Replacement Options Research Articles

Fate of Semilunar Valves From Discarded Hearts at the Time of Pediatric Heart Retransplantation.

Partial heart transplantation (PHT) is a novel procedure for children in need of a growing valve replacement option. One challenge is identifying suitable donor valves. Semilunar heart valves from patients receiving a retransplant may be a source, however their functionality and growth potential especially at the time of retransplant are unknown. We aimed to assess growth and function of these valves. Data from patients undergoing a retransplant at a single institution were analyzed. Echocardiograms were compared following the primary transplant and immediately before retransplant to assess growth and valve function. Thirteen patients were included. Recipient and donor ages at the primary transplant were median (range): 2 years (0-13) and 3 years (0-40), respectively. The median time to retransplant was 11 years (2-21). There was an overall growth across all semilunar valve measurements; aortic valve annulus diameter (mean increase ± standard deviation): 0.2 ± 0.12 cm, aortic root: 0.29 ± 0.16 cm, and pulmonary valve annulus: 0.5 ± 0.34 cm; all p < 0.05. The growth rate of valves was higher in younger patients and showed a better correlation with graft age relative to recipient age: aortic valve annulus growth R2: 0.61 (graft age) versus 0.54 (recipient age); aortic root R2: 0.73 versus 0.57; pulmonary valve annulus R2: 0.94 versus 0.86. No patients had clinically significant regurgitation or stenosis on the latest echocardiogram. All except one patient's measurement had valve Z-scores within ±2 at retransplant. Explanted hearts from patients undergoing retransplantation could be considered an additional source of semilunar valves for PHT. Valves from these hearts were found to function normally and grew in proportion with the recipient's body. Valves from younger donors/recipients demonstrated a more rapid growth rate.

Rethinking mechanical heart valves in the aortic position: new paradigms in design and testing

Bileaflet mechanical heart valves (MHV) remain a viable option for aortic valve replacement, particularly for younger patients and patients from low- and middle-income countries and underserved communities. Despite their exceptional durability, MHV recipients are at increased risk of thromboembolic complications. As such, the development of the next generation of MHVs must prioritize improved thromboresistance and aim for independence from anticoagulant therapy. However, innovation in MHV design faces several challenges: strict performance and biocompatibility requirements, limited understanding of the mechanisms underlying MHV thrombosis, and a lack of effective testing methodologies to assess how design variations impact both hemodynamic performance and thrombogenicity of MHVs. This paper reviews the emerging paradigms in MHV design, materials and surface modifications that may inspire the development of a new generation of MHVs for aortic valve replacement. We also discuss challenges and opportunities in developing experimental and numerical approaches to achieve a more comprehensive understanding of MHV flow features and the mechanisms of flow-induced blood clotting.

Joint replacement for rheumatoid arthritis: When, why, and how! Insights from an orthopedic surgeon.

The past several decades have seen significant advancements in joint replacement surgery for rheumatoid arthritis (RA). Joint replacement procedures have become vital options for patients with severe joint damage and functional impairment. There has been an increased emphasis on personalized surgical strategies that tailor joint replacement decisions based on a patient's unique clinical characteristics and the extent of joint damage. Achieving personalized outcomes requires clearly understanding the patient's baseline joint function and comparative data on different prosthetic designs and techniques. Comprehensive preoperative preparation is fundamental to ensuring surgical success. This includes thoroughly evaluating the patient's medication history, the extent of joint damage, and overall systemic health. Despite careful surgical planning, trade-offs between different replacement options often remain. In this paper, we review the perioperative preparation and surgical techniques in joint replacement surgery for RA. Additionally, we discuss the challenges in optimizing postoperative rehabilitation and preventing complications, which remains a key factor in achieving full recovery and maximizing the benefits of joint replacement surgery for RA patients. The pathological basis of RA is an acute or chronic inflammation of the synovial membrane. As a result, synovial joints throughout the body can be affected, including joints in the upper limbs (shoulders, elbows, wrists, metacarpophalangeal joints, and interphalangeal joints) as well as in the lower limbs (hips, knees, and ankles). If drug treatments fail to control inflammation adequately, recurrent synovitis in the affected joints can lead to swelling, effusion, cartilage erosion, and eventual cartilage loss. Due to decreased weight-bearing, along with the use of various medications-particularly glucocorticoids-widespread subchondral bone osteoporosis, bone marrow edema, and bone destruction may occur, leading to cystic degeneration and even extensive bone defects. In the advanced stages of RA, deformities can develop, such as "boutonniere" and "swan-neck" deformities in the fingers, ulnar deviation of the wrist, "otto pelvic" due to central acetabular erosion and dislocation of the hip, varus or valgus deformities of the knee, flexion contractures, and destruction or fusion of the ankle joint. The foot can also present deformities, such as hallux valgus and overlapping toes. Total joint replacement surgery has become the most effective surgical treatment for severe joint destruction and deformities in late-stage RA. Among all joints, the hip and knee are the most frequently replaced, as their dysfunction severely impacts the patient's ability to walk, leading to disability and loss of mobility. In this review, we provided a comprehensive discussion on the perioperative management of patients with RA, focusing on preoperative preparation, intraoperative planning, and postoperative rehabilitation and assessment. Rheumatology Department Perspective on Preoperative Preparation for RA Joint Replacement Surgery.

Awareness as an alternative to abandonment? Critical notice of Herman Cappelen’s The Concept of Democracy

Herman Cappelen’s book The Concept of Democracy makes a case for ‘abolitionism’, that is, abandonment of the word ‘democracy’ and related terminology (‘D-words’). Cappelen’s strategy includes a direct argument for abandonment, aiming to show that D-words are meaningless; and an indirect argument, based on a comparison of abandonment with other options (for instance, replacement or amelioration). In this critical notice, I focus on his comparative case, arguing that the competing options and their respective challenges are not so well demarcated—where this negatively affects the abandonment proposal. Furthermore, I present and defend a yet unexplored alternative: awareness. Awareness is a worthy candidate for its little costs and significant benefits in comparison to abandonment, thus deserving consideration alongside the options assessed by Cappelen.

Enhanced high-sensitivity multi-layer neutron detector based on LiF:ZnS(Ag) scintillator

This study proposes a novel, highly sensitive neutron detector design utilizing a unique multi-layered configuration. Each layer consists of a LiF: ZnS(Ag) scintillator coupled with a transparent neutron moderator that also functions as a light guide for the Silicon Photomultiplier (SiPM) light sensor. This design offers a cost-effective and readily available alternative for existing neutron detectors. The research focused on optimizing a single layer for maximum sensitivity and proper gamma rejection capabilities. This optimized configuration is then replicated to form the multi-layer detector. A primary challenge with the LiF:ZnS(Ag) scintillator is its inherent opacity, limiting its width and consequently, its detection efficiency. Our proposed multi-layer structure addresses this limitation by employing a thin scintillator in each layer. This strategic design minimizes emitted light attenuation while simultaneously enhancing sensitivity through the cumulative effect of multiple layers. Our experiments demonstrate a significant improvement in detection efficiency compared to the single-layer setup. Additionally, our architecture offers an actual improvement in differentiating between gamma and neutron signals. By analyzing count rates across the detector’s layers, we gain valuable operational insights, such as the ability to predict the source direction. Our finding demonstrates an improved sensitivity achieved by minimal loss of neutrons during the moderation of 329% compared to a single layer, aligned with the potential range of improvement while maintaining extremely high gamma rejection. Supported by the presented findings, this design represents a noticeable advancement over existing solutions, offering scalable customization to user requirements. Notably, it outperforms traditional 3He tube-based detection configurations, positioning it as a compelling and advantageous replacement option.

Survival Rate and Esthetic Outcomes of 2-Piece Zirconia Dental Implants: A 1-Year Single Clinical Trial of Partially Edentulous Patients.

Titanium dental implants, traditionally used for tooth replacement, face certain biological and esthetic limitations. Recently, zirconia has become a notable alternative, valued for its esthetics and biocompatibility. This study evaluated the efficacy of 2-piece zirconia dental implants, particularly their impact on inflammatory cytokines and their survival rate over 1 year. This study was a single-center, prospective trial and included adults aged 18 and above. From 2021 to 2022, 9 2-piece, tissue-level zirconia implants were placed in 8 patients. Following a 3-month osseointegration phase, crowns were cemented. Over a year, we assessed plaque and gingival indices, pocket depth, and tissue color and texture. Peri-apical radiographs measured bone levels, and IL-1β in peri-implant crevicular fluid was quantified using the enzyme-linked immunosorbent assay. Eight subjects (ages 31-63) participated. One implant failed after 6 months, resulting in a 1-year survival rate of 88.8%. Plaque and gingival indices rose, but peri-implant soft tissue remained stable in color and texture. At 12 months, average bone loss was minimal and insignificant compared with the baseline, and IL-1β levels were similar to those at contralateral teeth with no correlation between IL-1β, pocket depth, and bleeding on probing. Two-piece zirconia implants emerged as a viable tooth replacement option with an 88.8% 1-year survival rate. They maintained stable soft tissue and bone levels, indicating their potential as effective dental restoratives.

Contemporary Single-Center Experience of Complete Aortic Arch Replacement Employing the Frozen Elephant Trunk Technique in Patients with Extensive Aortic Disease.

Objective: This study aimed to examine contemporary results of the frozen elephant trunk (FET) procedure in an all-comers patient cohort. Methods: Between January 2017 and May 2024, a total of 132 consecutive patients with either aortic aneurysm (n = 32), acute aortic dissection (n = 32), or chronic aortic dissection (n = 68) underwent total aortic arch replacement employing the FET technique. In-hospital data were collected prospectively and included preoperative characteristics, intraoperative data, and follow-up results. Results: The median cardiopulmonary bypass time, cardiac ischemia time, and selective antegrade cerebral perfusion time were 180 (161-205), 89 (70-113), and 45 (38-54) min, respectively. Total 30-day mortality rate was 7.6% (n = 10). The rate of major postoperative neurological complications was 6.8% (n = 9) for perioperative stroke and 2.3% (n = 3) for permanent spinal cord injury. Five patients (3.8%) required hemofiltration at the time of discharge due to postoperative kidney injury. Rates of subsequent endovascular and open aortic repair following primary FET were 40.9% (n = 54) and 3.8% (n = 5), respectively. The median time to reintervention was 86 (30-439) days. The median follow-up time was 25 (8-52) months, and overall survival rates at 1, 2, and 3 years were 89%, 89%, and 87%, respectively. Conclusions: Our data are consistent with current reports, indicating that the FET technique is a valuable adjunct in treating extensive aortic arch pathologies. The procedure provides an increasingly safe and effective option for complete aortic arch replacement, even in patients requiring a redo procedure.

Knowledge And Perception About Dental Implant And Its Complications Among GeneralPractitioners And Post Graduates In Coimbatore – A Cross Sectional Survey

Background: It is necessary for dental students and freshly graduated dentists to apply their education and practice to different clinical and preclinical procedures. The implant success rate and durability are high. Therefore, this study was designed to assess the level of knowledge, awareness and perception of dental practitioners and post graduate students regarding dental implant complications in Coimbatore. Materials and Methods: A prevalence study design using a web-based method was conducted among dental practitioners and postgraduate students in Coimbatore. Data were collected from all (n = 212) general dental practitioners and postgraduate students using a pretested standardized self-administered web-based questionnaire that was prepared and circulated using a template provided by Google Forms (Google, Inc., USA). Results: In a survey of 212 general dental practitioners and postgraduate students in Coimbatore, 69.2% considered dental implants a viable option for tooth replacement, though 38% noted financial constraints affecting patient acceptance. While 38.5% were highly aware of the risks associated with implants, 61.5% emphasized the importance of case selection. Common issues included postoperative infections (53.8%) and screw loosening (46.2%). Aesthetically, 30.8% cited loss of the interdental papilla as a concern. Most participants favored flap surgical methods (61.5%) and recommended considering patient conditions when choosing implant prostheses. Notably, 61.5% were aware of regenerative possibilities related to dental implants. Conclusion: A comprehensive evaluation concluded that undergraduate instruction in basic implantology is essential due to the increasing prevalence of implants. Additionally, postdoctoral training programs should be established to enhance practitioners' skills and knowledge, providing them with the confidence needed to treat patients effectively

A Numerical Investigation of the Influence of the Wake for Mixed Layout Wind Turbines in Wind Farms Using FLORIS

A common retrofitting method for wind farms is the replacement of low-power turbines with high-power ones. The determination of the optimal replacement sequence for the purpose of maximizing revenue is a significant challenge. This paper employs a combination of FLORIS and a sequencing algorithm to simulate the power output resulting from the replacement of 1.5 MW small turbines with 5 MW large turbines. This study demonstrates that the optimal strategy for maximizing the overall power output is to replace the turbines in the first column. When the turbines situated in the first column have already undergone replacement or are unable to be replaced due to the characteristics of the terrain, it would be prudent to prioritize those in the final column. In the case of staggered arrangements, priority should be given to diagonal points that do not have turbines situated behind them. In the case of replacing the same number of large wind turbines, the preferred replacement option has a minimal impact on the power output of the existing small wind turbines, with an estimated reduction of 0.67%. This effectively enhances the economic efficiency of wind farm renovation.

Способ улучшения зоогигиенических условий выращивания цыплят-бройлеров

Abstract. The purpose of the study is to study the effect of bedding material on the physiological parameters of broiler chickens. Since the most important condition for optimizing the microclimate in the poultry house is compliance with the physiological state of the livestock and maintaining its vital activity at an optimal level. Research methods. The experiment was carried out in the industrial conditions of a poultry farm on broiler stock of the Arbor Acres+ cross in the experimental workshop, where four sections were formed. The growth and development of broilers was monitored daily, livestock records were carried out, and a weekly veterinary report was compiled on the causes of mortality. Also, laboratory studies were carried out according to approved methods for the following indicators: ammonia content, sanitary and hygienic indicators of bedding material, volume, weight and moisture content of bedding material, as well as productivity and basic blood parameters of broiler chickens. Results. Trends in the positive effect of the sorbent in the form of modified diatomite on the productivity of broiler chickens due to the improvement of zoohygienic growing conditions have been identified. In particular, the content of the total number of microorganisms, mold spores and ammonia content in the production experimental workshop is examined in detail. During the work, the volume and weight of bedding material was calculated, including at the exit from the poultry house. We tried to pay special attention to blood biochemistry, which made it possible to assess the physiological state of broiler chickens and draw conclusions about the quality of feeding rations. At the same time, problematic issues associated with feeding poultry were identified, which affect the content of mineral elements in the blood. When determining the performance criterion, calculations were carried out using the EPEF index. Scientific novelty. For the first time, it was proven that the use of diatomite with a bulk layer height of 0.5–1 cm with a granule size of at least 5 mm as bedding material leads to improved zoohygienic conditions for raising broiler chickens without additional capital investments in the form of installation of expensive ventilation equipment or the use of additional technological operations. This replacement option has a positive effect on the health of young poultry.

Dental Anxiety Among the Individuals Referred for Implant as an Option for Replacement of Missing Teeth

Dental Anxiety Among the Individuals Referred for Implant as an Option for Replacement of Missing Teeth

The Role of a New Hinged Total Knee Arthroplasty System for Use in a Variety of Complex Knee Scenarios: A Case Series.

Hinged knee arthroplasties are commonly used in scenarios where there are major ligament deficiencies or bone loss around the knee. They are applicable in native knees with major deformities and during revisions. They can also be used as a salvage procedure after distal femoral resection. The new modular hinged device system, namely the Triathlon Hinge Knee (THK) System (Stryker, Mahwah, New Jersey), reflects the advancements of third-generation design and enhances surgical flexibility by allowing streamlined integration with the Triathlon Total Stabilized (TS) System (Stryker, Mahwah, New Jersey) and the Global Modular Replacement System (GMRS, Stryker, Mahwah, New Jersey). Additionally, the Triathlon Revision Tibial Baseplate (Stryker, Mahwah, New Jersey) has been launched as part of THK and is compatible with the Modular Rotating Hinge (MRH , Stryker, Mahwah, New Jersey) femur, which allows the Revision Baseplate to replace the existing tibial component while leaving the existing MRH Femoral Component in place. The Triathlon Revision Tibial Baseplate enables orthopaedic surgeons to use constrained or hinged prostheses, including both distal and total femoral replacement options, without changing the Tibial Baseplate. This is because the TS, MRH, THK, and GMRS femurs are compatible with the new Triathlon Revision Tibial Baseplate. Additionally, the system can be augmented with metaphyseal cone constructs to help provide a stable foundation for reconstruction. This report explores the application of a new modular hinged device system in various scenarios, starting with (1) complex primary hinged knee arthroplasty, followed by revision hinged knee arthroplasty cases including (2) failed TKA with medial collateral ligament (MCL) dysfunction, (3) severe arthrofibrosis post-TKA, (4) revisions for prosthetic joint infection, (5) extensor mechanism deficiency, and (6) arthrofibrosis with extensor mechanism disruption, concluding with a case of (7) distal femoral arthroplasty for periprosthetic fracture post-failed TKA.

The Importance of Clinical Context and Consistency in Methodology When Using Matching-Adjusted Indirect Comparisons (MAICs) to Compare Outcomes.

Hemophilia A is rare, which makes large, randomized, controlled, statistically driven, head-to-head comparison trials difficult. Matching-adjusted indirect comparisons (MAICs) are validated statistical tools designed to help make the results of non-comparative trials more comparable. The purpose of this commentary is to provide an insight into the MAIC method, in order to assist the hemophilia community with interpretation of MAIC data. It includes a comparison of the findings from previously published MAICs comparing recombinant factor replacement options and their methodologies. As MAICs are being used more often to compare treatment options for patients with hemophilia A, it is paramount that robust and consistent methodologies for cross-trial comparisons are used and that all efficacy analysis findings are linked to factor utilization.

Origin of facies-controlled dolomite and exploration significance of the Middle Permian Qixia Formation in central Sichuan Basin, Western China

The intraplatform shoal dolomite of the Middle Permian Qixia Formation is currently considered the key target of hydrocarbon exploration in the central Sichuan Basin. To systematically investigate the origin of the stratabound facies-controlled porous dolomites of the Qixia Formation, integrated petrography, logging and seismic analysis were carried out in this work. The results are as following: (1) the dolomite reservoir is universal in the central Sichuan Basin, and its distribution is controlled by intraplatform shoals, with multilayer superposition vertically. Thick massive dolostone may also develop along with the fault. (2) Three replaced dolomites and one dolomite cement were identified: very finely to finely crystalline, anhedral to subhedral dolomite (Rd1); finely to medium crystalline, anhedral to subhedral dolomite (Rd2); coarsely crystalline, subhedral to euhedral dolomite (Rd3) and coarsely crystalline saddle dolomite cement (Sd). Rd2 and Rd3 are partly fabric-retentive, and preserve the original bioclastic ghosts. Sd shows wavy extinction, filled in the breccia veins. (3) The U-Pb dating and homogenization temperatures results indicate that the dolomite and Sd cement are associated with hydrothermal event during the Emeishan large igneous province. The δ13C, 87Sr/86Sr, and seawater-like REEY patterns suggest that the dolomitization and Sd precipitation fluids originate from connate seawater heated by elevated heat-flow. (4) The ELIP triggered large scale thermal anomalies in the basin during the Dongwu movement period. The increased temperature and pressure drove the formation water in the intra-platform shoal facies and overcame the binding effect of Mg2+ hydrate. Moreover, the deep hydrothermal fluid preferentially penetrated into the porous strata of shoal facies along the faults and fractures, mixed with formation water to some extent, and extensive dolomitization occurred. The facies-controlled dolomite reservoir and the underlying Cambrian source rock form a good source-reservoir assemblage, which can be a key replacement option.

Transcatheter tricuspid valve intervention in the presence of a cardiac implantable electronic device; state of the art review.

A large proportion of patients referred for transcatheter tricuspid valve intervention (TTVI) will have the presence of a cardiac implantable electronic device (CIED). In such patients, surgical correction of tricuspid regurgitation (TR) is associated with high rates of morbidity and mortality. Transvenous lead extraction (TLE) could potentially ameliorate CIED-induced TR; however, it carries inherent risks and frequently does not result in TR improvement. As multiple TTVI devices are in trial to gain regulatory approval, understanding which therapy is most appropriate among patients with a CIED is essential. This review centers on the nonsurgical treatment, including TLE and transcatheter tricuspid valve repair and replacement options, aimed at enhancing outcomes in patients with TR who also have concurrent CIEDs.

Retrofitting homes in Ontario entails significant embodied emissions: new policies needed

ABSTRACT Emissions reduction policies and programs should consider both the operational emissions reduction from single family home retrofits and the embodied emissions of the retrofit materials. This is because it can take 0.9–10.1 years before the emissions savings from building envelope upgrades in a gas-heated home equal the embodied emissions from the materials used. The wide range reflects the range of embodied emissions for different insulation and window replacement options. Heat pumps also have significant embodied emissions from their manufacture and from refrigerant leaks, but it takes less than two and a half years of operations in Ontario to offset the emissions investment relative to heating with a gas furnace. We recommend that Canada accelerate the phase out of insulation materials with high embodied emissions and increase incentives for window replacements. Programs and policies should also consider the age of the home and the potential energy savings when recommending building envelope improvements to maximize the total emission reduction potential. Finally, heat pumps should be promoted in all homes where low carbon electricity is available because this is the simplest and most effective way to reduce carbon emissions, especially when embodied emissions are considered.

Outcomes of Colonic and Gastric Tube Transplants after Caustic Esophageal Burn in Children: A 33-Year Review.

Introduction: Accidental caustic burns of the esophagus in children represent a significant global health challenge, often necessitating esophageal reconstruction. The aim of this study is to compare the efficacy and morbidity related to esophagus replacement with colonic and gastric tube transplants in a pediatric population followed for caustic stenosis. Methods: This retrospective study was conducted at a tertiary pediatric surgery unit for children treated from January 1989 to December 2022. We compared colonic and gastric tube esophageal replacement. Short term (within 30 days) and mid-term outcomes and complications were reviewed. Statistical evaluation was considered using a Chi-square test for categorical data analysis. Results: A total of 124 children with caustic esophageal burns were included. Among them, 23 (18.5%) had a gastric tube transplant for esophagus replacement and 101 (81.5%) a colonic transplant. During surgical intervention, we found a significantly higher risk of complications when using a colonic transplant (34%, p < 0.001). There was no significant statistical difference in postoperative short term and mid-term complications between the two techniques. Twenty-six (26%) of the children required a reoperation, with a higher risk in the gastric tube transplant group (p < 0.001). Endoscopic dilatation after surgery was also performed on a higher number of children who had received a gastric tube transplant (p = 0.005). Overall, 97.6% recovered full normal oral feeding. Conclusions: We found that colonic and gastric tube replacement are both good options for pediatric esophageal replacement after a caustic injury and show effectiveness over time. Gastric tube transplants carried a slightly higher risk of reoperations and a higher number of dilatations post-surgery. However, our groups are not really comparable, due to the much higher number of colonic transplants. Both surgical options have to be considered during surgery, and the choice depends on the anatomy of the patient. Our future research will focus on assessing long term quality of life and the potential risk of neoplastic complications.

Can mechanical heart valves perform similarly to tissue valves? An in vitro study

Current surgical aortic valve (AV) replacement options include bioprosthetic and mechanical heart valves (MHVs), each with inherent limitations. Bioprosthetic valves offer superior hemodynamics but suffer from durability issues, typically initiating deterioration within 7–8 years. MHVs, while durable, necessitate lifelong anticoagulation therapy, presenting risks such as severe bleeding and thromboembolic events. The need for anticoagulants is caused by non-physiological flow through the hinge area during the closed phase and large spikes of regional backflow velocity (RBV) during the closing phase that produces high shear events. This study introduces the iValve, a novel MHV designed to combine the hemodynamic benefits of bioprosthetic valves with the durability of MHVs without requiring anticoagulation. The iValve features eye-like leaflets, a saddle-shaped housing, and an optimized hinge design to enhance blood flow and minimize thrombotic risk. Fabricated using 6061-T6 aluminum and polyether ether ketone (PEEK), twelve iValve iterations were evaluated for their opening and closing dynamics. The reported top-performing prototypes demonstrated competitive performance against industry standards. The proposed iValve prototype exhibited a mean RBV of −4.34 m/s with no spikes in RBV, performing similarly to bioprosthetic valves and significantly outperforming existing MHVs. The iValve’s optimized design showed a 7–10% reduction in closing time and a substantial decrease in RBV spikes, potentially reducing the need for anticoagulation therapy. This study highlights the iValve’s potential to revolutionize prosthetic heart valve technology by offering a durable, hemodynamically superior solution that mitigates the drawbacks of current MHVs.

Long-term complications and management of dental trauma in the adult patient - Part 2: discoloured, displaced and missing teeth.

The second paper in this two-part review series aims to outline the long-term complications of dental trauma in the adult patient in relation to discoloured, displaced or missing teeth. A brief overview of the cause of discolouration is outlined, followed by assessment and management options. These can include bleaching, veneers, or crown restorations to mask the discolouration. Displacement of teeth from the socket can occur due to luxation injuries. Management can include simple digital manipulation, surgical repositioning, or orthodontic extrusion based on the severity of extrusion and the time from injury. Teeth can be lost early or in the long-term following dental trauma and associated hard and soft tissues deficiencies may also ensue. Replacement options can include a removable partial prosthesis, resin-retained bridge or dental implants. Often, hard and soft tissue augmentation procedures may be required to address any defects and rebuild lost anatomical contours. A thorough assessment followed by the development of a sound management plan which takes patients' general and local factors into account can ensure a predictable and successful treatment outcome. This would end in an aesthetically pleasing and a functionally stable result for the patient.

Potential of an Amphiphilic Artificial Corneal Endothelial Layer as a Replacement Option for Damaged Corneal Endothelium.

Bullous keratopathy, a condition severely impacting vision and potentially leading to corneal blindness, necessitates corneal transplantation. However, the shortage of donor corneas and complex surgical procedures drive the exploration of tissue-engineered corneal endothelial layers. This study develops a transparent, amphiphilic, and cell-free membrane for corneal endothelial replacement. The membrane, securely attached to the posterior surface of the cornea, is created by mixing hydroxyethyl methacrylate (HEMA) and ethylene glycol dimethylacrylate (EGDMA) in a 10:1 ratio. A 50µL volume is used to obtain a 60µm hydrophobic membrane on both sides, with one side treated with a polyvinylpyrrolidone (PVP) solution. The resulting membrane is transparent, foldable, biocompatible, amphiphilic, and easily handled. When exposed to 20% sulfur hexafluoride (SF6), the hydrophilic side of the membrane adheres tightly to the corneal Descemet's membrane, preventing water absorption into the corneal stroma, and thus treating bullous keratopathy. Histological test confirms its effectiveness, showing normal corneal structure and low inflammation when implanted in rabbits for up to 100 d. This study showcases the potential of this membrane as a viable option for corneal endothelial replacement, offering a novel approach to address donor tissue scarcity in corneal transplantation.