Tissue Engineered Successful Reconstruction of a Complex Traumatized Lower Extremity

Introduction: Tissue engineered reconstruction is a minimally invasive approach for healing major complex wounds successfully. It combines accurate, conservative debridement with a specially adapted suction method, platelet-rich plasma (PRP) injections, and biomaterial application to salvage injured tissues and grows new soft tissues over wounds. Case Report: A healthy young man in his early 30s presented to our emergency department with complex knee-thigh injuries following a high-velocity automobile accident. Degloved anterolateral thigh, severe thigh muscle injuries, and ruptured extensor patellar mechanism were observed. Accurate conservative (as opposed to radical) debridement and PRP injections salvaged the injured muscles and tendons. Specially carved reticulated foam wrapped around the injured ischemic muscles, followed by low negative, short intermittent, cyclical suction therapy. Wound exploration 4 days apart revealed progressive improvements with considerable vascularization of the injured soft tissues within 2 weeks. Thereafter, meticulous reconstruction of the salvaged muscles and tendons restored anatomical congruity. An absorbable synthetic biomaterial covered the sizeable open wound with vast areas of exposed tendons. Five weeks later, exuberant granulating tissue ingrowth within the biomaterial filled up the tissue defect. A split-skin graft covered the remaining raw areas, which “took” completely. Early rehabilitation enabled the patient to return to active work, play contact sports, and perform strenuous activities effortlessly. Conclusion: Minimally invasive tissue engineered reconstruction is a novel approach using a series of simple minimally invasive procedures. It lessens the duration of surgery and anesthesia, maximizes soft-tissue salvage, lowers morbidity, minimizes hospitalization, saves costs, and improves the patient’s quality of life significantly. Keywords: Mangled extremity, Limb salvage, Financial, Trauma, Modified negative pres

Progress in the application of spider silk protein in medicine

Spider silk protein has attracted much attention on account of its excellent mechanical properties, biodegradability, and biocompatibility. As the main protein component of spider silk, spidroin plays important role in spider spinning under natural circumstances and biomaterial application in medicine as well. Compare to the native spidroin which has a large molecular weight (>300 kDa) with highly repeat glycine and polyalanine regions, the recombinant spidroin was maintained the core amino motifs and much easier to collect. Here, we reviewed the application of recombinant spider silk protein eADF4(C16), major ampullate spidroin (MaSp), minor ampullate spidroin (MiSp), and the derivatives of recombinant spider silk protein in drug delivery system. Moreover, we also reviewed the application of spider silk protein in the field of alternative materials, repairing materials, wound dressing, surgical sutures along with advances in recombinant spider silk protein.

Porous Sponges from the Mesocarp of Theobroma Cacao L. Pod Shells for Potential Biomaterial Applications

Lignocellulosic materials have garnered significant attention in recent years to generate biomaterials, but nothing has been investigated with cacao residues of significant importance in Ecuador. This study's objective was to generate porous, three-dimensional sponges from cacao pod shell mesocarp with potential use in biomaterial application. Discs from the mesocarp of cacao pod shells were subjected to neutral, acid, and alkaline treatments, at 25oC and 100oC, followed by washing and lyophilization. Sponge composition was evaluated, with the alkaline treatment resulting in the highest cellulose content and the lowest percentage of lignin, with the removal of hemicellulose corroborated by FITR. The sponges presented high water absorption capacities, which increased with the treatment temperature; mainly, the alkaline generated structures had the largest capacity. The sponges' porosity also depended on the treatment, with the acid and alkaline treatments generating larger pores, which significantly grew with treatment temperature. Preliminary in vitro cytotoxicity tests were carried out using Wharton's jelly mesenchymal stem cells, according to ISO 10993.5.2009, with none of the materials being cytotoxic; however, those with greater lignin contents resulted in lower cell viability. In general, it is considered that the alkaline generated sponges presented the more significant potential for biomaterial applications, which could be further tested with In vitro cell proliferation and differentiation studies and possible in vivo assays.

DEPOSITION Ti-Sn ON AISI 316L SUBSTRATE WITH SURFACE MECHANICAL ALLOYING TREATMENT (SMAT) FOR BIOMATERIAL APPLICATION IN SIMULATED BODY FLUID

The properties of biomaterials such as biocompatibility, which is non-allergic and non-toxic to be the main requirements that must be owned by the biomaterials because of the presence of direct contact between the biomaterial with body parts. Therefore the study of biomaterials is constantly carried to repair the biocompatibility. In this research, the improvement of the properties the compatibility of the metal alloy AISI 316L with superimposed ideal bio-inert Ti-Sn with the method of Surface Mechanical Alloying Treatment. Manufacture of the alloy with bio-inert Ti-Sn using a variation of the composition of Sn of 10% and Sn 20% done using Mechanosynthesis process. The results of the process are sintered with the variation of temperature of 800oC and 900oC for 2 hours and then were characterized by an optical microscope. Corrosion testing of the alloy was carried out with Polarization Tafel System Three Electrode method for 10 minutes. The results of characterization with an optical microscope shows there is a layer of bio-inert Ti-Sn the results of the process of SMAT of AISI 316L. The results of corrosion testing on alloy AISI 316L Ti-Sn in a solution of SBF showed that the content of Ti-10%Sn with a temperature of 800oC the obtained corrosion rate 4.785 MPY and at 900oC amounted to 4.155 MPY as well as on the content of Ti-20%Sn with a temperature of 800oC the obtained corrosion rate 3.525 MPY and at 900oC amounted to 3.234 MPY. Keywords: Biocompatible; Biomaterial; AISI 316L; Ti-Sn; Corrosion Rate; Allergic Reaction; Deposition.

Karakteristik dan Aplikasi Selulosa Kulit Jagung Pada Pengembangan Hidrogel

Corn is one of the staple food crops widely consumed by Indonesians, thus has potensial in producing an abundant amount of corn husk waste. Cellulose contained in corn husk is about 44%, so the material has the potential to be source of natural fiber cellulose. The development of hydrogels from natural polymers such as cellulose is very promising especially for biomaterial application. Cellulose fiber was obtained through several stages: dewaxing, pulping, delignification, bleaching and cellulose purification. This study aimed to determine the most effective solvent in cellulose extraction of corn husk, the research carried out with different solvent such as, hydrogen peroxide (H2O2), sodium hypochlorite (NaOCl) and hydrocloric acid (HCl). Based on the functional group formed on the analysis of FTIR, shows that the extraction method using H2O2 as solvent can remove hemicellulose and lignin from the cellulose structure and the most white cellulose fiber obtained from the extraction with H2O2 solvent. Cellulose obtained from previous step was used for hydrogel production. The hydrogel showed different absorption capacity depend on temperature and ratio of glutaraldehide to cellulose. The highest water absorption capacity of 250% obtained by hidrogel with ratio 1:2 at 25oC.

Fabrication of Poly(pentaerythritol tetrakis (3-mercaptopropionate)/dipentaerythritol penta-/hexa-acrylate)HIPEs Macroporous Scaffold with Alpha Hydroxyapatite via Photopolymerization for Fibroblast Regeneration

Synthetic biomaterials that can be structured into porous scaffolds for support cell growth have played a role in developing the field of tissue engineering. This research focused on combination of biodegradable emulsion template along with the assisting of low-cost polymerization reaction. The appendage of ester-based surfactant, Hypermer B246, played a vital role which gave an outstanding dispersion in HIPEs system and degradability. PolyHIPEs were prepared by using domestic ultraviolet light source for producing a multiscale porosity material. The morphology showed a promising result of poly(pentaerythritol tetrakis (3-mercaptopropionate)/dipentaerythritol penta-/hexa-acrylate)HIPEs with varied Hypermer B246 surfactant concentration resulting in the pores size increased in between 51.2 ± 9.8 µm to 131.4 ± 26.32 µm. Cellular moieties of poly(TT/DPEHA) HIPEs were confirmed by using SEM while inclusion of hydroxyapatite were confirmed by SEM, FTIR and EDX-SEM and quantified by thermogravimetric analysis. The maximum stress and compressive modulus of the obtained materials were significantly enhanced with HA up to five percent by weight. Poly(TT/DPEHA)HIPEs with HA showed the ability for the cell attachment and the adhesion/proliferation of the cells, suggested that poly(TT/DPEHA) HIPEs with HA were suitable for biomaterial application.

Tooth Discoloration after Regenerative Endodontic Procedures with Calcium Silicate-Based Cements—An Ex Vivo Study

The aim of the present ex vivo study was to assess and compare coronal discoloration induced by four endodontic biomaterials used in regenerative endodontic procedures (REPs). Root resection was executed horizontally, 2 mm apical to the cementoenamel junction, in all fifty-four teeth. After accessing the pulp chamber, specimens were randomly divided in groups and filled with either saline solution or blood, followed by calcium silicate-based cements (CSCs) placement: ProRoot mineral trioxide aggregate (MTA) (Dentsply Sirona), Biodentine (Septodont), TotalFill BC (FKG), or pulp capping material (PCM) (Coltène). Color change (ΔE) was assessed using the L* a* b* system at five different timepoints (before and immediately after biomaterial application, 72 h, 7 days, and 6 months). The significance level for statistical analysis was set at p < 0.05. There are statistically significant differences regarding ΔE over time (p < 0.001). Statistical differences are found considering material (p < 0.001), treatment (p = 0.007), or both (p = 0.002). If solely the material or treatment is considered, regardless of time, statistically significant differences are detected (p < 0.001). After a six-month period of evaluation, blood exposure might be a critical factor in biomaterials’ color variation. Biodentine presents the lowest discoloration potential, followed by TotalFill and PCM, albeit without statistically significant differences. MTA exhibited the greatest color variation. The selection of biomaterial should consider the material’s discoloration potential.