Bone Research Articles

A Single-Cell RNA Sequencing Guided Multienzymatic Hydrogel Design for Self-Regenerative Repair in Diabetic Mandibular Defects.

Conventional bone tissue engineering materials struggle to reinstate physiological bone remodeling in a diabetic context, primarily due to the compromised repolarization of proinflammatory macrophages to anti-inflammatory macrophages. Here, leveraging single-cell RNA sequencing (scRNA-seq) technology, the pivotal role of nitric oxide (NO) and reactive oxygen species (ROS) is unveiled in impeding macrophage repolarization during physiological bone remodeling amidst diabetes. Guided by scRNA-seq analysis, we engineer a multienzymatic bone tissue engineering hydrogel scaffold (MEBTHS) composed is engineered of methylpropenylated gelatin hydrogel integrated with ruthenium nanozymes, possessing both Ru0 and Ru4+ components. This design facilitates efficient NO elimination via Ru0 while simultaneously exhibiting ROS scavenging properties through Ru4+. Consequently, MEBTHS orchestrates macrophage reprogramming by neutralizing ROS and reversing NO-mediated mitochondrial metabolism, thereby rejuvenating bone marrow-derived mesenchymal stem cells and endothelial cells within diabetic mandibular defects, producing newly formed bone with quality comparable to that of normal bone. The scRNA-seq guided multienzymatic hydrogel design fosters the restoration of self-regenerative repair, marking a significant advancement in bone tissue engineering.

Plasma SQSTM1/p62 act as a biomarker for steroid-induced osteonecrosis of the femoral head

Autophagy is closely associated with the onset and progression of steroid-induced osteonecrosis of the femoral head (SIONFH). SQSTM1/p62 is an important indicator of autophagic activity. The aim of this study was to investigate the role of SQSTM1/p62 in the development of SIONFH. From May 2021 through November 2021, 36 patients diagnosed with SIONFH and 36 healthy controls were recruited for this study. Evaluations included imaging and pathologic assessment of clinical bone tissue, location and level of SQSTM1/p62 expression, plasma SQSTM1/p62 levels, and receiver operating characteristic (ROC) curves. We observed that the expression level of SQSTM1/p62 in bone samples decreased with the Association Research Circulation Osseous (ARCO) phase. Plasma SQSTM1/p62 levels were significantly higher in the SIONFH group compared to healthy controls. Plasma SQSTM1/p62 levels were higher in pre-crash patients than in post-crash patients, and lower plasma SQSTM1/p62 levels were associated with elevated ARCO stage. Plasma SQSTM1/p62 may represent a potential biomarker for different stages during SIONFH. Lower plasma SQSTM1/p62 levels indicate an advanced stage of SIONFH. This study provides new clues for early diagnosis of SIONFH.

Anticonvulsants impacting bone metabolism: interim results from a cross-sectional study

Background. Despite a wide range of antiepileptic drugs (AEDs) with an improved pharmacological profile, patients often experience a variety of side effects during long-trem anticonvulsant therapy, among which are osteoporotic disorders. Currently, the mechanisms of AED effect on bone metabolism remain poorly understood, which creates certain difficulties in prevention and treatment of AED-induced osteoporosis.Objective: to study bone mineral density and laboratory parameters of bone metabolism in patients with epilepsy and longterm AED administration.Material and methods. A cross-sectional study included two comparison groups: 100 adult patients with epilepsy receiving AEDs for more than 12 months and 58 healthy volunteers without taking AEDs. All participants underwent general clinical examination, computed tomography (CT) densitometry at three time points (L1, L2 and femoral neck) and laboratory tests of mineral metabolism.Results. According to CT-densitometry results, a decrease in bone mineral density was detected in the majority of participants from both study groups. While assessing an impact of osteoporosis risk factors on bone tissue in epileptic patients, low motor activity and duration of AED therapy were the most significant, which was associated with lower bone mineral density indices. The study of laboratory mineral metabolism indicators revealed significant inter-group differences in indicators such as ionized calcium, 25-hydroxy-calciferol, free thyroxine and prolactin (p(U)=0.044, p(U)=0.040, p(U)=0.001, p(U)=0.003, respectively).Conclusion. The intermediate study results showed that long-term anticonvulsant use negatively affected bone metabolism in patients suffering from epilepsy. The data obtained point at need for further in-depth study of AED therapy effect on mineral metabolism.

Mechanical and Corrosion Behaviour in Simulated Body Fluid of As-Fabricated 3D Porous L-PBF 316L Stainless Steel Structures for Biomedical Implants.

Laser powder bed fusion (L-PBF) is one of the most promising additive manufacturing technologies for creating customised 316L Stainless Steel (SS) implants with biomimetic characteristics, controlled porosity, and optimal structural and functional properties. However, the behaviour of as-fabricated 3D 316L SS structures without any surface finishing in environments that simulate body fluids remains largely unknown. To address this knowledge gap, the present study investigates the surface characteristics, the internal porosity, the corrosion in simulated body fluid (SBF), and the mechanical properties of as-fabricated 316L SS structures manufactured by L-PBF with rhombitruncated cuboctahedron (RTCO) unit cells with two distinct relative densities (10 and 35%). The microstructural analysis confirmed that the RTCO structure has a pure austenitic phase with a roughness of ~20 µm and a fine cellular morphology. The micro-CT revealed the presence of keyholes and a lack of fusion pores in both RTCO structures. Despite the difference in the internal porosity, the mechanical properties of both structures remain within the range of bone tissue and in line with the Gibson and Ashby model. Additionally, the as-fabricated RTCO structures demonstrated passive corrosion behaviour in the SBF solution. Thus, as-fabricated porous structures are promising biomaterials for implants due to their suitable surface roughness, mechanical properties, and corrosion resistance, facilitating bone tissue growth.

Accelerated Frostbite-Induced Acroosteolysis in Pediatric Insensate Hand: A Case Report and Literature Review.

In pediatric patients, frostbite is a well-documented cause of epiphyseal cartilage destruction and subsequent growth deformity of the affected phalanges. Cases of full acroosteolysis, also referred to as phalangeal osteolysis, of distal phalanges as soon as three months after cold exposure have yet to be reported. We describe a complicated case of frostbite-associated phalangeal osteolysis in the dominant hand of a nine-year-old patient, in the context of post-traumatic insensate hand after sustaining prior electrical burn injuries. This case demonstrates the unique sequela of pediatric frostbite injury involving early loss of the distal phalanx through resorption of the bone and parallel soft tissue retraction, rendering early plastic surgery reconstruction impractical. Reconstructive strategies for frostbite injury in pediatric patients will need to account for the individualized dynamic tissue changes that develop in the months after cold exposure.

Does Injectable Platelet-Rich Fibrin Combined With Autogenous Demineralized Dentine Enhance Alveolar Ridge Preservation? A Randomized Controlled Trial.

The present trial evaluated the first-time application of autogenous demineralized dentin graft with injectable platelet-rich fibrin (ADDG + i-PRF) versus autogenous demineralized dentin graft (ADDG), in alveolar ridge preservation (ARP) in the maxillary aesthetic zone. Twenty-two maxillary (n = 22) non-molar teeth indicated for extraction were randomized into two groups (n = 11/group). Extracted teeth were prepared into ADDG, implanted into extraction sockets with or without i-PRF amalgamation and covered by collagen sponge. Cone-beam computed tomography scans at baseline and 6 months were compared to assess ridge-dimensional changes. Keratinized tissue width, patient satisfaction, pain score and chair time were recorded. In the course of dental implant placements at 6 months, bone core biopsies of engrafted sites were obtained and analysed histomorphometrically. Reduction in ridge width was 1.71 ± 1.08 and 1.8 ± 1.35 mm, while reduction in ridge height was 1.11 ± 0.76 and 1.8 ± 0.96 mm for ADDG + i-PRF and ADDG, respectively (p > 0.05). Significant differences in keratinized tissue width reduction were notable between ADDG + i-PRF and ADDG (0.12 ± 0.34 and 0.58 ± 0.34 mm respectively; p = 0.008). Postoperative pain scores were significantly lower in ADDG + i-PRF (p = 0.012). All patients in the two groups were satisfied with no differences in chair time (p > 0.05). No differences in total percentage area of newly formed bone, soft tissue or graft particles were observed between the groups (p > 0.05). ADDG alone or in combination with i-PRF yields similar results regarding ARP clinically, quality of the formed osseous tissues, as well as patients' satisfaction. Yet, the addition of i-PRF to ADDG tends to preserve the keratinized tissue and lessen postoperative pain.

Bone microstructure analyses in ontogenetic series of Mesosaurus tenuidens from the early Permian of Brazil.

Osteohistological evidence is widely used to infer paleobiological traits of fossil vertebrates, such as ontogeny and growth rates. Mesosaurs, an enigmatic group of aquatic reptiles from the early Permian, are the most well-known Paleozoic amniotes from Africa and South America. Their fossils are abundant in South America, ranging from the central-west region of Brazil to the southernmost areas, as well as parts of Paraguay and Uruguay. In this contribution, we examined the bone microstructure of Mesosaurus tenuidens by analyzing thin sections of axial and appendicular elements of several specimens collected from various Brazilian sites. The microstructure of the bones showed minimal histological variability among elements, predominantly composed of parallel-fibered tissues, indicating slow growth rhythm, along with increased bone density attributed to pachyosteosclerosis. The cortical area consists of poorly vascularized parallel-fibered bone tissue, which was interrupted by multiple cyclical growth marks, some of them being supernumerary, suggesting a strong influence of seasonality. Moreover, the organization of growth marks suggests distinct life history trajectories among individuals collected from different outcrops, reflecting environmental heterogeneity throughout the basin. Internally, the endosteal domain exhibits greater vascularization compared to the cortices and frequently contained calcified cartilage. In the ontogenetic series, there was a progressive filling of the medullary region from small to large individuals. The presence of the External Fundamental System (a proxy indicating somatic maturity) was observed in femora and ribs, suggesting that determinate growth was already occurring in Permian mesosaurs and may not be an exclusive specialization of crown amniotes.

A New Era of Tooth Preparation and Gingitage Retraction Technique: A Case Report

The demand for procedures intended to improve dental aesthetics has increased recently. Preserving the teeth and surrounding soft structures to the greatest extent possible is preferred in this situation by both patients and dentists. When using fixed prostheses, maintaining the stability and health of soft tissues is a constant struggle. Bone tissue health and soft tissue health are directly correlated. The long-term efficacy of prosthetic therapy thus depends on preserving tissue health and being free of mucositis. This case report describes the successful application of the gingitage technique in a patient requiring aesthetic enhancement of the gingival margins surrounding dental restorations. The patient presented with uneven gingival contours and mild inflammation around subgingival margins of existing restorations, compromising both function and aesthetics. Results demonstrated significant improvements in gingival health, a more balanced gingival margin, and an enhanced aesthetic outcome. Follow-up assessments revealed stable gingival contours and an overall increase in patient satisfaction. This case report underscores the effectiveness of the gingitage technique as a minimally invasive solution for enhancing soft tissue aesthetics and supporting the longevity of dental restorations.

Treatment of patients with periprosthetic infection and management of Paprosky type 2C cavitary defects at the stage of articulating spacer installation

Introduction Due to the constant increase in the number of primary and revision hip arthroplasties, the incidence of complications has been also increasing. Periprosthetic joint infection (PJI) is the most common and dangerous complication in joint arthroplasty, including PJI with cavitary defects of the acetabulum (Paprosky type 2C).The purpose of the work was to demonstrate successful results of managing acetabular defects in patients with periprosthetic infection at the stage of installing an articulating spacer.Materials and methods The patients underwent surgical management of cavitary defects of the acetabulum with allobone plastic material at the stage of installation of an articulating spacer impregnated with antibacterial drugs. A clinical and functional assessment of the effectiveness of treatment of patients with PJI of the hip joint, who underwent bone grafting of acetabular defects at the first stage of two-stage revision arthroplasty, was carried out. Remission of the infectious process was assessed according to the ICM 2013 (International Consensus Meeting), and the function of the affected limb was assessed according to the HHS (Harris Hip Score).Results At a 6-month follow-up after implantation, there were no clinical and laboratory manifestations of PJI and radiological signs of instability of the implant components. Bone grafting was evaluated to be satisfactory; the function of the affected joint restored to 80–90 to HHS points. Remission of the infectious process according to ICM was achieved.Discussion Clinical cases studied demonstrate a positive result of treatin PJI with plastic surgery of cavitary defects of the acetabular bottom at the stage of articulating spacer installation. Filling acetabular defects at the sanitizing stage (implantation of a spacer) subsequently provides improvement of primary fixation and osseointegration of the acetabular component when converting the spacer to a permanent implant. This is due to an increase in the contact area of the acetabular component with bone tissue (native bone and remodeled allobone material).Conclusion The treatment of the first clinical case improved joint function from 24 to 85 HHS points, and in the second from 27 to 76 HHS points. The use of defect filling techniques enabled to stop the infection and improve functional results.

Amputation and limb-sparing surgery in childhood sarcoma: Post-operative imaging appearances and complications.

Limb-sparing surgery and amputation are common surgical techniques used to achieve local tumour control in childhood primary bone and soft tissue malignancy of the limbs. The interpretation of post-operative limb imaging in these frequently complex cases is assisted by knowledge of the surgical techniques employed. This review discusses the rationale underpinning the most common surgical techniques used for these patients as well as their expected post-operative imaging appearance and complications. Amputation, long bone resection, endoprosthetic reconstruction, allograft reconstruction, the use of fibular autografts, allograft-prosthetic composite reconstruction and arthrodesis are discussed.

Optimizing revision arthroplasty: the role of customized articulating spacers

Introduction The advancement of surgery is set against a backdrop of continuous development and surgical innovations have transformed the way clinical care is delivered. Revision surgery might be required to address complications of primary arthroplasty. The first stage of revision arthroplasty would involve removal of an implant and placement of an antibiotic-impregnated cement spacer to maintain the joint space and stability, prevent soft tissue retraction, provide local antibiotic release and preserve bone tissue for revision implantation at the final stage of revision. Custom-made articulating spacers are a promising tool for optimizing the first stage of revision arthroplasty.The objective was to summarize the current data and present comprehensive information about spacers used in two-stage revision arthroplasty including manufacturing techniques, physical and chemical properties, clinical applications, the possibility of customization within the first stage of revision arthroplasty, current and promising directions for research.Material and methods The original literature search was conducted on key resources including Scientific Electronic Library (www.elibrary.ru), the National Library of Medicine (www.pubmed.org), the Cochraine Library (www.cochranelibrary.com) between 2018 and 2023 using search words and phrases: total arthroplasty, complications, revision arthroplasty, articulating spacer, periprosthetic joint infection, additive manufacturing, 3D printing.Results A comparative analysis of factory supplied, home-made, dynamic and static spacer models showed that the choice of articulating spacers for revision arthroplasty of major joints is of great relevance. Advantages of factory-made spacers include standardized range of sizes, the reliability and availability for medical institutions. They are characterized by limited use in repair of severe bone defects.Discussion Custom-made articulating spacers enable specific tailoring to accommodate individual defects. Despite high expectations from custom-made spacers, development of optimal technologies for rapid prototyping is essential. Investments in research and development in this area have the potential to create innovative solutions that can significantly improve the results of revision arthroplasty.Conclusion The paper explores the importance of systemization of knowledge about spacers and the role of new research in improving the design and functionality. Progress in the field of materials science, additive technologies and a personalized approach to spacer manufacturing can expand possibilities of revision arthroplasty and the effectiveness. Personalized approaches and improved methods of local drug delivery that provide controlled release of antibiotics can improve the results of treatment of periprosthetic joint infections.

Application of lactoferrin for the prevention and restoration of bone tissue in Wistar rats under conditions of hindlimb unloading

The influence of gravitational unloading (antiorthostatic suspension) and subsequent recovery on the mineral density and mechanical properties of the femoral and tibial bones of Wistar rats was studied with oral administration of a biotechnological analog of human lactoferrin (200 mg/kg) derived from the milk of producer goats. Bone mineral density was determined by dual-energy X-ray absorptiometry, and strength and stiffness were assessed through three-point bending tests. It was shown that gravitational unloading for 21 days led to a decrease in the mineral density of the tibial and femoral bones. The administration of lactoferrin did not significantly affect the mineral density or projected area of the studied bones. No statistically significant differences in mechanical stiffness were found between the experimental groups, but after readaptation, the ultimate strength was significantly higher in the groups that received lactoferrin. Thus, the obtained results may indicate the potential of lactoferrin preparations as prophylactic agents for maintaining bone strength. At the same time, maintaining bone mineral density under deficit-stimulating conditions requires consideration of alternative dosages and delivery methods of the drug.

3D-BIOPRINTING OF BONE TISSUE IN VITRO И IN SITU

Advanced techniques in bone tissue regeneration include innovative achievements in the field of tissue engineering, among which 3D bioprinting technology holds a special place. This method demonstrates significant progress, driven by its numerous advantages, confirmed through extensive scientific research. 3D bioprinting offers the capability of precise printing of bone transplants with specified geometry, incorporating necessary biomaterials such as cells and growth factors, which facilitates effective osteoinduction, osteoconduction, and vascularization. This review article analyzes various modern methods of bone tissue restoration, including the use of autotransplants, allotransplants, and synthetic bone transplants. Particular attention is paid to the latest innovations in 3D bioprinting, opening prospects for creating individualized bone tissues characterized by a high degree of biocompatibility and minimizing the need for invasive procedures. Additionally, the article presents the concept of in situ bioprinting, developed by Weiss and his colleagues in 2007, as a method of direct printing of bio-inks directly in the area of damage in a living organism. This progressive approach provides high precision in the restoration of tissue defects, regardless of their complexity and geometric features. Over the last decade, several successful clinical cases of using printed structures have been registered, demonstrating the significance of 3D bioprinting in treating life-threatening diseases, as well as in accelerating the regeneration process and creating tissue transplants for subsequent implantation.

Expression of osteopontin and osteocalcin in Osteoblast cells exposed to a combination of polymethylmethacrylate (PMMA) and hydroxyapatite (HAp): A prospective observational study.

The success of implant placement will depend on the ability of the implant material to integrate with the surrounding tissue. Polymethylmethacrylate (PMMA) has been used as an implant material, but it has several fallback properties in its interaction with bone tissue. The addition of hydroxyapatite (HAp) to PMMA is expected to produce reinforced bioceramic polymers with better mechanical and biological properties. The purpose of this study was to evaluate the expression of osteopontin and osteocalcin in cultured osteoblasts when exposed to two implant candidate materials: PMMA-HApGMP, derived from bovine bone and processed under Good Manufacturing Practice by a Tissue Bank, and PMMA-HApBBK, sourced from limestone (CaCO3) and processed by Balai Besar Keramik. Twenty-four fetal rat calvariae osteoblast cell cultures were randomly divided into 6 groups: 7- and 14-day control group, 7 and 14 days PMMA-HApGMP group, 7 and 14 days PMMA-HApBBK group. The expression of osteopontin and osteocalcin was seen by immunocytochemical examination. The results showed that the average expression of osteopontin and osteocalcin in the treatment group on the 7th and 14th days was higher than the control group. The expression of osteopontin and osteocalcin in the PMMA-HApGMP group increased significantly (P < .05) on day 14. The PMMA-HAp combination material can accelerate the process of osteoblast differentiation which is characterized by an increase in osteopontin and osteocalcin which are markers of bone formation. This will support in increasing osseointegration.

Mapping RANKL- and OPG-expressing cells in bone tissue: the bone surface cells as activators of osteoclastogenesis and promoters of the denosumab rebound effect.

Denosumab is a monoclonal anti-RANKL antibody that inhibits bone resorption, increases bone mass, and reduces fracture risk. Denosumab discontinuation causes an extensive wave of rebound resorption, but the cellular mechanisms remain poorly characterized. We utilized in situ hybridization (ISH) as a direct approach to identify the cells that activate osteoclastogenesis through the RANKL/OPG pathway. ISH was performed across species, skeletal sites, and following recombinant OPG (OPG:Fc) and parathyroid hormone 1-34 (PTH) treatment of mice. OPG:Fc treatment in mice induced an increased expression of RANKL mRNA mainly in trabecular, but not endocortical bone surface cells. Additionally, a decreased expression of OPG mRNA was detected in bone surface cells and osteocytes of both compartments. A similar but more pronounced effect on RANKL and OPG expression was seen one hour after PTH treatment. These findings suggest that bone surface cells and osteocytes conjointly regulate the activation of osteoclastogenesis, and that OPG:Fc treatment induces a local accumulation of osteoclastogenic activation sites, ready to recruit and activate osteoclasts upon treatment discontinuation. Analysis of publicly available single-cell RNA sequencing (scRNAseq) data from murine bone marrow stromal cells revealed that Tnfsf11+ cells expressed high levels of Mmp13, Limch1, and Wif1, confirming their osteoprogenitor status. ISH confirmed co-expression of Mmp13 and Tnfsf11 in bone surface cells of both vehicle- and OPG:Fc-treated mice. Under physiological conditions of human/mouse bone, RANKL is expressed mainly by osteoprogenitors proximate to the osteoclasts, while OPG is expressed mainly by osteocytes and bone-forming osteoblasts.

Exploring the Impact of Catechins on Bone Metabolism: A Comprehensive Review of Current Research and Future Directions.

Background/Objectives: Degenerative musculoskeletal diseases represent a global health problem due to the progressive deterioration of affected individuals. As a bioactive compound, catechins have shown osteoprotective properties by stimulating osteoblastic cells and inhibiting bone resorption. Thus, this review aimed to address the mechanism of action of catechins on bone tissue. Methods: The search was applied to PubMed without limitations in date, language, or article type. Fifteen articles matched the topic and objective of this review. Results: EGCG (epigallocatechin gallate) and epicatechin demonstrated action on the osteogenic markers RANKL, TRAP, and NF-κβ and expression of BMPs and ALP, thus improving the bone microarchitecture. Studies on animals showed the action of EGCG in increasing calcium and osteoprotegerin levels, in addition to regulating the transcription factor NF-ATc1 associated with osteoclastogenesis. However, it did not show any effect on osteocalcin and RANK. Regarding human studies, EGCG reduced the risk of fracture in a dose-dependent manner. In periodontal tissue, EGCG reduced IL-6, TNF, and RANKL in vitro and in vivo. Human studies showed a reduction in periodontal pockets, gingival index, and clinical attachment level. The action of EGCG on membranes and hydrogels showed biocompatible and osteoinductive properties on the microenvironment of bone tissue by stimulating the expression of osteogenic growth factors and increasing osteocalcin and alkaline phosphate levels, thus promoting new bone formation. Conclusions: EGCG stimulates cytokines related to osteogenes, increasing bone mineral density, reducing osteoclastogenesis factors, and showing great potential as a therapeutic strategy for reducing the risk of bone fractures.

Clinical Outcomes of Scapular versus Fibular free flaps in Head and Neck Reconstructions: A Retrospective Study of 120 patients".

The scapular free flap has increasingly gained popularity as an alternative to the fibular free flap in osseous head and neck reconstruction. The present study aimed to evaluate their use in maxillomandibular reconstructions and examine surgical and patient outcomes. Osseous head and neck defects reconstructed with an angular artery-based scapular flap or fibular flap from 2016 to 2022 at two Swedish University Hospitals were evaluated for their intraoperative execution (osseous and soft tissue combinations) and postoperative outcomes. Facial quality of life (QoL) was assessed using the FACEQ Head and Neck Cancer Module. Donor-site morbidity was assessed using the DASH and SEFAS questionnaires for scapular- and fibular-reconstructed patients, respectively. A total of 120 patients were recruited: 86 mandibular reconstructions (26 scapulas, 60 fibulas) and 34 maxillary reconstructions (32 scapulas, 2 fibulas). The concave scapula facilitated fewer osteotomies for curved reconstructions, particularly for lateral mandibular defects (p=0.039). Intraoral lining was primarily achieved with muscle accompanying the scapula and skin accompanying the fibula. Using the latissimus dorsi muscle instead of only teres major decreased fistulas, plate/bone exposure and non-unions (p=0.039) in scapular reconstructions. Both flaps demonstrated comparable facial QoL, but the scapula presented superior donor site outcomes (p=0.001). Donor limb outcomes were unaffected by harvesting the latissimus dorsi with the scapula (p=0.64), and by re-suturing the detached muscles to the remaining scapula. (p=0.35). The scapular free flap can be advantageous in osseous head and neck reconstructions, enabling non-osteotomized and chimeric reconstructions without compromising surgical outcomes or quality of life.

Triad of female athletes

The female sports triad is a spectrum of dysfunctions related to energy availability, menstrual function, and bone mineral density. Energy availability is considered the trigger for the triad. Scientists have proven that women who do sports consume approximately 30% less energy and carbohydrates in relation to their body weight. Sufficient energy availability ensures the presence of a menstrual cycle, directly affects the stimulation of the production of female sex hormones (estrogen in particular). Thus, it prevents resorption of bone tissue. When energy availability is too low, a physiological mechanism reduces the amount of energy used for cell maintenance, thermoregulation, growth, and reproductive function. This compensation tends to restore energy balance and promotes survival, but impairs health. Low body weight in women of reproductive age, particularly in adolescence and the first reproductive age, is a biological marker of somatic and reproductive dysfunction. Osteoporosis in young female athletes is manifested by fractures unusual for young women or by frequent and multiple bone fractures during an athletic career. In this review article, an analytical review of literary and informational sources regarding the history of research on the problem of the triad of female athletes is carried out. The specifics of the negative impact of the athlete triad on the female body, the components of the athlete triad (amenorrhea, eating disorders, and osteoporosis) are examined in detail. The article focuses on its main cause - energy imbalance. The impact of the triad of female athletes on the psyche and behavior is considered. The question of its consequences for health both in the short-term and in the long-term perspective is considered. The prevention of RED-S syndrome was also investigated. The purpose of the study: Systematization of current knowledge about the triad of female athletes (relative energy deficiency syndrome (RED-S)). Research methods. Theoretical analysis of literary sources, systematization, generalization of scientific-methodical and special literature.

Perda precoce dos elementos 11 e 12 por trauma dental, com intervenção ortodôntica preventiva na odontopediatria: relato de caso

Dental trauma is one that affects the hard tissues embraced, supporting structures or soft tissues in the oral cavity. It is observed more frequently in male children of school age (07 to 12 years old). The most affected teeth in the trauma taken are central and lateral incisors. With regard to tooth avulsions, the protection of children's bone tissue favors a higher frequency in this population than in the adult population. Dental avulsion occurs after displacement of the element out of its alveolus. There is a break in the blood supply to the pulp of the tooth and when this happens the chance of replantation achieved is totally impossible. Thus bringing several harms to the patient such as difficulty in speech, poor aesthetics, or even mesialize or distalize some other acquired element. Space maintainers are used as removable or fixed appliances to treat malocclusion or esthetic defects. They are braces made of acrylics with two extended teeth. Choosing a removable appliance comes with benefits such as better hygiene, satisfactory aesthetics, low cost, and maintenance of the cervico-occlusal space, in addition to the mesio-distal space. The objective of this study was to report a clinical case of avulsion of element 11 and 12 caused by trauma in childhood with the use of a space maintainer. We conclude that it is possible to treat a patient with dentoalveolar trauma with intervention using a space maintainer, since in the present case success was obtained in the selection of therapy, restoring aesthetics and function to the patient. Thus reducing possible orthodontic problems of the child, with follow-up until his/her old age.

Optimizing surgical approaches for lacrimal gland adenoid cystic carcinoma to minimize cross-organ invasion.

To evaluate the outcomes of eye-sparing surgery for lacrimal gland adenoid cystic carcinoma and the impact on tumor recurrence and orbital integrity. The study enrolled four patients with recurrent lacrimal gland adenoid cystic carcinoma. The outcome focused on the relevance of the integrity of the lateral orbital wall to the occurrence of extraorbital metastasis in the local recurrence of lacrimal gland adenoid cystic carcinoma. Three patients underwent eye-sparing surgery via lateral orbitotomy without postoperative radiotherapy, and one patient who underwent eye-sparing surgery via sub-brow approach. These four patients all demonstrated a recurrence involving the invasion of extraorbital tissues as metastatic form through surgical bone seams. Preserving intact orbital bone tissue is crucial for mitigating direct cross-organ metastasis of lacrimal gland adenoid cystic carcinoma. The findings suggest avoiding the lateral orbitotomy approach with no or limited orbital bone wall invasion.