{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T23:34:00Z","timestamp":1773444840052,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,15]],"date-time":"2022-01-15T00:00:00Z","timestamp":1642204800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Applied Sciences"],"abstract":"<jats:p>The human head is sometimes subjected to impact loads that lead to skull fracture or other injuries that require the removal of part of the skull, which is called craniectomy. Consequently, the removed portion is replaced using autologous bone or alloplastic material. The aim of this work is to develop a cranial implant to fulfil a defect created on the skull and then study its mechanical performance by integrating it on a human head finite element model. The material chosen for the implant was PEEK, a thermoplastic polymer that has been recently used in cranioplasty. A6 numerical model head coupled with an implant was subjected to analysis to evaluate two parameters: the number of fixation screws that enhance the performance and ensure the structural integrity of the implant, and the implant\u2019s capacity to protect the brain compared to the integral skull. The main findings point to the fact that, among all tested configurations of screws, the model with eight screws presents better performance when considering the von Mises stress field and the displacement field on the interface between the implant and the skull. Additionally, under the specific analyzed conditions, it is observable that the model with the implant offers more efficient brain protection when compared with the model with the integral skull.<\/jats:p>","DOI":"10.3390\/app12020878","type":"journal-article","created":{"date-parts":[[2022,1,16]],"date-time":"2022-01-16T20:44:00Z","timestamp":1642365840000},"page":"878","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Mechanical Strength Study of a Cranial Implant Using Computational Tools"],"prefix":"10.3390","volume":"12","author":[{"given":"Pedro O.","family":"Santos","sequence":"first","affiliation":[{"name":"Center for Mechanical Technology an Automation, Department of Mechanical Engineering, Campus de Santiago, University of Aveiro, 3810-183 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2007-5988","authenticated-orcid":false,"given":"Gustavo P.","family":"Carmo","sequence":"additional","affiliation":[{"name":"Center for Mechanical Technology an Automation, Department of Mechanical Engineering, Campus de Santiago, University of Aveiro, 3810-183 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5848-6424","authenticated-orcid":false,"given":"Ricardo J. Alves de","family":"Sousa","sequence":"additional","affiliation":[{"name":"Center for Mechanical Technology an Automation, Department of Mechanical Engineering, Campus de Santiago, University of Aveiro, 3810-183 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9751-8807","authenticated-orcid":false,"given":"F\u00e1bio A. O.","family":"Fernandes","sequence":"additional","affiliation":[{"name":"Center for Mechanical Technology an Automation, Department of Mechanical Engineering, Campus de Santiago, University of Aveiro, 3810-183 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8081-8336","authenticated-orcid":false,"given":"Mariusz","family":"Ptak","sequence":"additional","affiliation":[{"name":"Faculty of Mechanical Engineering, Wroclaw University of Science and Technology, Lukasiewicza 7\/9, 50-371 Wroc\u0142aw, Poland"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,15]]},"reference":[{"key":"ref_1","unstructured":"Becker, C. (2021, November 01). Skull: Anatomy, structure, bones, quizzes. Available online: https:\/\/www.kenhub.com\/en\/library\/anatomy\/the-skull."},{"key":"ref_2","unstructured":"Evans, K. (2012). Physiology of cortical and trabecular bone. The Diagnosis and Treatment of Osteoporosis, Van-Griner."},{"key":"ref_3","first-page":"143","article-title":"Investigation of biomechanics of skull structures damages caused by dynamic loads","volume":"20","author":"Ptak","year":"2018","journal-title":"Acta Bioeng. Biomech."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"342","DOI":"10.1016\/j.jmbbm.2017.01.012","article-title":"On the mechanical behaviour of PEEK and HA cranial implants under impact loading","volume":"69","author":"Jayamohan","year":"2017","journal-title":"J. Mech. Behav. Biomed. Mater."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"198","DOI":"10.1016\/j.wneu.2021.01.102","article-title":"Evaluation of Patient-Specific Cranial Implant Design Using Finite Element Analysis","volume":"148","author":"Huys","year":"2021","journal-title":"World Neurosurg."},{"key":"ref_6","first-page":"139","article-title":"The Recent Revolution in the Design and Manufacture of Cranial Implants: Modern Advancements and Future Directions","volume":"176","author":"Bonda","year":"2016","journal-title":"Physiol. Behav."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"102977","DOI":"10.1016\/j.arabjc.2020.102977","article-title":"PEEK (Polyether-ether-ketone) and its composite materials in orthopedic implantation","volume":"14","author":"Ma","year":"2021","journal-title":"Arab. J. Chem."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"143","DOI":"10.1016\/j.brainresbull.2019.08.010","article-title":"The application of polyetheretherketone (PEEK) implants in cranioplasty","volume":"153","author":"Zhang","year":"2019","journal-title":"Brain Res. Bull."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1016\/j.jpor.2015.10.001","article-title":"Applications of polyetheretherketone (PEEK) in oral implantology and prosthodontics","volume":"60","author":"Najeeb","year":"2016","journal-title":"J. Prosthodont. Res."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1016\/j.jare.2020.09.004","article-title":"Polyetherketoneketone (PEKK): An emerging biomaterial for oral implants and dental prostheses","volume":"28","author":"Alqurashi","year":"2021","journal-title":"J. Adv. Res."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Zafar, M.S. (2020). Prosthodontic Applications of Polymethyl Methacrylate (PMMA): An Update. Polymers, 12.","DOI":"10.3390\/polym12102299"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"412","DOI":"10.1016\/j.msec.2018.11.075","article-title":"The potential of the three-dimensional printed titanium mesh implant for cranioplasty surgery applications: Biomechanical behaviors and surface properties","volume":"97","author":"Huang","year":"2018","journal-title":"Mater. Sci. Eng. C"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"127227","DOI":"10.1016\/j.matlet.2019.127227","article-title":"Fabrication and evaluation of 3-D printed PEEK scaffolds containing Macropores by design","volume":"263","author":"Elhattab","year":"2020","journal-title":"Mater. Lett."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"de Santis, R., Russo, T., Rau, J.V., Papallo, I., Martorelli, M., and Gloria, A. (2021). Design of 3d additively manufactured hybrid structures for cranioplasty. Materials, 14.","DOI":"10.3390\/ma14010181"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"655","DOI":"10.1016\/j.jmapro.2021.01.057","article-title":"Design and 3D bioprinting of interconnected porous scaffolds for bone regeneration. An additive manufacturing approach","volume":"64","author":"Roque","year":"2021","journal-title":"J. Manuf. Process."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1266","DOI":"10.1016\/j.jcms.2016.07.005","article-title":"Outcome in patient-specific PEEK cranioplasty: A two-center cohort study of 40 implants","volume":"44","author":"Jonkergouw","year":"2016","journal-title":"J. Cranio-Maxillofac. Surg."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"e814","DOI":"10.1016\/j.wneu.2019.02.157","article-title":"Incidence and Risk Factors for Skull Implant Displacement After Cranial Surgery","volume":"126","author":"Rashidi","year":"2019","journal-title":"World Neurosurg."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"88","DOI":"10.1016\/j.compstruct.2014.12.061","article-title":"Mechanical impact behavior of polyether-ether-ketone (PEEK)","volume":"124","author":"Rusinek","year":"2015","journal-title":"Compos. Struct."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"598","DOI":"10.1016\/j.polymer.2006.11.032","article-title":"The mechanical properties of poly(ether-ether-ketone) (PEEK) with emphasis on the large compressive strain response","volume":"48","author":"Rae","year":"2007","journal-title":"Polymer"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1016\/0013-7944(85)90052-9","article-title":"Fracture characteristics of three metals subjected to various strains, strain rates, temperatures and pressures","volume":"21","author":"Johnson","year":"1985","journal-title":"Eng. Fract. Mech."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Sobieraj, M., and Rimnac, C. (2012). Fracture, Fatigue, and Notch Behavior of PEEK. PEEK Biomaterials Handbook, Elsevier.","DOI":"10.1016\/B978-1-4377-4463-7.10005-3"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"477","DOI":"10.1108\/EC-09-2016-0321","article-title":"Development and validation of a new finite element human head model: Yet another head model (YEAHM)","volume":"35","author":"Fernandes","year":"2018","journal-title":"Eng. Comput."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"104","DOI":"10.1016\/j.clinbiomech.2019.02.010","article-title":"Detection of bridging veins rupture and subdural haematoma onset using a finite element head model","volume":"63","author":"Migueis","year":"2019","journal-title":"Clin. Biomech."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"103976","DOI":"10.1016\/j.jmbbm.2020.103976","article-title":"Prediction of subdural haematoma based on a detailed numerical model of the cerebral bridging veins","volume":"111","author":"Costa","year":"2020","journal-title":"J. Mech. Behav. Biomed. Mater."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Barbosa, A., Fernandes, F.A.O., de Sousa, R.J.A., Ptak, M., and Wilhelm, J. (2020). Computational modeling of skull bone structures and simulation of skull fractures using the YEAHM head model. Biology, 9.","DOI":"10.3390\/biology9090267"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"43","DOI":"10.1016\/j.compbiomed.2019.04.016","article-title":"Biomechanical performance of cranial implants with different thicknesses and material properties: A finite element study","volume":"109","author":"Narra","year":"2019","journal-title":"Comput. Biol. Med."},{"key":"ref_27","unstructured":"Korolija, A. (2012). FE-Modeling of Bolted Joints in Structures, Link\u00f6ping University."},{"key":"ref_28","unstructured":"Huth, H. (1983). Experimenal Determination of Fastener Flexibilities, Aircraft Division Saab-Scania AB."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1227","DOI":"10.1682\/JRRD.2007.06.0092","article-title":"Estimation, simulation, and experimentation of a fall from bed","volume":"45","author":"Schulz","year":"2008","journal-title":"J. Rehabil. Res. Dev."},{"key":"ref_30","unstructured":"Fahlstedt, M., Baeck, K., Halldin, P., Van Der Sloten, J., Goffin, J., Depreitere, B., and Kleiven, S. (2012, January 12\u201314). Influence of impact velocity and angle in a detailed reconstruction of a bicycle accident. Proceedings of the 2012 IRCOBI Conference Proceedings\u2014International Research Council on the Biomechanics of Injury Conference, Dublin, Ireland."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/j.aap.2015.03.012","article-title":"Investigation of the relationship between facial injuries and traumatic brain injuries using a realistic subject-specific finite element head model","volume":"79","author":"Tse","year":"2015","journal-title":"Accid. Anal. 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