Sandblasted/acid-etched Research Articles

Clinical outcomes and supragingival microbiota analysis around dental implants and teeth in patients with a history of periodontitis: a preliminary study of 6 months follow-up.

To investigate the supragingival microbiome surrounding dental implants and neighbouring tooth in periodontitis history and periodontally healthy patients. Subjects with a history of periodontitis (test) and periodontally healthy subjects (control) received one of two types of dental implants with different surface characteristics: sandblasted acid-etched (SLA) or precision dimension laser-treated (PDL). Periodontal clinical measurements were collected at baseline (V1), 3 months after implant placement (V4), at zirconia crown placement (V6) and 3 months after zirconia crown placement (V8). Supragingival bacterial microbiota was studied using Illumina MiSeq sequencing. Supragingival microbial community on SLA implants in test group significantly differed to control group at V8 (p < 0.05). A longitudinal shift displaying microbial dysbiosis occurred on SLA implants (p < 0.05) and adjacent teeth (p < 0.05) among test patients from V6 to V8. On PDL implants and the adjacent tooth, no significant difference between test and control groups from V6 to V8 (p > 0.05). Co-occurrence network in test group of SLA implants and the adjacent tooth at V8 showed increased disease-associated bacteria and reduced health-associated bacteria. Health-associated bacteria were dominant in control group of SLA implants at V8. The surface characteristics and prosthetic components of dental implants may be important risk factors in patients with a history of periodontitis. Dysbiosis of supragingival microbiome may predispose dental implants to peri-implant diseases. Thus, a strict supportive periodontal care plan is imperative to prevent early onset of biological complications.

A randomized controlled trial of immediate implant placement comparing hydroxyapatite nano-coated and uncoated sandblasted/acid-etched implants using a digital surgical guide

PurposeThis study evaluated the implant stability, volumetric changes, and patient-reported outcome measures (PROMs) of hydroxyapatite (HA) nano-coated sandblasted/acid-etched (SLA) implants compared to uncoated SLA implants.MethodsForty patients were recruited and randomly allocated to HA nano-coated SLA group (test, n = 20) and uncoated SLA group (control, n = 20) using single-blinded/block randomization. Implants were immediately placed in maxillary posterior region using a digital surgical guide. Insertion torque and implant stability quotient (ISQ) were measured at implant surgery and 1, 2, 3, and 4 months postoperatively. Intraoral scans, PROMs and soft tissue inflammation data were collected, and multivariable linear regression analysis of ISQ was performed.ResultsIn total, 48 implants (test; n = 24, control; n = 24) in 37 patients (test; n = 19, control; n = 18) were analyzed. Despite no significant between-group difference at surgery, the test group showed higher ISQ values than the control group at 2 (76.53 ± 4.17 vs. 71.32 ± 4.79, p < 0.01), 3 (77.45 ± 4.41 vs. 73.85 ± 4.69, p < 0.05), and 4 months (79.08 ± 2.96 vs. 73.43 ± 3.52, p < 0.0001) postoperatively. There were no significant differences in linear and volumetric changes, PROMs, and soft tissue inflammation analysis between two groups. The ISQ at implant surgery was influenced by age and diabetes mellitus (DM) at the implant level and DM and predicted total bone-to-implant contact area at the patient level.ConclusionHA nano-coated SLA implants promoted favorable immediate implants stability during early osseointegration phase compared to uncoated SLA implants, but displayed similar dimensional changes, PROMs, and soft tissue inflammation outcomes.Trial registrationClinical Research Information Service (CRIS), KCT0006364. Registered 21 July 2021, https://cris.nih.go.kr/cris/search/detailSearch.do?seq=24221&search_page=L.

Efficacy of a Solution Containing 33% Trichloroacetic Acid and Hydrogen Peroxide in Decontaminating Machined vs. Sand-Blasted Acid-Etched Titanium Surfaces.

This in vitro study assessed the efficacy of a solution containing 33% trichloroacetic acid (CCl3COOH; TCA) and hydrogen peroxide (H2O2) in decontaminating machined (MAC) and sand-blasted acid-etched (SBAE) titanium surfaces. A total of 80 titanium disks were prepared (40 MAC and 40 SBAE). Streptococcus sanguinis and Enterococcus faecalis strains were incubated on 36 samples, while the remaining 44 were kept as controls. Roughness analysis and scanning electron microscopy were used to evaluate the surface features before and after TCAH2O2 treatment. The viability of human adipose-derived mesenchymal stem cells (ASCs) after TCAH2O2 decontamination was assessed with a chemiluminescent assay along with cell morphology through fluorescent staining. TCAH2O2 preserved the surface topography of MAC and SBAE specimens. It also effectively eradicated bacteria on both types of specimens without altering the surface roughness (p > 0.05). Also, no significant differences in protein adsorption between the pristine and TCAH2O2-treated surfaces were found (p = 0.71 and p = 0.94). While ASC proliferation remained unchanged on MAC surfaces, a decrease was observed on the decontaminated SBAE specimens at 24 and 48 h (p < 0.05), with no difference at 72 h (p > 0.05). Cell morphology showed no significant changes after 72 h on both surface types even after decontamination. This study suggests TCAH2O2 as a promising decontamination agent for titanium surfaces, with potential implications for peri-implant health and treatment outcomes.

Influence of Topography and Composition of Commercial Titanium Dental Implants on Cell Adhesion of Human Gingiva-Derived Mesenchymal Stem Cells: An In Vitro Study

The topography and composition of dental implant surfaces directly impact mesenchymal cell adhesion, proliferation, and differentiation, crucial aspects of achieving osseointegration. However, cell adhesion to biomaterials is considered a key step that drives cell proliferation and differentiation. The aim of this study was to characterize characterize the topography and composition of commercial titanium dental implants manufactured with different surface treatments (two sandblasted/acid-etched (SLA) (INNO Implants, Busan, Republic of Korea; BioHorizonsTM, Oceanside, CA, USA) and two calcium phosphate (CaP) treated (Biounite®, Berazategui, Argentina; Zimmer Biomet, Inc., Warsaw, IN, USA)) and to investigate their influence on the process of cell adhesion in vitro. A smooth surface implant (Zimmer Biomet, Inc.) was used as a control. For that, high-resolution methodologies such as scanning electron microscopy (SEM), X-ray dispersive spectroscopy (EDX), laser scanning confocal microscopy (LSCM), and atomic force microscopy (AFM) were employed. Protein adsorption and retromolar gingival mesenchymal stem cells (GMSCs) adhesion to the implant surfaces were evaluated after 48 h. The adherent cells were examined by SEM and LSCM for morphologic and quantitative analyses. ANOVA and Tukey tests (α = 0.05) were employed to determine statistical significance. SEM revealed that INNO, BioHorizonsTM, and Zimmer implants have an irregular surface, whereas Biounite® has a regular topography consisting of an ordered pattern. EDX confirmed a calcium and phosphate layer on the Biounite® and Zimmer surfaces, and AFM exhibited different roughness parameters. Protein adsorption and cell adhesion were detected on all the implant surfaces studied. However, the Biounite® implant with CaP and regular topography showed the highest protein adsorption capacity and density of adherent GMSCs. Although the Zimmer implant also had a CaP treatment, protein and cell adhesion levels were lower than those observed with Biounite®. Our findings indicated that the surface regularity of the implants is a more determinant factor in the cell adhesion process than the CaP treatment. A regular, nanostructured, hydrophilic, and moderately rough topography generates a higher protein adsorption capacity and thus promotes more efficient cell adhesion.

Impact of surface characteristics on the peri-implant microbiome in health and disease.

Because little is known about the impact of implant surface modifications on the peri-implant microbiome, we aimed to examine peri-implant communities in various surface types in order to better understand the impact of these surfaces on the development of peri-implantitis (PI). One hundred and six systemically healthy individuals with anodized (AN), hydroxyapatite-coated (HA), or sandblasted acid-etched (SLA) implants that were >6 months in function were recruited and categorized into health (H) or PI. Peri-implant biofilm was analyzed using 16S rRNA gene sequencing and compared between health/disease and HA/SLA/AN using community-level and taxa-level metrics. Healthy implants did not demonstrate significant differences in clustering, alpha- or beta-diversity based on surface modification. AN and HA surfaces displayed significant differences between health and PI (p<0.05); however, such a clustering was not evident with SLA (p>0.05). AN and HA surfaces also differed in the magnitude and diversity of differences between health and PI. Six species belonging to the genera Shuttleworthia, Scardovia, and Prevotella demonstrated lower abundances in AN implants with PI, and 18 species belonging to the genera Fretibacterium, Tannerella, Treponema, and Fusobacterium were elevated, while in HA implants with PI, 20 species belonging to the genera Streptococcus, Lactobacillus, Veillonella, Rothia, and family Ruminococcaceae were depleted and Peptostreptococcaceae, Atopobiaceae, Veillonellaceae, Porphyromonadaceae, Desulfobulbaceae, and order Synergistales were enriched. Within the limitations of this study, we demonstrate that implant surface can differentially modify the disease-associated microbiome, suggesting that surface topography must be considered in the multi-factorial etiology of peri-implant diseases.

Sandblasted/Acid-Etched Titanium Surface Modified with Calcium Phytate Enhances Bone Regeneration in a High-Glucose Microenvironment by Regulating Reactive Oxygen Species and Cell Senescence.

Hyperglycemia in patients with diabetes affect osteoblast function, leading to abnormal bone metabolism and implant failure. Adequate bone volume surrounding an implant is essential for osseointegration, which can be improved by implant surface modifications. In this study, titanium surfaces were hydrothermally treated with a mixture of phytic acid (PA) and calcium hydroxide to produce a calcium-decorated surface. The control group comprised pure titanium with a sandblasted/acid-etched (SLA) surface. The elemental composition, hydrophilicity, surface roughness, and morphology of the titanium surfaces were examined. Evaluation of in vitro osteogenic differentiation ability in a high-glucose environment using alkaline phosphatase (ALP) staining, ALP activity assays, Alizarin Red S staining, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and immunofluorescence staining revealed that Ca-PA-modified SLA titanium surfaces can promote osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs). Evaluation of oxidative stress and aging using reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), and β-galactosidase staining revealed that Ca-PA-modified SLA titanium surfaces can reduce ROS production and ameliorate oxidative stress damage in hBMSCs. In vivo assessment of osteogenesis in a diabetic rat model revealed that Ca-PA coating promotes peri-implant osseointegration. Ca-PA-modified SLA titanium surface is a candidate for improving implant osseointegration in patients with diabetes.

Bone defect development in experimental canine peri-implantitis models: a systematic review

PurposeTo provide a systematic overview of preclinical research regarding bone defect formation around different implant surfaces after ligature-induced peri-implantitis models in dogs. Two focused questions were formulated: ‘How much bone loss can be expected after a certain time of ligature induced peri-implantitis?’ and ‘Do different implant types, dog breeds and study protocols differ in their extent of bone loss?’Materials and methodsA systematic literature search was conducted on four databases (MEDLINE, Web of Science, EMBASE and Scopus). Observations, which consisted of bone defects measured directly after ligature removal in canine models, were included and analysed. Two approaches were used to analyse the relatively heterogeneous studies that fulfilled the inclusion criteria. First, separate simple linear regressions were calculated for each study and implant surface, for which observations were available across multiple time points. Second, a linear mixed model was specified for the observations at 12 weeks after ligature initiation, and assessing the potential influencing factors on defect depth was explored using lasso regularisation.ResultsThirty-six studies with a total of 1082 implants were included after. Bone loss was determined at different time points, either with clinical measurements radiographically or histologically. Different implant groups [e.g. turned, sand-blasted-acid-etched (SLA), titanium-plasma-sprayed (TPS) and other rough surfaces] were assessed and described in the studies. A mean incremental defect depth increase of 0.08 mm (SD: −0.01–0.28 mm) per week was observed. After 12 weeks, the defect depths ranged between 0.7 and 5 mm. Based on the current data set, implant surface could not be statistically identified as an essential factor in defect depth after 12 weeks of ligature-induced peri-implantitis.ConclusionExpectable defect depth after a specific time of ligature-induced peri-implantitis can vary robustly. It is currently impossible to delineate apparent differences in bone loss around different implant surfaces.

Proteomic evaluation of human osteoblast responses to titanium implants over time.

Titanium is widely used in bone prostheses due to its excellent biocompatibility and osseointegration capacity. To understand the effect of sandblasted acid-etched (SAE) Ti implants on the biological responses of human osteoblast (HOb), their proteomic profiles were analyzed using nLC-MS/MS. The cells were cultured with the implant materials, and 2544 distinct proteins were detected in samples taken after 1, 3, and 7 days. Comparative analyses of proteomic data were performed using Perseus software. The expression of proteins related to EIF2, mTOR, insulin-secretion and IGF pathways showed marked differences in cells grown with SAE-Ti in comparison with cells cultured without Ti. Moreover, the proteomic profiles obtained with SAE-Ti were compared over time. The affected proteins were related to adhesion, immunity, oxidative stress, coagulation, angiogenesis, osteogenesis, and extracellular matrix formation functions. The proliferation, mineralization and osteogenic gene expression in HObs cultured with SAE-Ti were characterized in vitro. The results showed that the osteoblasts exposed to this material increase their mineralization rate and expression of COLI, RUNX2, SP7, CTNNB1, CAD13, IGF2, MAPK2, and mTOR. Overall, the observed proteomic profiles can explain the SAE-Ti osteogenic properties, widening our knowledge of key signaling pathways taking part in the early stages of the osseointegration process in this type of implantations.

Enhanced osteogenic differentiation of mesenchymal stem cells by surface lithium modification in a sandblasted/acid-etched titanium implant.

This study investigated the osteogenesis-related cell functions of osteoprogenitor cells modulated by surface chemistry modification using lithium (Li) ions in a current clinical oral implant surface in order to gain insights into the future development of titanium (Ti) implants with enhanced osteogenic capacity. Wet chemical treatment was performed to modify a sandblasted/acid-etched (SLA) Ti implant surface using Li ions. The osteogenesis-related cell response to the surface Li ion-modified SLA sample was evaluated using two kinds of murine bone marrow stem cells, bipotent ST2 cells and primary multipotent mesenchymal stem cells (MSCs). The modified surface exhibited the formation of an Li-containing Ti oxide layer with plate-like nanostructures. The Li-incorporated surface enhanced early cellular events, including spreading, focal adhesion formation and integrin mRNA expression (α2, α5, αv and β3), and accelerated osteogenic differentiation of bipotent ST2 cells compared with unmodified SLA surface. Surface Li modification significantly increased GSK-3β phosphorylation and suppressed β-catenin phosphorylation, and promoted the subsequent osteogenic differentiation of primary MSCs. These results indicate that surface chemistry modification of SLA implants by wet chemical treatment with Li ions induces a more favorable osseointegration outcome through the promotion of the osteogenic differentiation of bone marrow MSCs via the positive regulation of GSK-3β and β-catenin activity.

3D engineered human gingiva fabricated with electrospun collagen scaffolds provides a platform for in vitro analysis of gingival seal to abutment materials.

In order to advance models of human oral mucosa towards routine use, these models must faithfully mimic the native tissue structure while also being scalable and cost efficient. The goal of this study was to develop a low-cost, keratinized human gingival model with high fidelity to human attached gingiva and demonstrate its utility for studying the implant-tissue interface. Primary human gingival fibroblasts (HGF) and keratinocytes (HGK) were isolated from clinically healthy gingival biopsies. Four matrices, electrospun collagen (ES), decellularized dermis (DD), type I collagen gels (Gel) and released type I collagen gels (Gel-R)) were tested to engineer lamina propria and gingiva. HGF viability was similar in all matrices except for Gel-R, which was significantly decreased. Cell penetration was largely limited to the top layers of all matrices. Histomorphometrically, engineered human gingiva was found to have similar appearance to the native normal human gingiva except absence of rete pegs. Immunohistochemical staining for cell phenotype, differentiation and extracellular matrix composition and organization within 3D engineered gingiva made with electrospun collagen was mostly in agreement with normal gingival tissue staining. Additionally, five types of dental material posts (5-mm diameter x 3-mm height) with different surface characteristics were used [machined titanium, SLA (sandblasted-acid etched) titanium, TiN-coated (titanium nitride-coated) titanium, ceramic, and PEEK (Polyetheretherketone) to investigate peri-implant soft tissue attachment studied by histology and SEM. Engineered epithelial and stromal tissue migration to the implant-gingival tissue interface was observed in machined, SLA, ceramic, and PEEK groups, while TiN was lacking attachment. Taken together, the results suggest that electrospun collagen scaffolds provide a scalable, reproducible and cost-effective lamina propria and 3D engineered gingiva that can be used to explore biomaterial-soft tissue interface.

Osteogenic Differentiation of Human Mesenchymal Stem Cells Modulated by Surface Manganese Chemistry in SLA Titanium Implants.

The manganese (Mn) ion has recently been probed as a potential candidate element for the surface chemistry modification of titanium (Ti) implants in order to develop a more osteogenic surface with the expectation of taking advantage of its strong binding affinity to the integrins on bone-forming cells. However, the exact mechanism of how Mn enhances osteogenesis when introduced into the surface of Ti implants is not clearly understood. This study investigated the corrosion resistance and potential osteogenic capacity of a Mn-incorporated Ti surface as determined by electrochemical measurement and examining the behaviors of human mesenchymal stem cells (MSCs) in a clinically available sandblasted/acid-etched (SLA) oral implant surface intended for future biomedical applications. The surface that resulted from wet chemical treatment exhibited the formation of a Mn-containing nanostructured TiO2 anatase thin film in the SLA implant and improved corrosion resistance. The Mn-incorporated SLA surface displayed sustained Mn ion release and enhanced osteogenesis-related MSC function, which enhanced early cellular events such as spreading, focal adhesion, and mRNA expression of critical adhesion-related genes and promoted full human MSC differentiation into mature osteoblasts. Our findings indicate that surface Mn modification by wet chemical treatment is an effective approach to produce a Ti implant surface with increased osteogenic capacity through the promotion of the osteogenic differentiation of MSCs. The improved corrosion resistance of the resultant surface is yet another important benefit of being able to provide favorable osseointegration interface stability with an increased barrier effect.

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.

Efficacy of Er:YAG laser irradiation for decontamination and its effect on biocompatibility of different titanium surfaces

BackgroundErbium yttrium–aluminum–garnet (Er:YAG) laser have been shown to be suitable for decontamination of titanium surfaces at a wide range of energy settings, however, high intensity of laser irradiation destroy titanium surface and low intensity cannot remove enough microbial biofilm. The aim of this study was to investigate the optimal energy setting of Er:YAG laser for decontamination of sandblasted/acid-etched (SLA) and hydroxyapatite (HA) titanium surfaces.Material and methodsAfter supragingival biofilm construction in vivo, SLA and HA titanium discs were divided into three groups: blank control (BC, clean discs), experimental control (EC, contaminated discs) and experimental groups (EP, contaminated discs irradiated by Er:YAG laser at 40, 70, and 100 mJ/pulse). Scanning electron microscopy (SEM), live/dead bacterial fluorescent detection, and colony counting assay were used to detect the efficacy of laser decontamination. To investigate the effect of laser decontamination on titanium surface biocompatibility, MC3T3-E1 cell adhesion and proliferation activity were examined by SEM and CCK-8 assay.ResultsEr:YAG laser irradiation at 100 mJ/pulse removed 84.1% of bacteria from SLA titanium surface; laser irradiation at 70 and 100 mJ/pulse removed 76.4% and 77.85% of bacteria from HA titanium surface respectively. Laser irradiation improved MC3T3-E1 cell adhesion on both titanium surfaces. For SLA titanium discs, 100 mJ/pulse group displayed excellent cellular proliferation activity higher than that in BC group (P < 0.01). For HA titanium discs, 70 mJ/pulse group showed the highest activity comparable to BC group (P > 0.05).ConclusionsWith regards to efficient microbial biofilm decontamination and biocompatibility maintenance, Er:YAG laser at 100 mJ/pulse and 70 mJ/pulse are considered as the optimal energy settings for SLA titanium and HA titanium surface respectively. This study provides theoretical basis for the clinical application of Er:YAG laser in the treatment of peri-implantitis.

Greater Osseointegration Potential with Nanostructured Surfaces on TiZr: Accelerated vs. Real-Time Ageing.

Surface chemistry and nanotopography of dental implants can have a substantial impact on osseointegration. The aim of this investigation was to evaluate the effects of surface chemistry and nanotopography on the osseointegration of titanium-zirconium (TiZr; Roxolid®) discs, using a biomechanical pull-out model in rabbits. Two discs each were placed in both the right and left tibiae of 16 rabbits. Five groups of sandblasted acid etched (SLA) discs were tested: (1) hydrophobic without nanostructures (dry/micro) (n = 13); (2) hydrophobic with nanostructures, accelerated aged (dry/nano/AA) (n = 12); (3) hydrophilic without nanostructures (wet/micro) (n = 13); (4) hydrophilic with nanostructures, accelerated aged (wet/nano/AA; SLActive®) (n = 13); (5) hydrophilic with nanostructures, real-time aged (wet/nano/RTA). The animals were sacrificed after four weeks and the biomechanical pull-out force required to remove the discs was evaluated. Adjusted mean pull-out force was greatest for group wet/nano/RTA (64.5 ± 17.7 N) and lowest for group dry/micro (33.8 ± 10.7 N). Multivariate mixed model analysis showed that the pull-out force was significantly greater for all other disc types compared to the dry/micro group. Surface chemistry and topography both had a significant effect on pull-out force (p < 0.0001 for both), but the effect of the interaction between chemistry and topography was not significant (p = 0.1056). The introduction of nanostructures on the TiZr surface significantly increases osseointegration. The introduction of hydrophilicity to the TiZr implant surface significantly increases the capacity for osseointegration, irrespective of the presence or absence of nanotopography.

Synergistic Effect of rhBMP-2 Protein and Nanotextured Titanium Alloy Surface to Improve Osteogenic Implant Properties

One of the major limitations during titanium (Ti) implant osseointegration is the poor cellular interactions at the biointerface. In the present study, the combined effect of recombinant human Bone Morphogenetic Protein-2 (rhBMP-2) and nanopatterned Ti6Al4V fabricated with Directed irradiation synthesis (DIS) is investigated in vitro. This environmentally-friendly plasma uses ions to create self-organized nanostructures on the surfaces. Nanocones (≈36.7 nm in DIS 80°) and thinner nanowalls (≈16.5 nm in DIS 60°) were fabricated depending on DIS incidence angle and observed via scanning electron microscopy. All samples have a similar crystalline structure and wettability, except for sandblasted/acid-etched (SLA) and acid-etched/anodized (Anodized) samples which are more hydrophilic. Biological results revealed that the viability and adhesion properties (vinculin expression and cell spreading) of DIS 80° with BMP-2 were similar to those polished with BMP-2, yet we observed more filopodia on DIS 80° (≈39 filopodia/cell) compared to the other samples (&lt;30 filopodia/cell). BMP-2 increased alkaline phosphatase activity in all samples, tending to be higher in DIS 80°. Moreover, in the mineralization studies, DIS 80° with BMP-2 and Anodized with BMP-2 increased the formation of calcium deposits (&gt;3.3 fold) compared to polished with BMP-2. Hence, this study shows there is a synergistic effect of BMP-2 and DIS surface modification in improving Ti biological properties which could be applied to Ti bone implants to treat bone disease.

Effect of high glucose levels and lipopolysaccharides-induced inflammation on osteoblast mineralization over sandblasted/acid-etched titanium surface.

Poorly controlled diabetes mellitus has been related to higher risk of implant treatment complications due to increased susceptibility to infection and delayed wound healing. Lipopolysaccharides (LPS) stimulate cytokine production leading to chronic inflammation and immunological host response that accentuates the destruction of periodontal tissues. This study aimed to evaluate the effect of different glycemic conditions on secretion and mineralization of bone matrix under sterile inflammation induced by LPS on osteoblasts seeded over sandblasted/acid-etched (SLA) titanium surface. Osteoblast cell viability was performed to determine the influence of different glucose concentrations (5.5, 8, 12, and 24 mM), which were chosen to reflect normal, postprandial, and high glucose values, similar to those typically seen in Diabetes mellitus under clinical conditions. Cells were seeded on titanium SLA discs (Straumann AG, Waldenburg, Switzerland) and exposed to glucose concentrations and LPS (1μg/mL) in order to test inflammatory response (qPCR) and mineralization (Alizarin Red staining). Osteoblast viability was severely decreased when exposed to higher glucose levels (≥12 mM) and LPS (P < .05) compared to control. When the osteoblasts were exposed to LPS and glucose at ≥8 mM, the gene transcripts of inflammatory cytokines were ≈2.5-fold upregulated, while ≤8 mM glucose elicited no significant change compared to control without glucose treatment (P > .05). Osteoblasts exposed to LPS produced sparse extracellular matrix mineralization, especially combined with higher glucose values (≥12 mM), together with decreased calcium deposition compared to control (P < .05). High glucose levels combined with LPS inflammatory stimulation elicited an adverse effect on the volume and quality of mineralized hard tissue formation on SLA titanium surfaces in vitro. Hence, both normal glucose levels and infection control including low levels of circulating LPS during initial osseointegration period may be required to increase the success rate of dental implants.

Experimental implantoplasty outcomes correlate with fibroblast growth in vitro

BackgroundImplantoplasty is an option in peri-implantitis treatment, but little is known about the effect on the soft tissue. The aim of the study was to characterize surface roughness following experimental implantoplasty and to examine its effect on human fibroblast growth and secretion of selected proteins.MethodsTitanium grade IV coins were mechanically treated with six different rotating bur sequences; diamond burs or carbide burs alone, or followed by either Arkansas stone bur or silicone burs. Machined and rough-surface sandblasted, acid-etched (SLA) coins were used as control. The surface topography was characterized by scanning electron microscope and profilometer. Human gingival fibroblasts from two donors were cultured on the coins to quantify the effect on cell morphology, growth, and protein secretion by confocal microscopy and multiplex immunoassay.ResultsAll surface roughness parameters were lower for the surfaces treated with experimental implantoplasty than for the SLA surface, and the sequence of carbide burs followed by silicone burs rendered the least rough surface of the test groups. The implantoplasty procedures changed the elemental composition of the titanium surface. High surface roughness showed a weak to moderate negative correlation to fibroblast growth, but induced a higher secretion of VEGF, IL-6 and MCP-3 to the cell medium compared to the least rough surfaces of the test groups. At day 30 fibronectin levels were higher in the SLA group.ConclusionsThe surface roughness following implantoplasty demonstrated a weak to moderate negative correlation with the growth of fibroblasts. The addition of Arkansas stone and silicon burs to the experimental implantoplasty bur protocol rendered an initial increase in fibroblast growth. Implantoplasty altered the elemental composition of the titanium surface, and had an effect on the fibroblast cytokine secretion and fibronectin levels.

Immobilization of BMP-2, BMP-7 and alendronic acid on titanium surfaces: Adhesion, proliferation and differentiation of bone marrow-derived stem cells.

This study analyzed the influence of titanium (TiO2 ) surface modifications with two osteogenic proteins (BMP-2, BMP-7) and an anti-osteoclastic drug (alendronic acid [AA]) on sandblasted/acid-etched (SLA) and plain TiO2 (PT) on cell adhesion, proliferation and differentiation (alkaline phosphatase [AP] and osteocalcin [OC]) of bone-marrow derived stem cells (BMSCs) after 1, 3 and 7 days in-vitro. Initially, AA surfaces showed the highest cell number and surface coverage. At day 3 and 7, BMP and AA-modified surfaces exhibited a significantly enhanced cell growth. For proliferation, at days 3 and 7, an enhancement on BMP-2, BMP-7 and AA-surfaces was seen. At day 7, SLA also showed a higher proliferation when compared to PT. Initially, AP expression was elevated on SLA and AA surfaces. At days 3 and 7, a significant increased AP expression was seen for SLA, BMP-2, BMP-7 and AA discs. For OC, SLA and AA surfaces had the highest expression after 1 day whereas after 3 and 7 days a significant difference was recorded for SLA, BMP-2, BMP-7 and AA. In conclusion, a beneficial biological effect of a chemical immobilization method of BMP-2, BMP-7 and alendronate onto titanium surfaces on BMSCs was proven.

Positive regulation of Porphyromonas gingivalis lipopolysaccharide-stimulated osteoblast functions by strontium modification of an SLA titanium implant surface.

This study aimed to investigate whether strontium (Sr) ion delivery to the surface of microstructured titanium (Ti) oral implants drives favorable osteoblast functions of mesenchymal stem cells (MSCs) under a Porphyromonas gingivalis lipopolysaccharide (LPS)-stimulated inflammatory condition. The goal is to gain insight for future surface engineering of Ti implants with increased resistance to peri-implantitis and better bone recovery capacity from peri-implant bone destruction. The Sr ions were introduced into a clinically available sandblasted/acid-etched (SLA) Ti implant surface by wet chemical treatment. The results showed that Sr ion incorporation enhances the osteogenesis-related cell functions of bipotent ST2 stem cells in the microstructured SLA type implant surface. Early spreading and osteogenic differentiation (osteogenesis-related mRNA expression, ALP activity and osteocalcin protein secretion) were notably increased in Sr-incorporated SLA implant surface under 1 µg of P. gingivalis LPS stimulation. In addition, Sr ion modification increased early osteogenic differentiation (ALP mRNA expression and ALP activity) of ST2 cells, again under the more severe inflammatory condition induced by a high dose of LPS (10 µg/mL). These results indicate that surface chemistry modification using Sr ions provides microstructured Ti oral implants with greater resistance to the development and progression of inflammatory bone tissue destruction, and increased bone recovery capacity in the bacterial LPS-contaminated Ti oral implant surface by enhancing the early osteogenic differentiation of MSCs.

Human Osteoblast Cell Behaviour on Titanium Discs Treated with Argon Plasma.

(1) Background. Titanium is characterized by its biocompatibility and resistance to stress and fatigue. Treatment with argon plasma may favour growth of human osteoblasts with respect to cell adhesion and proliferation. The aim of this study was to analyse the behaviour of human osteoblasts (MG-63) on Grade IV and V titanium possessing a sand-blasted, acid-etched (SLA) surface. SLA is a widely used surface treatment to create micro- and macroretentions to enhance osteoconductive properties on the surface. (2) Methods. One group of each grade of titanium was decontaminated with argon plasma and compared. On each disc, 20 × 104 cells were cultivated for morphological analysis, study of cell viability (regarding a negative control [100% viability]) and mitochondrial energy balance. (3) Results. At 24 h titanium treated with SLA showed a higher percentage of cell viability (47.3 ± 8.1%) compared to titanium IV treated with argon plasma, which presented a percentage of 79.1 ± 1.1%. Grade V titanium treated with argon plasma presented a higher viability percentage 91.3 ± 3.0% whereas nontreated Grade V titanium presented 53.3 ± 4.0%. Cells cultivated on the surfaces with an argon-plasma treatment were enlarged in comparison to non-treated discs. The cells with smaller circularity with a greater spread and spindle shape were the ones cultivated on the Grade V titanium surface. Cells seeded on treated titanium IV and titanium V, treated or not, showed higher mitochondrial activity over nontreated titanium IV. (4) Conclusions. Cells cultivated on those Grade V titanium discs that were decontaminated with argon plasma presented higher levels of cell adhesion and proliferation, lower mitochondrial damage and a higher mean cell area compared to those not decontaminated with argon plasma.