1
|
Keown AJ, Bush MB, Ford C, Lee JJW, Constantino PJ, Lawn BR. Fracture susceptibility of worn teeth. J Mech Behav Biomed Mater 2012; 5:247-56. [DOI: 10.1016/j.jmbbm.2011.08.028] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 08/17/2011] [Accepted: 08/23/2011] [Indexed: 11/26/2022]
|
2
|
Lee JJW, Constantino PJ, Lucas PW, Lawn BR. Fracture in teeth: a diagnostic for inferring bite force and tooth function. Biol Rev Camb Philos Soc 2011; 86:959-74. [PMID: 21507194 DOI: 10.1111/j.1469-185x.2011.00181.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Teeth are brittle and highly susceptible to cracking. We propose that observations of such cracking can be used as a diagnostic tool for predicting bite force and inferring tooth function in living and fossil mammals. Laboratory tests on model tooth structures and extracted human teeth in simulated biting identify the principal fracture modes in enamel. Examination of museum specimens reveals the presence of similar fractures in a wide range of vertebrates, suggesting that cracks extended during ingestion or mastication. The use of 'fracture mechanics' from materials engineering provides elegant relations for quantifying critical bite forces in terms of characteristic tooth size and enamel thickness. The role of enamel microstructure in determining how cracks initiate and propagate within the enamel (and beyond) is discussed. The picture emerges of teeth as damage-tolerant structures, full of internal weaknesses and defects and yet able to contain the expansion of seemingly precarious cracks and fissures within the enamel shell. How the findings impact on dietary pressures forms an undercurrent of the study.
Collapse
Affiliation(s)
- James J-W Lee
- Ceramics Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
| | | | | | | |
Collapse
|
3
|
Fukuzato Y, Matsuura T, Ozaki K, Matsuura M, Sano T, Nakahara Y, Kodama Y, Nakagawa A, Okamura S, Suido H, Torii K, Makino T, Narama I. Morphological study on dental caries induced in WBN/KobSlc rats (Rattus norvegicus) fed a standard laboratory diet. Lab Anim 2009; 43:376-81. [DOI: 10.1258/la.2008.0080064] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In our previous studies, WBN/KobSlc was characterized as a rat strain in which only males began to develop pancreatitis, and then presented with diabetic symptoms. In the course of studying their pancreatic inflammation, we detected molar caries in prediabetic males feeding on a standard diet (CRF-1) widely used for experimental animals. The purpose of this study is to confirm whether the WBN/KobSlc strain is caries-susceptible to the diet reported to be non-cariogenic, and to examine the effect of a prediabetic condition on their dental caries. For a morphological study, 25 male WBN/KobSlc rats aged 3.2–7.8 months and 24 females of the same strain aged 3.3–6.6 months were used, along with 10 males and 10 females of 8.2-month-old F344 rats. Marked dental caries were detected in the mandibular molars of male and female WBN/KobSlc rats regardless of pancreatitis, although no similar changes were observed in any teeth of the F344 strain fed the same diet. Soft X-ray examination revealed that the caries began in the crown and progressed horizontally and vertically, and that a severe radiolucent lesion extensively expanded to the entire crown, corresponding to a macroscopically deleted molar. The caries had gradually developed mainly in the second mandibular molar from more than 3.5 months of age, while none were seen in any rats before that time. The WBN/KobSlc rats were caries-susceptible even to the standard laboratory diet, and pancreatitis was not directly associated with the onset of dental caries in this strain.
Collapse
Affiliation(s)
| | - Tetsuro Matsuura
- Faculty of Pharmaceutical Sciences, Department of Pathology, Setsunan University, Osaka, Japan
| | - Kiyokazu Ozaki
- Faculty of Pharmaceutical Sciences, Department of Pathology, Setsunan University, Osaka, Japan
| | | | - Tomoya Sano
- Faculty of Pharmaceutical Sciences, Department of Pathology, Setsunan University, Osaka, Japan
| | - Yutaka Nakahara
- Pathology Division, Mitsubishi Chemical Safety Institute Ltd, Kumamoto, Japan
| | - Yasushi Kodama
- Faculty of Pharmaceutical Sciences, Laboratory of Molecular and Cellular Pharmacology, Hiroshima International University, Hiroshima, Japan
| | - Akihito Nakagawa
- The First Department of Oral and Maxillofacial Surgery, Osaka Dental University, Osaka, Japan
| | | | | | - Kayo Torii
- Health Care R&D Division, Sunstar Inc, Osaka, Japan
| | | | - Isao Narama
- Faculty of Pharmaceutical Sciences, Department of Pathology, Setsunan University, Osaka, Japan
| |
Collapse
|
4
|
Lucas P, Constantino P, Wood B, Lawn B. Dental enamel as a dietary indicator in mammals. Bioessays 2008; 30:374-85. [DOI: 10.1002/bies.20729] [Citation(s) in RCA: 232] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|