Journal of long-term effects of medical implants最新文献

Two-piece implants unavoidably present a microgap between the implant and the abutment interface. Although numerous modalities have been attempted to overcome this situation, the implant abutment interface still remains a critical point for microbial colonization, which starts an inflammatory cascade of events eventually compromising the implants. Throughout our life, cells in all biological systems are unprotected to oxidative stress leading to the formation of Reactive oxygen species which is of concern when it comes to placing implants in patients who are periodontally compromised. This necessitates the development of alternative therapeutic modalities, which could counteract as well as prevent the microbial overload and ROS generation thereby improving the longevity of implants. To evaluate and assess the antibacterial, antioxidant and anti inflammatory effectiveness of quercetin-loaded titanium nanocomposites as coatings over healing abutments. Quercetin-loaded titanium nanocomposites were synthesized using green synthesis and confirmation was done using UV spectroscopy. Healing abutments were coated with the formulated nanocomposites, an intra-oral environment was simulated by thermocycling. Their antibacterial, antioxidant, anti-inflammatory, and cytotoxicity were assessed using standard tests. Healing abutments were coated with the formulated nanocomposites, an intra-oral environment was simulated by thermocycling. They showed potent antibacterial, antioxidant, and anti-inflammatory properties, which could prove beneficial in a variety of clinical scenarios in which there is a high risk for implant failure during early osseointegration.

To describe an in-office minimal approach technique for closing recently operated full thickness macular holes (FTMH), when closure was not fully achieved or there was macular hole re-formation, without performing another pars plana vitrectomy (PPV). Retrospective case series study. Nine patients were included in this case series. All patients were diagnosed with FTMH characterized by a decrease in visual acuity (VA) and metamorphopsias. All patients initially underwent a standard PPV procedure with 20% sulfur hexafluoride (SF6) injection. After 1-16 weeks, no closure or reformation of the macular hole was observed. Fluid-SF6 exchange was performed in the slit lamp, with the aim of injecting a 50% gas bubble of pure SF6 into the vitreous cavity, according to a minimally invasive in-office technique. Postoperatively, all patients achieved successful macular hole closure and VA showed an average improvement of approximately 4 lines on the EDTRS logarithm of the minimum angle of resolution (logMAR) chart. In particular, the mean corrected distance visual acuity improved from 0.99 ± 0.27 logMAR to 0.33 ± 0.23 logMAR (P = 0.03). The minimal surgical in-office technique of SF6 injection for the management of reopened macular holes after a recent PPV procedure shows promising results.

Introduction: Masseter muscle is considered to consist of two layers: the superficial and the deep parts. However, in the literature a few cases have been reported of a third layer of the masseter muscle, which is called the coronoid part. The aim of this study is to present such a rare case of the coronoid part of the masseter muscle.

Material and methods: In our study, a case report is presented and enhanced by searching the existing literature in PubMed for other similar cases that recorded the coronoid part of the masseter muscle.

Results: The coronoid part of the masseter muscle was found in a male cadaver of Greek origin that was dissected in the Department of Anatomy, Medical School Athens, Greece.

Conclusions: Good knowledge of anatomy and variations of the masseter muscle are of paramount importance due to their clinical and functional applications as well as during surgical procedures in this anatomical region.

The application of stainless-steel wire is still the "standard of care" and is believed to be the "gold standard" after trans-sternal thoracotomy. To overcome postoperative instability and surgical wound infection there had been the development of a variety of circumferential, Hemi-circular, and surface on-lay implant designs to enhance bone healing of the sternum particularly in compromised patients. This fundamental descriptive theoretical research study probes into biology and effects of mechanical environment on fracture healing in general and various types of ossifications that may occur during healing of the sternum. Following surgical anatomy of the sternum, the biology of fracture (osteotomy) healing, an update on the conventional and newer biomaterials, and role of 3D printing in custom additive manufacturing of the surgical implants have been discussed in detail. There is discussion on design principles and structural optimization in-line with patient-specific and patient-appropriate osteosynthesis. In support, the Teorija Rezhenija Izobretatelskikh Zadatch engineering principles have been applied to improve implant design in the face of the current strategies to relieve some of the recalcitrant deficiencies underlying the mechanics of the most favored implant for the reconstruction of the sternum. Several scientific domains of the engineering design principles and fracture healing processes have been connected leading to four newly conceptualized prototype designs for the reconstruction of the sternum. In conclusion, despite increased knowledge of the fracture healing process there are limited means to mitigate the adverse mechanical environment experienced by the healing sternum. There are uncertainties how to transfer the well-known facts of tissue strain during healing from the experimental platform to the operating table at the time of fracture fixation and reconstruction of the sternum for its optimal healing.

Pathological fractures of the proximal radius are exceedingly rare. Here, a case of an 81-year-old female diagnosed with multiple myeloma 15 years ago who suffered a pathological fracture of her left proximal radius is presented. Due to the fracture's proximity to the elbow joint and the lack of adjacent healthy bone tissue, a resourceful surgical intervention was implemented using a pediatric flexible nail supplemented by polymethacrylate cement injection. Six weeks post-operatively, the patient had alleviation of the pain with fully functional forearm. This novel approach could possibly aid in the treatment of other long bone pathological fractures due to neoplastic metastases.

Hip osteoarthritis (OA), or the degeneration of cartilage in the hip joint, is a common and chronic condition that is growing in prevalence around the world. OA typically causes significant joint pain, lack of mobility, and abnormal gait patterns in affected individuals. Total hip arthroplasty (THA) is used to treat OA, and of the many postoperative methods of assessing success of the procedure, one that is particularly useful is gait analysis. Gait analysis provides a quantitative view of patient gait biomechanics by examining many relevant gait parameters and is very useful to evaluate sequelae following THA. The present paper synthesizes the recent literature surrounding post-THA gait analysis to gain a deeper understanding of how gait analysis may be used to improve THA and its corresponding patient outcomes.

Orthopedic implants are crucial interventions that are gaining greater importance in modern medicine to restore function to commonly affected joints. Each implantation carries the risk of implant-associated infection and loosening of the implant due to improper integration with soft tissue. Coating strategies have been developed to aid the growth of bone into the implant (osteointegration) and prevent biofilm formation to avoid infection. In this review, primary articles highlighting recent developments and advancements in orthopedic implant coating will be presented. Additionally, the methodology of the articles will be critiqued based on this research criteria: establishment of function on a theoretical basis, validation of coating function, and potential next steps/improvements based on results. A theoretical basis based on understanding the mechanisms at play of these various coatings allows for systems to be developed to tackle the tasks of osteointegration, subversion of infection, and avoidance of cytotoxicity. The current state of research methodology in coating design focuses too heavily on either osteointegration or the prevention of infection, thus, future development in medical implant coating needs to investigate the creation of a coating that accomplishes both tasks. Additionally, next steps and improvements to systems need to be better highlighted to move forward when problems arise within a system. Research currently showcasing new coatings is performed primarily in vitro and in vivo. More clinical trials need to be performed to highlight long-term sustainability, the structural integrity, and the safety of the implant.

The implant survival largely depends on the mechanical setting in which they work as an independent entity. The implant design, number and position markedly affect the treatment plan. Deficient bone quantity and quality and presence of a vital anatomical landmark have often led the practitioners to conduct researches to find newer ways of implant insertion. One such technique is the 'All-On-4' concept, an alternative to the conventional implant therapy; lessens the amount of strain to the alveolar bone by increasing the antero-posterior spread with distal tilting the posterior implant. It is a cost-effective procedure that decreases the treatment time and the morbidity rate allowing a higher patient quality of life. The article demonstrates clinical cases describing rehabilitation of completely edentulous arches using the All-On-4 concept.

To compare the Vickers microhardness, surface roughness, initial adhesion, and osteogenic differentiation on titanium (Ti) and nitrurized titanium (NTi) plates were treated by UV irradiation and chitosan. Each plate was subjected to Vickers hardness with a pressure of 2.9 N for 10 seconds and roughness evaluation by atomic force microscope (AFM) analysis. Three groups of each type of plates were tested: control (C), ultraviolet irradiation (UV), and chitosan (Q). The UV group was exposed to UV-irradiation for 20 min at 253.7 nm (52 μW/cm2). The Q group was coated with 1% chitosan, and the C group had no treatment. The osteoblasts (2 × 106 cells/mL) were inoculated in each group for 60 min and their viability was determined by the MTT bioassay. Osteogenic differentiation was performed over 4 weeks and determined by alizarin red staining. The mean was analyzed with the Shapiro-Wilks, Kruskall-Wallis, and Mann-Whitney U tests of normality (n = 9/gp). The NTi plates hardness (125.1 ± 4.01 HV) was higher (P = 0.026) than the Ti plates (121.3 ± 2.23 HV). The surface topography was: NTi (Ra = 0.098 μm) and Ti (Ra = 0.212 μm). The quantification of cell adhesion was: Ti + Q = 123 ± 4.9% (P < 0.05) < NTi + Q = 107 ± 3.3% < Ti = 100 ± 10.7% < NTi = 72 ± 6.8% < NTi + UV = 71 ± 4.4% < Ti + UV = 69 ± 3.5%, regardless the plates, the presence of chitosan induce a faster osteogenic differentiation. The Ti + Q plates tested the highest cell attachment and osteogenic adhesion suggesting their potential use of chitosan for cell-implant interaction.

This systematic review assesses the microbiological similarities and differences between healthy and diseased peri-implant sulci based on available literature evidence. A thorough electronic search was conducted in databases such as PubMed, Google Scholar, and Cochrane; a manual search employing eligibility criteria was conducted as well. After a comprehensive review, studies evaluating the microbial profile obtained from biofilm samples from healthy and diseased peri-implant sulci were chosen. Ten articles compared microbial profiles of healthy and failing implants. A statistically significant variation in the microbial profile was observed, with predominating Gram-negative, anaerobic organisms at both the genus and species level between healthy and diseased peri-implant sulci. Also, red complex organisms (P. gingivalis, T. forsythia, and P. intermedia) predominated in diseased peri-implant sulci. According to existing studies, peri-implantitis is characterized by a diverse microbial community that includes obligate anaerobic Gram-negative bacteria such as T. denticola, T. forsythia, P. gingivalis, and P. intermedia. This research will pave the way for further studies assessing specific bacterial flora in diseased peri-implant sulci, which will help in developing specific treatment targets for peri-implantitis.