Switching On and Off Macrophages by a “Bridge‐Burning” Coating Improves Bone‐Implant Integration under Osteoporosis

The aim of the present study was to evaluate the effect of local melatonin application during surgery on bone implant connection (BIC) in rabbit tibiae. Six 0.8- to 1-year-old male New Zealand rabbits were divided into 3 groups: (1) a control group (CG) in which rabbits were not treated with additive materials and only implant integration was executed; (2) a melatonin dose 1 (MLT D-1) group in which rabbits were treated with 1.2 mg of melatonin locally before implant placement into the rabbits' tibiae; and (3) a melatonin dose 2 (MLT D-2) group in which rabbits were treated with 3 mg melatonin locally before implant placement into the rabbits' tibiae. Four weeks after the procedure, the rabbits were euthanized; their tibiae were dissected from muscles and soft tissues, fixed with formaldehyde, and later embedded in methacrylate. Histologic and histomorphometric analyses were then performed under light microscopy. Following this, BIC was detected histomorphometrically, and P < .05 was considered statistically significant. Results showed that the highest BIC percentage was detected in MLT D-2, with a mean value of 39.46% ± 0.78, as compared with a mean value of 33.89% ± 0.92 in group MLT D-1 and 27.42% ± 0.89 in CG. Similarly, the mean BIC percentage of the MLT D-2 group was the highest among the three, with the mean BIC percentage of the MLT D-1 still registering as higher than CG. Within the limitations of this rabbit study, it appears that local melatonin application during implant surgery may improve BIC.

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Enhancing osseointegration by site-specific laser modification of titanium implants: comparative and correlative analyses of different parameters of bone-implant integration

Frontiers in Bioengineering and Biotechnology ◽

10.3389/conf.fbioe.2016.01.00127 ◽

2016 ◽

Vol 4 ◽

Author(s):

Omar Omar ◽

Johansson Martin ◽

Shah Furqan ◽

Simonsson Hanna ◽

Emanuelsson Lena ◽

...

Keyword(s):

Titanium Implants ◽

Site Specific ◽

Bone Implant ◽

Laser Modification ◽

Implant Integration ◽

Modification Of Titanium

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UV-Photofunctionalization of Titanium Promotes Mechanical Anchorage in A Rat Osteoporosis Model

International Journal of Molecular Sciences ◽

10.3390/ijms21041235 ◽

2020 ◽

Vol 21 (4) ◽

pp. 1235 ◽

Cited By ~ 4

Author(s):

Takashi Taniyama ◽

Juri Saruta ◽

Naser Mohammadzadeh Rezaei ◽

Kourosh Nakhaei ◽

Amirreza Ghassemi ◽

...

Keyword(s):

Gene Expression ◽

Contact Angle ◽

Alkaline Phosphatase ◽

Uv Light ◽

Bone Implant ◽

Post Menopausal Osteoporosis ◽

Ovx Rats ◽

Implant Integration ◽

Pre Treatment

Effects of UV-photofunctionalization on bone-to-titanium integration under challenging systemic conditions remain unclear. We examined the behavior and response of osteoblasts from sham-operated and ovariectomized (OVX) rats on titanium surfaces with or without UV light pre-treatment and the strength of bone-implant integration. Osteoblasts from OVX rats showed significantly lower alkaline phosphatase, osteogenic gene expression, and mineralization activities than those from sham rats. Bone density variables in the spine were consistently lower in OVX rats. UV-treated titanium was superhydrophilic and the contact angle of ddH2O was ≤5°. Titanium without UV treatment was hydrophobic with a contact angle of ≥80°. Initial attachment to titanium, proliferation, alkaline phosphatase activity, and gene expression were significantly increased on UV-treated titanium compared to that on control titanium in osteoblasts from sham and OVX rats. Osteoblastic functions compromised by OVX were elevated to levels equivalent to or higher than those of sham-operated osteoblasts following culture on UV-treated titanium. The strength of in vivo bone-implant integration for UV-treated titanium was 80% higher than that of control titanium in OVX rats and even higher than that of control implants in sham-operated rats. Thus, UV-photofunctionalization effectively enhanced bone-implant integration in OVX rats to overcome post-menopausal osteoporosis-like conditions.

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Disproportionate Effect of Sub-Micron Topography on Osteoconductive Capability of Titanium

International Journal of Molecular Sciences ◽

10.3390/ijms20164027 ◽

2019 ◽

Vol 20 (16) ◽

pp. 4027 ◽

Cited By ~ 5

Author(s):

Juri Saruta ◽

Nobuaki Sato ◽

Manabu Ishijima ◽

Takahisa Okubo ◽

Makoto Hirota ◽

...

Keyword(s):

Rough Surface ◽

Cell Attachment ◽

Biological Effects ◽

Calcium Deposition ◽

Male Rat ◽

Bone Implant ◽

Micro Scale ◽

Titanium Surfaces ◽

Implant Integration

Titanium micro-scale topography offers excellent osteoconductivity and bone–implant integration. However, the biological effects of sub-micron topography are unknown. We compared osteoblastic phenotypes and in vivo bone and implant integration abilities between titanium surfaces with micro- (1–5 µm) and sub-micro-scale (0.1–0.5 µm) compartmental structures and machined titanium. The calculated average roughness was 12.5 ± 0.65, 123 ± 6.15, and 24 ± 1.2 nm for machined, micro-rough, and sub-micro-rough surfaces, respectively. In culture studies using bone marrow-derived osteoblasts, the micro-rough surface showed the lowest proliferation and fewest cells attaching during the initial stage. Calcium deposition and expression of osteoblastic genes were highest on the sub-micro-rough surface. The bone–implant integration in the Sprague–Dawley male rat femur model was the strongest on the micro-rough surface. Thus, the biological effects of titanium surfaces are not necessarily proportional to the degree of roughness in osteoblastic cultures or in vivo. Sub-micro-rough titanium ameliorates the disadvantage of micro-rough titanium by restoring cell attachment and proliferation. However, bone integration and the ability to retain cells are compromised due to its lower interfacial mechanical locking. This is the first report on sub-micron topography on a titanium surface promoting osteoblast function with minimal osseointegration.

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