All ceramic dental crowns are widely used in posterior restorations; however, their long-term biomechanical performance remains limited by stiffness mismatch and inadequate stress distribution under functional loading. This study aims to evaluate the biomechanical behavior of zirconia-calcium silicate-silver hybrid crown materials under static and transient dynamic loading conditions and to identify optimal compositions using a multi criteria decision making framework. A three-dimensional finite element model of a crown and tooth with bone system was developed, incorporating nine hybrid compositions (C1-C9) with experimentally derived material properties. Static and transient dynamic loading were applied to simulate physiological mastication. Biomechanical outputs, including von Mises stress and total deformation, were integrated with mechanical properties (hardness, fracture toughness, and elastic modulus) using the TOPSIS method. Results showed that crown stress ranged from 7.46 to 9.78 MPa under static loading and increased to 7.54-10.46 MPa under dynamic conditions (3%-7% increase). Monolithic zirconia exhibited significantly higher stress (up to 19.32 MPa). The periodontal ligament demonstrated a stress reduction of approximately 25%-30% under dynamic loading, indicating its damping role. Deformation remained nearly constant (0.200 mm) across all materials. TOPSIS ranking identified C5 (Ci = 0.777) and C9 (Ci = 0.711) as optimal candidates. The findings demonstrate that hybrid compositions with balanced stiffness improve stress distribution and biomechanical compatibility. The integrated FEA-TOPSIS approach provides a robust framework for optimizing dental restorative materials under realistic loading conditions.

This study aims to develop an innovative bilayered dental implant design featuring a titanium alloy core with a porous composite titanium (Ti) and hydroxyapatite (HA) outer layer to enhance implant stability and patient outcomes. Using SolidWorks 2017, 3D models of the implants and a mandibular bone segment were created. A Finite Element (FE) analysis was then conducted with ANSYS Workbench to assess the mechanical behavior under a 250 N axial compressive load, comparing the bilayered implant to a conventional titanium implant. Variables like porosity (ranging from 10 to 90% in 10% increments), HA content (ranging from 10 to 50% in 5% intervals), and outer layer thickness (2 mm, 1.5 mm and 1 mm) were systematically analyzed. Each configuration was evaluated based on von Mises stress distribution and interfacial strain in peri-implant bone. Results indicated that all porous designs of bilayered implants had significantly lower von Mises stress than traditional implant, with reductions ranging from approximately 69 to 94%, depending on HA/Ti composition and shell thickness. The non-porous bilayer configurations also showed clear stress reductions, with decreases from approximately 72 to 90%, depending on the HA/Ti composition and shell thickness. However, these reductions were slightly lower than those observed in porous designs, with maximal reductions occurring in the porous core of some 2 mm bilayered implant configurations. The combined evaluation of strain and von Mises stress analyses identified the 2 mm core diameter with a 2 mm porous shell as the optimal design, providing favorable microstrain, improved load transfer, and reduced stress concentrations. This modification promotes a more favorable mechanical interaction between the implant and surrounding bone. These findings underscore the potential of bilayered porous implants to improve stability and bone integration, marking a significant step forward in dental implant technology. Further research, including experimental validation, is encouraged to verify these results and investigate other loading conditions, promoting the development of more effective and sustainable dental implant solutions.

This study investigates the synthesis and characterization of hybrid ceramic composites composed of 3 mol% yttria-stabilized zirconia (3YSZ), calcium silicate (CaSiO3), and silver (Ag), developed via the powder metallurgy technique. Nine composite formulations (C1-C9) were prepared systematically by varying the content of CaSiO3 (25, 48, and 68 vol%) and Ag (1, 2, and 3 vol%) in 3YSZ matrix to assess the influence of these additives on the structural and mechanical properties of the sintered bodies. The composites were characterized using XRD, SEM with EDS, and standard mechanical testing methods. Results revealed enhanced densification (from 3918 +/- 41 to 4743 +/- 34 kg/m(3)) and reduced porosity (from 15.096 +/- 0.074 to 0.936 +/- 0.077%) in composites with higher CaSiO3 and Ag content, particularly in the samples C5 (3YSZ with 2%Ag, 48%CaSiO3) and C9 (3YSZ with 3%Ag, 68%CaSiO3) besides significant improvements in hardness (16.631 +/- 0.809 and 17.494 +/- 1.146 HV), fracture toughness (5.236 +/- 0.727 and 5.015 +/- 0.770 MPa m(0.5)), and compressive strength (230.72 +/- 1.854 and 402.387 +/- 1.659 MPa), respectively. The incorporation of Ag notably improved both toughness and antibacterial potential without compromising structural integrity. For the prediction of best composite, TOPSIS-based multi-criteria decision-making (MCDM) analysis showed the best ranked compositions C9 (3% Ag, 68% CaSiO3) and C5 (2% Ag, 48% CaSiO3) as the most suitable for dental applications, exhibiting superior combinations of mechanical and physical properties. The results underscored the promise of Ag- and CaSiO3-reinforced zirconia matrix ceramic composites for advanced dental restorative materials, offering an effective balance of strength, toughness, and biocompatibility.

BACKGROUND:The coronavirus disease 2019 (COVID-19) pandemic has had a profound impact on people's daily lives, resulting in lifestyle changes, social distancing, isolation, as well as economic consequences. An evaluation of the effects of COVID-19 on oral health is necessary. OBJECTIVES:The aim of the study was to evaluate the effects of fixed orthodontic treatment on periodontal health and quality of life in adult patients. MATERIAL AND METHODS:Due to the COVID-19 pandemic, the study methodology was based on a questionnaire consisting of 20 items addressed to patients undergoing orthodontic treatment. The questions concerned the frequency and duration of toothbrushing, brushing techniques as well as the use of auxiliary means of oral hygiene, with the objective of drawing conclusions regarding the oral health of this patient population. Additionally, 5 items adapted from the Oral Health Impact Profile-5 (OHIP-5) were included, asking subjects how frequently they had experienced specific problems during orthodontic treatment. RESULTS:The oral health of adult patients undergoing orthodontic treatment was influenced by the technique, frequency and means of toothbrushing. During fixed orthodontic treatment, pathological changes in periodontal tissues were often observed (23.6-56.4%), along with other conditions influencing patients' quality of life (10.2-81.3%). CONCLUSIONS:Early diagnosis of periodontal conditions during orthodontic treatment is essential for treatment success. Orthodontists should instruct patients on appropriate oral hygiene practices and on detecting changes in periodontal status, as well as should recommend periodontal consultation when needed. Orthodontic treatment in adult patients, through esthetic and functional improvement, should lead to an improvement in psychosocial wellbeing and an increase in quality of life.

The study investigates the development of a continuous carbon fiber reinforced polymer (CFRP) composites mechanical metamaterial that exhibits Negative Poisson's ratio (NPR) properties, designed for higher energy absorption, suitable for automotive bumper materials to withstand the impacts. The objective is to search a proper parametric design with spring-type compression microstructures with gradually stiffer (GS) property and followed by experimental investigation of the properties of the designed structure. Finite element analysis is employed for the integration of high stiffness, auxetic properties, and enhanced failure resistance in the proposed design for lightweight, energy-absorbing structures in crashworthy automotive applications. AHP-TOPSIS multi-criteria decision-making method optimized geometrical variables strut angle (theta = 65 degrees), strut length (L = 10mm), and strut width (b = 4 mm) based on performance parameters such as stiffness, strain energy, NPR, and total strain from the simulated results. Quasi-static compression testing on the fabricated structure validated auxetic behavior, resulting in an experimental Poisson's ratio of -0.36 and stiffness of 1.24 N/mm, which closely aligns with simulation results. The findings from the quasi-static test indicate that the metamaterial exhibits remarkable reusability characteristics and effective energy absorption capability. High-resolution SEM and macroscopic imaging identified several progressive damage modes, such as fiber pull-out, interlaminar delamination, and matrix cracking, which suggest significant energy absorption and structural resilience. The close alignment between simulation and experimental data confirms the mechanical integrity and modeling precision of the CFRP-based metamaterial.

Biodegradable Mg WE43 alloys offer bone-matched stiffness and osteogenic degradation products for mandibular fracture fixation but undergo unpredictable uniform and pitting corrosion that may compromise early stability. Integrating corrosion kinetics into finite element analysis (FEA) could inform implant design and degradation scheduling. To evaluate mechanical stability and degradation of a Mg WE43 mini-plate for mandibular fractures via finite element analysis (FEA), incorporating uniform corrosion and Weibull-distributed pitting corrosion to model stochastic defect formation and growth. A subject-specific mandibular model with a 1 mm angle fracture gap was reconstructed from CT images and combined with detailed SolidWorks designs of a 1 mm-thick WE43 mini-plate and screws. The assembly was discretized with linear tetrahedral elements in ABAQUS/Explicit. A custom VUMAT subroutine implemented continuum damage mechanics-based uniform corrosion and Weibull-distributed pitting corrosion. Boundary conditions fixed the temporal region and applied 150-600 N anterior loads. Validation against experimental mass loss and stress-strain data assessed model accuracy. Over 24 days, simulated corrosion decreased plate stiffness by > 60%, aligning with typical cortical bridging at ~35% residual stiffness. Ultimate tensile strength dropped from 279 to 123 MPa (56% loss) and strain at failure halved. von Mises stress redistribution shifted peak stresses toward corroded fillets, increasing by > 40% under 600 N by day 24. Simulated mass-loss trajectories and stress-strain curves closely matched published experimental benchmarks. The CDM-based FEA framework reliably predicts the time-dependent mechanical degradation of WE43 Mg fixation plates, allowing for the synchronization of implant weakening with bone healing. This predictive tool enables researchers and manufacturers to enhance the implant geometry and corrosion profiles for better safety and effectiveness of biodegradable maxillofacial fixation devices.

This study evaluates the biomechanical influence of surface texturing and hybrid coatings on stress distribution and marginal bone loss (MBL) in dental implants under varying bone loss conditions and axial loading. A parametric three-dimensional finite element model (FEM) of the human mandible was developed, consisting of cortical and cancellous bone layers. Five implant surface textures-Dome, Straight, U-Shape, X-Shape, and V-Shape-were considered, along with four hybrid coatings: hydroxyapatite (HA), HA with 3% tantalum pentoxide (HA3TO), HA with 3% strontium (HA3Sr), and HA with a combination of 1.5% tantalum pentoxide and 1.5% strontium (HA1.5TO1.5Sr). The implants were subjected to static axial loads (100, 150, 200, and 250 N). The V-Shape implant with HA1.5TO1.5SR exhibited the highest implant stress (97.13 MPa at 250 N), exceeding the 35 MPa cortical bone yield threshold, indicating an increased risk of mechanical overload and resorption. Dome-Shape and U-Shape textures demonstrated improved stress distribution, reducing peak stresses and enhancing stability. Hybrid coatings lowered implant stress by 19.65%, mitigating bone remodeling risks. Bone loss amplified stress concentrations, with higher micromotion risks observed in V-Shape and Straight-Shape textures. Surface texturing and hybrid coatings significantly influence peri-implant stress and stability. Based on our findings, Dome-Shape and U-Shape textures, combined with hybrid coatings, offer biomechanical advantages for implant longevity. These findings support the clinical preference for coated, curved-surface implants, particularly in patients with compromised bone quality.

Tibial fractures are a common type of long bone injuries, requiring solid fixation for quicker bone healing and functional recovery. Metallic plates, although widely use, have been associated to stress shielding due to their enhanced stiffness, which can prevent callus formation and adversely affect the long-term outcomes. This study develops and assesses composite bone plates reinforced with unidirectional carbon fibres in different stacking sequences, comparing their biomechanical performance with titanium plates through finite element (FE) analysis. A 3D model of the tibia with a 1 mm oblique fracture gap was reconstructed from scanned bone data and simulated under physiological axial loading (700 N). Stress distribution within cortical and cancellous bone, plates and screws, as well as axial and shear displacements at the fracture site, were analyzed. Results demonstrated that composite plates (particularly configurations C4, C10 and C11) exhibited higher stress transfer to bone and greater controlled fracture gap movements compared with titanium, thereby minimizing stress shielding and promoting favorable conditions for callus formation. Axial and shear displacements with carbon/epoxy plates were 88% and 48% higher, respectively, than titanium plates, without compromising fixation stability. These findings suggest that carbon fibre-reinforced composites offer a promising alternative to metallic implants by balancing flexibility and stability, though further validation with nonlinear material models, cyclic loading and clinical trials is required

Leaf springs serve as essential suspension elements; however, their steel construction contributes to a higher unsprung mass, ultimately diminishing overall efficiency. This investigation examines composite leaf springs as a lighter option, providing enhanced strength-to-weight ratio and performance. The findings underscore the ability to improve ride quality and decrease energy usage, positioning them as a feasible alternative to traditional steel springs. This paper presents the proposal and fabrication of a hybrid composite for the master leaf spring structure. Identifying and simplifying hybrid composite for the master leaf spring structure with well-balanced combination of high tensile strength, toughness, and lightweight properties. These springs incorporate carbon fiber, glass fiber, and Lantor Soric XF cores, providing impressive strength-to-weight ratios and outstanding fatigue resistance while minimizing weight. An integrated AHP-TOPSIS and FEA methodology was employed to enhance the optimization of composite leaf springs. The final laminate is composed of Carbon Fiber (-82 degrees, 1 mm), Glass Fiber (-55 degrees, 0.75 mm), Lantor Soric XF (0 degrees, 2 mm), Glass Fiber (+55 degrees, 1.25 mm), and Carbon Fiber (+82 degrees, 1 mm), determined by performance parameters such as equivalent stress and equivalent elastic strain. This investigation assesses the tensile and flexural properties. The tensile testing conducted according to ASTM D3039 indicated a UTS of approximately 23.5 MPa and a yield strength of around 8.38 MPa. The flexural testing conducted in accordance with EN ISO 14125 revealed a peak load of 0.270 kN and a transverse strength of 89.32 N/mm2. The findings indicate outstanding strength-to-weight characteristics, validating the composite's appropriateness for lightweight, load-bearing applications. The hybrid carbon-glass-foam laminate demonstrates a well-rounded combination of strength, toughness, and lightweight characteristics, positioning it as an excellent substitute for steel in automotive applications where weight is a critical factor, such as in leaf springs.

The durability of implant-supported dental restorations depends heavily on the layer of cement that bonds the prosthetic crown to the framework. However, the influence of cement thickness on the distribution of mechanical stresses within the implant-prosthesis system remains poorly understood. The aim of this study is to evaluate the effect of cement layer thickness on the biomechanical behavior of a metal-ceramic implant-supported restoration. A three-dimensional finite element model of a mandibular segment, incorporating cortical and cancellous bone, a titanium implant and abutment, and a metal-ceramic crown, was developed using SolidWorks software. Three thicknesses of cement were considered: 20, 40, and 60 µm. Static loads were applied to the crown in three directions: axial (100 N), buccal-lingual (50 N), and mesio-distal (23.4 N). The equivalent Von Mises stresses were evaluated at the level of the peri-implant bone, the cement layer, the crown, and the implant-abutment-frame interfaces in order to analyze the influence of cement thickness on stress distribution. The increase in cement thickness led to a decrease in maximum stresses in the peri-implant bone, from 12.32 MPa (20 µm) to 10.49 MPa (60 µm) in cortical bone, and from 2.51 to 1.88 MPa in cancellous bone, as well as a reduction in stresses in the cement layer from 9.74 to 8.47 MPa under axial load. In contrast, stresses in the crown increased with cement thickness, reaching 65.24 MPa for 60 µm. No significant variation in stresses was observed at the implant-abutment-frame interface. The thickness of the cement layer significantly influences the distribution of stresses in implant-supported restorations. A greater thickness protects the peri-implant bone by dissipating loads, but increases the stresses in the crown. Optimizing the thickness of the cement is therefore a key parameter for improving the clinical longevity of implant restorations.

The tribological performance of dental crown materials plays a critical role in their long-term clinical durability. Although 3 mol

ABSTRACT This review aims to critically analyze the fatigue, aging, wear, and interface‐driven performance of contemporary zirconia crown systems and to establish evidence‐based, indication‐specific guidance for clinical material selection. A comprehensive narrative review was conducted focusing on experimental fatigue studies, hydrothermal aging investigations, wear simulations, bonding durability assessments, and long‐term clinical reports of zirconia crowns. Data were synthesized across zirconia systems with differing yttria contents (3Y‐TZP, 4Y‐PSZ, and 5Y‐PSZ) to identify dominant failure mechanisms, quantify performance limits, and evaluate the influence of surface finishing and cementation strategies under simulated oral service conditions. The analysis demonstrates that the long‐term clinical performance of zirconia crowns is governed primarily by fatigue resistance, surface integrity, and interfacial stability, rather than static strength alone. Tetragonal‐rich 3Y‐TZP exhibits superior fatigue reliability and aging resistance, supporting its use in posterior and high‐load conditions. Increased yttria content enhances translucency but reduces fracture toughness, fatigue thresholds, and tolerance to hydrothermal aging, thereby restricting high‐translucency zirconia to low‐stress indications. Polished surfaces significantly reduce antagonist wear, while MDP‐based adhesive cementation improves retention and fatigue performance, particularly in short or minimally retentive preparations. This review provides a clinically performance‐driven synthesis of zirconia crown behavior, integrating mechanical degradation mechanisms with clinical outcomes.

The performance of dental implant depends strongly on how their surfaces interact with the surrounding bone and local microbiological environment. Conventional Ti-6Al-4V implants provide mechanical reliability but lack biological activity needed to promote early osseointegration or limit bacterial adhesion. To address these limitations, this study introduces a piezo-responsive PVDF:PMMA composite coating for Ti-6Al-4V dental implants designed to generate localized electrical cues under simulated masticatory loading. CT- and μCT-based finite element models were employed to evaluate the electromechanical response at both macro and micro scale bone-implant interfaces for different PVDF:PMMA compositions. Among all compositions, the 90:10 PVDF:PMMA coating exhibited highest γ-phase content and produced the largest surface potential under simulated masticatory loads, which was further supported by experimental measurements. Biological assessments further showed that the coating supported hMSC viability and inhibited the growth of common oral pathogens, suggesting potential biological relevance in terms of cytocompatibility antimicrobial advantage. Taken together, the experimental and Finite Element Analysis indicate that optimization of PVDF:PMMA composition provides mechanically activated electrical cues at the implant interface, offering a platform for further investigation of electro-mechanically functionalized dental implants.

Finite Element (FE) analysis is widely used in dental biomechanics, but studies often suffer from insufficient reporting and lack of standardization. This study aimed to develop a consensus-based checklist PRIFED 2026 for improving the transparency, reproducibility, and clinical relevance of FE studies in dentistry. A Delphi process involving 22 international experts was conducted in two stages. Participants, experts in dental FE analysis, reviewed preliminary items derived from existing guidelines and literature. Through three online surveys, panellists rated 86 sub-items on a 9-point Likert scale. Items reaching ≥70% consensus for inclusion were retained. Three online meetings were in parallel held to resolve ambiguities and refine checklist items. The response rate was 76% in the first round, and 18 experts completed the full process. After three rounds, 71 sub-items were included in the final checklist. Notably, 27% of items failed to reach consensus in the first round, reflecting ongoing debate in FE methodology. The checklist covers study design, model construction, boundary conditions, validation, and interpretation of results. The PRIFED 2026 checklist provides a comprehensive and consensus-based framework for reporting FE studies in dentistry. It highlights essential methodological components, including model construction, boundary conditions, and validation strategies, to promote transparency and reproducibility.

To facilitate the healing process in a tibia fracture, the fracture plate should have higher axial movement with lesser twist of the plate at the fracture site along with well-distributed lower stress in the plate and the bone. To achieve these attributes, carbon/epoxy fiber-reinforced laminated composite bone plate is studied as a transverse fractured human tibia shaft of 3-mm fracture gap. Taguchi design of experiment (DOE)-guided finite element analysis results of L32 orthogonal array are used by multi-criteria decision making (MCDM) techniques such as integrated fuzzy AHP–TOPSIS and find out the average performance index to achieve the desired stress distributions and movements. Taguchi optimization method is employed to find the fiber orientations of each lamina for achieving the target properties, which are validated further through finite element analyses. It is found that among the 32 DOE-guided simulations the experiment number 1 having stacking sequence of [−45°/−45°/−45°/−45°/−45°/−45°/−45°/−45°/−45°]S with 0.2 mm lamina thickness is ranked 1 for multi-criteria optimization considering average performance index 0.643106 which also has the maximum axial movement of value 0.291 mm and minimum stress on the plate with 84.378 MPa. Lesser value of stress on the cancellous bone (1.461 MPa) obtained in the exp. no. 32 with the layer orientation is [90°/90°/0°/−45°/45°/−45°/45°/90°/0°]s and thickness 2.5 mm. Lower value of twisting angle (0.3775658°) and stress (15.347 MPa) in cortical bone are obtained using Taguchi optimization method with the layer orientation of [90°/90°/90°/90°/90°/90°/90°/90°/90°]s and [90°/90°/90°/90°/90°/−45°/−45°/45°/45°]s having thickness of 2.5 mm.

Mandible reconstruction stands as a significant area with an advancement technology associated with computer-aided manufacturing (CAM) techniques. These technologies have potential to overcome of lattice structures and enhance scaffold quality. Recently, Osteosynthesis methods have evolved, and influenced for biomaterial selection and manufacturing methodologies for light weight implants. This study investigates the mechanical strength of lattice structures namely diamond, kelvin, and gyroid fabricated using multi-material 3D-printing. The mechanical performance of 3D- printed lightweight lattice structures for mandibular defects were evaluated by experimental method. The design of experiments was developed by varying thickness of lattices and its types. These experimental design results on variation of porosity of lattice structures from 15 % to 70% and surface area to volume ratio from 1 to 17. The experimental study of multi-material lattices structures results high flexural strength compared with compressive and tensile. However, the adhesion breakage of lattices structures was observed in compression and tensile tests. The gyroid lattices structures with least thickness of 1.5 mm, porosity of higher porosity and surface area to volume ratio results optimum mechanical strength for scaffold applications. Tensile, compression, and flexural strengths of 15 MPa, 21 MPa, and 45 MPa were attained by the gyroid 1.5 mm lattice thickness specimen with porosities of 20%, 67%, and 50%, respectively. Finite element analysis using tensile, compression, and flexural modulus values revealed a 32% variation when compared with experimental results.

The ultimate functional lifespan and clinical efficacy of total TMJ replacements are fundamentally reliant on the structural integrity of the implant and the physiological distribution of forces between the device and the recipient bone. The mechanical performance is primarily dictated by two principal factors: the precise spatial positioning of the implant and the inherent mechanical characteristics of its constituent material. This FEA-based computational investigation sought to quantify and contrast the influence of implant positioning and material selection on the resulting stress fields and overall mechanical resilience of the TMJ reconstruction. A patient-specific total TMJ prosthesis was designed and integrated into a 3D mandibular model reconstructed from high-resolution CT scan data. Two materials were considered: Titanium alloy (Ti-6Al-4V) and Polyetheretherketone (PEEK). For each material, three positioning scenarios were defined: (1) an ideal anatomical reference position, (2) a 2 mm lateral displacement, and (3) a 3 mm medial displacement. The bone-prosthesis assemblies were analyzed in Abaqus under a static chewing load of $\mathbf{2 6 2. 2 8 ~ N}$. The results showed that prosthesis positioning significantly impacts the stress distribution pattern. For the titanium model, the lateral position was identified as providing the best combination of mechanical stability (lowest displacement) and host bone protection (lowest bone stress, 90.74 MPa), a configuration that mitigates the risk of fixation failure. Material comparison showed that Titanium (Ti-6Al-4V) implants provided superior stability (lower displacement), whereas PEEK implants, possessing an elastic modulus closer to that of bone, facilitated a more physiological load transfer and mitigated the stress shielding effect. Consequently, the optimal material decision must be patient-specific, balancing the immediate requirement for maximal mechanical stability against the crucial need for long-term host bone viability.

There has been an upsurge in applications of dental implant over last few decades and FEM has played an essential role in rapid development of dental implant. In spite of that, dentists are still doubtful regarding the use of splinted or non-splinted dental implants. Few studies state that splinted implants are better than non-splinted dental implants from a biomechanical viewpoint while few studies state that non-splinted dental implants are better for oral hygiene and retreatment point of view. This study presents a biomechanical aspect by analyzing distribution of stress in splinted as well as non-splinted dental implant based on occlusal loadings. The results state that splinted dental implants cause uniform stress distribution in the mandibular region and thus are favorable from biomechanical standpoint.