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Group I (Co-Cr metal bar with nylon clip) and Group II (PEEK bar with nylon clip). In both groups, two implants were placed in the canine\u2013premolar region using a delayed loading protocol. The primary outcome was Nylon clip wear, it was evaluated using volumetric change and surface roughness assessment at insertion, three months, six months, nine months, and one year. Patient satisfaction was evaluated at six months and one year using a visual analog scale (VAS). Data were collected and statistically analyzed to compare the final outcomes between the two groups.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      The metal group showed significantly higher roughness and volumetric changes with volumetric changes reached 7.49\u00a0\u03bcm\u2009\u00b1\u20090.47 after 12 months (\n                      <jats:italic>P<\/jats:italic>\n                      =.0001) compared to the PEEK group that reached 7.21\u00a0\u03bcm\u2009\u00b1\u20090.43 with no difference was found between them at 12 months (\n                      <jats:italic>P<\/jats:italic>\n                      \u2009=\u2009.188). Patient satisfaction scores were significantly higher in the PEEK group, regarding retention, stability, comfort, and speaking at both 6 months and 1 year (\n                      <jats:italic>P<\/jats:italic>\n                      =.04).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Nylon clips showed clinically acceptable wear performance with both PEEK and metal bars after 1 year, and the PEEK bar demonstrated superior surface properties and patient satisfaction, especially in the first 6 months of the study.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Trial registration<\/jats:title>\n                    <jats:p>The study was approved by the Research Ethics Committee of the faculty of dentistry, Cairo University (No 94\/23) and registered in the Clinical Trials.gov (NCT06909435). Trial Registration date is 27-03-2025.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s12903-026-08020-3","type":"journal-article","created":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T00:34:09Z","timestamp":1774485249000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Nylon clip wear and patient satisfaction in implant-retained mandibular overdenture using PEEK bar versus metal bar: a one-year randomized clinical study"],"prefix":"10.1186","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-5836-5021","authenticated-orcid":false,"given":"Sara Medhat","family":"Mohamed","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7247-4323","authenticated-orcid":false,"given":"Doaa Amr Heshmat","family":"Rostom","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,3,26]]},"reference":[{"key":"8020_CR1","doi-asserted-by":"publisher","first-page":"204","DOI":"10.4047\/jap.2012.4.4.204","volume":"4","author":"JY Lee","year":"2012","unstructured":"Lee JY, Kim HY, Shin SW, Bryant SR. 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