BACKGROUND: Myomodulation is a technique aimed at enhancing the dynamics of muscle contraction and relaxation through methods like hyaluronic acid (HA) injection. Achieving optimal outcomes depends on the precise placement of the injected product within the targeted anatomical plane. This is particularly important in the forehead, an area with elevated vascular risk. The selected treatment techniques must ensure both efficacy and safety. This study aims to assess the anatomical precision of HA injections in the forehead using different techniques and devices.
METHODS: Four fresh frozen specimens were injected with HA by five experienced board-certified plastic surgeons using three different techniques/devices: (1) a 50 mm, 22G microcannula; (2) a 13 mm, 27G needle with the bevel down at a 45-degree angle; and (3) the same needle positioned at a 90-degree angle. Ultrasound analysis was used to evaluate the precision of each approach.
RESULTS: Both the cannula technique and the needle technique with the bevel down at a 45-degree angle consistently delivered the filler to the supraperiosteal layer in 100% of cases without spreading. However, the 90-degree needle technique, despite correct placement on the periosteum, resulted in filler dispersion across multiple layers.
CONCLUSIONS: The accuracy of filler placement in the forehead is influenced by the choice of device and its angulation. It is recommended to use a cannula with the entry point at the frontalis crest or a needle angled at 45 degrees to the skin. The use of a needle at a 90-degree angle should be avoided to ensure precise placement and avoid filler migration.
METHODS: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors   www.springer.com/00266 .

Patient demand for procedures has increased in the evolving landscape of cosmetic dermatology. This has been fueled, in part, by social media and the growing normalization of cosmetic enhancements; however, this has led some patients to have potentially unrealistic expectations, placing undue pressure on dermatologists to meet these often unrealizable demands. This pressure is further exacerbated by patients who are seen as difficult, demanding, and time-consuming and who may require extensive counseling. Physicians may adopt dynamic or differential pricing strategies to offset the additional time and effort these patients require. We discuss the ethical concerns surrounding these pricing strategies in the cosmetic sphere, highlight the importance of transparency in pricing, and offer suggestions to promote clarity and fairness in cosmetic dermatology practices.

BACKGROUND: Hyaluronidase remains the mainstay treatment for skin necrosis due to vascular occlusion after hyaluronic acid (HA) dermal fillers. There is wide variability in protocols for the administration of hyaluronidase. Most protocols, however, lack strong evidence regarding hyaluronidase dosages.
METHODS: We conducted a systematic review and pilot meta-analysis, searching four international databases from inception until December 2023 for clinical studies reporting on two or more patients receiving hyaluronidase for skin necrosis after hyaluronic acid fillers. Random-effects (DerSimonian and Laird) meta-analyses were conducted. The primary outcome was the pooled proportion of complete scar resolution. We rated intra-study risk of bias using the Joanna Briggs Institute checklists and assessed the certainty of evidence using the GRADE approach.
RESULTS: We included 15 studies totaling 223 patients. The pooled proportion of complete scar resolution after hyaluronidase administration was 77.8% (95%-CI: 65.5% to 86.6%, pegger = 0.093, low certainty). Patients treated with high doses of hyaluronidase (>500 international units [IUs]) had lower rates of resolution of 69.6% (95%-CI: 41.2% to 88.3%) compared to those treated with low doses (500IU or less) that had 88.1% rate of resolution (95%-CI: 86.0% to 96.2%), though not statistically significant (p= 0.18). The use of adjunct therapies did not have a statistically significant effect on outcomes.
CONCLUSIONS: A higher proportion of patients receiving low doses (500IU or less) (88.1%) had complete scar resolution compared to patients receiving high doses (69.7%), though not statistically significant (p=0.18). Future studies should provide more granular details on their protocols to benefit the formulation of evidence-based guidelines in future.
METHODS: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
BACKGROUND: CRD42024538661.

The utilization of steel slag as an alternative material in asphalt mixtures is considered the solution to the problem of the shortage of natural aggregates. However, asphalt mixtures with steel slag show susceptibility to damage caused by moisture, especially in powder form. Therefore, blast furnace slag powders were used to compound with steel slag powders as fillers to improve the moisture resistance of asphalt mixtures. The characteristics of the steel slag powders and blast furnace slag powders were investigated initially. Subsequently, the adhesion properties of the asphalt mastics with the powders to the aggregates were evaluated. Finally, the moisture resistances of the asphalt mixtures were identified. The results indicate that the steel slag powder exhibited a notable prevalence of surface pores, which had a more uniform size distribution. In contrast, the blast furnace slag powder exhibited a greater average pore size. The larger specific surface area of the steel slag powder was over 30% larger than that of the blast furnace slag powder, and the superior gelling activity of the blast furnace powder enhanced the adhesion property. Both the steel slag powder and blast furnace slag powder were found to enhance the adhesion properties of the asphalt mastics, while the effect of the steel slag powder was more pronounced, the maximum force difference of which exceeded 200 N. The antagonistic effect of the steel slag powder and blast furnace slag powder on the resistance of the adhesive interface to moisture damage was confirmed by the contact angle test. The incorporation of the blast furnace slag powder markedly enhanced the moisture resistances of the asphalt mixtures. The phenomenon of dynamic moisture damage to the asphalt mixtures was more pronounced under the multicycle times, obviously severer than that in a stable water environment. As the dynamic moisture cycles increased, the degree of destruction gradually approached a steady state.

Knowledge of anatomy not only allows optimal treatment and therefore full satisfaction of our patients, but is also fundamental in the prevention of complications. A thorough understanding of aging allows for effective treatments, as most patients demand a natural result, removing the inevitable signs of aging, which can only be understood by considering their aging. Facial aging is a natural but complex multifactorial process, particularly for the forehead. In this article, we will focus on botulinum toxin as well as fillers in aging.

This review article will discuss the origin of resin-based dental composite materials and their adoption as potentially useful adjuncts to the primary material used by most dentists for direct restorations. The evolution of the materials, largely driven by the industry\'s response to the needs of dentists, has produced materials that are esthetic, strong, and versatile enough to be used in most areas of the oral cavity to replace or restore missing tooth structures. Significant advancements, such as the transition from chemical to light-curing materials, refinements in reinforcing particles to produce optimum polishing and wear resistance, formulating pastes with altered viscosities to create highly flowable and highly stiff materials, and creating materials with enhanced depth of cure to facilitate placement, will be highlighted. Future advancements will likely reflect the movement away from simply being a biocompatible material to one that is designed to produce some type of beneficial effect upon interaction within the oral environment. These new materials have been called \"bioactive\" by virtue of their potential effects on bacterial biofilms and their ability to promote mineralization of adjacent tooth structures.

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The performance of natural rubber (NR), a naturally occurring and sustainable material, can be greatly enhanced by adding different fillers to the NR matrix. The homogeneous dispersion of fillers in the NR matrix is a key factor in their ability to reinforce. As a novel method, wet mixing technology may effectively provide good filler dispersion in the NR matrix while overcoming the drawbacks of conventional dry mixing. This study examines the literature on wet mixing fillers, such as graphene, carbon nanotubes, silica, carbon black, and others, to prepare natural rubber composites. It also focuses on the wet preparation techniques and key characteristics of these fillers. Furthermore, the mechanism of filler reinforcement is also examined. To give guidance for the future development of wet mixing technology, this study also highlights the shortcomings of the current system and the urgent need to address them.

The creation of polymer composite materials by compositing fillers into polymer materials is an effective method of improving the properties of polymer materials, and the development of new fillers and their novel composite methods is expected to lead to the creation of new polymer composite materials. In this study, we develop a new filler material made of low-molecular-weight gelators by applying a gelation process that simultaneously performs the swelling (gelation) of crosslinked polymer materials and the self-assembly of low-molecular-weight gelators into low-dimensional crystals in organic solvents within polymer materials. The gelation process of crosslinking rubber-based polymers using alkylhydrazides/toluene as the low-molecular-weight gelator allowed us to composite self-assembled sheet-like crystals of alkylhydrazides as fillers in polymeric materials, as suggested by various microscopic observations, including infrared absorption measurements, small-angle X-ray diffraction measurements and thermal analysis, microscopy, and infrared absorption measurements. Furthermore, tensile tests of the composite materials demonstrated that the presence of fillers improved both the Young\'s modulus and the tensile strength, as well as the elongation at yield. Additionally, heat treatment was shown to facilitate filler dispersion and enhance the mechanical properties. The findings demonstrate the potential of self-assembled sheet-like crystals of low-molecular-weight gelators as novel filler materials for polymers. The study\'s composite method utilizing gelators via gelation proved effective.

High-temperature polymers are attractive for applications in extreme temperatures, where they maintain their mechanical flexibility and electrical insulating properties. However, their heat dissipation capability is limited due to their intrinsically low thermal conductivities. Hexagonal boron nitride (hBN) is a chemically inert, thermally stable, and electrically insulative compound with a high thermal conductivity, making it an ideal candidate as a filler within a high-temperature polymer matrix to increase the thermal conductivity. This study evaluates the effect of filler size and dispersion on thermal conductivity by producing homogeneous composite samples using a combination of solvent mixing and resonant acoustic mixing (RAM). We carefully characterized our samples, including the spread of the size distribution, and observed that the smaller sized hBN centered around 5 μm was able to integrate more seamlessly into the polytetrafluoroethylene (PTFE) matrix with particle size in the 15 μm range and hence outperformed 30 μm, in contrast to the conventional wisdom, which asserts that larger fillers universally perform better than smaller ones. Our thermal conductivity of hBN/PTFE composites at 30 wt % is 2× higher than the literature values. Notably, we reached the record-high value of 3.5 W/m K at 40 wt % with an onset of percolation at 20 wt %, attributed to optimized hBN dispersion that facilitates the formation of thermal percolation. Our findings provide general guidelines to enhance the thermal conductivity of polymer composites for thermal management, ranging from power transmission to microelectronics cooling.