Prosthesis

Background: Computer-aided design/computer-aided manufacturing (CAD-CAM) technology is becoming a more significant means of providing prosthodontic treatment due to its impact on clinical performance and patient outcomes. It has been integrated into dental education to allow students to experience digital work-flows. Despite these advancements, many dental students still lack sufficient knowledge of CAD-CAM technologies. Methods: A cross-sectional survey was conducted at the College of Dentistry, Imam Abdulrahman Bin Faisal University. Based on previous studies, a validated questionnaire was distributed to undergraduate dental students and interns. The questionnaire assessed their knowledge and attitudes toward CAD-CAM technology in prosthetic dentistry. Statistical analysis software utilized in the study was the Statistical Package for Social Sciences (SPSS). Results: The responses were analyzed using descriptive statistics, and a chi-square test was used to study the association between knowledge and practice and the study year level. A total of 170 students participated in the study, with a mean age of 22.2 (±2.5) years. The proportion of female participants was 65.9% and the proportion of males was 34.1%. Knowledge varied across academic levels, with fourth- and fifth-year students demonstrating greater theoretical knowledge, while sixth-year students and interns showed more practical experience. Only 3 of the 18 knowledge-related questions received a correct response rate above 70%. Most participants (86%) reported acquiring knowledge from undergraduate courses, and 88% expressed interest in further training. Conclusions: CAD-CAM technology was most commonly practiced for fixed prostheses, and intraoral scanning was the most frequently used digital work-flow. The study highlights the need to improve CAD-CAM education. While lower-level students displayed solid theoretical knowledge, advanced students benefitted from more practical exposure. Increasing hands-on experience and access to digital equipment is essential for preparing students to meet the demands of modern digitalized dentistry. Full article

This study aims to analyze the precision and amount of dental tissue removed during overlay preparation by experienced and less experienced operators, with and without magnification systems. Methods: Sixty-four first upper molar Frasaco Typodonts were divided into four groups: experienced operators with magnification (Group 3, EXP+LOU), experienced operators without magnification (Group 1, EXP), dental students with magnification (Group 4, STU+LOU), and dental students without magnification (Group 2, STU). Preparations including an occlusal reduction of 1.5 mm and an interproximal box of 1 mm width. The prepared teeth were scanned and analyzed using reverse engineering software (Geomagic Control X, Oqton, San Francisco, CA, USA) to evaluate preparation accuracy, dental substance removal, and comparison to a control unprepared tooth. Results: The analysis showed that the average reduction was 32.19%. Group 4 (STU+LOU) showed significantly improved accuracy with magnification compared to Group 2 (STU). Group 3 (EXP+LOU) achieved the best result with an average reduction of 23.96%, while Group 2 (STU) had the worst result with 41.28%. Conclusions: Conservative indirect restorations, such as overlays, effectively preserve dental tissue. Operator experience and magnification systems are crucial for preparation accuracy. Magnification improves precision for less experienced operators, reducing tooth volume loss by 9.1%, and enhances cavity design accuracy, ensuring a better restoration fit and minimizing the marginal gap. Full article

Background: Chronic lumbopelvic pain is often linked to sacroiliac joint dysfunction, where the joint’s complex structure and biomechanics complicate diagnosis and treatment. Variability in load distribution and ligament stabilization within the pelvic ring further contributes to challenges in managing this condition. This study aims to develop a finite element model of the “lumbar spine–sacrum–pelvis” system to analyze the effects of lumbar lordosis, pelvic tilt, and asymmetrical articular gaps on stress and strain in the sacroiliac joint. Methods: A three-dimensional model was constructed using CT and MRI data, including key stabilizing ligaments. Sacral slope angles of 30°, 60°, and 85° were used to simulate varying lordosis, while pelvic tilt was introduced through a 6° lateral rotation. Results: The analysis revealed that sacral slope, ligament integrity, and joint symmetry significantly influence stress distribution. Hyperlordosis led to critical stress levels in interosseous and iliolumbar ligaments, exceeding failure thresholds. Asymmetrical gaps and pelvic tilt further altered the sacral rotation axis, increasing stress on sacroiliac joint ligaments. Conclusions: These findings highlight the importance of maintaining sacroiliac joint symmetry and lumbar–pelvic alignment to minimize stress on stabilizing ligaments, suggesting that treatment should focus on restoring alignment and joint symmetry. Full article

Background: Prostheses are becoming more advanced and biomimetic with time, providing additional capabilities to their users. However, prosthetic sensation lags far behind its natural limb counterpart, limiting the use of sensory feedback in prosthetic motion planning and execution. Without actionable sensation, prostheses may never meet the functional requirements to match biological performance. Methods: We propose an approach for upper limb prosthetic grasp security feedback, delivered to the wearer through direct nerve stimulation proportional to the likelihood of objects slipping from grasp. This proportional feedback is based on a linear regression of the sensors embedded in a prosthetic hand to predict slip before it occurs. Four participants with transhumeral amputation performed pulling tasks with their prosthetic hand grasping an object at predetermined grip forces, attempting to pull the object with as much force as possible without slip. These trials were performed with two different prediction notification paradigms. Results: At lower grasp forces, where slip was more likely, a strong, single impulse notification of impending slip reduced the incidence of object slip by a median of 32%, but the maximum achieved pull forces did not change. At higher grasp forces, where slip was less likely, the maximum achieved pull forces increased by a median of 19% across participants when provided with a stimulation strength inversely proportional to the grasp security, but slip incidence was unchanged. Conclusions: These results suggest that this approach may be effective in recreating a lost sense of grip stability in the missing limb that can be incorporated into motor planning and ultimately prevent unanticipated object slips. Full article

(1) Background: The use of tumor megaprostheses faces challenges, but the published series are typically small and offer limited solutions. Our aim was to compile a large series; describe patient profiles and surgical techniques; analyze prosthetic survival identifying factors affecting survival; and provide a basis for future subanalyses. (2) Methods: This is a retrospective observational multicenter study that included patients with a tumor megaprosthesis in any anatomical location. Demographic, etiologic, and surgical variables were analyzed. Data on complications and survival were also collected. (3) Results: Our series includes a total of 816 prostheses (585 primary, 181 revision, and 50 second revision). The patients’ mean age was 44.2 ± 20.8 years. Primary surgeries were performed on the femur (n = 404; 69.1%), tibia (n = 79; 13.5%), humerus (n = 74; 12.6%), pelvis (n = 20; 3.4%), and scapula (n = 4; 0.7%). Survival following primary surgery was 73.3% at 10 years. No statistically significant differences were found with respect to survival from primary surgery between males and females (p = 0.194), between the different etiologies (p = 0.540), or between the lower and the upper limb (p = 0.618). In contrast, statistically significant survival differences were found when the type of fixation was analyzed (p < 0.001). (4) Conclusions: This study analyzed one of the largest series of patients treated with tumor megaprostheses, demonstrating their acceptable survival and validating them as a treatment option for bone tumors. Full article

Objectives: Among modern metal-free materials, zirconia, a high-performance ceramic material that can only be manufactured through CAM procedures, has certainly exponentially gained popularity thanks to its mechanical strength, biocompatibility, esthetic, and versatility. However, one of the main debates that has been raised in relation to zirconia is its usage as an adhesive material. The present case report describes the clinical outcome of a multidisciplinary case finalized with adhesive minimally invasive zirconia veneers for the treatment of discolored teeth after a 24-month follow-up. Methods: A 19-year-old female patient with discolored upper frontal teeth (first premolar to first premolar) negatively affecting her self-esteem and social life was visited by a prosthodontic specialist. The treatment plan included orthodontic treatment, soft and hard tissue management through surgical procedures, and, lastly, minimally invasive adhesive zirconia veneers. The zirconia veneers bonding was performed under a rubber dam by conditioning the dental substrate by sandblasting the enamel with 40-micron aluminum oxide, etching with orthophosphoric acid 37%, and using a proper adhesive system. Monolithic zirconia restorations were sandblasted with 70-micron aluminum oxide at 0.2 MPa, then cleaned with a specific cleaner, and treated with a primer. Results: At the last follow-up (24 months), neither biological nor mechanical complications were observed. The patient anecdotally reported being very satisfied with the functional and esthetic results obtained. Therefore, the case was considered successful. Conclusions: Within the limitations of the present case report, the reported case on the use of minimally invasive resin-bonded zirconia veneers for the treatment of discolored teeth showed excellent outcomes after a 24-month follow-up. The use of zirconia as an adhesive material seems to be emerging. However, more clinical studies are required to validate the procedure. Full article

Background: Advances in prosthetic technology, especially microprocessor-controlled knees (MPKs), have helped enhance gait symmetry and reduce fall risks for individuals who have undergone transfemoral amputation. However, challenges remain in walking in constrained situations due to the limitations of passive prosthetic feet, lacking ankle mobility. This study investigates the benefits of SYNSYS^®, a new microprocessor-controlled knee–ankle–foot system (MPKA_NEW), designed to synergize knee and ankle movements. Methods: A randomized crossover trial was conducted on 12 male participants who had undergone transfemoral amputation who tested both the MPKA_NEW and their usual MPK prosthesis. Biomechanical parameters were evaluated using quantitative gait analysis in various walking conditions. Participants also completed self-reported questionnaires on their quality of life, locomotor abilities, and prosthesis satisfaction. Results: The MPKA_NEW showed a significant reduction in the risk of slipping and tripping compared to standard MPK prostheses, as evidenced by increased flat-foot time and minimum toe clearance during gait analysis. The MPKA_NEW also improved physical component scores in quality-of-life assessments (Short-Form 36 General Health Questionnaire), suggesting enhanced stability and reduced cognitive load during walking. Conclusions: The MPKA_NEW offers significant improvements in gait safety and quality of life for people who have undergone TFA, particularly in challenging conditions. Further studies are needed to assess the long-term benefits and adaptability across diverse amputee populations. Full article

Background: Ceramic may be an alternative bearing surface that could be used to deal with the negative sequalae associated with the use of metal-on-metal (MoM) hip resurfacing implants, keeping the benefits of hip resurfacing without the risks. The aim of this study is to evaluate the additional financial and logistical implications that MoM hip resurfacing has, in comparison to its ceramic-on-ceramic (CoC) counterpart. Methods: Two different follow up protocols were analysed, according to current practice guidance, on how to follow up with hip resurfacing procedures. Reference costs were identified using the latest national cost collection data and data from the local biochemistry department. The results incorporated the number of hip resurfacings performed nationally. Results: The non-MoM protocol yielded a per operation lifetime follow up cost of £802.50, whereas the MoM protocol yielded a cost of £2132.83 at 25 years. Nationally, according to the 2023 data, this amounted to £561,750 versus £1,492,981 per year, respectively. MoM hip resurfacing is 2.6 times more expensive to be followed up with when compared to the standard protocol. Conclusion: The cost of the follow up of MoM bearings far exceeds that of non-MoM bearings. If CoC hip resurfacing is as clinically effective as MoM hip resurfacing, then the economics favour CoC bearing for resurfacing. Full article

The purpose of this study is to measure the positional accuracy of transfers during the splinting printing process using four biomaterials (two acrylic resins and two bis acrylic resins). Materials and Methods: A master model was constructed for the acrylic simulation of edentulous mandibles with four multiunit analogs (Bioinnovation, Sao Paulo, Brazil) positioned between the lateral incisor and premolar areas. Eighty samples (n = 80) were created in total. Four different dental materials, Duralay (Reliance, Chicago, IL, USA); Pattern Resin LS (GC, Tokyo, Japan) with a ratio of one part liquid and two parts powder; Structur (Vocco, Colonia, Germany); and Protemp (3 M ESPE, Neus, Germany), were used as splints with five samples each. Measurements were obtained for distances between points A, B, C, and D in sequential order through an INSIZE digital calibrator (Inzise, Taiwan, Seng, China). Results: The results were as follows: Distance A: better performance was observed for Pattern Resin (mean = 38.59 mm) and Duralay (mean = 38.58 mm) compared to the base (mean = 38.59 mm); distance B: Pattern Resin (mean = 19.08 mm) and Duralay (mean = 19.07 mm) were compared to the base (mean = 19.08 mm); distance C: no significant differences in relation to the base (prom = 18.85 mm) were shown for the three materials of Pattern Resin (prom = 18.86 mm), Structur (prom = 18.85 mm), and Duralay (mean = 18.85 mm); and distance D: Pattern Resin (mean = 20.46 mm) and Duralay (mean = 20.46 mm) provided lower performance compared to the base (mean = 20.47 mm), ANOVA (Prob = 0.333 > 0.05). Conclusions: Pattern resins and Duralay acrylic resins exhibit better dimensional stability when used as splints for the transfer of multiple dental implants. Full article

Objectives: This study was designed to assess the effectiveness of chitosan as a coupling agent for improving the tensile bond strength of fiber posts. Methods: A total of 91 single-rooted mandibular teeth were root canal-filled. Post spaces were created and categorized into seven groups: Group A (Control), Group B (Silane), Group C (Chitosan), Group D (37% Phosphoric acid + Silane), Group E (37% Phosphoric acid + Chitosan), Group F (10% Hydrogen Peroxide + Silane), and Group G (10% Hydrogen Peroxide + Chitosan). Posts were cemented and tensile bond strength was measured, while the morphological structure of the fiber posts was analyzed using Scanning Electron Microscopy. One-way (ANOVA) and Tukey’s multiple comparison tests were performed at a level of significance of 5%. The percentages of fracture patterns among the groups were compared. Results: 10% Hydrogen peroxide + Chitosan exhibited the significantly highest tensile bond strength (p < 0.001). Adhesive failures were more frequent in Groups A, B, C, and D, whereas cohesive failures within the resin cement were predominant in Groups E, F, and G. Conclusions: The protocol of using 10% hydrogen peroxide followed by a chitosan coupling agent significantly improved tensile bond strengths for glass fiber posts, which highlights the potential of using chitosan as a natural biopolymer and an alternative to synthetic coupling agents to develop more effective bonding strategies for dental restorations. Full article

Background: Complications such as periprosthetic fractures necessitate challenging revision surgeries. In particular, femoral stem revisions can be complicated by poor bone quality, making primary stability and leg length restoration difficult to achieve. Modular fluted tapered stems (MFTSs) have emerged as a viable option for these complex cases. This study aims to describe a reproducible three-step technique for femoral stem revision using MFTSs. The technique focuses on (1) obtaining distal primary stability, (2) restoring leg length, and (3) ensuring overall implant stability. Materials and methods: We conducted a retrospective analysis of ten patients who underwent revision THA using this three-step technique, with a minimum follow-up of 12 months. The mean patient age was 70.7 years, and the average follow-up was 24.2 months. Limits were the small sample size, the lack of clinical outcomes and the short-term follow-up. Results: There was no subsidence, a mean leg length discrepancy of 4 mm (p: 0.604), and no dislocations. However, heterotopic ossifications (HOs) were observed in 25% of patients, although no trochanteric migrations occurred. One patient experienced an intraoperative femoral fracture, which was successfully treated. Conclusions: This three-step approach can break down the revision procedure, making it more accessible to surgeons. The findings suggest that this technique is effective in achieving reliable outcomes in femoral stem revisions, potentially improving the standard of care for patients requiring complex THA revisions. Full article

Prosthetic valve endocarditis (PVE) has undergone significant changes over the past five decades and is currently affecting an aging population, with an increasing prevalence in patients with transcatheter valve implants. The introduction of transcatheter aortic valve replacement (TAVR) represents a significant advance in the field of interventional cardiology and cardiac surgery. The incidence of IE after TAVR has remained stable, with rates similar to those reported after surgical aortic valve replacement. This is despite significant refinements in the TAVR procedure, with less invasive handling and its extension to younger and healthier patients. TAVR should be considered as a potential treatment option for patients with PVE, despite some differences. In terms of evolutionary advances, there have been notable and significant developments in the fields of microbiology and imaging diagnostics. The 2023 Duke-International Society for Cardiovascular Infectious Diseases diagnostic criteria for infective endocarditis now incorporate significant advances in molecular biology and fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography. This has led to a significant enhancement in diagnostic sensitivity for PVE while maintaining the same level of specificity in validation studies. PVE is a deadly disease. A multidisciplinary endocarditis treatment team in a cardiac center is essential to improve outcomes. The availability of novel surgical options allows clinicians to offer an increasing number of patients the opportunity to avoid surgical intervention. Some patients will complete antimicrobial treatment at home. Those with prosthetic valves are eligible for antibiotic prophylaxis before dental procedures. Post-TAVR infective endocarditis (IE) is a subcategory of prosthetic valve endocarditis. This condition presents a particularly complex scenario, characterized by a distinctive clinical and microbiological profile, a high prevalence of IE-related complications, an ambiguous role of cardiac surgery, and a poor prognosis for the majority of patients with TAVR IE. The number of TAVR procedures is set to skyrocket in the coming years, which will undoubtedly lead to a significant rise in the number of people at risk of this life-threatening complication. This review will provide an overview of this rare complication in light of the advent of IE following TAVR. It is crucial to gain a comprehensive understanding of the disease and its associated complications to enhance clinical outcomes. Full article

Purpose: The effectiveness of the customised solutions compared to the conventional ones and the emergence of advanced production technologies, such as Additive Manufacturing (AM) techniques, strengthened the trend towards an enhanced individualization of the clinical treatments. In the present research, the value of topological optimisation (TO) in the manufacturing process of tailor-made orthopaedic appliance (upper-limb orthosis) was analysed. Methodology: From the morphology of a patient’s arm, orthotic models were developed. Nonparametric optimization (Simulia Tosca) was performed, based on the Finite Element Analysis (FEA) program (Abaqus), and contributed to the development of TO orthotic models with diverse levels of volume reduction fraction. The modelling and manufacturing framework for customising orthotic solutions was evaluated with a discussion on the feasibility of lightweight and high-performance products, encompassing production time and cost. Pilot products were produced with a Material Extrusion (MEX) printer. Findings: TO proved to be a practical and valuable approach for the advanced customisation of orthopaedic devices, offering lightweight solutions able to withstand stresses also during patient rehabilitation and remission. From the rapid prototyping perspective, specific strategies must be adopted to prevent the escalation of production costs and time. Originality: The research delves into the overall benefit of implementing an advanced modelling technique within the context of manufacturing highly customised orthoses, analysing how TO activity impacts the rapid prototyping process. Beyond product evaluation, the analysis explores broader implications, including the assessment of feasibility and the development of strategies for integrating the approach into clinical workflows and hospital settings. Full article

Background: Flatfoot deformity is a common condition in children and teenagers that may increase the risk of knee, hip, and back pain. Most of the insoles suggested to treat flatfoot symptoms are not designed to adapt to foot temperature during walking, and they are either too soft to provide support or hard enough to be uncomfortable. Purpose: This study aims to develop an advanced solution to diagnose and treat flexible flatfoot (FFT) using infrared thermography measurements and a hybrid insole reinforced by nitinol (NiTiCu) smart-memory-alloy wires (SMAWs), this super-elastic alloy can return back to its pre-deformed shape when heated, which helps to reduce the local high-temperature points caused by the uneven pressure of FFT. This approach achieves a more uniform thermal distribution across the foot, which makes the hybrid insole more comfortable. Methods: The study involved 16 subjects, divided into two groups of eight flat-footed and eight normal. The procedure includes two parts, namely, designing a prototype insole with SMAW properties based on thermography measurement by using SolidWorks, and evaluating this design using Ansys. Second, a hybrid insole reinforced with SMAWs is customized for flatfoot subjects. The thermography measurement differences between the medial and lateral sides of the metatarsophalangeal line are compared for the normal and flatfoot groups before and after wearing the suggested design. Results: The results show that our approach safely diagnosed FFT and significantly improved the thermal distribution in FFT subjects by more than 80% after wearing the suggested design. A paired t-test reported significant (p-value > 0.001) thermal decreases in the high-temperature points after using the SMAW insole, which was closely approximated to the normal subjects. Conclusions: the SMAW-reinforced insole is comfortable and suitable for treating FFT deformity, and infrared thermography is an effective tool to evaluate FFT deformity. Full article

Immediate loading implant surgery has emerged as a significant advancement in the rehabilitation of edentulous patients. This approach requires meticulous planning and precise execution to ensure successful outcomes. Transferring established intermaxillary and occlusal relationships to the definitive prostheses can be challenging. However, with a digital approach, this procedure can be standardized in cases of fully guided surgery with a flapless technique or by using disposable guides. Conversely, when extensive open flap implant surgery is required, such as in the treatment of severely atrophic patients (e.g., with zygomatic implants or simultaneous bone augmentation), the digital workflow can be demanding. The impression reference technique was proposed to enhance the digital workflow for immediate loading in zygomatic implant rehabilitation. This study aims to describe the impression reference technique, applied to both upper and lower jaws for immediate loading open flap rehabilitations, using standard implants. Full article

Background/Objectives: The potential application of electromyography (EMG) as a method for precise force control in prosthetic devices is investigated, expanding on its traditional use in gesture detection. Variability in EMG signals among individuals is influenced by physiological factors such as muscle mass, body fat percentage, and subcutaneous fat, as well as demographic variables like age, gender, height, and weight. This study aims to evaluate how these factors impact EMG signal quality and force output. Methods: EMG data was normalized using the maximum voluntary contraction (MVC) method, recorded at 100%, 50%, and 25% of MVC with simultaneous grip force measurement. Physiological parameters, including fat percentage, subcutaneous fat, and muscle mass, were analyzed. An extreme gradient boosting algorithm was applied to model the relationship between EMG amplitude and grip force. Results: The findings demonstrated significant linear correlations, with r² coefficients reaching up to 0.93 and 0.83 in most cases. Muscle mass and fat levels were identified as key determinants of EMG variability, with significance coefficients ranging from 0.36592 to 0.0856 for muscle mass and 0.281918 to 0.06001 for fat levels. Conclusions: These results underscore the potential of EMG to enhance force control in prosthetic limbs, particularly in tasks such as grasping, holding, and releasing objects. Incorporating body composition factors into EMG-based prediction algorithms offers a refined approach to improving the precision and functionality of prosthetic control systems for complex motor tasks. Full article

Background/Objectives: The purpose of this in vitro study was to evaluate and compare the internal adaptation and cement film thickness of cast-gold custom post and core (CPC), three-dimensionally (3D)-printed titanium (Ti) CPC, and milled Ti CPC. Methods: Forty-eight 3D printed resin models, simulating a tooth prepared to receive a CPC, were fabricated. Models were randomly assigned to one of three groups (n = 16 per group): (A) cast-gold CPC (control group), (B) 3D-printed Ti CPC, and (C) milled Ti CPC. Following the manufacturing of CPCs, each CPC was cemented using dual-cure polymerizing resin cement. Then, each model/post-and-core assembly was sectioned at the coronal, middle, and apical thirds of the post at a specific point. Each section was photographed using a microscope in a standardized setting (25×). The pixel count for cement surface area was calculated for each image using Adobe Photoshop software. Descriptive statistics of the mean and standard deviation of the cement film thickness around posts were calculated. Kruskal–Wallis and Dwass–Steel–Critchlow–Fligner tests were used for statistical analysis, with a significance level of α = 0.05. Results: Pairwise comparisons in the coronal section revealed a statistically significant difference (p < 0.05) between groups A and B and groups B and C. In the middle section, there was a statistically significant difference (p < 0.05) between groups A and B only. In the apical section, there was a statistically significant difference (p < 0.05) between all groups. Conclusions: Within the limitation of the present study, neither 3D printed nor milled Ti CPC could achieve comparable cement film thickness to cast-gold CPC in all three sections. Cast-gold CPC cement film thickness was found to be more reduced and consistent, thus having superior internal adaptation to 3D-printed and milled Ti CPCs. Full article

Introduction: This preliminary in vitro study aims to evaluate the application of micro-CT in analyzing the microstructural coupling between dental implant fixtures and prosthetic abutments, with an emphasis on understanding the effectiveness and limitations of this technique in dental implantology. Materials and Methods: A search of PubMed, MEDLINE, and the Cochrane Library up to May 2024 identified eight relevant studies that examined different facets of dental implantology, such as osseointegration, implant stability, and the comparative accuracy of micro-CT versus other imaging techniques. A comparative micro-CT radiographic analysis was performed on five different implant fixtures with respective prosthetic and healing abutments, by using SkyScan1174 micro-CT. Results: The reviewed studies demonstrated that micro-CT is reliable for assessing bone quality, implant stability, and the microstructural integrity of dental implants. Micro-computed tomography (micro-CT) studies reveal bone–implant contact (BIC) ratios of 40–80%, bone volume per total volume (BV/TV) values of 20–60%, and detect microgaps as small as 0.3 µm, highlighting its high-resolution capability (5–10 µm) for detailed implant analysis. The comparative analysis of the implant fixtures analyzed the implant–abutment connection, highlighting the relevance of implant design for ensuring stability. Conclusions: Micro-CT analysis has proven to be a valuable tool for evaluating the intricate microstructural properties of dental implants, offering insights into implant stability, bone quality, and osseointegration. The literature reviewed highlights consistent findings that underscore micro-CT’s accuracy and reliability in capturing high-resolution data, suggesting its potential as a standard imaging modality in implant research and clinical assessment. Full article

Background: Grapefruit seed skin particles (GSSPs) have antifungal properties due to the presence of flavonoids. Therefore, it has the potential to display antifungal characteristics when added to acrylic resin, but it could affect the mechanical properties of the resin. This study investigated the effects of adding GSSPs on the mechanical characteristics of 3D-printed denture base resins. Purpose: The aim of the present study was to determine the effects of the addition of GSSPs to 3D-printed acrylic at different concentrations on the degree of conversion (DC), surface hardness, flexural strength, and tensile strength. Methods: In this study, 90 samples were printed with acrylic resin via a Digital Light Processing (DLP) printer. Thirty square samples were used for the surface hardness test. Thirty rectangular samples were used for the flexural strength test, and thirty dumbbell-shaped samples were used for the tensile strength test. These materials were prepared by adding different concentrations of GSSPs (0.0 wt.%, 5.0 wt.%, and 7.0 wt.%), which were determined by a pilot study to be the most effective in 3D denture base resins. The Durometer Shore Hardness Scale (DSHS) was used to measure the surface hardness, and a universal testing machine was employed to gauge the flexural strength and tensile strength. Field emission scanning electron microscopy (FE-SEM) was employed for particle size analysis and fracture behavior determination. Results: Compared with those of the control group, the degree of conversion (DC), surface hardness, flexural strength, and tensile strength of the treated groups significantly improved after the addition of 5.0 wt.% and 7.0 wt.% GSSPs. The FE‒SEM images revealed a decrease in porosity as the concentration of GSSPs increased with a brittle fracture behavior. Conclusions: The addition of GSSPs to 3D-printed acrylic is recommended because of their significant positive impacts on the mechanical properties of 3D-printed denture base resin. Full article