Rough Titanium Surfaces Research Articles

Effects on the Titanium Implant Surface by Different Hygiene Instrumentations: A Narrative Review.

Peri-implant disease is usually caused by the accumulation of dental biofilm around the implant, and this biofilm can irradiate the gingiva tissue, which leads to inflammation and, more severely, to a deterioration of the bone structure. There is a concern regarding the removal of biofilm from the implant surface by using different hygiene instruments. Some hygiene instruments may have some effect on the dental implant surface, resulting in roughening or damage to the implant surfaces. This study reviewed the effects of titanium implant surfaces on different hygiene instruments. A literature search was conducted from PubMed, ScienceDirect, and Scopus databases for articles published from 1992 to 2021. A total of 19 full-text papers with keywords of interest that met all the eligibility criteria were selected. Surface roughness was evaluated with a scanning electron microscope and also using a profilometer, laser scanning, scanning probe, and atomic force microscopes. A metal curette produced a roughened surface on the titanium implant, but a plastic curette did not alter the surface. Instrumentation with rubber cups left the surface unchanged and appeared to smoothen the surface, whereas the air-powder abrasive instrumentation altered the surface with the presence of micro pits and pores. A conventional metal ultrasonic scaler showed significant surface topographical changes and scratches on both titanium surfaces, as a diode laser, light-emitting diode (LED), and laser treatment did not show any alteration on the rough and smooth titanium surfaces. Thus, a non-metallic instrument such as a plastic curette, rubber cups, and novel technology including diode laser, LED, and laser treatment is appropriate and can be used for debridement on smooth and machined titanium implant surfaces as well as sandblasted and acid-etched (SLA), titanium plasma-sprayed (TPS), and resorbable blasted media (RBM) surfaces. The use of metallic instruments should be avoided, and it is not recommended.

The effect of surface material, roughness and wettability on the adhesion and proliferation of Streptococcus gordonii, Fusobacterium nucleatum and Porphyromonas gingivalis☆

Dental implants are inevitably exposed to bacteria in oral cavity. Understanding the colonization of bacteria on implant surface is necessary to prevent bacteria-related inflammation surrounding dental implants. The purpose of this study was to investigate the effect of surface properties on biofilm formation on the implant surface. One early colonizer, Streptococcus gordonii (S. gordonii), and two late colonizers, Fusobacterium nucleatum (F. nucleatum) and Porphyromonas gingivalis (P. gingivalis), were grown on the titanium and zirconia surfaces with two types of surface roughness for 24 and 72h. Each bacterial biofilm on specimens was quantified using crystal violet assay and observed by scanning electron microscopy. S. gordonii formed more biofilm on the titanium surface than zirconia at the same roughness and more biofilm on the rough surface than smooth one of the same materials at 24 and 72h of incubation. F. nucleatum adhered on all the surfaces at 24h and proliferated actively on the surfaces except smooth zirconia at 72h. P. gingivalis proliferated vigorously on the surfaces at 72h while it scarcely adhered at 24h. There was no consistent correlation between contact angle and biofilm formation of the three bacteria. The three bacteria proliferated most on the rough titanium surface and least on the smooth zirconia surface. In addition, the proliferation was affected by the bacterial species as well as the surface properties.

Canonical Wnt signaling enhances pro-inflammatory response to titanium by macrophages

Biomaterial characteristics like surface roughness and wettability can determine the phenotype of macrophages following implantation. We have demonstrated that inhibiting Wnt ligand secretion abolishes macrophage polarization in vitro and in vivo; however, the role of canonical Wnt signaling in macrophage activation in response to physical and chemical biomaterial cues is unknown. The aim of this study was to understand whether canonical Wnt signaling affects the response of macrophages to titanium (Ti) surface roughness or wettability in vitro and in vivo. Activating canonical Wnt signaling increased expression of toll-like receptors and interleukin receptors and secreted pro-inflammatory cytokines and reduced anti-inflammatory cytokines on Ti, regardless of surface properties. Inhibiting canonical Wnt signaling reduced pro-inflammatory cytokines on all Ti surfaces and increased anti-inflammatory cytokines on rough or rough-hydrophilic Ti. In vivo, activating canonical Wnt signaling increased total macrophages, pro-inflammatory macrophages, and T cells and decreased anti-inflammatory macrophages on both smooth and rough-hydrophilic implants. Functionally, canonical Wnt activation increases pro-inflammatory macrophage response to cell and cell-extracellular matrix lysates. These results demonstrate that activating canonical Wnt signaling primes macrophages to a pro-inflammatory phenotype that affects their response to Ti implants in vitro and in vivo.

Energy drinks alter the surface morphology and roughness of composites, fissure sealants and titanium: An in vitro study

ObjectivesThe influence of energy drinks on dental materials are relatively under addressed. Our aim was to investigate the effect of energy drinks on dental materials used intraorally in young individuals. Commonly used preventive, restorative, and orthodontic materials were tested in vitro. MethodsThe effect of two commercially available energy drinks (HELL, BURN) was investigated on different dental materials: machined, anodized Titanium (grade 5: Ti6Al4V) and composites (Grandio Seal, VOCO; Filtek Z250, 3M ESPE; Estelite SQ, TOKUYAMA). The roughness (Ra) and morphological changes were examined by atomic force microscopy (AFM) and scanning electron microscopy (SEM). ResultsAFM and SEM revealed significant differences in the Ra and morphology of the samples. AFM results for the machined and anodized titanium samples showed that the two energy drinks modified the surface roughness differently; BURN changed the roughness of machined samples significantly, while anodized discs were not altered significantly by the two energy drinks. In case of composite samples there was no significant difference for the Estelite SQ, relative low differences for the Filtek Z250 and significant changes in the morphology and surface roughness of Grandio Seal. SignificanceOn all tested materials, changes in the surface roughness and morphology were more or less detected, proving energy drinks do in fact have a harmful effect. It can be concluded that material erosion depends on the material composition and particle arrangement. Where the surface is characterized by a regular, uniform particle arrangement, energy drinks are less able to influence the roughness, while for samples where the surface is rich in aggregates, the material erodes the surface much more easily.

In-Vitro Phenotypic Response of Human Osteoblasts to Different Degrees of Titanium Surface Roughness.

Objectives: This study aimed to investigate human osteoblast (HOB) responses towards different degrees of titanium (Ti) implant surface roughness. Methods: Four degrees of Ti surface roughness were investigated on a micrometer roughness scale: smooth (S: 0.08–0.1 µm), minimally rough (MM: 0.3–0.5 µm), moderately rough (MR: 1.2–1.4 µm), and rough (R: 3.3–3.7 µm). HOB cells were cultured, expanded, and maintained according to the supplier’s protocol. Cell proliferation and cytotoxicity were assessed at day 1, 3, 5, and 10 using alamarBlue and lactate dehydrogenase colorimetric assays. Data were analyzed with one-way ANOVA, two-way ANOVA, and Tukey’s post hoc test (p = 0.05 for all tests). Results: There was no significant difference in the cell proliferation or cytotoxicity of the HOB cells in contact with the different degrees of Ti surface roughness. There was, however, a significant time effect on cell proliferation (p < 0.0001) with different exposure durations for each roughness degree. Furthermore, a positive correlation (non-significant) between proliferation and cytotoxicity was observed for all investigated degrees of surface roughness. Conclusion: All investigated roughness degrees showed comparable HOB proliferation, with the MR surface presenting the highest percentage, followed by the R, MM, ad S, surfaces, respectively. The S surface showed the highest cytotoxic effect on HOBs; however, it did not reach the cytotoxic level suggested by the ISO for any medical device to be considered cytotoxic.

In-Vitro Phenotypic Response of Human Osteoblasts to Different Titanium Surface Roughness

In-Vitro Phenotypic Response of Human Osteoblasts to Different Titanium Surface Roughness

A systematic review on neutrophils interactions with titanium and zirconia surfaces: Evidence from in vitro studies.

ObjectivesThis systematic review aimed to assess in vitro studies that evaluated neutrophil interactions with different roughness levels in titanium and zirconia implant surfaces.Material and MethodsAn electronic search for literature was conducted on PubMed, Embase, Scopus, and Web of Science and a total of 14 studies were included. Neutrophil responses were assessed based on adhesion, cell number, surface coverage, cell structure, cytokine secretion, reactive oxygen species (ROS) production, neutrophil activation, receptor expression, and neutrophil extracellular traps (NETs) release. The method of assessing the risk of bias was done using the toxicological data reliability assessment tool (TOXRTOOL).ResultsTen studies have identified a significant increase in neutrophil functions, such as surface coverage, cell adhesion, ROS production, and NETs released when interacting with rough titanium surfaces. Moreover, neutrophil interaction with rough–hydrophilic surfaces seems to produce less proinflammatory cytokines and ROS when compared to naive smooth and rough titanium surfaces. Regarding membrane receptor expression, two studies have reported that the FcγIII receptor (CD16) is responsible for initial neutrophil adhesion to hydrophilic titanium surfaces. Only one study compared neutrophil interaction with titanium alloy and zirconia toughened alumina surfaces and reported no significant differences in neutrophil cell count, activation, receptor expression, and death.ConclusionsThere are not enough studies to conclude neutrophil interactions with titanium and zirconia surfaces. However, different topographic modifications such as roughness and hydrophilicity might influence neutrophil interactions with titanium implant surfaces.

Efficiency of biofilm removal by combination of water jet and cold plasma: an in-vitro study.

BackgroundPeri-implantitis therapy is a major problem in implantology. Because of challenging rough implant surface and implant geometry, microorganisms can hide and survive in implant microstructures and impede debridement. We developed a new water jet (WJ) device and a new cold atmospheric pressure plasma (CAP) device to overcome these problems and investigated aspects of efficacy in vitro and safety with the aim to create the prerequisites for a clinical pilot study with these medical devices.MethodsWe compared the efficiency of a single treatment with a WJ or curette and cotton swab (CC) without or with adjunctive use of CAP (WJ + CAP, CC + CAP) to remove biofilm in vitro from rough titanium discs. Treatment efficacy was evaluated by measuring turbidity up to 72 h for bacterial re-growth or spreading of osteoblast-like cells (MG-63) after 5 days with scanning electron microscopy. With respect to application safety, the WJ and CAP instruments were examined according to basic regulations for medical devices.ResultsAfter 96 h of incubation all WJ and CC treated disks were turbid but 67% of WJ + CAP and 46% CC + CAP treated specimens were still clear. The increase in turbidity after WJ treatment was delayed by about 20 h compared to CC treatment. In combination with CAP the cell coverage significantly increased to 82% (WJ + CAP) or 72% (CC + CAP), compared to single treatment 11% (WJ) or 10% (CC).ConclusionThe newly developed water jet device effectively removes biofilm from rough titanium surfaces in vitro and, in combination with the new CAP device, biologically acceptable surfaces allow osteoblasts to grow. WJ in combination with CAP leads to cleaner surfaces than the usage of curette and cotton swabs with or without subsequent plasma treatment. Our next step will be a clinical pilot study with these new devices to assess the clinical healing process.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12903-022-02195-1.

Investigating the effects of abrasive water jet machining parameters on surface integrity, chemical state in machining of Ti-6Al-4V

This study examined into the surface roughness and microhardness of titanium (Ti6Al4V) alloy caused by the abrasive waterjet milling (AWJM) process. Waterjet pressure (WJP), stand-off distance (SOD), and abrasive flow rate (AFR) were studied on surface roughness and microhardness in three distinct regions: the initial damage region (IDR), the smooth cutting region (SCR) and the rough cutting region (RCR). X-Ray Diffraction was used to examine the lattice strain, crystallite size, and phase composition of abrasive waterjet machined samples. WJP is discovered to be a useful factor in reducing surface roughness, increasing striations, and decreasing waviness on the AWJM's surface. The higher hardness is caused by the material's permanent plastic deformation during the AWJM process. The FWHM of AWJ machined samples is reduced, and the presence of TiOxCx increases the crystallite size during the AWJM process. In relation to surface deformation, the AWJM causes severe plastic deformation (SPD), resulting in continuous internal oxide formation.

Effects of Titanium Implant Surface Topology on Bone Cell Attachment and Proliferation in vitro.

PurposeTitanium is commonly used for implants because of its corrosion resistance and osseointegration capability. It is well known that surface topology affects the response of bone tissue towards implants. In vivo studies have shown that in weeks or months, bone tissue bonds more efficiently to titanium implants with rough surfaces compared to smooth surfaces. In addition, stimulating early endosseous integration increases the long-term stability of bone-implants and hence their clinical outcome. Here, we evaluated the response of human MG-63 osteoblast-like cells to flat and solid, compared to rough and porous surface topologies in vitro 1–6 days post seeding. We compared the morphology, proliferation, and attachment of cells onto three smooth surfaces: tissue culture (TC) plastic or microscope cover glasses, machined polyether-ether-ketone (PEEK), and machined solid titanium, to cells on a highly porous (average Ra 22.94 μm) plasma-sprayed titanium surface (composite Ti-PEEK spine implants).MethodsWe used immuno-fluorescence (IF) and scanning electron microscopy (SEM), as well as Live/Dead and WST-1 cell proliferation assays.ResultsSEM analyses confirmed the rough topology of the titanium implant surface, compared to the smooth surface of PEEK, solid titanium, TC plastic and cover glasses. In addition, SEM analyses revealed that MG-63 cells seeded onto smooth surfaces (solid titanium, PEEK) adopted a flat, planar morphology, while cells on the rough titanium surface adopted an elongated morphology with numerous filopodial and lamellipodial extensions interacting with the substrate. Finally, IF analyses of focal adhesions (vinculin, focal adhesion kinase), as well as proliferation assays indicate that MG-63 cells adhere less and proliferate at a slower rate on the rough than on a smooth titanium surface.ConclusionThese observations suggest that bone-forming osteoblasts adhere less strongly and proliferate slower on rough compared to smooth titanium surfaces, likely promoting cell differentiation, which is in agreement with other porous implant materials.

A novel dual surface modification on titanium in dental use: Characterization and topography

This laboratory study aimed to compare, contrast, and evaluate the effect of a novel dual surface modification method on the adhesion strength of resin composite cement to titanium. C.p.‐2 grade titanium samples were silica‐coated, etched with HNO3(69vol %) or a blend of HCl (35vol %) and H3PO4 (85vol %), for 1 h at 80°C. Surface roughness was measured by surface roughness profilometry, topographic analysis by scanning electron microscopy (SEM), atomic force microscopy (AFM), and surface analyses by energy dispersive X‐ray spectroscopy (EDX), X‐ray photoelectron spectroscopy (XPS). Silanization of all specimens was carried out after SEM, EDX, and AFM analysis, before enclosed mold microshear bond strength testing (EM‐μSBS). Adhesion strengths were measured after artificial ageing: 1 day, 1 week, 4 weeks, and 8 weeks by EM‐μSBS testing and failure mode analysis by optical microscopy. Polished titanium was used as a control. The highest surface roughness was observed in titanium samples treated with silica‐coating + HCl‐H3PO4 etching. The elemental composition confirmed the presence of Ti, O, C, with Si and Al in samples treated with silica‐coating. A gradual decrease in EM‐μSBS values was observed in all titanium samples with adhesive and cohesive failure modes. The novel dual surface modification method applied in this study suggests that silica‐coating + HCl‐H3PO4etching strongly affects titanium surface topography and roughness. The presence of Si on silica‐coated surface modified titanium before silanization with an experimental silane has a positive effect on the EM‐μSBS of titanium samples treated with silica‐coating only or silica‐coating + HNO3 etching.

Efficacy of Combined Mechanical and Chemical Decontamination Treatments on Smooth and Rough Titanium Surfaces and Their Effects on Osteoconduction: An Ex Vivo Study.

The aim of this ex vivo study was to assess the ability to remove oral biofilm by different combinations of mechanical and chemical treatments on smooth and rough titanium surfaces, as well as their impact on osteoconduction. Forty-eight sandblasted acid-etched (SLA) and 48 machined titanium disks were contaminated with oral bacterial biofilm and exposed to the following treatments: (1) titanium brush (TB), (2) TB + 40% citric acid (CA), (3) TB + 5.25% sodium hypochlorite (NaOCl), (4) air polishing with glycine powder (AP), (5) AP + 40% CA, and (6) AP + 5.25% NaOCl. Residual bacteria and chemical contamination were assessed using viable bacterial count assay, scanning electron microscopy (SEM), and x-ray spectroscopy (XPS). Human primary osteoblast (hOB) adhesion and osteocalcin (OC) release were also evaluated. The microbiologic, SEM, and XPS analysis indicate a higher biofilm removal efficiency of combined mechanical-chemical treatments compared with exclusively mechanical approaches, especially on SLA surfaces. SEM analysis revealed significant alterations of surface microtopography on the disks treated with TB, while no changes were observed after AP treatment. OC release by hOBs was mainly decreased on disks treated with CA and NaOCl. The combination of mechanical and chemical treatments provides effective oral biofilm removal on both SLA and machined implant surfaces. NaOCl and CA may have a negative effect on osteoblasts cultured on SLA samples.

Influence of dental abrasives on surface roughness, gloss, and color of titanium.

The influence of three dental abrasives on the surface roughness, glossiness, and color of titanium (Ti) after mechanical polishing was investigated. The specimens were divided into groups, referred to as SM, SR, and TP, to distinguish the different polishing processes. SM: rubber polishing using a rubber point containing SiC abrasive particles at 20,000 rpm, followed by gloss polishing; SR: rubber polishing using a rubber point containing Al2O3 abrasive particles at 20,000 rpm, followed by gloss polishing; TP: rubber polishing using a rubber point containing TiO2 abrasive particles at 6,000 rpm, followed by gloss polishing. Gloss polishing was carried out at 10,000 rpm using a leather buffing wheel. Measurements to evaluate the surface conditions of Ti were performed after each polishing process. There were no significant differences in the Ra and glossiness values between the SM and TP groups; these specimens were not as smooth and glossy as the SR group. The SM group showed relatively high values of lightness and chroma after gloss polishing. Rubber polishing with abrasives containing SiC or TiO2 particles before gloss polishing did not achieve appropriate surface conditions on Ti.

Effect of Yb: Fiber laser on surface roughness and wettability of titanium

Background/Aim: In recent years, the role of computer aided design (CAD) and computer aided manufacturing (CAM) in dentistry has increasingly become important. However, the influence of different Yb: fiber laser applications on surface roughness of CAD/CAM implant has rarely been studied. The aim of this study is to investigate the effect of different Yb: fiber laser parameters on the surface roughness of CAD/CAM titanium. Material and Methods: Titanium samples, produced by CAD/CAM, were divided into 11 groups according to laser parameters such as scanning types (ST), application angles (AA) and hatch interval (HI). The surface roughness of CAD/CAM titanium was examined for each group. Wettability contact angles (CA) were also determined. Results: The highest surface roughness (43 mm) value was obtained for Group 10 (three-ways ST, 60o AA, 0.07mm HI). The lowest value (2.77 mm) after control group was obtained for Group 6. Surface roughness values, for Group 3, Group 9 and Group 10 were significantly higher than for the other groups (P= 0.000). In contact angle evaluations, the highest contact angle (144o) was observed in Group 10, while the lowest (95o) was observed in control group. Conclusions: Surface roughness was dependent on mixed effect of the laser application parameters. Three-ways ST, 60o AA, 0.07mm HI provided highest surface roughness and wettability contact angles. The surface roughness values of one-way ST, 0.06 mm HI, two-ways HT, 45o AA and 0.08 mm HI and three-ways ST, 60o AA and 0.07 mm HI were significantly higher than for the other groups (P=0.000).

Early Biofilm Formation on Rough and Smooth Titanium Specimens: a Systematic Review of Clinical Studies.

ABSTRACTObjectivesThere is a concern whether the enhancement on implant surface roughness is responsible for higher biofilm formation, which acts as an aetiological factor for peri-implant diseases. The aim of the present systematic review was to answer the following question: “Are rough surfaces more susceptible to early biofilm formation when compared to smoother surfaces on titanium specimens?”.Material and MethodsThe research was performed on PubMed, Web of Science and Scopus, up to August 2021. Eligibility criteria included studies that analysed human biofilm formation on titanium specimens with distinct surface roughness (smooth vs minimally, moderate, or rough) over the experimental times of 1 or 3 days. Roughness average (Ra) and biofilm analysis parameters were extracted from selected articles. Risk of bias was evaluated using the Checklist for Quasi-Experimental Studies.ResultsOf 5286 papers, 5 were included and analysed. Smooth titanium surfaces included machined and anodized titanium/Ti-6Al-4V; machined and acid etched TiZr. Minimally, moderately, or rough surfaces comprised titanium and titanium alloys (TiZr, Ti-6Al-4V), that received surface treatments (anodization, acid-etching, blasting, hydroxyapatite-coating). No statistically significant difference on biofilm formation on rough and smooth titanium surfaces was reported by 3 studies, while more contamination on rough titanium surfaces was stated by 2 investigations. An isolated smooth surface has also been associated to higher contamination. Moderate to high quality methodological assessment of studies were identified.ConclusionsIt is not possible to assume that rough surfaces are more susceptible to early biofilm formation than smooth titanium surfaces. Additional studies are required to study this multifarious interaction.

Alterations to Titanium Surface Depending on the Fluorides and Abrasives in Toothpaste.

Fluoride and abrasives in toothpastes may cause corrosion and deterioration of the titanium used for implants and other prostheses. The purpose of this study was to investigate how the presence or absence and types of fluoride and abrasives affected the titanium surface texture. Brushing with toothpastes was performed on pure-titanium discs using an abrasive testing machine. Unprocessed titanium discs without brushing were used as control samples. Surface roughness, color, and gloss of titanium were measured and the differences compared with the control were analyzed. Additionally, titanium surfaces and abrasives in toothpastes were observed using a scanning electron microscope to compare the surface texture of each sample. Some toothpastes (abrasive+) significantly increased the difference in surface roughness, color, and gloss, compared with ultrapure water. Toothpaste (fluoride+/abrasive+) that had many polygonal abrasive particles led to the largest color differences and exhibited notable scratches and a larger number of contaminant- or corrosion-like black spots. In contrast, brushing with toothpaste without fluoride or abrasives (fluoride−/abrasive−) caused little change to the titanium surface. These results suggest that both fluoride and abrasives in toothpaste used for brushing may be factors that affect surface texture and corrosion resistance of titanium.

Modulating autophagy by strontium-doped micro/nano rough titanium surface for promotion of osteogenesis and inhibition of osteoclastogenesis

Although it has been demonstrated that implant surfaces treated with strontium (Sr) promote osseointegration, the underlying intracellular mechanism remains unknown. Autophagy is a vital intracellular degradation mechanism that plays an essential role in maintaining bone homeostasis. Therefore, while designing implant biomaterials, it is critical to consider the autophagy mechanism. In this study, we fabricated Sr-doped micro/nano rough titanium implant surface by hydrothermal treatment (SLA+Sr). The in vitro results revealed that the SLA+Sr surface promoted osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) via autophagy activation. The SLA+Sr surface, on the other hand, inhibited osteoclast differentiation by downregulating autophagy. Additionally, in vivo, the SLA+Sr implant improved osseointegration, inhibited osteoclastogenesis, and upregulated autophagy levels in surrounding bone tissue cells. Our findings established a novel centralized mechanism by which SLA+Sr regulated osteogenesis and osteoclastogenesis during the osseointegration process through autophagy regulation. Moreover, endowing implants with the ability to modulate autophagy may be a promising strategy for enhancing implant osseointegration in the future translational medicine field.

Evaluation of the Effect of Different Types of Fluoride on Tensile Properties and Surface Roughness of Different Titanium-Based Archwires: An In vivo Study.

Objectives:The purpose of the study was to evaluate the effect of different types of fluoride on tensile properties and surface roughness of titanium based archwires clinically.Materials and methods:Three groups of archwires, namely nickel–titanium (NiTi), heat activated NiTi, and TMA was evaluated clinically. Each group comprised four subgroups, namely as received group, nonfluoride control group, APF gel group (received one application of 1.23% APF gel), and sodium fluoride mouthwash group (patients rinsed twice daily with 0.2% sodium fluoride mouthwash). All the archwires were removed after 3 weeks of clinical use and evaluated for surface roughness with three dimensional optical profiler. Tensile strength and elongation rate was determined with Instron universal testing machine.Results:NiTi, heat activated NiTi, and TMA archwires with APF gel application showed the highest reduction in tensile strength and elongation rate and highest value for surface roughness, followed by sodium fluoride mouthwash group and finally wires without fluoride application. NiTi wires had the highest reduction in tensile strength with APF gel followed by heat activated NiTi and TMA.Conclusion:APF gel with highest concentration of fluoride caused most degradation in the tensile properties and surface roughness of titanium based arch wires.

Histologic and Histomorphometric Evaluation of a New Bioactive Liquid BBL on Implant Surface: A Preclinical Study in Foxhound Dogs.

Background: Bioactive chemical surface modifications improve the wettability and osseointegration properties of titanium implants in both animals and humans. The objective of this animal study was to investigate and compare the bioreactivity characteristics of titanium implants (BLT) pre-treated with a novel bone bioactive liquid (BBL) and the commercially available BLT-SLA active. Methods: Forty BLT-SLA titanium implants were placed in in four foxhound dogs. Animals were divided into two groups (n = 20): test (BLT-SLA pre-treated with BBL) and control (BLT-SLA active) implants. The implants were inserted in the post extraction sockets. After 8 and 12 weeks, the animals were sacrificed, and mandibles were extracted, containing the implants and the surrounding soft and hard tissues. Bone-to-implant contact (BIC), inter-thread bone area percentage (ITBA), soft tissue, and crestal bone loss were evaluated by histology and histomorphometry. Results: All animals were healthy with no implant loss or inflammation symptoms. All implants were clinically and histologically osseo-integrated. Relative to control groups, test implants demonstrated a significant 1.5- and 1.7-fold increase in BIC and ITBA values, respectively, at both assessment intervals. Crestal bone loss was also significantly reduced in the test group, as compared with controls, at week 8 in both the buccal crests (0.47 ± 0.32 vs 0.98 ± 0.51 mm, p < 0.05) and lingual crests (0.39* ± 0.3 vs. 0.89 ± 0.41 mm, p < 0.05). At week 12, a pronounced crestal bone loss improvement was observed in the test group (buccal, 0.41 ± 0.29 mm and lingual, 0.54 ± 0.23 mm). Tissue thickness showed comparable values at both the buccal and lingual regions and was significantly improved in the studied groups (0.82–0.92 mm vs. 33–48 mm in the control group). Conclusions: Relative to the commercially available BLT-SLA active implants, BLT-SLA pre-treated with BBL showed improved histological and histomorphometric characteristics indicating a reduced titanium surface roughness and improved wettability, promoting healing and soft and hard tissue regeneration at the implant site.

Effects of strontium-incorporated micro/nano rough titanium surfaces on osseointegration via modulating polarization of macrophages

Macrophages perform multiple functions in both inflammation and wound healing, and are one of the fore front cells during implant osseointegration that influence subsequent process. Essential trace element modification may effectively modulate titanium implant surface biological properties. In this work, strontium (Sr) incorporated micro/nano rough titanium surfaces (Sr-SLA) was fabricated by hydrothermal treatment, and immunoreaction of macrophages was further investigated. In vitro results revealed that Sr doping inhibited inflammatory response of macrophages, further attenuated the inhibitory effect on following bone marrow derived cells (BMSCs) osteogenic differentiation. The regulation of macrophages by Sr-SLA likely involved ERK signaling pathway. Consistently, the in vivo study showed that compared with titanium surface sand-blasted with large grit and double acid-etched (SLA) implants, Sr-SLA implants could enhance new bone formation accompanied with more alternatively activated M2 macrophages infiltration and less classically activated M1 macrophages infiltration. These results reveal the immunomodulatory ability of Sr-SLA of adjusting the functional status of macrophages through inhibiting M1 polarization while promoting M2 polarization.