Search Results (47)

Background/Objectives: Surface modifications of implants aim to mimic bone tissue and provide a more suitable environment for cell metabolism. Several modifications have been proposed, and in addition to evaluating the effects of these treatments on cell behaviour, it is also essential to determine the response of these cells to an inflammatory environment. This investigation evaluated the behaviour of murine pre-osteoblasts seeded onto acid-treated titanium and zirconia surfaces subjected to inflammatory challenge. Methods: Discs were manually polished using abrasive paper and then subjected to surface modification by hydrofluoric acid through distinct protocols according to each material. Surface topography and roughness were determined using scanning electron microscopy (SEM) and ImageJ software (Version 2.16). Then, MC3T3 cells were seeded onto the discs for 24 h and subsequently exposed to lipopolysaccharides (LPSs) from Porphyromonas gingivalis (P. gingivalis) (1 μg/mL) for 4 h at 37 °C. The cells were then evaluated for viability, oxidative response, and gene expression of pro-inflammatory cytokines. Results and Conclusions: Both materials were affected by acid treatment, resulting in more irregular topography and increased surface roughness. Full article

The long-term success of implant-supported prostheses (ISPs) is strongly influenced by material selection, which affects stress distribution within the implant system and surrounding cortical bone. This study aimed to assess the biomechanical behavior of a four-unit ISP supported by two implants in the posterior region, using different framework and superstructure material combinations through dynamic finite element analysis (FEA). Methods: A three-dimensional (3D) edentulous mandibular model was created using Mimics software, with two implants placed in the first premolar and second molar regions. Four framework materials—titanium (Ti), glass fiber–reinforced composite (GFRC), 3Y-TZP zirconia, and polyether ether ketone (PEEK)—were combined with two superstructure materials, 5Y-TZP zirconia and resin-matrix ceramic (RMC), forming eight groups. Dynamic loading simulated chewing forces, and stress distribution was analyzed using the von Mises criterion. Results: The results demonstrated that 3Y-TZP zirconia frameworks generated the highest stress values across implants, abutments, and cortical bone. RMC crowns consistently produced lower stress than 5Y-TZP zirconia across all the groups. PEEK showed the highest displacement, followed by GFRC, zirconia, and Ti. Conclusion: Materials with higher Young’s modulus tended to exhibit greater stress transfer to the implant, implant components, and cortical bone. In contrast, polymer-based materials may show a tendency toward greater deformation and displacement compared with metallic and ceramic materials. Full article

Background and Objectives: Intramedullary headless screw (IMHS) fixation is a minimally invasive and biomechanically stable option for metacarpal fractures. However, the suitability of commonly used screw diameters may be limited by the morphometric features of the intramedullary canal. This study evaluated the isthmus morphology of the second to fifth metacarpals using computed tomography (CT)-based morphometric analysis and virtual screw simulation. Materials and Methods: A retrospective morphometric study was conducted using 75 hand CT scans, representing 300 metacarpals (second to fifth). Three-dimensional reconstructions were created with Mimics software (Materialise, Leuven, Belgium), and the isthmus level was identified by serial axial CT analysis. Canal diameters were measured at this level, and bone-specific virtual screw models were generated in Rhinoceros 3D and imported into Mimics for virtual implantation and canal conformity assessment. Feasibility rates were calculated for screw diameters between 2.75 mm and 4.00 mm. The effects of age and gender were also analyzed. Results: The fourth metacarpal had the smallest mean isthmus diameter (2.64 ± 0.89 mm), while the fifth had the largest (3.21 ± 0.84 mm). Feasibility decreased as screw diameter increased across all metacarpals. The fourth metacarpal showed the lowest compatibility, with feasibility rates of 10.7% for 3.5 mm screws and 4.0% for 4.0 mm screws. In contrast, the fifth metacarpal had the highest feasibility at smaller diameters, with 74.7% compatibility for 2.75 mm screws and 62.7% for 3.0 mm screws. Positive correlations were found between age and isthmus diameters of the second and third metacarpals, indicating age-related canal widening. Conclusions: The anatomical feasibility of IMHS fixation in the second to fifth metacarpals is influenced by isthmus morphology. The fourth metacarpal appears to be the most restrictive, particularly for screws ≥ 3.5 mm. These findings support individualized CT-based preoperative templating rather than standardized implant selection to improve screw canal compatibility and reduce cortical compromise risk. Full article

Three-dimensional (3D) anatomic modeling derived from high-resolution medical imaging, such as computed tomography (CT) and magnetic resonance imaging (MRI), has been increasingly adopted in preclinical testing and device development. This white paper describes a cardiac-specific workflow that integrates 3D printing and silicone molding for support device development and procedural simulation. Patient-derived computed tomography angiography data were segmented using FDA-cleared medical modeling software to isolate the left ventricular anatomy and were further processed in computer-aided design (CAD) to ensure accurate physiological wall thickness and structural fidelity. Material jetting 3D printing was performed on a Stratasys J750 using material distributions designed to mimic the mechanical properties of myocardium, thereby approximating myocardial compliance. In parallel, stereolithography apparatus molds were designed from the left ventricle CAD model to cast transparent, pliable left ventricular models in Sorta-Clear™ 18 silicone. The 3D-printed models preserved intricate morphological detail and were suitable for mechanical manipulation and device deployment studies, whereas silicone models offered tunable mechanical properties, transparency for visualization, and durability for repeated use. Together, these complementary modalities provided rapid manufacturing capability and application-relevant physical representation. Case-specific parameters, strengths, and limitations of both models in enhancing patient care and device testing are highlighted, with relevance to heart failure applications. Current knowledge gaps, workflow and integration challenges, and future opportunities are identified, positioning this work as a reference framework for continued innovation in anatomic modeling. Within the collaborative framework of Mayo Clinic’s Anatomic Modeling Unit and Simulation Center, this integrated modeling workflow demonstrates the value of multidisciplinary collaboration between engineers and clinicians. Clinically, these patient-specific left ventricular models may enable pre-procedural device sizing and positioning and may support simulation of mechanical circulatory support (MCS) deployment while identifying possible anatomic constraints prior to intervention. This workflow has direct applicability in advanced heart failure patients undergoing MCS support, such as the Impella axillary MCS device or the durable LVAD, with potential to reduce procedural uncertainty while reducing complications and improving peri-procedural outcomes. Additionally, these models also serve as high-accuracy educational tools, enabling trainees and multidisciplinary care teams to visualize and possibly rehearse procedural steps while gaining hands-on experience in a risk-free environment. Full article

Objectives: This study aimed to evaluate maxillary arch width increase in juvenile patients requiring space gain, but without skeletal transverse discrepancies necessitating orthopedic expansion. The comparison focused on the effects of Rapid Maxillary Expansion (RME) using Hyrax expanders and dentoalveolar expansion via Invisalign First. Methods: This retrospective longitudinal study analyzed digital dental models of 38 patients (19 males and 19 females, aged 8 ± 2 years) undergoing maxillary expansion at the Department of Biomedical, Surgical, and Dental Science, Fondazione IRCCS Ca’ Granda, Ospedale Maggiore Policlinico (Milan, Italy). Patients were divided into two groups: one treated with Hyrax expanders (n = 19) and the other with Invisalign First (n = 19). Intraoral scans were taken before (T0) and after treatment (T1), and measurements were performed using Mimics Materialize 21.0 software. Statistical analysis included t-tests, ANOVA, and regression models to assess differences in maxillary expansion between groups. Results: Both groups showed statistically significant transverse arch increases (p < 0.01). Hyrax achieved greater expansion at the deciduous canine level, while Invisalign showed more at the deciduous molar level. First permanent molar expansion was similar. ICC for reliability was excellent (>0.97). No significant differences in sex or Angle class distribution were observed. Conclusions: Hyrax and Invisalign First both produce measurable maxillary expansion, but they serve distinct roles. While Hyrax expanders provide rapid skeletal expansion, Invisalign First offers a less invasive alternative for dentoalveolar widening with controlled force application. They should not be used interchangeably. Appliance selection must be tailored to the severity and nature of the transverse deficiency. Full article

Background and Objectives: The sacrum is formed by five fused vertebrae and connects the lumbar spine to the coccyx. It has four pairs of foramina for sacral nerves and shows important anatomical variations. This study aims to analyze the frequency of atypical sacral morphology in the Korean population using 3D reconstruction of postmortem computed tomography (PMCT) images, and to provide a systematic classification and morphological characterization. Materials and Methods: A total of 29 PMCT datasets (10 males, 19 females) from the National Forensic Service were used to generate 3D sacral models with Mimics software for the analysis of atypical sacral morphology. Key morphometric parameters, including sacral width (SW), sacral length (SL), sacral foramina distances (SFD1, SFD2), sacral vertebral heights (SH1, SH2), sacral curvature (SC), and sacral index (SI), were measured. Sacral foramina were categorized into three groups based on completeness, and auricular surfaces were classified into three types according to their vertical position. Results: Median values for sacral dimensions were as follows: SW 95.3 mm, SL 118.6 mm, SFD1 36.1 mm, SFD2 28.8 mm, SH1 28.0 mm, SH2 29.7 mm, SC 0.92, and SI 0.78. Sacral foramina variations were identified in 12 of 29 cases (41.4%) as incomplete, including one case with an incomplete upper opening. No significant sex-based differences were found in foramen or auricular surface types, although females showed higher values for SW and SI (SW: 97.2 mm, SI: 0.86). Correlation analysis revealed positive associations between SL and both stature (r = 0.635) and weight (r = 0.645), and negative correlations between SI and stature (r = −0.663), SL (r = −0.921), and SC (r = −0.845). Two cases (6.8%) exhibited sacralization, while the remaining 25 cases had the configuration of five lumbar vertebrae and six sacral segments. Conclusions: Our findings support the notion that atypical segmentation patterns are more prevalent than sacralization. Atypical sacral morphology was observed in 29 cases (19.8%), most commonly involving a normal lumbar spine with six sacral segments. These findings highlight the relevance of sacral variation in clinical and anatomical contexts. Full article

Background and Objectives: Femoroacetabular impingement (FAI) morphology refers to structural abnormalities that can alter normal joint mechanics and potentially lead to early onset osteoarthritis. Although commonly diagnosed in symptomatic individuals, such morphological features are also found in asymptomatic adults, underlining their relevance for early detection and preventive management. This study aimed to evaluate the three-dimensional congruence of hip joint surfaces in relation to FAI and the morphology of asymptomatic hips with potential FAI features. Materials and Methods: Retrospective three-dimensional reconstructions of 86 hip joints were created using Mimics software from computed tomography (CT) scans of the lower abdomen and pelvis retrieved from the radiology archive. CT scans belonged to individuals with preserved anatomical integrity (20 females, 23 males, bilateral hips), aged 24–76 years. Lateral center-edge angle (LCEA) and alpha angle measurements were obtained from reconstructions to assess the risk of asymptomatic FAI. Results: Significant gender differences were found in alpha angles. The mean right alpha angle was 46.57 ± 3.12° in females and 49.28 ± 6.66° in males p = 0.046, while the mean left alpha angle was 43.75 ± 5.53° in females and 47.37 ± 5.77° in males p = 0.021. An alpha angle >50°, suggestive of cam type FAI, was present in 25.6% of right hips and 13.9% of left hips. LCEA values showed no significant gender or side differences, with a mean of 30.21 ± 8.96° across the cohort. Conclusions: Three-dimensional evaluation of asymptomatic hips revealed FAI-consistent morphology in a notable proportion of individuals, particularly males. Cam-type deformities tended to occur bilaterally, whereas pincer-type morphologies were more sporadic and often unilateral. Increased alpha and LCEA measurements in asymptomatic individuals suggest that FAI morphology may exist subclinically without always indicating disease. Future studies incorporating longitudinal imaging and clinical follow-up are needed to clarify the prognostic significance of these findings. Full article

Background: This study aimed to compare the stress distribution and fracture resistance of dental tissues and restorative materials with varying adhesive layer thicknesses and different restorative materials. Methods: A caries-free mandibular first molar (tooth #36) was scanned using CBCT. The scanned files were processed in Mimics 12 software for segmentation of enamel, dentin, and pulp tissues and then exported to STP format. Cavity preparations (DO, MO, MOD, and O) were designed in SolidWorks 2023. Bulk-fill composite, conventional composite, and hybrid composite were used for restorations with adhesive layers of 10, 15, and 20 μm thick. Stress distribution and fracture resistance were analyzed using 3D finite element analysis. Results: The highest stress values in enamel, dentin, and adhesive material were observed in models restored with bulk-fill composite, while the highest stress values within the restoration were found in models restored with hybrid composite. As the adhesive layer thickness decreased, stress accumulation within the restorative material increased. Enamel fractures occurred first in models with bulk-fill composite. Among restorative materials, fractures initiated first in models restored with hybrid composite, while the latest fracture onset was observed in models with bulk-fill composite. Conclusions: Restorative materials with low Young’s modulus cause excessive stress accumulation in enamel and dentin, leading to early fracture of these tissues. In contrast, materials with a high Young’s modulus transfer more stress to the restoration, causing premature fracture of the restorative material. Full article

This study proposes a design and initial validation of a biocompatible artificial human heart that mimics beating behavior. Advanced geometrical modelling in SolidWorks software (student version) and finite element analysis (FEA) using ANSYS 2024 (student version) has been made, including Neo-Hookean hyper elastic material i.e., medical-grade silicone for cardiac tissue replication. The design consists of four-chambers, where the chambers’ dimensions were optimized to maintain uniform pressurization. We observed controlled wall displacement and low stress under simulated physiological conditions with our model. These results provide the basis of the design to be used as an effective teaching platform for medical students and a platform to future progress toward an implantable circulatory assistance device. These findings provide deeper insights into cardiac biomechanics and represent a novel approach to managing a growing need for cardiac alternatives to transplantation. Additionally, the report details the application of pressure and records displacement and stress outcomes from FEA. Through integration of hyper elastic material behavior into the design framework, the research provided critical insights into the performance of silicone-based models, informing future experimental studies and clinical translation. Full article

Background and Objectives: Bone regeneration (BR) is a cornerstone technique in reconstructive dental surgery, traditionally using either barrier membranes, titanium meshes, or perforated non-resorbable membranes to facilitate bone regeneration. Recent advancements in 3D technology, including CAD/CAM and additive manufacturing, have enabled the development of customized scaffolds tailored to patient needs, potentially overcoming the limitations of conventional methods. Materials and Methods: A scoping review was conducted according to the PRISMA guidelines. Electronic searches were performed in MEDLINE (PubMed), the Cochrane Library, Scopus, and Web of Science up to January 2025 to identify studies on digital technologies applied to bone augmentation. Eligible studies encompassed randomized controlled trials, cohort studies, case series, and case reports, all published in English. Data regarding digital workflows, software, materials, printing techniques, and sterilization methods were extracted from 23 studies published between 2015 and 2024. Results: The review highlights a diverse range of digital workflows, beginning with CBCT-based DICOM to STL conversion using software such as Mimics and Btk-3D^®. Customized titanium meshes and other meshes like Poly Ether-Ether Ketone (PEEK) meshes were produced via techniques including direct metal laser sintering (DMLS), selective laser melting (SLM), and five-axis milling. Although titanium remained the predominant material, studies reported variations in mesh design, thickness, and sterilization protocols. The findings underscore that digital customization enhances surgical precision and efficiency in BR, with several studies demonstrating improved bone gain and reduced operative time compared to conventional approaches. Conclusions: This scoping review confirms that 3D techniques represent a promising advancement in BR. Customized digital workflows provide superior accuracy and support for BR procedures, yet variability in protocols and limited high-quality trials underscore the need for further clinical research to standardize techniques and validate long-term outcomes. Full article

In computed tomography (CT)-based evaluation of the extent of cystic changes in the lungs of patients with cystic lung diseases, such as Lymphangioleiomyomatosis (LAM), there is a lack of a lung phantom containing air-filled cavities that mimic pulmonary cysts to calibrate the measurement of cystic volumes from CT scans. We describe an easy-to-replicate cystic lung phantom consisting of basic lung structures of a trachea and two lung compartments. The lung compartments contain air cavities of varying sizes to mimic cystic lesions. The lung compartments are made of a foam material recommended by NIST to simulate the radiodensity of human lung parenchyma. In tests performed on a clinical scanner, various structures in the lung phantom were correctly recognized by two types of lung analysis software. The resulting cystic volume measurements revealed the relationship between the size of the cysts and the accuracy of the measurement. The significant finding was that the volumes of individual cysts were underestimated for small cysts. The error increased with decreasing cyst sizes. Such underestimation has not been mentioned previously and deserves the attention of clinicians using CT scans to assess the cyst burden in the lungs, particularly in patients presenting with numerous small pulmonary cysts. Full article

Low-energy bone fractures refer to injuries that occur from minimal trauma or impact. These fractures are often a result of activities, such as falls from standing height or minor accidents, where the force exerted on the bone is insufficient to cause a break under normal conditions. To design an effective orthotic splint, it is critical to select the appropriate material that mimics the mechanical properties of traditional materials like plaster, which has long been used for immobilization purposes. In this case, Ansys CES Edupack 2025 software was utilized to evaluate and identify materials with mechanical characteristics similar to those of plaster. The software provided a list of six materials that met these criteria, but selecting the most suitable material involved more than just mechanical properties. Three different multicriteria decision-making methods were employed to ensure the best choice: TOPSIS, VIKOR, and COPRAS. These methods were applied to consider various factors, such as strength, flexibility, weight, cost, and ease of manufacturing. The results of the analyses revealed a strong consensus across all three methods. Each approach identified PLA (Polylactic Acid) as the most appropriate material for the orthotic design. Following the material selection process, simulations were conducted to assess the structural performance of the orthotic splint. The results determined that the minimum thickness required for the PLA orthosis was 4 mm, ensuring that it met all necessary criteria for acceptable stresses and deformations during the four primary movements exerted by the wrist. This thickness was sufficient to maintain the orthosis’s functionality without compromising comfort or effectiveness. Moreover, a significant improvement in the design was achieved through topological optimization, where the mass of the preliminary design was reduced by 9.58%, demonstrating an efficient use of material while maintaining structural integrity. Full article

Objective: Frontal sinus surgery is still challenging for surgeons; the frontal osteotomy with the preparation of a frontal bone flap to access the sinus is usually hand-crafted by experienced surgeons. The objective of our study is to present a fully digital protocol for the manufacturing of “in-house” surgical cutting guides, customized to the patient’s anatomy, to perform precise frontal sinus osteotomy, showing the costs, times, and intraoperative complications reduction. Materials and Methods: A prospective study was conducted on 12 patients with complex pathologies involving the frontal sinus who underwent frontal sinus osteotomy in the Maxillofacial Surgery Unit of the Federico II University of Naples, from January 2021 to April 2025, considering the last surgery in November 2023. The same digital protocol to manufacture the surgical cutting guide was used for all the 12 patients. The first step was to upload the preoperative CT images in DICOM format to the software Mimics Medical to perform a rapid segmentation of the skull region of interest to create a 3D object and to identify the frontal sinus margins and the osteotomy lines. The second step was to realize the surgical cutting guide, incorporating the design of titanium plates to fix onto the skull in order to make a precise osteotomy. The final digital step was to export the cutting guide 3D object in the software “Formlab-Form 3B” to print the model with a specific resin. The model was then used during the surgery to perform the precise frontal osteotomy by piezo surgery. The clinical outcomes, in terms of complications and recurrences, were then recorded. Results: In all the patients, no intraoperative complications occurred; the median follow-up was 31.7 months and at one year of follow-up only one patient experienced a recurrence. The mean operative time was about 4 h, with a frontal osteotomy time of about 23 min. Digital protocol time was about 4 h while printing times were between 2 and 4 h. Conclusions: This “in-house” protocol seems to demonstrate that the use of intraoperative templates for the realization of the frontal sinus osteotomy reduces preoperative and intraoperative costs and times, reducing the risk of intraoperative complications, and also allows less experienced surgeons to perform the procedure safely. Obviously, this study is to be considered a “pilot study”, and other studies with large cohorts of patients will have to confirm these promising results. Full article

Aim: Class II Division I malocclusion poses significant challenges in orthodontics. The combination of a Herbst appliance and miniscrew anchorage emerged as a practical solution to improve skeletal and dental outcomes. This study employed finite element analysis to evaluate the biomechanical effects of a miniscrew-supported Herbst appliance on mandibular advancement and dentition movement. Methods: High-definition CBCT scans captured the maxilla and mandible’s detailed dental anatomy. The scans were stored in DICOM format for seamless integration with Mimics software (Mimics Innovation Suite research version 21.0, Materialise NV, Leuven, Belgium) for 3D reconstruction and model refinement. The appliance, designed with a maxillary fixed palatal arch and mandibular acrylic splint connected by telescoping rods, incorporated titanium TADs and elastic chains. STL models were optimized in Geomagic x Design for finite element analysis in Abaqus, assigning validated mechanical properties for materials. Tetrahedral meshing and realistic boundary conditions simulated biomechanical interactions. Tetrahedral C3D4 elements were used for meshing, ensuring a balance between computational efficiency and detailed anatomical representation. Tetrahedral meshing and realistic boundary conditions simulated biomechanical interactions. Dynamic simulations in CATIA evaluated mandibular movement. FEA analyzed displacement across dentoalveolar structures along the X, Y, and Z axes to assess treatment efficacy and biomechanical stability. Results: The Z displacement analysis revealed that the incisal edges of the lower central, lateral, and canines shifted lingually by 0.41, 0.4, and 0.47 mm, respectively. Additionally, the apices of the lower central, lateral, and canines displaced backwards by 0.05 mm, 0.05 mm, and 0.07 mm, respectively. Conclusions: The appliance facilitated mandibular advancement, bodily retracted the lower incisors, well-controlled the upper ones, and mesial-tipped the upper posterior teeth. In contrast with traditional functional appliances, it caused the lower anterior teeth to move backwards, while skeletal anchorage overcame some shortcomings of nonsurgical treatments. This method might be a good treatment option for growing skeletal Class II patients. Full article

This research paper explores the development of AI-optimized lattice structures for biomechanics scaffold design, aiming to enhance bone implant functionality by utilizing advanced human–AI systems. The primary objective is to create scaffold structures that mimic the mechanical properties of natural bone and improve bioactivity and biocompatibility, adapting to patient-specific needs. We employed polylactic acid (PLA), calcium hydroxyapatite (cHAP), and reduced graphene oxide (rGO) as base materials, leveraging their synergistic properties. The scaffolds were intricately designed using nTopology software (nTop 5.12) and fabricated via 3D printing techniques, optimizing for biomechanical load-bearing and cellular integration. The study’s findings highlight a notable enhancement in the mechanical properties of the scaffolds, with the Gyroid lattice design demonstrating a 20% higher energy-absorption capacity than traditional designs. Thermal and chemical analysis revealed a 15% increase in the thermal stability of the composites, enhancing their resilience under physiological conditions. However, the research identified minor inconsistencies in filament diameter during 3D printing, which could affect scaffold uniformity. These findings underscore the potential of integrating AI-driven design with advanced material composites in revolutionizing orthopedic implant technologies. Full article