{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:51:10Z","timestamp":1792792270858,"version":"4.5.0"},"reference-count":35,"publisher":"Springer Science and Business Media LLC","issue":"5","license":[{"start":{"date-parts":[[2020,10,16]],"date-time":"2020-10-16T00:00:00Z","timestamp":1602806400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2020,10,16]],"date-time":"2020-10-16T00:00:00Z","timestamp":1602806400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Universit\u00e4tsklinik M\u00fcnchen"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Clin Oral Invest"],"published-print":{"date-parts":[[2021,5]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec>\n                <jats:title>Objectives<\/jats:title>\n                <jats:p>To examine the retention force of removable dental prosthesis (RDP) clasps made from polyetheretherketone (PEEK) and cobalt-chrome-molybdenum (CoCrMo, control group) after storage in water and artificial aging.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Materials and methods<\/jats:title>\n                <jats:p>For each material, 15 Bonwill clasps with retentive buccal and reciprocal lingual arms situated between the second pre- and first molar were manufactured by milling (Dentokeep [PEEKmilled1], NT digital implant technology; breCAM BioHPP Blank [PEEKmilled2], bredent), pressing (BioHPP Granulat for 2 press [PEEKpressed], bredent), or casting (remanium GM 800+ [CoCrMo], Dentaurum); <jats:italic>N<\/jats:italic> = 60, <jats:italic>n<\/jats:italic> = 15\/subgroup. A total of 50 retention force measurements were performed for each specimen per aging level (initial; after storage [30 days, 37 \u00b0C] and 10,000 thermal cycles; after storage [60 days, 37 \u00b0C] and 20,000 thermal cycles) in a pull-off test. Data were statistically analyzed using one-way ANOVA, post hoc Scheff\u00e9 and mixed models (<jats:italic>p<\/jats:italic> &lt; 0.05).<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>Initial, PEEKpressed (80.2 \u00b1 35.2) and PEEKmilled1 (98.9 \u00b1 40.3) presented the lowest results, while PEEKmilled2 (170.2 \u00b1 51.8) showed the highest values. After artificial aging, the highest retention force was observed for the control group (131.4 \u00b1 56.8). The influence of artificial aging was significantly higher for PEEK-based materials. While PEEKmilled2 and PEEKpressed showed an initial decline in retention force, all other groups presented no impact or an increase in retention force over a repetitive insertion and removal of the clasps.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>Within the tested PEEK materials, PEEKmilled2 presented superior results than PEEKpressed. Although CoCrMo showed higher values after artificial aging, all materials exhibited sufficient retention to recommend usage under clinical conditions.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Clinical relevance<\/jats:title>\n                <jats:p>As RDPs are still employed for a wide range of indications, esthetic alternatives to conventional CoCrMo clasps are sought.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1007\/s00784-020-03642-5","type":"journal-article","created":{"date-parts":[[2020,10,16]],"date-time":"2020-10-16T10:03:28Z","timestamp":1602842608000},"page":"3141-3149","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":32,"title":["Retention force of polyetheretherketone and cobalt-chrome-molybdenum removable dental prosthesis clasps after artificial aging"],"prefix":"10.1007","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0089-9995","authenticated-orcid":false,"given":"Felicitas","family":"Mayinger","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Danka","family":"Micovic","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Schleich","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Malgorzata","family":"Roos","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marlis","family":"Eichberger","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bogna","family":"Stawarczyk","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2020,10,16]]},"reference":[{"key":"3642_CR1","doi-asserted-by":"publisher","first-page":"273","DOI":"10.1016\/j.prosdent.2017.01.008","volume":"118","author":"SD Campbell","year":"2017","unstructured":"Campbell SD, Cooper L, Craddock H, Hyde TP, Nattress B, Pavitt SH, Seymour DW (2017) Removable partial dentures: the clinical need for innovation. 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