{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,30]],"date-time":"2025-11-30T09:18:14Z","timestamp":1764494294352,"version":"build-2065373602"},"reference-count":26,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2023,8,30]],"date-time":"2023-08-30T00:00:00Z","timestamp":1693353600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Polish Ministry of Science and Education","award":["0614\/SBAD\/1565","0614\/SBAD\/1579"],"award-info":[{"award-number":["0614\/SBAD\/1565","0614\/SBAD\/1579"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This study demonstrates a new method for quantifying thread engagement in mechanical connections and verifies its applicability using biomedical implants under push-out tests. The focus is on orthopedic plate implants employed for bone fracture fixation, which, by design, allow off-axis screw insertion to accommodate different contact conditions. Thread engagement is crucial in determining connection strength and stability. In medical practice, off-axis screw placement is usually necessary due to bone geometries and implant plate rigidity. To address this, the study proposes a quantification method using non-destructive testing with X-ray micro-computed tomography and automated image processing, although tuning the image processing parameters is vital for accurate and reliable results. This enables detailed 3D models of screw-plate interfaces for precise thread engagement measurement. The results show that thread engagement decreases with both, increased off-axis insertion angles and higher torque during insertion. Correlation analysis reveals a strong relationship (R2 &gt; 0.6) between average thread engagement and push-out strength, underscoring the importance of proper screw placement for stable fixation.<\/jats:p>","DOI":"10.3390\/ma16175926","type":"journal-article","created":{"date-parts":[[2023,8,30]],"date-time":"2023-08-30T10:30:52Z","timestamp":1693391452000},"page":"5926","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Quantification of Thread Engagement in Screw-Plate Interface of Polyaxial Locking System Using X-ray Computed Tomography"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4715-6358","authenticated-orcid":false,"given":"Tomasz","family":"Bartkowiak","sequence":"first","affiliation":[{"name":"Institute of Mechanical Technology, Poznan University of Technology, 60-965 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daria","family":"Madali\u0144ska","sequence":"additional","affiliation":[{"name":"Institute of Mechanical Technology, Poznan University of Technology, 60-965 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2300-0834","authenticated-orcid":false,"given":"Patryk","family":"Mietli\u0144ski","sequence":"additional","affiliation":[{"name":"Institute of Mechanical Technology, Poznan University of Technology, 60-965 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jakub","family":"Kaczmarek","sequence":"additional","affiliation":[{"name":"VETACARE\u2014Dr. Philipp Winkels, 50374 Erftstadt, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0206-1942","authenticated-orcid":false,"given":"Bartosz","family":"Gapi\u0144ski","sequence":"additional","affiliation":[{"name":"Institute of Mechanical Technology, Poznan University of Technology, 60-965 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5076-8128","authenticated-orcid":false,"given":"Marcin","family":"Pelic","sequence":"additional","affiliation":[{"name":"Institute of Mechanical Technology, Poznan University of Technology, 60-965 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6054-8834","authenticated-orcid":false,"given":"Piotr","family":"Paczos","sequence":"additional","affiliation":[{"name":"Institute of Applied Mechanics, Poznan University of Technology, 60-965 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"857","DOI":"10.1007\/s00264-013-2210-0","article-title":"Mono- versus Polyaxial Locking Plates in Distal Femur Fractures: A Prospective Randomized Multicentre Clinical Trial","volume":"38","author":"Hanschen","year":"2014","journal-title":"Int. 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Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1055\/s-0042-1750431","article-title":"What Is the Cost of Off-Axis Insertion of Locking Screws? A Biomechanical Comparison of a 3.5\u2009Mm Fixed-Angle and 3.5\u2009Mm Variable-Angle Stainless Steel Locking Plate Systems","volume":"35","author":"Kaczmarek","year":"2022","journal-title":"Vet. Comp. Orthop. Traumatol."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Anders, J.L., Cismoski, D.A., Pattillo, P., Fox, A., and Pitts, D. (2008, January 21). Analysis of Thread Engagement Requirements for Studs and Nuts. Proceedings of the SPE Annual Technical Conference and Exhibition, Denver, CO, USA.","DOI":"10.2118\/116765-MS"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Parisen, J.D. (SAE Technical Paper 680130, 1968). 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