title: A glass fiber-reinforced composite - bioactive glass cranioplasty implant: A case study of an early development stage implant removed due to a late infection.
abstract: This case study describes the properties of an early development stage bioactive glass containing fiber-reinforced composite calvarial implant with histology that has been in function for two years and three months. The patient is a 33-year old woman with a history of substance abuse, who sustained a severe traumatic brain injury later unsuccessfully treated with an autologous bone flap and a custom-made porous polyethylene implant. She was thereafter treated with developmental stage glass fiber-reinforced composite - bioactive glass implant. After two years and three months, the implant was removed due to an implant site infection. The implant was analyzed histologically, mechanically, and in terms of chemistry and dissolution of bioactive glass. Mechanical integrity of the load bearing fiber-reinforced composite part of the implant was not affected by the in vivo period. Bioactive glass particles demonstrated surface layers of hydroxyapatite like mineral and dissolution, and related increase of pH was considerably less after two and three months period than that for fresh bioactive glass. There was a difference in the histology of the tissues inside the implant areas near to the margin of the implant that absorbed blood during implant installation surgery, showed fibrous tissue with blood vessels, osteoblasts, collagenous fibers with osteoid formation, and tiny clusters of more mature hard tissue. In the center of the implant, where there was less absorbed blood, only fibrous tissue was observed. This finding is in line with the combined positron emission tomography - computed tomography examination with (18F)-fluoride marker, which demonstrated activity of the mineralizing bone by osteoblasts especially at the area near to the margin of the implant 10 months after implantation. Based on these promising reactions found in the bioactive glass containing fiber-reinforced composite implant that has been implanted for two years and three months, calvarial reconstruction with the presented material appears to be a feasible method.
authors.affiliation: Division of Clinical Neurosciences, Department of Neurosurgery, Turku University Hospital, PO Box 52, 20521 Turku, Finland; Division of Clinical Neurosciences, Department of Rehabilitation and Brain Trauma, Turku University Hospital, PO Box 52, 20521 Turku, Finland; Department of Neurology, University of Turku, Turku 20014, Finland; Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku, Lemminkäisenkatu 2, 20520 Turku, Finland. Electronic address: jussi.posti@utu.fi.
authors.forename: Jussi P
authors.initials: JP
authors.lastname: Posti
authors.affiliation: Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku, Lemminkäisenkatu 2, 20520 Turku, Finland; Department of Otorhinolaryngology - Head and Neck Surgery, Division of Surgery and Cancer Diseases, Turku University Hospital, PO Box 52, 20521 Turku, Finland.
authors.forename: Jaakko M
authors.initials: JM
authors.lastname: Piitulainen
authors.affiliation: Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Piispankatu 9, 20500 Turku, Finland.
authors.forename: Leena
authors.initials: L
authors.lastname: Hupa
authors.affiliation: Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Piispankatu 9, 20500 Turku, Finland.
authors.forename: Susanne
authors.initials: S
authors.lastname: Fagerlund
authors.affiliation: Division of Clinical Neurosciences, Department of Neurosurgery, Turku University Hospital, PO Box 52, 20521 Turku, Finland; Division of Clinical Neurosciences, Department of Rehabilitation and Brain Trauma, Turku University Hospital, PO Box 52, 20521 Turku, Finland.
authors.forename: Janek
authors.initials: J
authors.lastname: Frantzén
authors.affiliation: Department of Biomaterials Science and Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku, Lemminkäisenkatu 2, 20520 Turku, Finland; Department of Otorhinolaryngology - Head and Neck Surgery, Division of Surgery and Cancer Diseases, Turku University Hospital, PO Box 52, 20521 Turku, Finland.
authors.forename: Kalle M J
authors.initials: KMJ
authors.lastname: Aitasalo
authors.affiliation: Division of Clinical Neurosciences, Department of Neurosurgery, Turku University Hospital, PO Box 52, 20521 Turku, Finland.
authors.forename: Ville
authors.initials: V
authors.lastname: Vuorinen
authors.affiliation: Department of Children and Adolescents, Oulu University Hospital, 90029 OYS, Finland, MRC Oulu, and PEDEGO Research Center Oulu University, PO Box 23, Oulu, Finland.
authors.forename: Willy
authors.initials: W
authors.lastname: Serlo
authors.affiliation: Department of Oral Pathology and Radiology, Institute of Dentistry, University of Turku, Turku 20014, Finland; Department of Pathology, Turku University Hospital, PO Box 52, 20521 Turku, Finland.
authors.forename: Stina
authors.initials: S
authors.lastname: Syrjänen
authors.affiliation: Department of Otorhinolaryngology - Head and Neck Surgery, Division of Surgery and Cancer Diseases, Turku University Hospital, PO Box 52, 20521 Turku, Finland; City of Turku Welfare Division, PO Box 670, 20101 Turku, Finland.
authors.forename: Pekka K
authors.initials: PK
authors.lastname: Vallittu
mesh_terms: D000328:Adult; D001672:Biocompatible Materials; D005260:Female; D005898:Glass; D006801:Humans; D055595:Mechanical Phenomena; D019736:Prostheses and Implants / Q000009:adverse effects*; D016459:Prosthesis-Related Infections / Q000209:etiology* / Q000473:pathology; D012886:Skull / Q000601:surgery*; D013499:Surface Properties; D013997:Time Factors
chemical_list: D001672:Biocompatible Materials; C009753:fiberglass
keywords: Bioactive glass; Calvarial reconstruction; Cranioplasty; Decompressive craniectomy; Fiber-reinforced composite; Traumatic brain injury