DOI: 10.1073/pnas.0902466106. Remarkable resilience of teeth

10.1073/pnas.0902466106

Crossref journal-article

Proceedings of the National Academy of Sciences

Proceedings of the National Academy of Sciences (341)

Abstract

Tooth enamel is inherently weak, with fracture toughness comparable with glass, yet it is remarkably resilient, surviving millions of functional contacts over a lifetime. We propose a microstructural mechanism of damage resistance, based on observations from ex situ loading of human and sea otter molars (teeth with strikingly similar structural features). Section views of the enamel implicate tufts, hypomineralized crack-like defects at the enamel–dentin junction, as primary fracture sources. We report a stabilization in the evolution of these defects, by “stress shielding” from neighbors, by inhibition of ensuing crack extension from prism interweaving (decussation), and by self-healing. These factors, coupled with the capacity of the tooth configuration to limit the generation of tensile stresses in largely compressive biting, explain how teeth may absorb considerable damage over time without catastrophic failure, an outcome with strong implications concerning the adaptation of animal species to diet.

Bibliography

Chai, H., Lee, J. J.-W., Constantino, P. J., Lucas, P. W., & Lawn, B. R. (2009). Remarkable resilience of teeth. Proceedings of the National Academy of Sciences, 106(18), 7289â7293.

Authors 5

Herzl Chai (first)
James J.-W. Lee (additional)
Paul J. Constantino (additional)
Peter W. Lucas (additional)
Brian R. Lawn (additional)

References 44 Referenced 212

10.1002/ajpa.1330940306
S Braun, et al., A study of bite force. 1. Relationship to various physical characteristics. Angle Orthodontist 65, 367–372 (1995). / Angle Orthodontist / A study of bite force. 1. Relationship to various physical characteristics by Braun S (1995)
10.1038/35016535
10.1557/JMR.2001.0339
10.1177/00220345760550010901
10.1177/00220345980770030601
10.1002/(SICI)1520-6505(1999)8:4<133::AID-EVAN4>3.0.CO;2-F
10.1002/bies.20729
10.1177/00220345500290030201
10.2307/2798801
10.2307/2388025
10.1002/ajpa.1330730306
10.1017/CBO9780511735011
10.2307/1374968
10.2307/1374939
10.1098/rstb.1981.0013
10.1016/j.jmbbm.2008.05.007
JW Osborn, Dental tissues. Dental Anatomy and Embryology, ed JW Osborn (Blackwell, Oxford) Vol 1, 155–209 (1981). / Dental Anatomy and Embryology by Osborn JW (1981)
10.1038/328150a0
10.1177/00220345490280060401
10.1159/000143313
10.1177/0022034508330055
10.1111/j.1469-185X.1988.tb00630.x
10.1038/nmat1323
10.1016/j.archoralbio.2004.01.016
10.1177/00220345530320021301
10.1111/j.1151-2916.1988.tb05824.x
10.1557/JMR.2005.0343
H Tada, P Paris, GR Irwin The Stress Analysis of Cracks Handbook (Del Research, St Louis), pp. 15.1 (1985). / The Stress Analysis of Cracks Handbook by Tada H (1985)
T Fett, D Munz Stress Intensity Factors and Weight Functions (Computational Mechanics, Southampton, UK), pp. 267–268 (1997). / Stress Intensity Factors and Weight Functions by Fett T (1997)
10.1002/jbm.b.30511
10.1177/08959374890030022601
10.1016/0020-7683(89)90021-8
10.1016/j.biomaterials.2008.08.019
10.1016/0956-7151(93)90316-K
10.1002/jbm.b.30666
10.1038/314260a0
10.1073/pnas.260368897
10.1073/pnas.0711513105
10.1016/S0003-9969(02)00006-7
10.1080/02724634.1999.10011166
10.1126/science.1164865
10.1038/35057232
BR Lawn Fracture of Brittle Solids (Cambridge Univ Press, Cambridge, UK), pp. 16–50 (1993). (10.1017/CBO9780511623127.004) / Fracture of Brittle Solids by Lawn BR (1993)

Dates

Type	When
Created	16 years, 4 months ago (April 13, 2009, 8:45 p.m.)
Deposited	3 years, 4 months ago (April 12, 2022, 5:16 p.m.)
Indexed	54 minutes ago (Aug. 30, 2025, 3:54 a.m.)
Issued	16 years, 3 months ago (May 5, 2009)
Published	16 years, 3 months ago (May 5, 2009)
Published Online	16 years, 3 months ago (May 5, 2009)
Published Print	16 years, 3 months ago (May 5, 2009)

Funders 0

None

BibTeX

@article{Chai_2009, title={Remarkable resilience of teeth}, volume={106}, ISSN={1091-6490}, url={http://dx.doi.org/10.1073/pnas.0902466106}, DOI={10.1073/pnas.0902466106}, number={18}, journal={Proceedings of the National Academy of Sciences}, publisher={Proceedings of the National Academy of Sciences}, author={Chai, Herzl and Lee, James J.-W. and Constantino, Paul J. and Lucas, Peter W. and Lawn, Brian R.}, year={2009}, month=may, pages={7289–7293} }

JSON

{
  "indexed": {
    "date-parts": [
      [
        2025,
        8,
        30
      ]
    ],
    "date-time": "2025-08-30T07:54:24Z",
    "timestamp": 1756540464520
  },
  "reference-count": 44,
  "publisher": "Proceedings of the National Academy of Sciences",
  "issue": "18",
  "content-domain": {
    "domain": [
      "www.pnas.org"
    ],
    "crossmark-restriction": true
  },
  "published-print": {
    "date-parts": [
      [
        2009,
        5,
        5
      ]
    ]
  },
  "abstract": "<jats:p>Tooth enamel is inherently weak, with fracture toughness comparable with glass, yet it is remarkably resilient, surviving millions of functional contacts over a lifetime. We propose a microstructural mechanism of damage resistance, based on observations from ex situ loading of human and sea otter molars (teeth with strikingly similar structural features). Section views of the enamel implicate tufts, hypomineralized crack-like defects at the enamel\u2013dentin junction, as primary fracture sources. We report a stabilization in the evolution of these defects, by \u201cstress shielding\u201d from neighbors, by inhibition of ensuing crack extension from prism interweaving (decussation), and by self-healing. These factors, coupled with the capacity of the tooth configuration to limit the generation of tensile stresses in largely compressive biting, explain how teeth may absorb considerable damage over time without catastrophic failure, an outcome with strong implications concerning the adaptation of animal species to diet.</jats:p>",
  "DOI": "10.1073/pnas.0902466106",
  "type": "journal-article",
  "created": {
    "date-parts": [
      [
        2009,
        4,
        14
      ]
    ],
    "date-time": "2009-04-14T00:45:48Z",
    "timestamp": 1239669948000
  },
  "page": "7289-7293",
  "update-policy": "http://dx.doi.org/10.1073/pnas.cm10313",
  "source": "Crossref",
  "is-referenced-by-count": 212,
  "title": "Remarkable resilience of teeth",
  "prefix": "10.1073",
  "volume": "106",
  "author": [
    {
      "given": "Herzl",
      "family": "Chai",
      "sequence": "first",
      "affiliation": [
        {
          "name": "School of Mechanical Engineering, Tel Aviv University, Tel Aviv 69978, Israel;"
        }
      ]
    },
    {
      "given": "James J.-W.",
      "family": "Lee",
      "sequence": "additional",
      "affiliation": [
        {
          "name": "Department of Anthropology, George Washington University, Washington, DC 20052; and"
        },
        {
          "name": "Ceramics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8520"
        }
      ]
    },
    {
      "given": "Paul J.",
      "family": "Constantino",
      "sequence": "additional",
      "affiliation": [
        {
          "name": "Department of Anthropology, George Washington University, Washington, DC 20052; and"
        }
      ]
    },
    {
      "given": "Peter W.",
      "family": "Lucas",
      "sequence": "additional",
      "affiliation": [
        {
          "name": "Department of Anthropology, George Washington University, Washington, DC 20052; and"
        }
      ]
    },
    {
      "given": "Brian R.",
      "family": "Lawn",
      "sequence": "additional",
      "affiliation": [
        {
          "name": "Ceramics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8520"
        }
      ]
    }
  ],
  "member": "341",
  "published-online": {
    "date-parts": [
      [
        2009,
        5,
        5
      ]
    ]
  },
  "reference": [
    {
      "key": "e_1_3_3_1_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1002/ajpa.1330940306"
    },
    {
      "key": "e_1_3_3_2_2",
      "first-page": "367",
      "article-title": "A study of bite force. 1. Relationship to various physical characteristics",
      "volume": "65",
      "author": "Braun S",
      "year": "1995",
      "unstructured": "S Braun, et al., A study of bite force. 1. Relationship to various physical characteristics. Angle Orthodontist 65, 367\u2013372 (1995).",
      "journal-title": "Angle Orthodontist"
    },
    {
      "key": "e_1_3_3_3_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1038/35016535"
    },
    {
      "key": "e_1_3_3_4_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1557/JMR.2001.0339"
    },
    {
      "key": "e_1_3_3_5_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1177/00220345760550010901"
    },
    {
      "key": "e_1_3_3_6_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1177/00220345980770030601"
    },
    {
      "key": "e_1_3_3_7_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1002/(SICI)1520-6505(1999)8:4<133::AID-EVAN4>3.0.CO;2-F"
    },
    {
      "key": "e_1_3_3_8_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1002/bies.20729"
    },
    {
      "key": "e_1_3_3_9_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1177/00220345500290030201"
    },
    {
      "key": "e_1_3_3_10_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.2307/2798801"
    },
    {
      "key": "e_1_3_3_11_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.2307/2388025"
    },
    {
      "key": "e_1_3_3_12_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1002/ajpa.1330730306"
    },
    {
      "key": "e_1_3_3_13_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1017/CBO9780511735011"
    },
    {
      "key": "e_1_3_3_14_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.2307/1374968"
    },
    {
      "key": "e_1_3_3_15_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.2307/1374939"
    },
    {
      "key": "e_1_3_3_16_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1098/rstb.1981.0013"
    },
    {
      "key": "e_1_3_3_17_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/j.jmbbm.2008.05.007"
    },
    {
      "key": "e_1_3_3_18_2",
      "first-page": "155",
      "volume-title": "Dental Anatomy and Embryology",
      "author": "Osborn JW",
      "year": "1981",
      "unstructured": "JW Osborn, Dental tissues. Dental Anatomy and Embryology, ed JW Osborn (Blackwell, Oxford) Vol 1, 155\u2013209 (1981)."
    },
    {
      "key": "e_1_3_3_19_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1038/328150a0"
    },
    {
      "key": "e_1_3_3_20_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1177/00220345490280060401"
    },
    {
      "key": "e_1_3_3_21_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1159/000143313"
    },
    {
      "key": "e_1_3_3_22_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1177/0022034508330055"
    },
    {
      "key": "e_1_3_3_23_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1111/j.1469-185X.1988.tb00630.x"
    },
    {
      "key": "e_1_3_3_24_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1038/nmat1323"
    },
    {
      "key": "e_1_3_3_25_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/j.archoralbio.2004.01.016"
    },
    {
      "key": "e_1_3_3_26_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1177/00220345530320021301"
    },
    {
      "key": "e_1_3_3_27_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1111/j.1151-2916.1988.tb05824.x"
    },
    {
      "key": "e_1_3_3_28_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1557/JMR.2005.0343"
    },
    {
      "key": "e_1_3_3_29_2",
      "first-page": "15.1",
      "volume-title": "The Stress Analysis of Cracks Handbook",
      "author": "Tada H",
      "year": "1985",
      "unstructured": "H Tada, P Paris, GR Irwin The Stress Analysis of Cracks Handbook (Del Research, St Louis), pp. 15.1 (1985)."
    },
    {
      "key": "e_1_3_3_30_2",
      "first-page": "267",
      "volume-title": "Stress Intensity Factors and Weight Functions",
      "author": "Fett T",
      "year": "1997",
      "unstructured": "T Fett, D Munz Stress Intensity Factors and Weight Functions (Computational Mechanics, Southampton, UK), pp. 267\u2013268 (1997)."
    },
    {
      "key": "e_1_3_3_31_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1002/jbm.b.30511"
    },
    {
      "key": "e_1_3_3_32_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1177/08959374890030022601"
    },
    {
      "key": "e_1_3_3_33_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0020-7683(89)90021-8"
    },
    {
      "key": "e_1_3_3_34_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/j.biomaterials.2008.08.019"
    },
    {
      "key": "e_1_3_3_35_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/0956-7151(93)90316-K"
    },
    {
      "key": "e_1_3_3_36_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1002/jbm.b.30666"
    },
    {
      "key": "e_1_3_3_37_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1038/314260a0"
    },
    {
      "key": "e_1_3_3_38_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1073/pnas.260368897"
    },
    {
      "key": "e_1_3_3_39_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1073/pnas.0711513105"
    },
    {
      "key": "e_1_3_3_40_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1016/S0003-9969(02)00006-7"
    },
    {
      "key": "e_1_3_3_41_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1080/02724634.1999.10011166"
    },
    {
      "key": "e_1_3_3_42_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1126/science.1164865"
    },
    {
      "key": "e_1_3_3_43_2",
      "doi-asserted-by": "publisher",
      "DOI": "10.1038/35057232"
    },
    {
      "key": "e_1_3_3_44_2",
      "doi-asserted-by": "crossref",
      "first-page": "16",
      "DOI": "10.1017/CBO9780511623127.004",
      "volume-title": "Fracture of Brittle Solids",
      "author": "Lawn BR",
      "year": "1993",
      "unstructured": "BR Lawn Fracture of Brittle Solids (Cambridge Univ Press, Cambridge, UK), pp. 16\u201350 (1993)."
    }
  ],
  "container-title": "Proceedings of the National Academy of Sciences",
  "original-title": [],
  "language": "en",
  "link": [
    {
      "URL": "https://pnas.org/doi/pdf/10.1073/pnas.0902466106",
      "content-type": "unspecified",
      "content-version": "vor",
      "intended-application": "similarity-checking"
    }
  ],
  "deposited": {
    "date-parts": [
      [
        2022,
        4,
        12
      ]
    ],
    "date-time": "2022-04-12T21:16:07Z",
    "timestamp": 1649798167000
  },
  "score": 1,
  "resource": {
    "primary": {
      "URL": "https://pnas.org/doi/full/10.1073/pnas.0902466106"
    }
  },
  "subtitle": [],
  "short-title": [],
  "issued": {
    "date-parts": [
      [
        2009,
        5,
        5
      ]
    ]
  },
  "references-count": 44,
  "journal-issue": {
    "issue": "18",
    "published-print": {
      "date-parts": [
        [
          2009,
          5,
          5
        ]
      ]
    }
  },
  "alternative-id": [
    "10.1073/pnas.0902466106"
  ],
  "URL": "http://dx.doi.org/10.1073/pnas.0902466106",
  "relation": {},
  "ISSN": [
    "0027-8424",
    "1091-6490"
  ],
  "subject": [],
  "container-title-short": "Proc. Natl. Acad. Sci. U.S.A.",
  "published": {
    "date-parts": [
      [
        2009,
        5,
        5
      ]
    ]
  },
  "assertion": [
    {
      "value": "2008-11-20",
      "order": 0,
      "name": "received",
      "label": "Received",
      "group": {
        "name": "publication_history",
        "label": "Publication History"
      }
    },
    {
      "value": "2009-05-05",
      "order": 2,
      "name": "published",
      "label": "Published",
      "group": {
        "name": "publication_history",
        "label": "Publication History"
      }
    }
  ]
}