Histol Histopathol

Original Article Open Access

Sequential osseointegration from osseohealing to osseoremodeling - Histomorphological comparison of novel 3D porous and solid Ti-6Al-4V titanium implants

Alice Frosch1, Sebastian Krohn2, Gottfried Buchhorn1, Wolfgang Lehmann1, Karl-Heinz Frosch3, László Füzesi4 and Stephan Frosch1

1Department of Trauma Surgery, Orthopedics and Plastic Surgery, University Medical Center Göttingen, 2Department of Prosthodontics, University Medical Center Göttingen, Göttingen, 3Department of Trauma and Orthopedic Surgery, University Medical Center Hamburg - Eppendorf, Hamburg and 4Department of Pathology, University Medical Center Göttingen, Göttingen, Germany


Corresponding Author: Stephan Frosch, Department of Trauma Surgery, Orthopedics and Plastic Surgery, University Medical Center Göttingen, Robert-Koch-Straße 40, 37075 Göttingen, Germany. e-mail: Stephan.Frosch@med.uni-goettingen.de


Summary. In the present study, we analyzed the histological characteristics of osseointegration of an open-porous Ti-6Al-4V material that was produced in a space holder method creating a 3-D through-pores trabecular design that mimics the inhomogeneity and size relationships of trabecular bone in macro- as well as microstructure. Pairs of cylindrical implants with a porosity of 49% and an average pore diameter of 400 µm (PI) or equal sized solid, corundum blasted devices (SI) as reference were bilaterally implanted press fit in the lateral condyles of 16 rabbits. Histological examination was performed after 4 weeks of short-term osseohealing and 12 weeks of mid-term osseo-remodeling and we summarized the criteria for sequential osseointegration. After 4 weeks, osteoid had already been largely replaced by mineralized woven bone in both types of implants but was only represented to a greater extent in the deeper pores of PI. The cortical as well as trabecular region showed regular osseohealing with excessive and spatially undirected formation of immature woven bone. A dense bone mass was found in the cortical area, while in the trabecular region the bone mass was reduced distinctly, presenting large lacuna-like recesses and a demarcating trabecular structure. The pores near the implant surface contained more mineralized woven bone than the deeper pores. After 12 weeks, the osseoremodeling was largely completed with a physiological maturation to lamellar bone. The newly formed bone mass increased for PI and SI compared to the 4-week group and osteoid was only detectable in the deeper pores. The inhomogeneous trabecular design of the pores enables an excellent ingrowth of mineralized lamellar bone after remodeling to a pore depth of 1800 µm, which proves a functional load transfer from the surrounding bone into the implant. According to the concept of osseointegration by Branemark and Albrektsson, the histological evaluation confirms a successful, superior osseointegration of the presented porous properties improving long-term implant stability. The presented study protocol allows an excellent evaluation and comparison of the sequential osseointegration from short-term osseohealing to mid-term osseoremodeling. Histol Histopathol 36, 753-764 (2021)

Key words: Histology, Porous Titanium Implants, Osseointegration, Osseohealing, Osseoremodeling, Woven Bone, Lamellar Bone, Osteoid

DOI: 10.14670/HH-18-333


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©The Author(s) 2021. Open Access. This article is licensed under a Creative Commons CC-BY International License.