. Comparative study of the wear of the pair human teeth/Vita Enamic® vs commonly used dental ceramics through chewing simulation[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2018, 88, 251- 260.
doi: 10.1016/j.jmbbm.2018.08.029
61
BORRERO-LOPEZ O , GUIBERTEAU F , ZHANG Y , et al. Wear of ceramic-based dental materials[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2019, 92, 144- 151.
doi: 10.1016/j.jmbbm.2019.01.009
62
FIGUEIREDO-PINA C G , MONTEIRO A , GUEDES M , et al. Effect of feldspar porcelain coating upon the wear behavior of zirconia dental crowns[J]. Wear, 2013, 297 (1/2): 872- 877.
63
ABOUSHAHBA M , KATAMISH H , ELAGROUDY M . Evaluation of hardness and wear of surface treated zirconia on enamel wear: an in-vitro study[J]. Future Dental Journal, 2018, 4 (1): 76- 83.
doi: 10.1016/j.fdj.2017.10.001
64
YU P , XU Z , AROLA D D , et al. Effect of acidic agents on the wear behavior of a polymer infiltrated ceramic network(PICN) material[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2017, 74, 154- 163.
doi: 10.1016/j.jmbbm.2017.06.001
65
SILVA C S , HENRIQUES B , NOVAES D O A P , et al. Micro-scale abrasion and sliding wear of zirconium-lithium silicate glass-ceramic and polymer-infiltrated ceramic network used in dentistry[J]. Wear, 2020, 448/449, 203214.
doi: 10.1016/j.wear.2020.203214
66
CHOI J W , BAE I H , NOH T H , et al. Wear of primary teeth caused by opposed all-ceramic or stainless steel crowns[J]. The Journal of Advanced Prosthodontics, 2016, 8 (1): 43- 52.
doi: 10.4047/jap.2016.8.1.43
67
SOUZA J C M , SILVA C S , CARAM S J , et al. Wear behavior of dental glass-ceramics: a scoping review on the damage of opposing tooth enamel surfaces[J]. Biotribology, 2020, 21, 100116.
doi: 10.1016/j.biotri.2020.100116
68
JANG Y S , NGUYEN T T , KO Y H , et al. In vitro wear behavior between enamel cusp and three aesthetic restorative materials: zirconia, porcelain, and composite resin[J]. The Journal of Advanced Prosthodontics, 2019, 11 (1): 7- 15.
doi: 10.4047/jap.2019.11.1.7
69
GOU M , CHEN H , KANG J , et al. Antagonist enamel wear of tooth-supported monolithic zirconia posterior crowns in vivo: a systematic review[J]. The Journal of Prosthetic Dentistry, 2019, 121 (4): 598- 603.
doi: 10.1016/j.prosdent.2018.06.005
70
AMER R , KURKLU D , KATEEB E , et al. Three-body wear potential of dental yttrium-stabilized zirconia ceramic after grinding, polishing, and glazing treatments[J]. The Journal of Prosthetic Dentistry, 2014, 112 (5): 1151- 1155.
doi: 10.1016/j.prosdent.2013.12.021
71
BUCIUMEANU M , QUEIROZ J R C , MARTINELLI A E , et al. The effect of surface treatment on the friction and wear behavior of dental Y-TZP ceramic against human enamel[J]. Tribology International, 2017, 116, 192- 198.
doi: 10.1016/j.triboint.2017.07.016
72
CHONG B J , THANGAVEL A K , ROLTON S B , et al. Clinical and laboratory surface finishing procedures for zirconia on opposing human enamel wear: a laboratory study[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2015, 50, 93- 103.
doi: 10.1016/j.jmbbm.2015.06.007
73
JANYAVULA S , LAWSON N , CAKIR D , et al. The wear of polished and glazed zirconia against enamel[J]. The Journal of Prosthetic Dentistry, 2013, 109 (1): 22- 29.
doi: 10.1016/S0022-3913(13)60005-0
74
EDGAR M W . Saliva its secretion composition and functions[J]. British Dental Journal, 1992, 172 (8): 305- 312.
doi: 10.1038/sj.bdj.4807861
75
SCHIPPER R G , SILLETTI E , VINGERHOEDS M H . Saliva as research material: biochemical, physicochemical and practical aspects[J]. Archives of Oral Biology, 2007, 52 (12): 1114- 1135.
doi: 10.1016/j.archoralbio.2007.06.009
76
ZHENG J , HUANG H , SHI M Y , et al. In vitro study on the wear behaviour of human tooth enamel in citric acid solution[J]. Wear, 2011, 271 (9/10): 2313- 2321.
77
FATHY S M , SWAIN M V . In-vitro wear of natural tooth surface opposed with zirconia reinforced lithium silicate glass ceramic after accelerated ageing[J]. Dental Materials, 2018, 34 (3): 551- 559.
doi: 10.1016/j.dental.2017.12.010
78
ZHANG H , SUN Y , GUO J , et al. The effect of food medium on the wear behaviour of veneering porcelain: an in vitro study using the three-body abrasion mode[J]. Journal of Dentistry, 2019, 83, 87- 94.
doi: 10.1016/j.jdent.2019.02.010
79
PALMER D S , BARCO M T , PELLEU G B . Wear of human enamel against a commercial castable ceramic restorative material[J]. Journal of Prosthetic Dentistry, 1991, 65 (2): 192- 195.
doi: 10.1016/0022-3913(91)90161-O
80
ROOTARE H M , POWERS J M , RAIG R G . Sintered hydroxyapatite ceramic for wear studies[J]. Journal of Dental Research, 1978, 57 (7): 777- 783.
81
ZHENG J , LI Y , SHI M Y , et al. Microtribological behaviour of human tooth enamel and artificial hydroxyapatite[J]. Tribology International, 2013, 63, 177- 185.
doi: 10.1016/j.triboint.2012.04.019
82
PREIS V , BEHR M , HANDEL G , et al. Wear performance of dental ceramics after grinding and polishing treatments[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2012, 10, 13- 22.
doi: 10.1016/j.jmbbm.2012.03.002
83
GILLINGS B . Jaw movements in young adult men during chewing[J]. Journal of Prosthetic Dentistry, 1973, 29 (2): 567- 576.
84
HIIEMAE K , HEATH M R , HEATH G , et al. Natural bites, food consistency and feeding behaviour in man[J]. Archives of Oral Biology, 1996, 41 (2): 175- 189.
doi: 10.1016/0003-9969(95)00112-3
85
WODA A , MISHELLANY A , PEYRON M A . The regulation of masticatory function and food bolus formation[J]. Journal of Oral Rehabilitation, 2006, 33 (11): 840- 849.
doi: 10.1111/j.1365-2842.2006.01626.x
86
KADOKAWA A , SUZUKI S , TANAKA T . Wear evaluation of porcelain opposing gold, composite resin, and enamel[J]. The Journal of Prosthetic Dentistry, 2006, 96 (4): 258- 265.
doi: 10.1016/j.prosdent.2006.08.016
87
DUNNE S . Quantitative measurement of tooth and ceramic wear: in vivo study[J]. International Journal of Prosthodontics, 2008, 21 (3): 245- 252.
88
LAMBRECHTS P , BRAEM M , VUYLSTEKE-WAUTERS M , et al. Quantitative in vivo wear of human enamel[J]. Journal of Dental Research, 1989, 68 (12): 1752- 1754.
doi: 10.1177/00220345890680120601
89
LEI L , ZHENG L , XIAO H , et al. Wear mechanism of human tooth enamel: the role of interfacial protein bonding between HA crystals[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2020, 110, 103845.
doi: 10.1016/j.jmbbm.2020.103845
90
PENG J , XIAO H , YANG D , et al. Surface hardening behavior of enamel by masticatory loading: occurrence mechanism and antiwear effect[J]. ACS Biomaterials Science & Engineering, 2020, 6 (8): 4454- 4461.
91
ZHENG J , ZENG Y , WEN J , et al. Impact wear behavior of human tooth enamel under simulated chewing conditions[J]. Journal of the Mechanical Behavior of Biomedical Materials, 2016, 62, 119- 127.
doi: 10.1016/j.jmbbm.2016.04.039
92
CUI F Z , GE J . New observations of the hierarchical structure of human enamel, from nanoscale to microscale[J]. Journal of Tissue Engineering and Regenerative Medicine, 2007, 1 (3): 185- 191.
doi: 10.1002/term.21
93
WHITE S N , LUO W , PAINE M L , et al. Biological organization of hydroxyapatite crystallites into a fibrous continuum toughens and controls anisotropy in human enamel[J]. Journal of Dental Research, 2001, 80 (1): 321- 326.
doi: 10.1177/00220345010800010501
94
ZHENG J , ZHOU Z R . Study of in vitro wear of human tooth enamel[J]. Tribology Letters, 2007, 26 (2): 181- 189.
doi: 10.1007/s11249-006-9192-7