{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T22:49:46Z","timestamp":1787698186527,"version":"build-2784847793"},"reference-count":22,"publisher":"The Angle Orthodontist (EH Angle Education & Research Foundation)","issue":"3","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2010,5]]},"abstract":"<jats:title>Abstract<\/jats:title>\n        <jats:sec>\n          <jats:title>Objective:<\/jats:title>\n          <jats:p>To investigate whether oral cleansing agents affect the essential work of fracture (EWF) and plastic work of fracture (PWF) for two types of orthodontic thermoplastic retainer materials.<\/jats:p>\n        <\/jats:sec>\n        <jats:sec>\n          <jats:title>Materials and Methods:<\/jats:title>\n          <jats:p>Polyethylene-terephthalate-glycol (PETG; Tru-Tain Splint) and polypropylene\/ethylene-propylene rubber (PP-EPR) blend (Essix-C+) sheets were compared. For each material, six sets of 25 sheets were thermoformed into double-edge-notched-tension specimens; subsets of five specimens were formed with internotch distances (L) equal to 6, 8, 10, 12, or 14 mm, respectively. Sets were stored (160 hours, 25\u00b0C) in air (DRY), distilled water (DW), Original Listerine (LIS), mint Crest ProHealth (CPH), 3% hydrogen peroxide (HP), or Polident solution (POL). Specimens were fractured in tension at 2.54 mm\/min. Areas under load-elongation curves were measured to determine total work of fracture (W<jats:sub>f<\/jats:sub>). Linear regressions (W<jats:sub>f<\/jats:sub> vs L [n \u200a=\u200a 25]) yielded intercepts (EWF) and slopes (PWF). Ninety-five percent confidence intervals were used to evaluate differences in EWF and PWF estimates.<\/jats:p>\n        <\/jats:sec>\n        <jats:sec>\n          <jats:title>Results:<\/jats:title>\n          <jats:p>PP-EPR blends showed higher EWFs after storage in HP vs storage in DW. PP-EPR blend showed higher EWFs after storage in CPH vs PETG. After HP storage, PP-EPR exhibited lower PWFs than with any other storage conditions. PP-EPR exhibited higher PWFs than PETG after storage in DRY, DW, and LIS.<\/jats:p>\n        <\/jats:sec>\n        <jats:sec>\n          <jats:title>Conclusions:<\/jats:title>\n          <jats:p>Compared with DW, none of the cleansers decreased the energy to initiate fracture. With one exception, no cleanser decreased the energy to continue plastic fracture extension. In PP-EPR blend, increased resistance to fracture initiation was observed with CPH and HP, yet, surprisingly, HP decreased resistance to plastic fracture growth.<\/jats:p>\n        <\/jats:sec>","DOI":"10.2319\/042809-232.1","type":"journal-article","created":{"date-parts":[[2010,1,5]],"date-time":"2010-01-05T15:19:40Z","timestamp":1262704780000},"page":"554-561","source":"Crossref","is-referenced-by-count":34,"title":["The Essential Work of Fracture of Thermoplastic Orthodontic Retainer Materials"],"prefix":"10.2319","volume":"80","author":[{"given":"Albert L.","family":"Pascual","sequence":"first","affiliation":[{"name":"Resident, Department of Orthodontics, College of Dentistry, University of Kentucky, Lexington, Ky"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cynthia S.","family":"Beeman","sequence":"additional","affiliation":[{"name":"Professor and Program Director, Department of Orthodontics, College of Dentistry, University of Kentucky, Lexington, Ky"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"E. Preston","family":"Hicks","sequence":"additional","affiliation":[{"name":"Professor, Department of Orthodontics, College of Dentistry, University of Kentucky, Lexington, Ky"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heather M.","family":"Bush","sequence":"additional","affiliation":[{"name":"Professor, Department of Biostatistics, College of Public Health, University of Kentucky, Lexington, Ky"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard J.","family":"Mitchell","sequence":"additional","affiliation":[{"name":"Professor, Biomaterials Science, College of Dentistry, University of Kentucky, Lexington, Ky"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1164","reference":[{"key":"i0003-3219-80-3-554-b01","series-title":"Am J Orthod Dentofacial Orthop","first-page":"294","article-title":"Wear comparison of thermoplastic materials used for orthodontic retainers.","volume":"124","author":"Gardner, G. D.","year":"2003","unstructured":"Gardner, G. D., W. J.Dunn, and L.Taloumis. Wear comparison of thermoplastic materials used for orthodontic retainers.Am J Orthod Dentofacial Orthop2003. 124:294\u2013297."},{"key":"i0003-3219-80-3-554-b02","series-title":"Orthodontic Waves","first-page":"64","article-title":"The mechanical properties of dental thermoplastic materials in a simulated intraoral environment.","volume":"65","author":"Ryokawa, H.","year":"2006","unstructured":"Ryokawa, H., A.Fujishima, and K.Maki. The mechanical properties of dental thermoplastic materials in a simulated intraoral environment.Orthodontic Waves2006. 65:64\u201372."},{"key":"i0003-3219-80-3-554-b03","series-title":"Int J Fracture","first-page":"105","article-title":"On the essential work of ductile fracture in polymers.","volume":"32","author":"Mai YW,","year":"1986","unstructured":"Mai YW, \n          \n          On the essential work of ductile fracture in polymers.\n          Int J Fracture\n          1986. 32:105\u2013125."},{"key":"i0003-3219-80-3-554-b04","series-title":"Eng Fracture Mech","first-page":"1009","article-title":"The standardization of the EWF test.","volume":"74","author":"Williams, J. G.","year":"2007","unstructured":"Williams, J. G. and M.Rink. The standardization of the EWF test.Eng Fracture Mech2007. 74:1009\u20131017."},{"key":"i0003-3219-80-3-554-b05","series-title":"Polymer Eng Sci","first-page":"223","article-title":"Essential work of fracture of polypropylene and polypropylene blends over a wide range of test speeds.","volume":"43","author":"Grein, C. P. C.","year":"2003","unstructured":"Grein, C. P. C., Y.Germain, H. H.Kausch, and P.Beguelin. Essential work of fracture of polypropylene and polypropylene blends over a wide range of test speeds.Polymer Eng Sci2003. 43:223\u2013233."},{"key":"i0003-3219-80-3-554-b06","series-title":"J Macromol Sci-Physics","first-page":"635","article-title":"Toward understanding the morphology-related crack initiation and propagation behavior in polypropylene systems as assessed by the essential work of fracture approach.","volume":"B38","author":"Karger-Kocsis, J.","year":"1999","unstructured":"Karger-Kocsis, J.\n          \n          Toward understanding the morphology-related crack initiation and propagation behavior in polypropylene systems as assessed by the essential work of fracture approach.\n          J Macromol Sci-Physics\n          1999. B38:635\u2013646."},{"key":"i0003-3219-80-3-554-b07","series-title":"Eng Fracture Mech","first-page":"617","article-title":"Essential work of fracture mechanics\u2014towards a thickness independent plane stress toughness.","volume":"69","author":"Pardoen, T. M. Y.","year":"2002","unstructured":"Pardoen, T. M. Y. and F.Delannay. Essential work of fracture mechanics\u2014towards a thickness independent plane stress toughness.Eng Fracture Mech2002. 69:617\u2013631."},{"key":"i0003-3219-80-3-554-b08","series-title":"J Mater Sci","first-page":"1844","article-title":"Application of the essential work of fracture method in ranking the performance in service of high-density polyethylene resins employed in pressure pipes.","volume":"43","author":"Peres, F. M.","year":"2008","unstructured":"Peres, F. M.\n          \n          Application of the essential work of fracture method in ranking the performance in service of high-density polyethylene resins employed in pressure pipes.\n          J Mater Sci\n          2008. 43:1844\u20131850."},{"key":"i0003-3219-80-3-554-b09","series-title":"Polymer Bull","first-page":"119","article-title":"For what kind of polymer is the toughness assessment by the essential work concept straightforward?","volume":"37","author":"Karger-Kocsis, J.","year":"1996","unstructured":"Karger-Kocsis, J.\n          \n          For what kind of polymer is the toughness assessment by the essential work concept straightforward?\n          Polymer Bull\n          1996. 37:119\u2013126."},{"key":"i0003-3219-80-3-554-b10","series-title":"Polymer","first-page":"5691","article-title":"Plane stress fracture toughness of physically aged plasticized PETG as assessed by the essential work of fracture (EWF) method.","volume":"44","author":"Karger-Kocsis, J.","year":"2003","unstructured":"Karger-Kocsis, J., T.Barany, and E. J.Moskala. Plane stress fracture toughness of physically aged plasticized PETG as assessed by the essential work of fracture (EWF) method.Polymer2003. 44:5691\u20135699."},{"key":"i0003-3219-80-3-554-b11","article-title":"Testing Protocol for Essential Work of Fracture. European Structural Integrity Society (ESIS) \u2013 TC4 Task Group, 1993.","author":"Gray, A.","unstructured":"Gray, A.\n          \n          Testing Protocol for Essential Work of Fracture. European Structural Integrity Society (ESIS) \u2013 TC4 Task Group, 1993."},{"key":"i0003-3219-80-3-554-b12","series-title":"Analysis of messy data nonreplicated experiments. 2","author":"Milliken, G. A.","year":"1989","unstructured":"Milliken, G. A. and D. E.Johnson. Analysis of messy data nonreplicated experiments. 2. New YorkNYVan Nostrand Reinhold. 1989."},{"key":"i0003-3219-80-3-554-b13","series-title":"Educ Psychol Meas","first-page":"532","article-title":"A primer on the understanding, use, and calculation of confidence intervals that are based on central and noncentral distributions.","volume":"61","author":"Cumming, G.","year":"2001","unstructured":"Cumming, G. and S.Finch. A primer on the understanding, use, and calculation of confidence intervals that are based on central and noncentral distributions.Educ Psychol Meas2001. 61:532\u2013574."},{"key":"i0003-3219-80-3-554-b14","series-title":"Am Psychol","first-page":"170","article-title":"Inference by eye: confidence intervals and how to read pictures of data.","volume":"60","author":"Cumming, G.","year":"2005","unstructured":"Cumming, G. and S.Finch. Inference by eye: confidence intervals and how to read pictures of data.Am Psychol2005. 60:170\u2013180."},{"key":"i0003-3219-80-3-554-b15","series-title":"Stat Med","first-page":"205","article-title":"Inference by eye: reading the overlap of independent confidence intervals.","volume":"28","author":"Cumming, G.","year":"2009","unstructured":"Cumming, G.\n          \n          Inference by eye: reading the overlap of independent confidence intervals.\n          Stat Med\n          2009. 28:205\u2013220."},{"key":"i0003-3219-80-3-554-b16","series-title":"Polymer Bull","first-page":"119","article-title":"For what kind of polymer is the toughness assessment by the essential work concept straightforward?","volume":"37","author":"Karger-Kocsis, J.","year":"1996","unstructured":"Karger-Kocsis, J.\n          \n          For what kind of polymer is the toughness assessment by the essential work concept straightforward?\n          Polymer Bull\n          1996. 37:119\u2013126."},{"key":"i0003-3219-80-3-554-b17","series-title":"Polymer Eng Sci","first-page":"310","article-title":"Effects of gauge length and strain rate on fracture toughness of polyethylene terephthalate glycol (PETG) film using the Essential Work of Fracture analysis.","volume":"40","author":"Ching, E. C. Y.","year":"2000","unstructured":"Ching, E. C. Y., R. K. Y.Li, and Y. W.Mai. Effects of gauge length and strain rate on fracture toughness of polyethylene terephthalate glycol (PETG) film using the Essential Work of Fracture analysis.Polymer Eng Sci2000. 40:310\u2013319."},{"key":"i0003-3219-80-3-554-b18","series-title":"Polymer Degrad Stability","first-page":"271","article-title":"Effect of hygrothermal aging on the essential work of fracture response of amorphous poly(ethylene terephthalate) sheets.","volume":"82","author":"Barany, T.","year":"2003","unstructured":"Barany, T., J.Karger-Kocsis, and T.Czigany. Effect of hygrothermal aging on the essential work of fracture response of amorphous poly(ethylene terephthalate) sheets.Polymer Degrad Stability2003. 82:271\u2013278."},{"key":"i0003-3219-80-3-554-b19","series-title":"J Plast Film Sheeting","first-page":"140","article-title":"Polypropylene surface characteristics after exposure to hydrogen peroxide and heat processing.","volume":"8","author":"Caudill, V.","year":"1992","unstructured":"Caudill, V.\n          \n          Polypropylene surface characteristics after exposure to hydrogen peroxide and heat processing.\n          J Plast Film Sheeting\n          1992. 8:140\u2013154."},{"key":"i0003-3219-80-3-554-b20","series-title":"Int J Fracture","first-page":"189","article-title":"Statistical procedure for improving the precision of the measurement of the essential work of fracture of thin sheets.","volume":"87","author":"Marchal, Y.","year":"1997","unstructured":"Marchal, Y., J. F.Walhin, and F.Delannay. Statistical procedure for improving the precision of the measurement of the essential work of fracture of thin sheets.Int J Fracture1997. 87:189\u2013199."},{"key":"i0003-3219-80-3-554-b21","series-title":"ESIS Publ","first-page":"187","article-title":"ESIS-TC4: Experience with the Essential Work of Fracture method.","volume":"27","author":"Clutton, E.","year":"2000","unstructured":"Clutton, E.\n          \n          ESIS-TC4: Experience with the Essential Work of Fracture method.\n          ESIS Publ\n          2000. 27:187."},{"key":"i0003-3219-80-3-554-b22","series-title":"Ann Biomed Eng","first-page":"335","article-title":"A novel pressure film approach for determining the force imparted by clear removable thermoplastic appliances.","volume":"36","author":"Barbagallo, L. J.","year":"2008","unstructured":"Barbagallo, L. J., G.Shen, A. S.Jones, M. V.Swain, P.Petocz, and M. A.Darendeliler. A novel pressure film approach for determining the force imparted by clear removable thermoplastic appliances.Ann Biomed Eng2008. 36:335\u2013341."}],"container-title":["The Angle Orthodontist"],"original-title":[],"link":[{"URL":"https:\/\/angle-orthodontist.kglmeridian.com\/view\/journals\/angl\/80\/3\/article-p554.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/angle-orthodontist.kglmeridian.com\/downloadpdf\/journals\/angl\/80\/3\/article-p554.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/angle-orthodontist.kglmeridian.com\/downloadpdf\/journals\/angl\/80\/3\/article-p554.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,5,16]],"date-time":"2025-05-16T00:51:07Z","timestamp":1747356667000},"score":1,"resource":{"primary":{"URL":"https:\/\/angle-orthodontist.kglmeridian.com\/view\/journals\/angl\/80\/3\/article-p554.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2010,5]]},"references-count":22,"journal-issue":{"issue":"3"},"URL":"https:\/\/doi.org\/10.2319\/042809-232.1","relation":{},"ISSN":["0003-3219","1945-7103"],"issn-type":[{"value":"0003-3219","type":"print"},{"value":"1945-7103","type":"electronic"}],"subject":[],"published":{"date-parts":[[2010,5]]}}}