Nano/Micro Hierarchical Bioceramic Coatings for Bone Implant Surface Treatments

Bone implants with surface modifications that promote the physiological activities of osteoblasts are the first step for osseointegration in bone repair. Hydroxyapatite is the main inorganic component in mammal bones and teeth, and nanoscaled hydroxyapatite promotes the adhesion of osteoblastic cells. In this study, we created a nano/micro hierarchical structure using micro-arc oxidation coatings and hydrothermal treatments at 150 °C, 175 °C, and 200 °C for 2, 6, 12, and 24 h. After undergoing hydrothermal treatment for 24 h, CaTiO3 began forming regular-shaped crystals at the surface at 175 °C. In order to decrease the CaTiO3 formations and increase the apatite fabrication, a shorter time of hydrothermal treatment was required at 175 °C. There was still surface damage on samples treated for 6 h at 175 °C; however, the nano/micro hierarchical structures were formed in 2 h at 175 °C. The normalized alkaline phosphatase (ALP) activities of the MC3T3-E1 cells with micro-arc oxidation (MAO) coatings and nano/micro hierarchical bioceramics coatings were 4.51 ± 0.26 and 7.36 ± 0.51 μmol p-NP/mg protein (*** P value of <0.001), respectively. The MC3T3-E1 cells with coatings showed highly statistically significant results in terms of the ALP activity. This proposed nano/micro hierarchical structure promoted cell proliferation and osteogenic differentiation of the osteoblast MC3T3-E1 cells. This study realized a promising nano system for osseointegration via bone implant surface treatments, which can promote the physiological activities of osteoblasts.

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Assessment of the Tissue Response to Modification of the Surface of Dental Implants with Carboxyethylphosphonic Acid and Basic Fibroblastic Growth Factor Immobilization (Fgf-2): An Experimental Study on Minipigs

Biology ◽

10.3390/biology10050358 ◽

2021 ◽

Vol 10 (5) ◽

pp. 358

Author(s):

Javier Aragoneses ◽

Ana Suárez ◽

Nansi López-Valverde ◽

Francisco Martínez-Martínez ◽

Juan Manuel Aragoneses

Keyword(s):

Surface Treatment ◽

Test Group ◽

Mean Value ◽

Control Group ◽

P Value ◽

Implant Surface ◽

Bone Contact ◽

Bone Implant ◽

Significant Difference ◽

The Mean

The aim of this study was to evaluate the effect of implant surface treatment with carboxyethylphosphonic acid and fibroblast growth factor 2 on the bone–implant interface during the osseointegration period in vivo using an animal model. The present research was carried out in six minipigs, in whose left tibia implants were inserted as follows: eight implants with a standard surface treatment, for the control group, and eight implants with a surface treatment of carboxyethylphosphonic acid and immobilization of FGF-2, for the test group. At 4 weeks after the insertion of the implants, the animals were sacrificed for the histomorphometric analysis of the samples. The means of the results for the implant–bone contact variable (BIC) were 46.39 ± 17.49% for the test group and 34.00 ± 9.92% for the control group; the difference was not statistically significant. For the corrected implant–bone contact variable (BICc), the mean value of the test group was 60.48 ± 18.11%, and that for the control group, 43.08 ± 10.77%; the difference was statistically significant (p-value = 0.035). The new bone formation (BV/TV) showed average results of 27.28 ± 3.88% for the test group and 26.63 ± 7.90% for the control group, meaning that the differences were not statistically significant (p-value = 0.839). Regarding the bone density at the interthread level (BAI/TA), the mean value of the test group was 32.27 ± 6.70%, and that of the control group was 32.91 ± 7.76%, with a p-value of 0.863, while for the peri-implant density (BAP/TA), the mean value of the test group was 44.96 ± 7.55%, and that for the control group was 44.80 ± 8.68%, without a significant difference between the groups. The current research only found a significant difference for the bone–implant contact at the cortical level; therefore, it could be considered that FGF-2 acts on the mineralization of bone tissue. The application of carboxyethylphosphonic acid on the surface of implants can be considered a promising alternative as a biomimetic coating for the immobilization of FGF-2. Despite no differences in the new bone formation around the implants or in the interthread or peri-implant bone density being detected, the biofunctionalization of the implant surface with FGF-2 accelerates the mineralization of the bone–implant interface at the cortical level, thereby reducing the osseointegration period.

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Histometric Analysis of Bone Repair in Bone-Implant Interface Using a Polylactic/Polyglycolic Acid Copolymer Associated With Implants in Rabbit Tibia

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-10-00102 ◽

2012 ◽

Vol 38 (S1) ◽

pp. 449-457 ◽

Cited By ~ 5

Author(s):

Alexandre Rodrigues Freire ◽

Ana Cláudia Rossi ◽

Thallita Pereira Queiroz ◽

Jéssica Lemos Gulinelli ◽

Francisley Ávila Souza ◽

...

Keyword(s):

Bone Repair ◽

Primary Stability ◽

Polyglycolic Acid ◽

Titanium Implants ◽

New Bone Formation ◽

Implant Surface ◽

Alizarin Red ◽

Bone Implant ◽

Acid Copolymer ◽

Rabbit Tibia

The purpose of this study was to evaluate the association of the combination of polylactic/polyglycolic acid around implants installed with and without primary stability through the histometric analysis of bone-implant interface. We used male rabbits, each of which received 2 titanium implants in each tibial metaphysis. The animals were divided into 4 groups: control with primary stability (CPS), control without primary stability (C), polymer with primary stability (PPS), and polymer without primary stability (P). Euthanasia was performed at postoperative days 40 and 90. The pieces were embedded in resin, sectioned, scraped, and stained with alizarin red and Stevenel blue. Histometric analysis evaluated the linear extension of contact between the bone and implant surface on the implant collar (CIC) and contact between the bone and implant surface on the first thread (CFT). Also evaluated was the area of newly formed bone (ANB) in the first thread. The results showed that there was new bone formation in all groups and during all periods. At 40 days, the ANB was higher in the PPS group than in the P group (P < .001); the CFT was statistically higher in the CPS group than the PPS group (P < .001) and was higher in the CPS group than the C group (P < .001). At 40 and 90 days, the CIC was higher in the P group than in the C group (P < .001). In conclusion, the copolymer had biocompatibility, enhanced bone healing, and presented osteoconductive properties, thus raising the contact between bone and implant, even without primary stability.

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Heat Generated During Seating of Dental Implant Fixtures

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-13-00261 ◽

2014 ◽

Vol 40 (2) ◽

pp. 174-181 ◽

Cited By ~ 9

Author(s):

Dennis Flanagan

Keyword(s):

Dental Implant ◽

Large Diameter ◽

In Vitro Study ◽

Frictional Heat ◽

P Value ◽

Implant Surface ◽

Bone Implant ◽

Average Temperature ◽

Clinically Significant

Frictional heat can be generated during seating of dental implants into a drill-prepared osteotomy. This in vitro study tested the heat generated by implant seating in dense bovine mandible ramus. A thermocouple was placed approximately 0.5 mm from the rim of the osteotomy during seating of each dental implant. Four diameters of implants were tested. The average temperature increases were 0.075°C for the 5.7-mm-diameter implant, 0.97°C for the 4.7-mm-diameter implant, 1.4°C for the 3.7-mm-diameter implant, and 8.6°C for the 2.5-mm-diameter implant. The results showed that heat was indeed generated and a small temperature rise occurred, apparently by the friction of the implant surface against the fresh-cut bone surface. Bone is a poor thermal conductor. The titanium of the implant and the steel of the handpiece are much better heat conductors. Titanium may be 70 times more heat conductive than bone. The larger diameter and displacement implant may act as a heat sink to draw away any heat produced from the friction of seating the implant at the bone-implant interface. The peak temperature duration was momentary, and not measured, but this was approximately less than 1 second. Except for the 2.5-mm-diameter implants, the temperature rises and durations were found to be below those previously deemed to be detrimental, so no clinically significant osseous damage would be expected during dental implant fixture seating of standard and large-diameter-sized implants. A 2.5-mm implant may generate detrimental heat during seating in nonvital bone, but this may be clinically insignificant in vital bone. The surface area and thermal conductivity are important factors in removing generated heat transfer at the bone-implant interface. The F value as determined by analysis of variance was 69.22, and the P value was less than .0001, demonstrating significant differences between the groups considered as a whole.

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Titanium Implants Coated with a Bifunctional Molecule with Antimicrobic Activity: A Rabbit Study

Materials ◽

10.3390/ma13163613 ◽

2020 ◽

Vol 13 (16) ◽

pp. 3613 ◽

Cited By ~ 2

Author(s):

Antonio Scarano ◽

Francesco Carinci ◽

Tiziana Orsini ◽

Luca Valbonetti ◽

Erda Qorri ◽

...

Keyword(s):

Titanium Dioxide ◽

Titanium Dioxide Nanoparticles ◽

Titanium Implants ◽

P Value ◽

Implant Surface ◽

Bone Implant ◽

Bifunctional Molecule ◽

Significant Difference ◽

Bone Implant Contact ◽

Antimicrobic Activity

Background: Various surface treatments have been tested for titanium implants aiming at increasing their surface biocompatibility and their biological characteristics, but also the efficiency of the implant surface will have to be improved to drastically decrease peri-implantite and mucosite. In fact, the peri-implantitis and peri-implant mucositis have a high incidence in clinical practice. The nanofabrication techniques that offer the possibility to achieve the implant surface that reduces bacterial colonization could influence the osteointegration. The aim of this research was to evaluate the bone response to titanium implants coated with a bifunctional molecule with antimicrobic activity consisting of a combination of silver ions covalently bound to titanium dioxide nanoparticles. Methods: A total of 36 implants were inserted into 18 older New Zealand white male rabbits. They had two different surfaces. The implants Control group was characterized by an acid-etched and sandblasted surface treatment, and the Test implants had an acid-etched and sandblasted surface coated with a silver ion covalently bound to titanium dioxide nanoparticles in the solution. Results: No statistically significant difference of the bone density was evidenced between Control and Test implants at two weeks (p-value = 0.623), four weeks (p-value = 0.339), and eight weeks (p-value = 0.461). Moreover, no statistically significant difference of the bone-implant contact percentage was evidenced between Control and Test implants at two weeks (p-value = 0.938), four weeks (p-value = 0.307), and eight weeks (p-value = 0.294). The effectiveness of the present investigation demonstrated no adverse effects on osseointegration, and no statistically significant differences were observed in the bone density and percentage of bone-implant contact between Test and Control implants at all the experimental time points (two, four, and eight weeks). Conclusions: Titanium implants coated with the silver-anatase solution bind very well to the bone and did not have an adverse effect on the bone tissue in a rabbit model. These facts suggest possible clinical applications for the silver composition.

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Histomorphometric Analysis of the Bone-Implant Contact Obtained with 4 Different Implant Surface Treatments Placed Side By Side in the Dog Mandible

Implant Dentistry ◽

10.1097/00008505-200211040-00051 ◽

2002 ◽

Vol 11 (4) ◽

pp. 394 ◽

Cited By ~ 3

Author(s):

Thomas W. Oates

Keyword(s):

Surface Treatments ◽

Histomorphometric Analysis ◽

Implant Surface ◽

Bone Implant ◽

Bone Implant Contact

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Relationships between hierarchical structure and properties in macromolecular systems

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126950 ◽

1987 ◽

Vol 45 ◽

pp. 440-443

Author(s):

E. Baer

Keyword(s):

Uniaxial Tension ◽

Hierarchical Structure ◽

Inorganic Material ◽

Hierarchical Structures ◽

Bone Collagen ◽

Structure And Properties ◽

Connective Tissues ◽

Scale Level ◽

Fibrous Protein ◽

Macromolecular Systems

The most advanced macromolecular materials are found in plants and animals, and certainly the connective tissues in mammals are amongst the most advanced macromolecular composites known to mankind. The efficient use of collagen, a fibrous protein, in the design of both soft and hard connective tissues is worthy of comment. Very crudely, in bone collagen serves as a highly efficient binder for the inorganic hydroxyappatite which stiffens the structure. The interactions between the organic fiber of collagen and the inorganic material seem to occur at the nano (scale) level of organization. Epitatic crystallization of the inorganic phase on the fibers has been reported to give a highly anisotropic, stress responsive, structure. Soft connective tissues also have sophisticated oriented hierarchical structures. The collagen fibers are “glued” together by a highly hydrated gel-like proteoglycan matrix. One of the simplest structures of this type is tendon which functions primarily in uniaxial tension as a reinforced elastomeric cable between muscle and bone.

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Hierarchical composition in complex object drawing

10.31234/osf.io/zgpq9 ◽

2019 ◽

Author(s):

Michiru Makuuchi

Keyword(s):

Hierarchical Structure ◽

Homo Sapiens ◽

Hierarchical Structures ◽

Target Object ◽

Point Of View ◽

Complex Object ◽

Complex Objects ◽

Cognitive Domains ◽

Adult Participants ◽

Symbolic Cognition

Symbolic behaviours such as language, music, drawing, dance, etc. are unique to humans and are found universally in every culture on earth1. These behaviours operate in different cognitive domains, but they are commonly characterised as linear sequences of symbols2,3. One of the most prominent features of language is hierarchical structure4, which is also found in music5,6 and mathematics7. Current research attempts to address whether hierarchical structure exists in drawing. When we draw complex objects, such as a face, we draw part by part in a hierarchical manner guided by visual semantic knowledge8. More specifically, we predicted how hierarchical structure emerges in drawing as follows. Although the drawing order of the constituent parts composing the target object is different amongst individuals, some parts will be drawn in succession consistently, thereby forming chunks. These chunks of parts would then be further integrated with other chunks into superordinate chunks, while showing differential affinity amongst chunks. The integration of chunks to an even higher chunk level repeats until finally reaching the full object. We analysed the order of drawing strokes of twenty-two complex objects by twenty-five young healthy adult participants with a cluster analysis9 and demonstrated reasonable hierarchical structures. The results suggest that drawing involves a linear production of symbols with a hierarchical structure. From an evolutionary point of view, we argue that ancient engravings and paintings manifest Homo sapiens’ capability for hierarchical symbolic cognition.

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Macrophagic Inflammatory Response Next to Dental Implants with Different Macro- and Micro-Structure: An In Vitro Study

Applied Sciences ◽

10.3390/app11125324 ◽

2021 ◽

Vol 11 (12) ◽

pp. 5324

Author(s):

Maria Menini ◽

Francesca Delucchi ◽

Domenico Baldi ◽

Francesco Pera ◽

Francesco Bagnasco ◽

...

Keyword(s):

Inflammatory Response ◽

Dental Implants ◽

In Vitro Study ◽

Titanium Implants ◽

Implant Surface ◽

Bone Implant ◽

Optimal Outcomes ◽

Negative Controls ◽

Inflammatory Effect

(1) Background: Intrinsic characteristics of the implant surface and the possible presence of endotoxins may affect the bone–implant interface and cause an inflammatory response. This study aims to evaluate the possible inflammatory response induced in vitro in macrophages in contact with five different commercially available dental implants. (2) Methods: one zirconia implant NobelPearl® (Nobel Biocare) and four titanium implants, Syra® (Sweden & Martina), Prama® (Sweden & Martina), 3iT3® (Biomet 3i) and Shard® (Mech & Human), were evaluated. After 4 h of contact of murine macrophage cells J774a.1 with the implants, the total RNA was extracted, transcribed to cDNA and the gene expression of the macrophages was evaluated by quantitative PCR (qPCR) in relation to the following genes: GAPDH, YWHAZ, IL1β, IL6, TNFα, NOS2, MMP-9, MMP-8 and TIMP3. The results were statistically analyzed and compared with negative controls. (3) Results: No implant triggered a significant inflammatory response in macrophages, although 3iT3 exhibited a slight pro-inflammatory effect compared to other samples. (4) Conclusions: All the samples showed optimal outcomes without any inflammatory stimulus on the examined macrophagic cells.

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Section plane selection influences the results of histomorphometric studies: the example of dental implants

Biomedical Engineering / Biomedizinische Technik ◽

10.1515/bmt-2012-0015 ◽

2012 ◽

Vol 57 (5) ◽

Cited By ~ 8

Author(s):

Sigmar Kopp ◽

Mareike Warkentin ◽

Ferenc Öri ◽

Peter Ottl ◽

Günther Kundt ◽

...

Keyword(s):

Section Plane ◽

Section Thickness ◽

Implant Surface ◽

Bone Implant ◽

Osseointegrated Implants ◽

Section Technique ◽

Significant Difference ◽

Bone To Implant Contact ◽

The Mean ◽

Dependent Samples

AbstractThis study was designed to determine and statistically analyze bone-to-implant contact (BIC) values for human specimens segmented in at least two different locations.Samples of human bone with fractured osseointegrated implants were obtained from six patients. Sections were prepared, dehydrated, and resin infiltrated. Undecalcified bone sections were produced using the thin-section technique according to Donath, ultimately obtaining a section thickness of approximately 20 μm. Fifteen specimens were available for histomorphometry. The bone sections were digitized and analyzed. The bone-to-metal contact (BMC) parameter was determined histomorphometrically. The BMC was returned in terms of the visibly bone-covered implant surfaces as a percentage of the total implant surface shown.The values obtained for the six implants were arranged as six maximum-distance pairs and tested for significance using the t-test for dependent samples. The mean difference in BIC was 11.69±9.79%. The two-sided test showed a significant difference (p=0.033).The accidental or deliberate choice of section plane for a bone-implant block has an influence on the BIC value. To make BIC values more comparable, a standardization of section planes is desirable.

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