Search Results (788)

This study explores the influence of precursor nature on the structural and mechanical characteristics of hydroxyapatite–yttria partially stabilized zirconia (HAp–YSZ) nanocomposites designed for biomedical applications. Precursor powders for obtaining these ceramic composites were synthesized via wet coprecipitation, using different calcium phosphate precursors: dibasic and monobasic ammonium phosphates for hydroxyapatite, and zirconyl chloride with yttrium acetate for YSZ. The dried precipitated powders were thermally treated at 600 °C and 800 °C and characterized by X-ray diffraction (XRD), thermal analysis (DTA–TG), transmission electron microscopy (TEM), and BET surface area measurements. The nanocomposites containing 70–90 wt.% HAp and 10–30 wt.% YSZ were sintered between 1000 °C and 1400 °C. Microstructural and physical properties were evaluated using scanning electron microscopy (SEM), open porosity, and compressive strength testing. Results revealed that precursor type and calcination temperature strongly affected crystallinity, particle size, and phase composition, influencing both porosity and mechanical strength of the final materials. An optimal sintering temperature of approximately 1200 °C was identified, balancing densification and phase stability. The findings demonstrate that controlling precursor chemistry and heat treatment enables fine-tuning of nanocomposite structure and performance, supporting their potential as bioactive, mechanically enhanced ceramics for orthopedic implant applications. Full article

Background and Objectives: There is a lack of comprehensive, focused reviews on the topic of open bite in the literature. This study aims to quantitatively reveal publication productivity, annual trends, publication sources, key themes, and citation patterns in the field of open bite. Materials and Methods: A total of 1208 articles and reviews published between 1973 and 2025, obtained from the Web of Science database, were analyzed using bibliometric and network analysis methods. Results: A significant increase in the number of publications after 2010, acceleration particularly after 2015, and high productivity observed in the 2018–2024 period. A clear increasing trend was observed over time. 71.5% of publications are included in SCI-Expanded. Journal distribution is centralized, with the American Journal of Orthodontics and Dentofacial Orthopedics and Angle Orthodontist being the dominant publications. Keyword and cluster analyses showed that the literature is concentrated on four main thematic axes: (1) etiology and biomechanical processes, (2) surgical approaches and orthognathic interventions, (3) early intervention and habit control, (4) post-treatment stability and relapse. Furthermore, treatment-oriented concepts such as “miniscrew/temporary anchorage device,” “molar intrusion,” and “cephalometric analysis” are central. Conclusions: The study reveals that open bite has become an increasingly prevalent and thematically diverse area of research in the orthodontic literature. The current distribution indicates that research focuses on both clinical application and treatment outcomes; however, it also highlights the importance of long-term comparative data and studies on treatment stability. In the future, methodological standardization and comparable long-term data will contribute to the maturation of the literature. Full article

Background and Objectives: Access to anterior cruciate ligament reconstruction (ACLR) varies substantially across health systems, yet national-level data from Eastern Europe remain limited. This study provides the first nationwide, regionally stratified assessment of ACLR activity in Romania, examining geographic variation, socioeconomic and workforce determinants, and inequality. Materials and Methods: We conducted a retrospective cross-sectional analysis of all ACLRs reported in the national administrative hospital database (2017–2023), supplemented with demographic, GDP, and workforce statistics. Outomes included incidence per 100,000 population, private-sector share, and sex distribution. Regional differences were tested using Kruskal–Wallis and Dunn post hoc comparisons. Predictors of ACLR incidence and private-sector utilization were identified through multivariable Poisson and logistic models. Inequality metrics (Gini coefficients, P90/P10 ratios) and sensitivity analyses excluding Bucharest–Ilfov were also performed. Results: A total of 11, 080 ACLRs were recorded. Incidence varied markedly across regions, from a median of 40.0 per 100,000 in Bucharest–Ilfov to <1–3 per 100,000 in the South, South-East, and South-West (p < 0.001). Higher GDP per capita correlated with incidence (ρ = 0.36) and explained 45% of its variance. Private-sector involvement ranged from <5% in Bucharest–Ilfov and the South to 80–100% in the Centre, North-West, and South-East. In adjusted Poisson models, GDP, surgeon availability, and private-sector share were strong independent predictors of incidence (all p < 0.001). Private-sector access was primarily determined by the proportion of private orthopedic surgeons (OR 21.03). National inequality was extreme (Gini 0.842–0.752; P90/P10 > 10⁹), reflecting the concentration of procedures within a small number of counties. Results were consistent across sensitivity analyses. Conclusions: ACLR in Romania displays severe territorial inequities driven by socioeconomic development, workforce distribution, and uneven private-sector capacity. Targeted regional investment and coordinated workforce strategies are necessary to improve equitable access to surgical care. Full article

Background and Objectives: Coronal plane deformities of the knee, particularly genu valgum and varum, represent common indications for guided growth in pediatric orthopedics. This study evaluates the clinical and radiographic outcomes of temporary hemiepiphysiodesis using tension-band plates in skeletally immature patients and identifies factors associated with successful correction. Materials and Methods: A retrospective review was conducted on patients treated with tension-band plate hemiepiphysiodesis for knee valgus or varus deformities between 2012 and 2023. Inclusion required open physes, pre- and postoperative full-length radiographs, and follow-up until implant removal or skeletal maturity. Mechanical axis parameters (mLDFA, mMPTA) were compared pre- and postoperatively, and correction rates were calculated. Idiopathic cases were analyzed separately from those with neurological or osteological disorders. Results: Sixty-six limbs were included (51 valgus, 15 varus). In the idiopathic subgroup, significant correction was achieved, with mLDFA improving by +5.19° and mMPTA by −1.88°, corresponding to annual correction rates of 4.75°/year and −1.74°/year, respectively (p < 0.001). Regression analysis showed no significant predictive value of age or treatment duration for total correction. Patients with pathological physes demonstrated inconsistent outcomes, often requiring additional procedures. No major complications occurred. Conclusions: Temporary hemiepiphysiodesis using tension-band plates is a safe, minimally invasive, and highly effective method for correcting idiopathic valgus deformities in growing children, with correction rates comparable to the existing literature. Outcomes in patients with neurological or osteological comorbidities remain less predictable, underscoring the need for individualized planning and close follow-up. Full article

Osteoarthritis (OA) is a progressive degenerative joint disease that fundamentally alters the mechanical environment of the knee. This study utilizes a finite element framework to evaluate the biomechanical response of the distal femur in healthy and osteoarthritic conditions across critical functional postures. To isolate the bone’s inherent structural stiffness and avoid numerical artifacts, a free-body computational approach was implemented, omitting external surface fixations. The distal femur was modeled as a linearly elastic domain with material properties representing healthy tissue and OA-induced degradation. Simulations were performed under passive gravitational loading at knee flexion angles of $0^{\circ },{60}^{\circ },$ and ${90}^{\circ }$. The results demonstrate that the mechanical response is highly sensitive to postural orientation, with peak von Mises stress consistently occurring at ${60}^{\circ }$ of flexion for both models. Quantitative analysis revealed that the stiffer Normal bone attracted significantly higher internal stress, with a reduction of over 30% in peak stress magnitude observed in the OA model at the most critical flexion angle. Total displacement magnitudes remained relatively stable across conditions, suggesting that OA-induced material softening primarily influences internal stress redistribution rather than global structural sag under passive loads. These findings provide a quantitative index of skeletal vulnerability, supporting the development of patient-specific orthopedic treatments and rehabilitation strategies. Full article

We demonstrate the enhancement of antibacterial and cytocompatibility characteristics of femtosecond laser-treated pure titanium and Ti-6Al-4V titanium alloy samples suitable for orthopedic implant applications. We controlled the wettability of the titanium samples by tailoring the surface geometry using a femtosecond laser. To increase the hydrophobicity, laser-assisted micro-grids patterning was performed on the titanium samples, where we achieved a highest contact angle of 144.6° for a 1 µL de-ionized water droplet. In contrast, the hydrophobic Ti-6Al-4V titanium alloy surfaces were converted to hydrophilic surfaces by fabricating periodic micro-gratings on the samples’ surface, where a lowest contact angle of 19.84° was achieved. Furthermore, we assessed the biocompatibility of the micro-patterned titanium samples by investigating the antibacterial activity against Staphylococcus Aureus bacteria. Moreover, the cytocompatibility of the micro-patterned titanium samples was examined using NCTC Clone 929 (L-929) mouse fibroblasts. The laser-treated titanium samples exhibited enhanced antibacterial performance while maintaining excellent cell compatibility. The experimental results confirmed excellent correlation with the wettability of the laser-patterned samples and their antibacterial characteristics and cytocompatibility. Overall, the findings highlight femtosecond laser surface structuring as a highly effective strategy to simultaneously improve antibacterial behavior and the biocompatibility of implant materials, offering a promising way for the advanced functionalization of orthopedic implants. Full article

Contemporary advances in bioengineering and materials science have substantially improved the viability of medical implants. The demand for optimized implant technologies has led to the development of advanced coatings that enhance biocompatibility, antimicrobial activity, and durability. Implant manufacturers and surgeons must anticipate both biological and mechanical challenges when implementing devices for patient use. Key areas of concern include infection, corrosion, wear, immune response, and implant rejection; regulatory and economic considerations must also be addressed. Materials science developments are optimizing the integration of established materials such as biometrics, composites, and nanomaterials, while also advancing fabrication-based innovations including plasma functionalization, anodization, and self-assembled monolayers. Emerging smart and stimuli-responsive surface technologies enable controlled drug delivery and real-time implant status communication. These innovations enhance osseointegration, antimicrobial performance, and overall device functionality across orthopedic, dental, and cardiovascular applications. As implant design continues to shift toward personalized, responsive systems, advanced coating technologies are poised to deliver significantly improved long-term clinical outcomes for patients. Full article

Zinc and its alloys have been regarded as an alternative option for biodegradable implant materials to magnesium and iron-based alloys due to their promising degradation rate. However, poor osseointegration with bone tissue limits their further clinical application. Considering the biofunction of strontium (Sr), namely promoting the formation of bone tissue, in this work, a ZnO-Sr composite coating was prepared on pure Zn via anodic oxidation to boost bioactivity. Surface morphology and composition of the layer were examined via scanning electron microscopy (SEM) and X-ray diffraction (XRD). Electrochemical measurements were carried out to assess the corrosion behaviour. Long-term immersion tests in simulated body fluid (SBF) for up to 21 days were conducted to evaluate the in vitro bioactivity. Corrosion morphology and corrosion products were studied to reveal the corrosion mechanism. The results demonstrated that the Sr-ZnO coating optimized the corrosion rate and enhanced the bioactivity of the substrate, improving its potential for orthopedic applications. Full article

Introduction: Medial compartment knee osteoarthritis (OA) is characterized by varus deformity. A medial open-wedge high tibial osteotomy (MOWHTO), frequently invoked in the treatment of this deformity, affects the knee as well as the ankle joints. This study aims to evaluate the radiological and clinical effects of a MOWHTO on the ankle joint. Materials and Methods: A retrospective analysis was conducted with data from 110 patients (mean age: 52 years; 74.5% female) who underwent a MOWHTO between 2020 and 2023. Radiographic assessments were conducted both preoperatively and one year after surgery using full-length weight-bearing radiographs. The measurements included several alignment parameters such as the hip–knee–ankle angle (HKA), medial proximal tibial angle (MPTA), joint line convergence angle (JLCA), lateral distal tibial angle (LDTA), and talar tilt. Clinical outcomes were assessed using the Lysholm knee score and the American Orthopedic Foot and Ankle Society (AOFAS) ankle score. Results: While changes in the LDTA demonstrated a small effect size (d = 0.225), moderate-to-large effect sizes were observed in key alignment parameters (MPTA (d = 0.838), the JLCA (d = 0.798), and talar tilt (d = 0.752)), all of which showed statistically significant differences indicative of a correction in the joint alignment of potential clinical significance. Median Lysholm and AOFAS scores at one year were 90 and 100, respectively, indicating favorable clinical outcomes. No significant difference in outcomes was observed based on the amount of correction. Conclusions: An MOWHTO not only restores knee alignment but also significantly improves ankle alignment in the coronal plane. These findings suggest that an MOWHTO is associated with the restoration of knee alignment and with improvements in ankle alignment in the coronal plane. Full article

Polymethylmethacrylate (PMMA) bone cement is widely used in orthopedics, accounting for approximately 80% of knee joint replacements in the United States. While prosthesis designs and materials have evolved to improve performance and durability, PMMA cement has undergone minimal compositional changes. Carbon-based nanomaterials, particularly graphene oxide (GO), have attracted interest for their ability to enhance the mechanical and thermal properties of orthopedic cements. This study evaluated the effects of incorporating different GO concentrations into PMMA bone cement on its mechanical properties, cytocompatibility, and antibacterial activity. PMMA was modified with GO at 0.1, 0.25, and 0.5 weight percent (wt%) for mechanical and antibacterial tests, and at 1.0 wt% for cytocompatibility. Mechanical performance was assessed via four-point bending tests. Cytocompatibility was evaluated using mouse embryonic fibroblasts (NIH/3T3), and antibacterial activity was tested against Staphylococcus aureus using a modified direct contact assay. GO incorporation significantly increased Young’s modulus (0.1% and 0.25%, p = 0.009) and improved tensile strength (p = 0.0015) and flexural strength (p = 0.025) at 0.1%. Cytocompatibility remained comparable to the control (p = 0.873). Antibacterial activity was concentration dependent, with 0.25% and 0.5% GO maintaining significant bacterial inhibition up to 48 h, whereas 0.1% showed no sustained effect. Overall, 0.25 wt% GO provided the most suitable balance between mechanical integrity and antibacterial performance, indicating that PMMA–GO bone cements with this composition can combine enhanced mechanical properties with relevant antibacterial activity without compromising biocompatibility, and are therefore promising candidates for orthopedic applications. Full article

This study aimed to develop a sustainable route for processing biogenic calcium carbonate from Perna perna mussel shell waste and converting it into hydroxyapatite (HA), as well as to evaluate its potential for bone and dental tissue engineering applications. Mussel shells were decarbonized (400 °C), milled, and converted to HA via wet chemical precipitation using a nominal Ca/P molar ratio of 1.67 during synthesis followed by thermal treatment (900 °C). Comprehensive characterization included SEM, FTIR, XRD, Raman spectroscopy, XRF, TGA, and BET analysis. Biological evaluation involved cytotoxicity assays (MTT), antimicrobial testing, and odontogenic differentiation studies (Alizarin Red) using SHEDs. Statistical analysis by one-way ANOVA and Tukey post hoc tests (α = 0.05). SEM revealed a microstructured morphology composed of agglomerates, favorable for biomedical applications. FTIR and XRD confirmed the conversion of CaCO₃ to hydroxyapatite, while thermal analysis demonstrated the material’s stability. The HA exhibited secondary minor phase (13%) β-TCP form of calcium phosphate (Ca_2.997H_0.006(PO₄)₂), high crystallinity (about 80%), and nanoscale crystallite size (85 nm, 2.5–5.0 m²/g), despite forming larger agglomerates in suspension. The material showed favorable physicochemical properties (neutral pH, −18.5 mV zeta potential), but no inhibition was detected in antimicrobial testing. In vitro assays showed excellent cytocompatibility (viability > 70% at 12.5 µg/mL) and significant osteogenic potential (high mineralization vs. controls, p < 0.05). Mussel shell-derived HA presents a sustainable, clinically relevant biomaterial with ideal properties for bone regeneration. The study establishes a complete waste-to-biomaterial pipeline while addressing key requirements for dental and orthopedic applications. Full article

Background and Objectives: There are many well-described approaches to symptomatic ventral hernia management; however, there remains a significant patient population with limited options for a durable ventral hernia repair with a reasonable risk of infection and recurrence. Drawing from the orthopedic literature, we changed our approach to this clinical problem and developed a palliative ventral hernioplasty pathway. Materials and Methods: A retrospective review (2017–2019) of patients’ palliative ventral hernioplasty was performed. Results: In total, 43 patients included, with a female preponderance of 24 (58.6%) and a mean age 61.5 ± 11.5 years. The mean BMI was 38.1 kg/m² (IQR: 25.4–62), and 28 patients (65.1%) had a history of prior wound/mesh infection. Urgent repair was performed in 14 patients. Overall polypropylene prosthetic was implanted in 26 patients, and bioprosthetic/absorbable mesh was used in the remaining. The mean surface area of the implanted mesh was 561 cm². The most common wound complications identified were skin separation (30.2%) and seroma formation (48.8%). Hernia recurrence occurred in four (9.3%) patients, with a mean follow-up of 24.1 months (9–37). Three patients had central lightweight mesh rupture and one had a recurrence (bioprosthetic mesh); all were subsequently repaired. Conclusions: Despite the small number of patients, our palliative ventral hernia repair pathway offers durable repair with an acceptable risk of recurrence and mesh infection in patients who would otherwise be considered nonoperative. Full article

Mg-Zn alloys are a promising type of biodegradable material for orthopedic devices, combining the natural advantages of Mg with the properties provided by Zn. This study examines how temperature affects the behavior of three MgxZn alloys (x = 1.4: 6.1 and 7.8) obtained by induction levitation. Normal temperatures of 20–25 °C and 40 °C simulating fever conditions were selected. Microstructural characterization and microhardness tests were conducted to characterize the alloys. Corrosion behavior was analyzed by open circuit potential, linear polarization, and electrochemical impedance spectroscopy. The balance between matrix softening and intermetallic formation becomes more sensitive when the alloys are exposed to elevated temperatures when microstructural heterogeneities become more influential. Although higher Zn content can facilitate the formation of more stable Zn-rich films, excessive Zn content, as in the 7.8%Zn alloy, also promotes micro-galvanic corrosion through increased MgZn intermetallic phase content, meaning that temperature amplifies both the beneficial and detrimental effects of Zn. Full article

Tissue regeneration is essential for wound healing, organ function restoration, and overall patient recovery. Its success significantly impacts medical procedures in fields like internal medicine and orthopedics, enhancing patient quality of life. Recent advances in regenerative medicine, particularly the combination of advanced drug delivery systems (DDS) and bioengineering, have enabled customized methods to improve tissue regeneration outcomes. However, conventional tissue engineering techniques have drawbacks, often using static scaffolds that lack the dynamic properties of real tissues, leading to subpar healing outcomes. The use of 3D printing and other advanced scaffolding techniques allows for the creation of bio functional scaffolds that deliver bioactive molecules at precise locations and times. The optimal integration of biological systems with enhanced material properties for personalized treatment options remains unclear. There is a need for more research into the complex interactions between cellular biology, drug delivery, and material technology to improve tissue regeneration. Despite progress in developing bioactive scaffolds and localized drug delivery methods, the interactions among different scaffold materials, bioactive agents, and cellular behaviors within the regenerative ecosystem are not fully understood. While there is extensive research on 3D-printed scaffolds in tissue engineering, there is a lack of studies integrating bio printing with in vivo biological reactions in real time. Limited research on the dynamic integration of patient-specific parameters in regeneration methods highlights the need for customized approaches that consider individual physiological differences and the complex biological environment at injury sites. Additionally, challenges arise when translating laboratory results into effective therapeutic applications, underscoring the necessity for interdisciplinary collaboration and innovative design approaches that align advanced material properties with biological needs. Full article

Purpose: The purpose of this study was to investigate how the choice of axial CT level affects the reliability and diagnostic accuracy of the Dejour classification for trochlear dysplasia and to evaluate a novel level defined at the most superior extent of the Blumensaat line. Materials and methods: Patients who presented with patellar instability or acute patellar dislocation between 2014 and 2024 and had preoperative CT scans were retrospectively reviewed. Fifty patients were randomly selected based on an a priori sample size calculation. For each knee, four axial CT levels were reconstructed: midpatellar level, Roman arc level, 3 cm above the joint line, and the top of the Blumensaat line. A consensus Dejour grade (A–D) was established by an experienced musculoskeletal radiologist and an orthopedic sports surgeon and used as the reference standard. Two orthopedic surgeons independently graded all 200 axial images twice at least 15 days apart. Quadratic weighted kappa (κ) with 95% confidence intervals (CI) was used to assess intra- and inter-observer reliability and agreement with the consensus. Diagnostic accuracy was defined as the proportion of correctly classified cases relative to the consensus and was compared across levels using Cochran’s Q test. Results: When all four levels were combined, intra-observer reliability was almost perfect for both observers (κ = 0.96 and 0.84; exact agreement 91% and 84%), and inter-observer reliability was substantial to almost perfect (κ = 0.72 and 0.78; exact agreement 72–73%). Agreement with the consensus across all levels was moderate (κ = 0.52–0.58; exact agreement 51–52%). Analyzing levels separately, intra-observer κ remained high at all levels, whereas inter-observer agreement and agreement with the consensus varied markedly. The midpatellar level showed only moderate inter-observer reliability and fair-to-moderate agreement with the consensus (κ = 0.36; accuracy 34–40%), whereas the top of the Blumensaat line showed the highest agreement with the consensus (κ 0.69) and the highest accuracy (up to 64%; pooled 61%); however, statistically significant between-level differences were detected in only one observer–time comparison. The 3 cm above the joint line and the Roman arc level demonstrated intermediate performance. Conclusions: Although intra-observer reliability of the Dejour classification is high regardless of axial CT level, both inter-observer agreement and diagnostic accuracy depend strongly on the selected slice. The axial CT level at the top of the Blumensaat line showed a consistent trend toward higher agreement and accuracy relative to the consensus standard and may be used as a standardized reference slice within routine multi-slice CT assessment to improve reproducibility; however, it should complement comprehensive imaging review and clinical evaluation. Full article