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Background: Given the popularity of pterional craniotomy, numerous modifications have been made to prevent postoperative deformities. With the advent of titanium plates, fixation has become both simple and excellent. However, titanium plates can cause skin problems, infection, or cause skull growth to fail. Methods: To develop a simple, cost-effective, and esthetically satisfactory fixation method, without the use of non-metallic materials, six young and older patients underwent pterional craniotomy. CranioFix Absorbable clamps were used to fix the bone flap in the frontal and temporal regions such that the frontal part was in close contact with the skull. After fixation, the bone chips and bone dust were placed in the bone gap and fixed with fibrin glue. We measured the computed tomography values of the reconstructed area and thickness of the temporal profiles postoperatively over time. Results: Bone fusion was achieved in all patients by 1 year after surgery. Both the thickness of the temporalis muscle and the thickness of the temporal profile had changed within 2 mm as compared with the preoperative state. Conclusion: Our simple craniotomy technique, gentle tissue handling, and osteoplastic cranioplasty yielded satisfactory esthetic results and rigidness in pterional craniotomy.

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Cytobrushes are used for low-invasive sample collection and screening in multiple diseases, with a significant impact on early detection, prevention, and diagnosis. This study focuses on improving the safety of cell brushing in hard-to-reach locations by exploring brush construction from absorbable materials. We investigated the efficacy of loop brushes made of absorbable suture wires of Chirlac, Chirasorb, Monocryl, PDS II, Vicryl Rapid, Glycolon, and Catgut during their operation in conjunction with fine-needle aspiration in an artificial cyst model. PDS II brushes demonstrated the highest efficiency, while Monocryl and Catgut also provided a significant brushing effect. Efficient brushes portrayed higher flexural rigidity than their counterparts, and their efficiency was inversely proportional to their plastic deformation by the needle. Our results open avenues for safer cell biopsies in hard-to-reach locations by utilizing brushes composed of absorbable materials.

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As one of the long-established and necessary medical devices, surgical sutures play an essentially important role in the closing and healing of damaged tissues and organs postoperatively. The recent advances in multiple disciplines, like materials science, engineering technology, and biomedicine, have facilitated the generation of various innovative surgical sutures with humanization and multi-functionalization. For instance, the application of numerous absorbable materials is assuredly a marvelous progression in terms of surgical sutures. Moreover, some fantastic results from recent laboratory research cannot be ignored either, ranging from the fiber generation to the suture structure, as well as the suture modification, functionalization, and even intellectualization. In this review, the suture materials, including natural or synthetic polymers, absorbable or non-absorbable polymers, and metal materials, were first introduced, and then their advantages and disadvantages were summarized. Then we introduced and discussed various fiber fabrication strategies for the production of surgical sutures. Noticeably, advanced nanofiber generation strategies were highlighted. This review further summarized a wide and diverse variety of suture structures and further discussed their different features. After that, we covered the advanced design and development of surgical sutures with multiple functionalizations, which mainly included surface coating technologies and direct drug-loading technologies. Meanwhile, the review highlighted some smart and intelligent sutures that can monitor the wound status in a real-time manner and provide on-demand therapies accordingly. Furthermore, some representative commercial sutures were also introduced and summarized. At the end of this review, we discussed the challenges and future prospects in the field of surgical sutures in depth. This review aims to provide a meaningful reference and guidance for the future design and fabrication of innovative surgical sutures. STATEMENT OF SIGNIFICANCE: This review article introduces the recent advances of surgical sutures, including material selection, fiber morphology, suture structure and construction, as well as suture modification, functionalization, and even intellectualization. Importantly, some innovative strategies for the construction of multifunctional sutures with predetermined biological properties are highlighted. Moreover, some important commercial suture products are systematically summarized and compared. This review also discusses the challenges and future prospects of advanced sutures in a deep manner. In all, this review is expected to arouse great interest from a broad group of readers in the fields of multifunctional biomaterials and regenerative medicine.

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This study aimed to investigate the appropriate size of scaffold implantation on stress distribution and evaluate its mechanical and biomechanical properties considering hydrolysis. The meniscus acts as a load distribution in the knee, and its biomechanical properties are essential for the development of the PGA scaffold. We established a novel meniscal scaffold, which consists of polyglycolic acid (PGA) covered with L-lactide-ε-caprolactone copolymer (P[LA/CL]). After 4 weeks of hydrolysis, the scaffold had a 7% volume reduction compared to the initial volume. In biomechanical tests, the implantation of scaffolds 20% larger than the circumferential and vertical defect size results in greater contact stress than the intact meniscus. In the mechanical evaluation associated with the decomposition behavior, the strength decreased after 4 weeks of hydrolysis. Meanwhile, in the biomechanical test considering hydrolysis, contact stress and area equivalent to intact were obtained after 4 weeks of hydrolysis. In conclusion, the implantation of the PGA scaffold might be a useful alternative to partial meniscectomy in terms of mechanical properties, and the PGA scaffold should be implanted up to 20% of the defect size.

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Lacrimal plug is an effective and widely therapeutic strategy to treat dry eye. However, almost all commercialized plugs are fixed in a certain design and associated with many complications, such as spontaneous plug extrusion, epiphora, and granuloma and cannot be traced in the long-term. Herein, a simple in situ forming hydrogel is developed as a tracer and degradable lacrimal plug to achieve the best match with the irregular lacrimal passages. In this strategy, methacrylate-modified silk fibroin (SFMA) is served as a network, and a self-assembled indocyanine green fluorescence tracer nanoparticle (FTN) is embedded as an indicator to develop the hydrogel plug using visible photo-crosslinking. This SFMA/FTN hydrogel plug has excellent biocompatibility and biodegradability, which can be noninvasively monitored by near-infrared light. In vivo tests based on dry eye rabbits show that the SFMA/FTN hydrogel plug can completely block the lacrimal passages and greatly improve the various clinical indicators of dry eye. These results demonstrate that the SFMA/FTN hydrogel is suitable as an injectable and degradable lacrimal plug with a long-term tracking function. The work offers a new approach to the development of absorbable plugs for the treatment of dry eye.

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The development of crack patterns is a serious problem affecting the durability of orthopedic implants and the prognosis of patients. This issue has gained considerable attention in the medical community in recent years. This literature focuses on the five primary aspects relevant to the evaluation of the surface cracking patterns, i.e., inappropriate use, design flaws, inconsistent elastic modulus, allergic reaction, poor compatibility, and anti-corrosiveness. The hope is that increased understanding will open doors to optimize fabrication for biomedical applications. The latest technological issues and potential capabilities of implants that combine absorbable materials and shape memory alloys are also discussed. This article will act as a roadmap to be employed in the realm of orthopedic. Fatigue crack growth and the challenges associated with materials must be recognized to help make new implant technologies viable for wider clinical adoption. This review presents a summary of recent findings on the fatigue mechanisms and fracture of implant in the initial period after surgery. We propose solutions to common problems. The recognition of essential complications and technical problems related to various approaches and material choices while satisfying clinical requirements is crucial. Additional investigation will be needed to surmount these challenges and reduce the likelihood of fatigue crack growth after implantation.

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Tough double network (DN) hydrogels are promising substitutes of soft supporting tissues such as cartilage and ligaments. For such applications, it is indispensable to robustly fix the hydrogels to bones with medically feasible methods. Recently, robustly bonding the DN hydrogels to defected bones of rabbits in vivo has been proved successful. The low crystalline hydroxyapatite (HAp) of calcium-phosphate-hydroxide salt coated on the surface layer of the DN hydrogels induced spontaneous osteogenesis penetrating into the semi-permeable hydrogels to form a gel/bone composite layer. In this work, the 44 Ca isotope-doped HAp/DN hydrogel is implanted in a defect of rabbit femoral bone and the dynamic osteogenesis process at the gel/bone interface is analyzed by tracing the calcium isotope ratio using isotope microscopy. The synthetic HAp hybridized on the surface layer of DN gel dissolves rapidly in the first two weeks by inflammation, and then the immature bone with a gradient structure starts to form in the gel region, reutilizing the dissolved Ca ions. These results reveal, for the first time, that synthetic HAp is reutilized for osteogenesis. These facts help to understand the lifetime of bone absorbable materials and to elucidate the mechanism of spontaneous, non-toxic, but strong fixation of hydrogels to bones.

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INTRODUCTION: Absorbable materials have been used as fixation devices in orthopaedic surgery. However, their use for treating isolated ulnar diaphyseal fractures in adults has not yet been studied. The aim of this study was to assess whether Inion OTPS™ absorbable implants consisting of L-lactide, D, L-lactide, and trimethylene carbonate provide adequate fixation for the healing of isolated ulnar diaphyseal fractures, their complication rate, and the patients' clinical functional outcome. MATERIALS AND METHODS: Three consecutive patients (all women; mean age, 45 years, and range 38-55 years) with isolated, unstable ulnar fractures were enrolled and treated operatively using Inion OTPS™ absorbable plates and screws. Discontinuation of the study was decided because of the early failure of all implants. The patients were assessed clinically (DASH Score and grip strength) and radiographically at 6 weeks, 3 months, 6 months, and 9 months. The incidence of late foreign body reactions was evaluated for 10 years follow-up period. RESULTS: Implant failure was noticed radiographically in the early post-operative period in all three patients. Subsequently, one patient was treated operatively using metallic devices, and the other two with prolonged splinting. All fractures healed uneventfully in variable time frames. No foreign body reactions were noticed during and beyond the degradation period, other than a small painless mass in one case. CONCLUSION: The results of the current study suggest that the Inion OTPS™ plating system is not appropriate for the fixation of isolated unstable ulnar diaphyseal fractures. It seems that these specific implants cannot withstand the internal mechanical forces of this anatomical area despite the protective splinting.

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During the last two decades, biodegradable/absorbable materials which have many benefits over conventional implants are being sought in clinical practices. However, to date, it still remains obscure for us to perform full physic-chemical characterization and biological risk assessment for these materials and related devices due to their complex design and coherent processing. In this review, based on the art of knowledge for biodegradable/absorbable materials and biological risk assessment, we demonstrated some promising strategies to establish and improve the current biological evaluation systems for these biodegradable/absorbable materials and related medical devices.

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Objective To evaluate the surgical approaches, surgical timing and materials for cranial defect repair in children. Methods From the year 2002 to 2006, 4 children with cranial defect received cranial reconstruction using absorbable poly-L-lactic acid (PLA) material and hydroxyapatite. Results The 3-year follow-up showed that the cranial defect was successfully repaired using the absorbable material in 3 patients and failure of repair occurred in 1 patient. Conclusion Cranial defect in children can be effectively repaired using absorbable materials and hydroxyapatite without obviously affecting the skull development. This approach provides an important option for cranial defect repair in children.