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Journal of Plastic, Reconstructive &... Aug 2014Hypertrophic scars and keloids can be aesthetically displeasing and lead to severe psychosocial impairment. Many invasive and non-invasive options are available for the... (Review)
Review
Hypertrophic scars and keloids can be aesthetically displeasing and lead to severe psychosocial impairment. Many invasive and non-invasive options are available for the plastic (and any other) surgeon both to prevent and to treat abnormal scar formation. Recently, an updated set of practical evidence-based guidelines for the management of hypertrophic scars and keloids was developed by an international group of 24 experts from a wide range of specialities. An initial set of strategies to minimize the risk of scar formation is applicable to all types of scars and is indicated before, during and immediately after surgery. In addition to optimal surgical management, this includes measures to reduce skin tension, and to provide taping, hydration and ultraviolet (UV) protection of the early scar tissue. Silicone sheeting or gel is universally considered as the first-line prophylactic and treatment option for hypertrophic scars and keloids. The efficacy and safety of this gold-standard, non-invasive therapy has been demonstrated in many clinical studies. Other (more specialized) scar treatment options are available for high-risk patients and/or scars. Pressure garments may be indicated for more widespread scarring, especially after burns. At a later stage, more invasive or surgical procedures may be necessary for the correction of permanent unaesthetic scars and can be combined with adjuvant measures to achieve optimal outcomes. The choice of scar management measures for a particular patient should be based on the newly updated evidence-based recommendations taking individual patient and wound characteristics into consideration.
Topics: Adrenal Cortex Hormones; Cicatrix, Hypertrophic; Compression Bandages; Cryotherapy; Humans; Injections, Intralesional; Keloid; Laser Therapy; Postoperative Complications; Practice Guidelines as Topic; Silicones; Skin Transplantation; Tissue Expansion
PubMed: 24888226
DOI: 10.1016/j.bjps.2014.04.011 -
International Journal of Cosmetic... Oct 2022Nowadays, the use of silicones in cosmetic formulation is still controversial, given that "natural" or "biodegradable" components are preferred. Often, the exclusion...
OBJECTIVE
Nowadays, the use of silicones in cosmetic formulation is still controversial, given that "natural" or "biodegradable" components are preferred. Often, the exclusion and/or the discrimination of these excipients from cosmetic field are unmotivated because all things cannot be painted with the same brush. Hence, we want to bring to light and underline the advantages of including silicones in cosmetic emulsions, refuting and debunking some myths related to their use.
METHODS
Silicone-free and silicone-based emulsions were obtained within an easy homogenization process. Droplet size distribution was assessed by laser diffraction particle size analyser Mastersizer 2000™, and by optical microscopy. The long-time stability profiles were investigated thanks to the optical analyser Turbiscan® Lab Expert. Diffusing wave spectroscopy (DWS) by Rheolaser Master™ and frequency sweep measurements by Kinexus® Pro Rotational Rheometer were carried out to assess a full rheological characterization. In vivo studies were carried out by the evaluation of Trans Epidermal Water Loss (TEWL) over time on healthy human volunteers. A skin feeling rating was collected from the same volunteers by questionnaire.
RESULTS
From size distribution analysis, a better coherence of data appeared for silicone-based emulsion, as the size of the droplets was kept unchanged after 1 month, as well as the uniformity parameter. Morphological investigation confirmed a homogenous droplet distribution for both samples. Silicones enhanced the viscosity, compactness and strength of the cream, providing a suitable stability profile both at room temperature and when heated at 40°C. The solid-like viscoelastic behaviour was assessed in the presence of dynamic oscillatory stresses. The monitoring of TEWL over time demonstrated non-occlusive properties of emulsions containing silicones, the values of which were comparable to the negative control. Silicone-based emulsions gained higher scores from the volunteers in silkiness, freshness and softness features, while lower scores were obtained in greasiness compared to silicone-free emulsions. No cases of irritation were recorded by the candidates.
CONCLUSION
The presence of specific silicones inside a cosmetic product improved its technological characteristics. The rheological identity and the stability feature showed the real suitability of prepared emulsion as a cosmetic product. Moreover, this study demonstrated that silicone-based emulsions are safe for the skin and did not cause skin occlusion. Improved skin sensations are registered by potential consumers when silicones are included in the formulation.
Topics: Cosmetics; Emulsions; Humans; Rheology; Silicones; Skin; Water
PubMed: 35815903
DOI: 10.1111/ics.12800 -
Clinical and Experimental Dental... Jun 2019Zinc oxide eugenol (ZOE) has traditionally been used as a root filling material in primary teeth pulpectomy. Calcium hydroxide and iodoform (Ca(OH)/iodoform) may have... (Comparative Study)
Comparative Study Meta-Analysis
Zinc oxide eugenol (ZOE) has traditionally been used as a root filling material in primary teeth pulpectomy. Calcium hydroxide and iodoform (Ca(OH)/iodoform) may have advantages as a root canal filling material to evaluate treatment success of Ca(OH)/iodoform pulpectomy in primary teeth compared with ZOE based on clinical and radiographical criteria. All human clinical studies reporting clinical and radiographical outcomes of Ca(OH)iodoform compared with ZOE in primary teeth pulpectomy were identified in digital bibliographic databases. Two authors independently selected studies and extracted relevant study characteristics. Success of treatment was based on an accomplishment of specific clinical and radiographical criteria. Meta-analyses were performed to appraise study heterogeneity and aggregated statistics. Out of 5,000 articles identified in initial search, 15 articles met all inclusion criteria, while 10 were included in the meta-analyses. At 6- and 12-month follow-up, there were no statistically significant differences in the clinical and radiographical success rates of Ca(OH)/iodoform and ZOE. However, ZOE was shown to have statistically significant higher success rates at ≥18-month follow-up. On the basis of the findings of this systematic review, we recommend that Ca(OH)/iodoform be utilized for pulpectomy in primary teeth nearing exfoliation; conversely, ZOE should be utilized when exfoliation is not expected to occur soon. Future randomized control clinical trials with a long-term follow-up are needed before a reliable conclusion can be drawn as to the best pulpectomy material. The success of pulpectomy in primary teeth depends on selecting the ideal root canal filling material. It is challenging to select the appropriate filling materials for primary teeth. ZOE or ZOE/iodoform combined with Ca(OH) appears to be the materials of choice if primary teeth are not nearing exfoliation. More high-quality randomized control clinical trials with a long-term follow-up period are needed before a reliable conclusion can be drawn as to the best pulpectomy material in primary teeth (systematic review registration number: CRD42016037563).
Topics: Calcium Hydroxide; Humans; Pulpectomy; Root Canal Filling Materials; Silicones; Tooth, Deciduous; Zinc Oxide-Eugenol Cement
PubMed: 31249711
DOI: 10.1002/cre2.173 -
Journal of Biomedical Materials... Aug 2022Contact lenses are one of the most successful biomaterials in history with a global market estimated to be worth over $17 billion in 2025. Silicone hydrogel contact...
Contact lenses are one of the most successful biomaterials in history with a global market estimated to be worth over $17 billion in 2025. Silicone hydrogel contact lenses dominate the market and are complex biphasic biomaterials with several critical material properties needed for clinical use. Careful consideration of composition and chemistry is needed to identify formulations of lenses meeting all commercial standards with the potential for improved manufacturability, cost, and/or next generation use. Four silicone macromers were investigated in this work with varying symmetry of siloxane units and macromer structure, number of siloxane groups, branching, length, and concentration. Novel silicone hydrogel lenses were produced and evaluated for optical transmittance, elastic modulus, oxygen transmissibility, water content, and surface wettability. Several lenses met commercial standards and demonstrated an increase in oxygen permeability (Dk) and inverse relationship with elastic modulus and siloxane concentration, respectively. A hydrophobic/hydrophilic ratio below 1.4 was needed for a co-continuous water phase. Substitution of methoxypropyl groups for butyl groups increased hydrophobic microdomains leading to decreased optical quality and mechanical properties. Generally, fluorine-containing silicone macromers allowed for a wider range of successful compositions, and above a certain hydrophilic composition, the presence of trifluoropropyl groups resulted in improved solubility and optically clear lenses. Data also showed asymmetric siloxane macromers have potential to meet critical lens properties at lower overall siloxane content. New lens materials with wider composition ranges meeting all clinical lens properties is a significant challenge and may significantly expand the field.
Topics: Biocompatible Materials; Contact Lenses; Hydrogel, Polyethylene Glycol Dimethacrylate; Hydrogels; Oxygen; Silicones; Siloxanes; Water
PubMed: 35366061
DOI: 10.1002/jbm.a.37389 -
Journal of Biomedical Optics Feb 2022Tissue-like solid phantoms with identical optical properties, known within tolerant uncertainty, are of crucial importance in diffuse optics for instrumentation...
SIGNIFICANCE
Tissue-like solid phantoms with identical optical properties, known within tolerant uncertainty, are of crucial importance in diffuse optics for instrumentation assessment, interlaboratory comparison studies, industrial standards, and multicentric clinical trials.
AIM
The reproducibility in fabrication of homogeneous solid phantoms is focused based on spectra measurements by instrument comparisons grounded on the time-resolved diffuse optics.
APPROACH
Epoxy-resin and silicone phantoms are considered as matrices and both employ three different instruments for time-resolved diffuse spectroscopy within the spectral range of 540 to 1100 nm. In particular, we fabricated two batches of five phantoms each in epoxy resin and silicone. Then, we evaluated the intra- and interbatch variability with respect to the instrument precision, by considering the coefficient of variation (CV) of absorption and reduced scattering coefficients.
RESULTS
We observed a similar precision for the three instruments, within 2% for repeated measurements on the same phantom. For epoxy-resin phantoms, the intra- and the interbatch variability reached the instrument precision limit, demonstrating a very good phantom reproducibility. For the silicone phantoms, we observed larger values for intra- and interbatch variability. In particular, at worst, for reduced scattering coefficient interbatch CV was about 5%.
CONCLUSIONS
Results suggest that the fabrication of solid phantoms, especially considering epoxy-resin matrix, is highly reproducible, even if they come from different batch fabrications and are measured using different instruments.
Topics: Optics and Photonics; Phantoms, Imaging; Reproducibility of Results; Silicones; Spectrum Analysis
PubMed: 35112513
DOI: 10.1117/1.JBO.27.7.074713 -
Journal of Otolaryngology - Head & Neck... Sep 2022Full thickness skin grafting is a common technique for reconstructing defects in the head and neck area. We propose the use of an addition-cured silicone as an...
BACKGROUND
Full thickness skin grafting is a common technique for reconstructing defects in the head and neck area. We propose the use of an addition-cured silicone as an individually moulded silicone dressing to keep the vulnerable skin graft in place, prevent shearing forces and create a moist environment.
METHOD
The silicone dressing is applied directly on the graft, using a double cartridge system. The silicone is moulded to the skin graft and hardens quickly, integrating thread knots into its material and creating good adherence to the graft. Charts of 24 patients who had undergone reconstruction with full thickness skin graft from the neck after surgery for skin tumors in the head from November 2017 to October 2020, were reviewed retrospectively to quantify the degree of post-operative graft loss and durability of the dressing.
CONCLUSION
Medical silicone based on venylpolysiloxane is a safe and durable dressing which makes postoperative dressing changes expendable. Trial registration The study was approved by the institutional review board of the Brandenburg state medical association (S 4(bB)/2021).
Topics: Bandages; Deafness; Humans; Retrospective Studies; Silicones; Skin Transplantation
PubMed: 36104790
DOI: 10.1186/s40463-022-00577-7 -
Scientific Reports Feb 2021Previous studies have reported silicone oil (SO) applied to needles and syringes in the vitreous of patients after intravitreal injections. We evaluated four syringes...
Previous studies have reported silicone oil (SO) applied to needles and syringes in the vitreous of patients after intravitreal injections. We evaluated four syringes (SR 1-mL insulin, Saldanha-Rodrigues; BD 1-mL Tuberculin Slip Tip, Becton-Dickinson; BD Ultra-Fine 0.3 mL, HSW Norm-Ject Tuberculin, Henke Sass Wolf) and 10 needles (BD PrecisionGlide 27- and 30-gauge (G); BD Eclipse and JBP Nanoneedle 27-, 30-, 33- and 34-G; TSK Invisible Needle and 27 and 30-G Steriject Control Hub). The protein-free buffer samples injected into the syringes and needles under study were collected in an Eppendorf tube and taken to Flow imaging microscopy, that characterized the concentration and morphology of the microsized particles. The number of particles was analyzed. The coefficients of variation (CV) were the primary outcome. The Feltz and Miller test compared the CVs. The significance level was 5%. Numerous particles and high CVs were associated with both devices, needles and syringes; the comparisons among them did not reach significance. The BD Ultrafine 0.3 mL syringe (149.7%) had the highest CV and the SO-free HSW Norm-Ject (66.4%) syringe the lowest, and the TSK Invisible needle (149.5%) had the highest and the BD Precision Glide 30G needle (35.9%) needle the lowest. In conclusion, particle release, including those with SO morphology, varied greatly among instruments, even from the same lots, which is relevant considering that fewer particles are injected into some eyes compared with others.
Topics: Needles; Reproducibility of Results; Silicon; Silicone Oils; Syringes
PubMed: 33633285
DOI: 10.1038/s41598-021-84158-0 -
Medical Engineering & Physics Sep 2022External gloves for anthropomorphic prosthetic hands protect the mechanisms from damage and ingress of contaminants and can be used to create a pleasing, life-like...
External gloves for anthropomorphic prosthetic hands protect the mechanisms from damage and ingress of contaminants and can be used to create a pleasing, life-like appearance. The properties of the glove material are the result of a compromise between the resistance to damage and flexibility. Silicone gloves are easier to flex and keep clean, but also more easily damaged. This paper details the use of nanoclay fillers to enhance the properties of silicone, successfully increasing strength whilst maintaining flexibility. The performance of the enhanced silicone is as robust and resistant to tear and puncture as commercial gloves, while being more flexible. This flexibility makes the incorporation of a piezo-electric pressure sensor based on the EEonyx conductive fabric, practical. A sandwich of the cloth and copper fabric creates the sensor, which decreases in resistance with increasing pressure. The sensors are characterised and production variability within the silicone are tested. Three sensors are incorporated into a glove made to fit around a Southampton Intelligent Hand. The hand adapts its grip shape and force depending on the object held. The technology is adaptable and it can be incorporated in a glove produced to fit any prosthetic hand.
Topics: Hand; Hand Strength; Mechanical Phenomena; Silicones
PubMed: 36068046
DOI: 10.1016/j.medengphy.2022.103845 -
Journal of Global Antimicrobial... Dec 2020The purpose of this study was to evaluate the coating of antimicrobial peptides (AMPs) and polyvinylpyrrolidone (PVP) to the surface of a silicone catheter to reduce...
OBJECTIVES
The purpose of this study was to evaluate the coating of antimicrobial peptides (AMPs) and polyvinylpyrrolidone (PVP) to the surface of a silicone catheter to reduce bacterial growth and to increase hydrophilicity, respectively.
METHODS
Surface characterisation was performed on bare silicone, AMP-coated, PVP-coated and AMP + PVP-coated silicone catheters using attenuated total reflectance-infrared (ATR-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and water contact angle. Antibacterial activity, antibacterial biofilm growth and XTT assay were performed on bare silicone, AMP-coated, PVP-coated and AMP + PVP-coated silicone catheters. Statistical analysis was performed by one-way ANOVA.
RESULTS
The water contact angle of the AMP + PVP-coated silicone catheter was 21.37 ± 2.17° compared with 107.23 ± 0.96°, 74.40 ± 1.76° and 20.77 ± 0.32° for bare silicone, AMP-coated and PVP-coated silicone catheters. Based on in vitro antimicrobial tests, the AMP + PVP-coated silicone catheter had 6.2, 2.2 and 2.5 greater antibacterial activity than that of the bare silicone catheter against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa, respectively. Moreover, bacterial biofilm growth on the surface of the AMP + PVP-coated silicone catheter was minimal as characterised by scanning electron microscopy. MTT assay showed that bare silicone, AMP-coated, AMP + PVP-coated and PVP-coated silicone catheters were non-cytotoxic to 3T3 and human colon cancer (Caco-2) cells.
CONCLUSIONS
This work demonstrates that AMP + PVP-coated silicone catheters have potential clinical application prospects with improved hydrophilicity, excellent biocompatibility, antibacterial activity and a certain antibacterial biofilm effect.
Topics: Biofilms; Caco-2 Cells; Catheters; Humans; Silicones; Staphylococcus aureus
PubMed: 32795517
DOI: 10.1016/j.jgar.2020.07.019 -
Journal of Indian Prosthodontic Society 2021This study aimed to perform an integrative review of the literature on the use of silicone finger prostheses in amputee patients. Searches were performed in the PubMed,... (Review)
Review
This study aimed to perform an integrative review of the literature on the use of silicone finger prostheses in amputee patients. Searches were performed in the PubMed, EMBASE, Web of Science, Scielo, and Cochrane Library databases until July 2021. Descriptors used in this article were: Silicone, finger, rehabilitation, and prosthesis. Clinical research and clinical reports on silicone finger prostheses, available in full and in English were included. Initially, 152 articles were identified. After establishing the inclusion/exclusion criteria, 23 studies were identified and constituted the final sample. Regarding the publication date of the included studies, 17.2% of them were published between 2012 and 2016. Most of the rehabilitations occurred in India (69.9%; n = 16), and the mean age of patients who used prostheses was 38.1 years. The level of scientific evidence of the included studies was IV and VI. Therefore, patients rehabilitated with silicone finger prostheses highlighted significant improvements in functional range of motion, restoration of self-esteem, advantages in psychological therapy, more pleasant social interaction, and changes in their quality of life.
Topics: Adult; Amputees; Artificial Limbs; Fingers; Humans; Quality of Life; Silicones
PubMed: 34810361
DOI: 10.4103/jips.jips_175_21