{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T07:03:02Z","timestamp":1779692582079,"version":"3.53.1"},"reference-count":27,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T00:00:00Z","timestamp":1779667200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Surg."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Early osseointegration is critical for long-term implant stability, and in-house 3D\u2013printed porous surfaces may enhance bone integration by promoting cellular migration and tissue formation, provided that porosity is balanced with sufficient mechanical strength. This randomized animal study assessed whether statistically significant differences exist between custom 3D\u2013printed titanium implants with a pore size of 630 \u03bcm and porosity of 73.9% (P1) and implants with a pore size of 690 \u03bcm and porosity of 69.1% (P2) regarding mechanical and histological osseointegration.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Twenty stable, non-weight\u2013 bearing cylindrical implants (6 \u00d7 10 mm), comprising ten P1 and ten P2 implants, were randomly inserted into the medial left femoral condyle of 20 skeletally mature sheep. After 4 weeks, the animals were euthanized, and each specimen was divided into one block for mechanical axial push\u2013out testing and another for histomorphometric evaluation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Statistical analysis using the Mann\u2013Whitney U test demonstrated no significant differences between P1 and P2 in strength (MPa;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u2009.87), energy (J\/m2;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u2009.80), or stiffness (MPa\/mm;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u2009.66). Histomorphometric analysis likewise revealed no significant differences in bone or fibrous tissue fractions between groups, and no foreign body reaction was observed in any specimen.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>Within the limitations of this study, no statistically significant differences were detected between the two porous implant designs with respect to early osseointegration, and future research should investigate their performance in weight\u2013bearing conditions.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fsurg.2026.1818355","type":"journal-article","created":{"date-parts":[[2026,5,25]],"date-time":"2026-05-25T06:06:27Z","timestamp":1779689187000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Early osseointegration of two in-house 3D-printed porous titanium implant designs: an in vivo sheep study"],"prefix":"10.3389","volume":"13","author":[{"given":"Anna B.","family":"Borgognoni","sequence":"first","affiliation":[{"name":"Department of Orthopaedic Oncology, Aarhus University Hospital","place":["Aarhus, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah S.","family":"Freund","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Oncology, Aarhus University Hospital","place":["Aarhus, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J\u00f8rgen","family":"Baas","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Oncology, Aarhus University Hospital","place":["Aarhus, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael M.","family":"Bendtsen","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Oncology, Aarhus University Hospital","place":["Aarhus, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeppe S.","family":"Byskov","sequence":"additional","affiliation":[{"name":"Additive Manufacturing, Danish Technological Institute","place":["Aarhus, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bahram","family":"Ranjkesh","sequence":"additional","affiliation":[{"name":"Department of Dentistry and Oral Health, Aarhus University","place":["Aarhus, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jens R.","family":"Nyengaard","sequence":"additional","affiliation":[{"name":"Core Center for Molecular Morphology, Department of Clinical Medicine, Aarhus University","place":["Aarhus, Denmark"]},{"name":"Department of Pathology, Aarhus University Hospital","place":["Aarhus, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruben","family":"Pauwels","sequence":"additional","affiliation":[{"name":"Department of Dentistry and Oral Health, Aarhus University","place":["Aarhus, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Baad-Hansen","sequence":"additional","affiliation":[{"name":"Department of Orthopaedic Oncology, Aarhus University Hospital","place":["Aarhus, Denmark"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,5,25]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"842","DOI":"10.1177\/0300985815593124","article-title":"Animal models for evaluation of bone implants and devices: comparative bone structure and common model uses","volume":"52","author":"Wancket","year":"2015","journal-title":"Vet Pathol"},{"key":"B2","doi-asserted-by":"publisher","first-page":"2","DOI":"10.1007\/s13191-013-0252-z","article-title":"Osseointegration: an update","volume":"13","author":"Parithimarkalaignan","year":"2013","journal-title":"J Indian Prosthodont Soc"},{"key":"B3","doi-asserted-by":"publisher","first-page":"497","DOI":"10.3109\/17453679308993679","article-title":"Prognosis of total hip replacement in Sweden. 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