Search Results (2,024)

The objective of this study was to investigate the physicochemical properties of hybrid coatings with titanium nitride and boron nitride nanoparticles deposited on the TiAlV medical alloy via the sol–gel process. The developed layers were intended to impart bactericidal properties and provide protection against surgical abrasions during the implantation procedure. This study focused on evaluating the microstructure (SEM + EDS), structure (XRD, FTIR), and surface properties, including wettability, surface free energy, and roughness of the synthesized layers. Our results confirmed that it was feasible to produce hybrid layers with various microstructures and diverse layer morphologies. The FTIR and XRD structural analyses confirmed the presence of an organosilicon matrix incorporating the two aforementioned types of ceramic particles. Full article

Background/Objectives: The success of lumbar interbody fusion depends on the implant design and the surgical approach used. This study evaluated the clinical and radiographic outcomes of lateral lumbar interbody fusion (LLIF) and anterior lumbar interbody fusion (ALIF) using a 3D-printed porous titanium interbody cage system. Methods: A retrospective, single-center review of 48 patients treated for degenerative lumbar spine disease was conducted. Patients underwent LLIF, ALIF, or a combination of both using a 3D-printed titanium cage system (J&J MedTech, Raynham, MA, USA). The Oswestry disability index (ODI) and Patient-Reported Outcomes Measurement Information System (PROMIS) metrics were assessed after 6 weeks, 3 months, 6 months, and 12 months. Linear mixed-effects models evaluated the pre- and post-operative differences. Fusion performance and complications were assessed using the Bridwell grading system over 24 months. Results: A total of 78 levels (62 LLIF and 16 ALIF) were analyzed. Fusion rates were 90.3% (56/62) for LLIF levels and 81.3% (13/16) for ALIF levels by the end of 12 months. ODI scores improved significantly after 3 months (MD −13.0, p < 0.001), 6 months (MD −12.3, p < 0.001), and 12 months (MD −14.9, p < 0.001). PROMIS Pain Interference scores improved after 3 months (MD −6.1, p < 0.001), 6 months (MD −3.4, p < 0.001), and 12 months (MD −5.8, p < 0.001). PROMIS Physical Function scores improved after 3 months (MD +3.4, p = 0.032) and 12 months (MD +4.9, p < 0.001). Conclusions: This novel interbody cage demonstrated high fusion rates, significant pain and function improvements, and a favorable safety profile, warranting further comparative studies. Full article

Background: Immediate implant placement in the esthetic zone, particularly in Class II extraction sockets with partial facial bone loss, presents challenges in achieving soft and hard tissue stability. Customized computer-aided design/computer-aided manufacturing (CAD/CAM) titanium abutments may offer advantages over prefabricated stock abutments. This study compared the clinical, radiographic, and patient-reported outcomes of customized CAD/CAM titanium abutments versus stock Laser-Lok stock abutments. Materials and methods: In a single-center, double-blind randomized clinical trial, 48 patients received immediate maxillary anterior implants restored with either customized CAD/CAM titanium abutments (n = 24) or stock titanium abutments (n = 24). Primary outcomes included peri-implant probing depth (PD), mucosal height, Pink Esthetic Score (PES), crestal bone level changes, and patient satisfaction assessed at baseline, 6, and 12 months post-loading. Statistical analysis included effect sizes and 95% confidence intervals. Results: At 12 months, the customized abutment group showed significantly shallower PD (mean difference: −0.54 mm; 95% CI: −0.72 to −0.35; p < 0.001), higher PES (12.21 ± 0.35 vs. 10.41 ± 1.17; p < 0.0001; Cohen’s d = 2.08), and less crestal bone loss (1.75 ± 0.36 mm vs. 2.33 ± 0.52 mm; p < 0.0001). Patient satisfaction scores were also higher in the customized group (p = 0.003). Within-group improvements were observed in both groups over time. No implant failures occurred. Conclusions: At 1-year follow-up, customized CAD/CAM titanium abutments demonstrated improved peri-implant soft tissue parameters, esthetics, and patient satisfaction compared to stock abutments. While these findings support their use in esthetically demanding immediate implant cases, the short-term duration and single-center design warrant further long-term multicenter studies to confirm durability. Trial registration: Registered at ClinicalTrials.gov on 19/01/2025 (NCT06791655). Full article

The different macro and micro geometries of dental implants are parameters that directly affect osseointegration, making them an important area for research. The objective of this preclinical study was to compare, through histological and histomorphometric analyses, the biological response of two different dental implant surfaces in osseointegration. Surface morphology and chemistry were characterized by SEM/EDX, optical-emission spectroscopy, protein adsorption (BSA), and adipose-derived stem-cell morphology. For the in vivo arm, ten commercially pure titanium implants (n = 5 LS160 + 5 SBAE) were placed bilaterally in the tibiae of five skeletally mature New Zealand rabbits (one implant of each surface per animal). After six weeks, undecalcified sections were prepared and bone-to-implant contact (BIC) and bone-area-fraction occupancy (BAFO) were quantified histomorphometrically. Data normality was confirmed with the Shapiro–Wilk test; paired two-tailed Student’s t-tests were applied (α = 0.05). Results: The descriptive histological analysis showed a fraction of pre-existing bone in all experimental groups, which probably ensured primary stability. Adjacent to this area, it was possible to observe peri-implant newformed bone in all tested groups. The results of the histomorphometric analysis of BIC and BAFO were considered normal by the Shapiro–Wilk test (p > 0.05); after six weeks of implantation, the BIC values for the LS160 and SBAE groups were 44.13 (15.83–72.43) and 39.24 (10.72–89.21), respectively. The analysis of variance (ANOVA and Tukey’s post-test) showed no statistical differences between the groups tested. Likewise, the bone volume density showed no statistical differences between the groups (ANOVA and Tukey’s post-test) with averages of 41.27 (C.I. 24.00–58.55) and 26.52 (C.I. −17.51–70.54) in the LS160 and SBAE groups, respectively. Although both surfaces showed similar osseointegration after six weeks, the new surface appears to be a promising, eco-friendly alternative to SBAE. Future studies with shorter time points and larger samples are needed to assess early biological responses. Full article

Titanium and its alloys are widely used in orthopedics because of their excellent mechanical properties and biocompatibility; however, their bioinert surface results in sluggish osseointegration and renders implants susceptible to bacterial infection. This study innovatively constructed a “CHP-Ti-MAO” composite coating, which aims to simultaneously improve early osseointegration and antibacterial performance. CHP micron coatings coated with hydroxyapatite (HA) and curcumin (Cur) at different PLGA concentrations (50%, 100%, and 150%) were deposited on the basis of calcium–phosphorus ceramic coatings prepared by micro-arc oxidation (MAO) following the emulsification-solvent volatilization method. It was found that increasing the concentration of PLGA can increase the particle size of the coating, enhance the hydrophilicity, and significantly improve the sustained release performance of the drug. Among them, the 100% PLGA concentration group performed the best: the drug-release half-life reached 75 h, and the corrosion current density was the lowest (9.5 × 10⁻⁹ A/cm²), showing the best corrosion resistance. This group of coatings has a strong and long-term antibacterial effect on Escherichia coli, with an antibacterial rate of more than 95% at 24 h and more than 99% by day 17. The hemolysis rate of all coatings was lower than 5%, indicating good biocompatibility. This study confirmed that 100% CHP-Ti-MAO composite coating successfully solved the limitations of excessive pore size and insufficient antibacterial persistence of an MAO layer and also had excellent slow-release, corrosion resistance, and high-efficiency antibacterial capabilities, which provided an important basis for the development of a new generation of multifunctional titanium-based implants. Full article

The biocompatibility of orthodontic archwires is crucial for ensuring patient safety and the long-term success of orthodontic treatment. This study evaluated the biocompatibility of stainless steel (SS) and nickel–titanium (Ni-Ti) orthodontic archwires, as well as stainless steel metal brackets, before and after the application of a graphene coating. The assessment was based on the materials’ effects on a fibroblast cell line and on the development of a foetal chicken egg embryo. Fibroblasts that had been in temporary contact with steel and NiTi archwires after CW-CVD (cold wall chemical vapour deposition) treatment exhibited changes in morphology in the presence of the material. The materials exhibited moderate cytotoxicity. For metal brackets, the treated samples caused stronger cytotoxic changes in the culture. Unlike graphene-coated implants, where cells were found to directly adhere to the surface, the embryonic tissues did not treat the non-graphene-coated implants as an adhesive material. This study suggests that depositing carbon-based coatings, including graphene, on stainless steel archwires may reduce the cytotoxicity of orthodontic components. Using graphene increases adhesion of the implant surface to membrane-derived cells and the embryonic yolk and does not inhibit the further development of the chicken egg embryo. Full article

This study investigates a novel approach based on micro-pulse plasma electrolytic oxidation (μPPEO), aiming to improve the control over key parameters such as the Ca/P ratio, the formation of anatase and rutile phases, and the porosity of titanium surfaces—factors that are critical for enhancing bioactivity. By employing electrical micro-pulses with widths of 50 μs or 100 μs, our aim was to restrict the discharge time and subsequent surface/electrolyte reactions. The results demonstrate that μPPEO-treated surfaces exhibit uniform pore diameters, a Ca/P ratio of approximately 1.67, and the better control of anatase/rutile formation. The μPPEO treatment successfully produced hydrophilic surfaces, with the 6Ti50 sample displaying the highest polar component of surface energy. Notably, this sample was the only one to support cell viability comparable to that of the polystyrene surface on the 24-well plate, emphasizing its strong potential for clinical applications. Across all treated surfaces, OFCOL osteoblasts displayed a spindle-like morphology with elongated filopodia, suggesting favorable cell interactions and adaptability to the treated surfaces. This study underscores the promise of PPEO as a valuable technique for biomedical applications, particularly in controlling and optimizing dental implant surfaces. Full article

Total ankle arthroplasty (TAA) has evolved significantly through advances in alloy selection and manufacturing technologies. This narrative review examines the metallurgical foundations of contemporary TAA implants, analyzing primary alloy systems and their mechanical properties. Cobalt-chromium alloys provide superior mechanical strength and durability but present metal ion release concerns, while titanium alloys (Ti6Al4V) optimize biocompatibility with elastic modulus values (101–113 GPa) closer to bone, despite tribological limitations. Novel β-titanium formulations (Ti-35Nb-7Zr-5Ta, Ti10Mo6Zr4Sn3Nb) eliminate toxic aluminum and vanadium components while achieving lower elastic modulus values (50–85 GPa) that better match cortical bone properties. Manufacturing has transitioned from traditional methods (investment casting, forging, CNC machining) toward additive manufacturing technologies. Selective laser melting and electron beam melting enable patient-specific geometries, controlled porosity, and optimized microstructures, though challenges remain with residual stresses, surface finish requirements, and post-processing needs. Emerging biodegradable materials, composite structures, and hybrid implant designs represent promising future directions for addressing current material limitations. This review provides evidence-based insights for alloy selection and manufacturing approaches, emphasizing the critical role of materials engineering in TAA implant performance and clinical outcomes. Full article

Background/Objectives: Anterior cervical discectomy and fusion (ACDF) is a common procedure for treating cervical spondylotic myelopathy. Limited research exists on the predictors of subsidence following ACDF. Subsidence can compromise surgical outcomes, alter alignment, and predispose patients to further complications, making it essential to prevent and understand it. This study aims to identify key risk factors for clinically significant subsidence and evaluate its impact on cervical alignment parameters in a large, diverse patient population. Methods: We conducted a retrospective review of patients who underwent ACDF between 2013 and 2022 at a single institution. Subsidence was calculated as the mean change in anterior and posterior disc height, with clinically significant subsidence being defined as three millimeters or more. Univariate analysis was followed by regression modeling to identify subsidence predictors and analyze patterns. Subgroup analyses stratified patients by implant type, number of levels fused, and cage material. Results: A total of 96 patients with 141 levels of ACDF met the inclusion criteria. Patients with significant subsidence were younger on average (52.44 vs. 55.94 years; p = 0.074). Those with less postoperative lordosis were more likely to experience significant subsidence (79.5% vs. 90.2%; p = 0.088). Patients with significant subsidence were more likely to have standalone implants (38.5% vs. 16.7%; p < 0.01), taller cages (6.62 mm vs. 6.18 mm; p < 0.05), and greater loss of segmental lordosis (7.33 degrees vs. 3.31 degrees; p < 0.01). Multivariate analysis confirmed that standalone implants were a significant independent predictor of subsidence (OR 2.679; p < 0.05), and greater subsidence was positively associated with loss of segmental lordosis (OR 1.089; p < 0.01). Subgroup analysis revealed that multi-level procedures had a higher incidence of subsidence (35.7% vs. 28.1%; p = 0.156), and PEEK cages demonstrated similar subsidence rates compared to titanium constructs (28.1% vs. 29.4%; p = 0.897). Conclusions: Standalone implants are the strongest independent predictor of significant subsidence, and those that experience subsidence also show greater loss of segmental lordosis, although not overall lordosis. These findings have implications for surgical planning, particularly in patients with borderline bone quality or requiring multi-level fusions. The results support the use of plated constructs in high-risk patients and emphasize the importance of individualized surgical planning based on patient-specific factors. Further research is needed to explore these findings and determine how they can be applied to improve ACDF outcomes. Full article

Background: The long-term success of total knee arthroplasty (TKA) is often compromised by stress shielding, which can lead to bone resorption and even implant loosening. This study employs finite element analysis (FEA) to compare the stress-shielding effects of a knee prosthesis made from polyether ether ketone (PEEK) with a traditional titanium Ti6Al4V implant on an osteoporotic tibial bone model. Methods: Stress distribution and the stress-shielding factor (SSF) were evaluated at seven critical points in the proximal tibia under physiological loading conditions. Results: Results indicate that the PEEK prosthesis yields a more uniform stress transmission, with von Mises stress levels within the optimal 2–3 MPa range for bone maintenance and consistently negative or near-zero SSF values, implying minimal stress shielding. Conversely, titanium implants exhibited significant stress shielding with high positive SSF values across all points. Additionally, stress concentrations on the polyethylene liner were lower and more evenly distributed in the PEEK model, suggesting reduced wear potential. Conclusions: These findings highlight the biomechanical advantages of PEEK in reducing stress shielding and preserving bone integrity, supporting its potential use to improve implant longevity in TKA. Further experimental and clinical validation are warranted. Full article

Titanium–aluminum–vanadium (Ti6Al4V) is a material chosen for spine, orthopedic, and dental implants due to its combination of desirable mechanical and biological properties. Lasers have been used to modify metal surfaces, enabling the generation of a surface on Ti6Al4V with distinct micro- and nano-scale structures. Studies indicate that topography with micro/nano features of osteoclast resorption pits causes bone marrow stromal cells (MSCs) and osteoprogenitor cells to favor differentiation into an osteoblastic phenotype. This study examined whether the biological response of human MSCs to Ti6Al4V surfaces is sensitive to laser treatment-controlled micro/nano-topography. First, 15 mm diameter Ti6Al4V discs (Spine Wave Inc., Shelton, CT, USA) were either machined (M) or additively manufactured (AM). Surface treatments included no laser treatment (NT), nanosecond laser (Ns), femtosecond laser (Fs), or nanosecond followed by femtosecond laser (Ns+Fs). Surface wettability, roughness, and surface chemistry were determined using sessile drop contact angle, laser confocal microscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Human MSCs were cultured in growth media on tissue culture polystyrene (TCPS) or test surfaces. On day 7, the levels of osteocalcin (OCN), osteopontin (OPN), osteoprotegerin (OPG), and vascular endothelial growth factor 165 (VEGF) in the conditioned media were measured. M NT, Fs, and Ns+Fs surfaces were hydrophilic; Ns was hydrophobic. AM NT and Fs surfaces were hydrophilic; AM Ns and Ns+Fs were hydrophobic. Roughness (Sa and Sz) increased after Ns and Ns+Fs treatment for both M and AM disks. All surfaces primarily consisted of oxygen, titanium, and carbon; Fs had increased levels of aluminum for both M and AM. SEM images showed that M NT discs had a smooth surface, whereas AM surfaces appeared rough at a higher magnification. Fs surfaces had a similar morphology to their respective NT disc at low magnification, but higher magnification revealed nano-scale bumps not seen on NT surfaces. AM Fs surfaces also had regular interval ridges that were not seen on non-femto laser-ablated surfaces. Surface roughness was increased on M and AM Ns and Ns+Fs disks compared to NT and Fs disks. OCN was enhanced, and DNA was reduced on Ns and Ns+Fs, with no difference between them. OPN, OPG, and VEGF levels for laser-treated M surfaces were unchanged compared to NT, apart from an increase in OPG on Fs. MSCs grown on AM Ns and Ns+Fs surfaces had increased levels of OCN per DNA. These results indicate that MSCs cultured on AM Ns and AM Ns+Fs surfaces, which exhibited unique roughness at the microscale and nanoscale, had enhanced differentiation to an osteoblastic phenotype. The laser treatments of the surface mediated this enhancement of MSC differentiation and warrant further clinical investigation. Full article

This narrative review explores the role of additive manufacturing (AM) technologies in the production of dental implants, focusing on materials and key AM methods. The study discusses several materials used in implant fabrication, including porous titanium, trabecular tantalum, zirconium dioxide, polymers, and composite materials. These materials are evaluated for their mechanical properties, biocompatibility, and suitability for AM processes. Additionally, the review examines the main AM technologies used in dental implant production, such as selective laser melting (SLM), electron beam melting (EBM), stereolithography (SLA), selective laser sintering (SLS), and direct metal laser sintering (DMLS). These technologies are compared based on their accuracy, material limitations, customization potential, and applicability in dental practice. The final section presents a data source analysis of the Web of Science and Scopus databases, based on keyword searches. The analysis evaluates the research trends using three criteria: publication category, document type, and year of publication. This provides an insight into the evolution and current trends in the field of additive manufacturing for dental implants. The findings highlight the growing importance of AM technologies in producing customized and efficient dental implants. Full article

Titanium alloys such as Ti-6Al-4V are widely used in biomedical implants due to their excellent mechanical properties and biocompatibility, but their bioinert nature limits osseointegration and antibacterial performance. This study proposes a multifunctional surface coating system integrating a thermally oxidized TiO₂ interlayer with a hydroxyapatite (HAp) top layer synthesized via a green route using Hylocereus undatus extract. The HAp was deposited by electrophoretic deposition (EPD), enabling continuous coverage and strong adhesion to the pre-treated Ti-6Al-4V substrate. Structural, morphological, chemical, and electrical characterizations were performed using XRD, SEM, EDS, Raman spectroscopy, and impedance spectroscopy. Bioactivity was assessed through apatite formation in simulated body fluid (SBF), while antibacterial properties were evaluated against Staphylococcus aureus. The results demonstrated successful formation of crystalline TiO₂ (rutile phase) and calcium-rich HAp with good surface coverage. The HAp-coated surfaces exhibited significantly enhanced bioactivity and strong antibacterial performance, likely due to the combined effects of surface roughness and the bioactive compounds present in the plant extract. This study highlights the potential of eco-friendly, bio-inspired surface engineering to improve the biological performance of titanium-based implants. Full article

Background/Objectives: Tamoxifen, a selective estrogen receptor modulator widely used as an adjunct in the treatment of breast cancer, has known effects on bone metabolism, although its impact on osseointegration and cellular responses during early bone healing remains unclear. Understanding these effects is essential given the increasing use of dental implants in cancer survivors. The study aimed to observe the influence of tamoxifen on human osteosarcoma (SAOS-2) cells lines, as well on the osseointegration of titanium implants in ovariectomized female rats. Methods: SAOS-2 cells were incubated with Dulbecco’s modified growth medium. Six titanium (Ti) disks were used at each time point. The samples were divided into groups with the presence (TAM, n = 36) or not (CTR, n = 36) of tamoxifen in a concentration of 2 μM. In vivo, 72 animals were divided in groups with bilateral ovariectomy or SHAM and tamoxifen administration or not (15 mg/kg). Cell viability, mineralization rate, and collagen synthesis were assessed, as well as bone/implant contact (BIC) and bone ingrowth (BIN). Results: Tamoxifen caused a decrease in SAOS-2 viability, although an increase in the mineralization rate was observed. In vivo, the TAM groups presented higher BIC and BIN when compared to their control, but a lower percentage of mature collagen cells. Conclusions: Based on our findings, in vitro, the therapy with TAM slightly reduced the viability of SAOS-2 cells while significantly increasing the mineralization rate. In vivo, the therapy positively influenced BIC and BIN during the osseointegration phase. Full article

The thermo-chemical treatment of dental implants leads to the formation of sodium titanate crystals on their surface. When in contact with blood, these crystals dissolve and trigger an ionic exchange cascade, resulting in the formation of a calcium apatite layer. This study, carried out both in vitro and in an animal model, aimed to determine whether the cooling rate of the treatment affects the size of the deposited crystals, and whether this in turn influences wettability and early bone-to-implant contact (BIC). A total of 50 dental implants and 50 titanium discs were treated using four different cooling rates, along with a control group. Crystal size was analyzed on implant surfaces using scanning electron microscopy, and wettability was assessed on titanium discs using a goniometer. Finally, the implants were placed in the tibiae of 13 rabbits, and histological analysis was performed after three weeks to compare BIC among groups. Results suggest that a cooling rate of 75 °C/h produces smaller sodium titanate crystals, which are associated with significantly improved surface wettability and a higher percentage of bone-to-implant contact after 3 weeks of healing (p < 0.05). Full article