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Biotribology Recent Progresses and Future Perspectives HOSTED BY Available online at www.sciencedirect.com Biosurface and Biotribology ] (]]]]) ]]]–]]] www.elsevier.com/locate/bsbt Biotribology: Recent progresses and future perspectives Z.R. Zhoua,n, Z.M. Jinb,c aSchool of Mechanical Engineering, Southwest Jiaotong University, Chengdu, China bSchool of Mechanical Engineering, Xian Jiaotong University, Xi'an, China cSchool of Mechanical Engineering, University of Leeds, Leeds, UK Received 6 January 2015; received in revised form 3 March 2015; accepted 3 March 2015 Abstract Biotribology deals with all aspects of tribology concerned with biological systems. It is one of the most exciting and rapidly growing areas of tribology. It is recognised as one of the most important considerations in many biological systems as to the understanding of how our natural systems work as well as how diseases are developed and how medical interventions should be applied. Tribological studies associated with biological systems are reviewed in this paper. A brief history, classification as well as current focuses on biotribology research are analysed according to typical papers from selected journals and presentations from a number of important conferences in this area. Progress in joint tribology, skin tribology and oral tribology as well as other representative biological systems is presented. Some remarks are drawn and prospects are discussed. & 2015 Southwest Jiaotong University. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Keywords: Biotribology; Biosurface; Joint; Skin; Dental Contents 1. Introduction ...................................................................................2 2. Classifications and focuses of current research. ..........................................................3 3. Joint tribology .................................................................................4 3.1. Natural synovial joints ...................................................................... 4 3.2. Artificial replacements....................................................................... 5 3.3. Future developments........................................................................ 6 4. Skin tribology .................................................................................6 4.1. Friction behaviour of human skin ............................................................... 6 4.1.1. Surface properties of human skin ..........................................................7 4.1.2. Skin hydration. ......................................................................7 4.1.3. Physical properties of contacting materials ....................................................7 4.1.4. Sliding velocity and rotational speed . .....................................................8 4.1.5. Ethnicity, gender and age . .............................................................8 4.1.6. Anatomical region ....................................................................8 4.2. Application of skin tribology in the related field..................................................... 8 4.2.1. Skin moisturisers and cosmetics evaluation ...................................................8 nCorresponding author: Tel.: +86 28 87600971; fax: +86 28 87603142. E-mail address: [email protected] (Z.R. Zhou). Peer review under responsibility of Southwest Jiaotong University. http://dx.doi.org/10.1016/j.bsbt.2015.03.001 2405-4518/& 2015 Southwest Jiaotong University. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Please cite this article as: Z.R. Zhou, Z.M. Jin, Biotribology: Recent progresses and future perspectives, Biosurface and Biotribology (2015), http://dx.doi.org/ 10.1016/j.bsbt.2015.03.001 2 Z.R. Zhou, Z.M. Jin / Biosurface and Biotribology ] (]]]]) ]]]–]]] 4.2.2. Skin pathological assessment .............................................................9 4.2.3. Textile material evaluation. ..............................................................9 4.2.4. Mechanism of skin trauma caused by friction..................................................9 4.2.5. Design of the prosthesis interface ..........................................................9 4.2.6. Tactile perception and gripping objects ......................................................9 4.3. Future research questions..................................................................... 9 5. Oral tribology.................................................................................10 5.1. Wear of human teeth .......................................................................10 5.1.1. Composition and structure of human tooth...................................................10 5.1.2. Tooth wear and main factors ............................................................10 5.2. Wear of artificial dental materials ...............................................................12 5.2.1. Metals and alloys....................................................................12 5.2.2. Ceramics . ......................................................................13 5.2.3. Composites . ......................................................................13 5.3. Tribological properties of saliva ................................................................13 5.4. Future developments........................................................................14 6. Tribology of other biological systems.................................................................14 6.1. Cardiovascular system.......................................................................14 6.2. Hair . ..................................................................................15 6.3. Eye . ..................................................................................15 6.4. Animal feet ..............................................................................15 6.5. Animal surfaces . ..........................................................................15 6.6. Plants ..................................................................................16 7. Remarks and outlook. ..........................................................................16 7.1. Safety and long lifetime .....................................................................16 7.2. Engineering bionics ........................................................................16 7.3. Comfort and beauty ........................................................................16 8. Summary. ...................................................................................16 Acknowledgments.................................................................................17 References . ...................................................................................17 1. Introduction one of the most studied and active research areas in the field of tribology. The aim of this paper is to review the current status of The word “biotribology” was firstly used and defined by biotribology research and highlight future directions. Three Dowson in 1970 as “those aspects of tribology concerned with specific examples of biotribology research are considered; joint, biological systems” [1]. However, many investigations and skin and dental, while other areas are briefly discussed. practices were reported on friction, wear and lubrication There are a great number of papers on biotribology in of bio-systems long before the concept of biotribology was various journals. A simple search on Web of Science (searched introduced. on 7 Feb 2015), using topic (TS) as (BIOTRIBOLOn OR Currently, biotribology is one of the most exciting and rapidly BIO-TRIBOLOn) and including all years, shows that the total growing areas of tribology. The range of research activities is counts amounted to 422 and the number of counts has immense and spans many scientific fields. Biotribology has been increased significantly since 1996 (Fig. 1a). Of course it Fig. 1. Number of counts (a) and number of citations (b) in the last 20 years, searched on Web of Science, using topic (TS) as (BIOTRIBOLO* or BIO- TRIBOLO*), on 7 February, 2015. Please cite this article as: Z.R. Zhou, Z.M. Jin, Biotribology: Recent progresses and future perspectives, Biosurface and Biotribology (2015), http://dx.doi.org/ 10.1016/j.bsbt.2015.03.001 Z.R. Zhou, Z.M. Jin / Biosurface and Biotribology ] (]]]]) ]]]–]]] 3 should be pointed out that the actual number of counts should subjects such as joint tribology, skin tribology, oral tribology, be much greater than 422 since there are many other studies tribology of other human bodies or tissues, medical devices, where alternative subject names are used. The number of animal tribology were received from over 20 countries. citations has also steadily increased as shown in Fig. 1b. As more and more investigations are performed in this area, two A number of useful review papers have been written on the journals titled “Biosurface and Biotribology” and “Biotribology” subject, for example [1] and others in the reference list, as well have just been launched recently in response to the requirement for as many special issues as discussed below. establishing an exchange platform for biotribologists. Recently, several special issues on biotribology, oral and dental tribology have been published in tribology journals [2–4]. In addition, about 10 scientific books or edited volumes 2. Classifications
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