Open Access

Original Research Articles

Article ID: 22

Classification and research progress of CAD/CAM ceramic materials

by Xinwei GUO, Zhimin ZHANG, Hongyan ZHAO

Ecomaterials, Vol.4, No.1, 2024;

Currently, the most commonly used dental CAD/CAM restorative systems are ceramic materials, which can be divided into resin-ceramic composites, polycrystalline ceramics and glass ceramics according to the differences in composition. Different types of ceramics have major differences in mechanics and aesthetics and need to be selected according to clinical needs and patient demands. Each material has its own advantages and disadvantages, for example, glass ceramics are highly transparent but brittle, polycrystalline ceramics are strong but less transparent, and resin-ceramic composites combine the advantages of glass ceramics and resin materials but are less strong. In this paper, we systematically review the compositional classification, the characteristics of each type of ceramic, and recent research advances to help guide clinical selection of CAD/CAM materials.

Open Access

Articles

Article ID: 20

The concept of "osteoimmunomodulation" and its application in the development of "osteoimmune-smart" bone substitute materials

by Zetao Chen, Xiaoshuang Wang, Linjun Zhang

Ecomaterials, Vol.4, No.1, 2024;

The traditional biological principle for developing bone biomaterials is to directly stimulate the osteogenic differentiation of osteoblastic lineage cells, the direct effector cells for osteogenesis. This strategy has been successful for the development of bone biomaterials. However, recent progress in bone biology has revealed the vital role of the local bone microenvironment, especially the immune environment, in controlling osteogenesis. Interdisciplinary osteoim-munology has found that the osteoimmune and skeletal systems are closely related, sharing numerous cytokines and regulators. In addition, immune cells play an important role in the physiological and pathological processes of the skeletal system, suggesting that neglecting the importance of the immune response is a major shortcoming of the traditional strategy. Based on this principle, we propose a novel “osteoimmunomodulation”-based strategy to meet the strict requirements of new-generation bone biomaterials: instead of directly

Open Access

Articles

Article ID: 19

The effect of the osteoimmunomodulatory mechanism on implant osseointegration and bone biomaterials induced bone regeneration

by Jiang Chen, Xuxi Chen, Lin Zhou

Ecomaterials, Vol.4, No.1, 2024;

With the development of implant dentistry and biomaterials, dental implants have become the first rehabilitative option proposed for the treatment of missing teeth. Most studies about dental implants and biomaterials currently focus on osteogenesis and the osseointegration of the implant, neglecting the importance of the immune response. In recent years, the development of osteoimmunology has been one of the greatest achievements in bone biomaterials; osteoimmunology has revealed the vital role of immune cells in regulating bone dynamics, implying the value of studies on materials with favorable osteoimmunomodulatory properties. This article reviews the integration between bone tissue and implants and summarizes the effects of the immune response during osseointegration and new bone formation to show the importance of regulating the immune response in this process. The effect of macrophages on osteogenesis and osteoclastogenesis is then reviewed due to the high plasticity and multiple roles of macro

Open Access

Articles

Article ID: 23

Biodiesel production from fats extracted from coffee husks: esterification with H2SO4 and transesterification with KOH

by Aiello-Mazzarri Cateryna, Salazar Yenmilet, Urribarrí Aidin, Arenas-Dávila Elsy, Sánchez-Fuentes John, Ysambertt Fredy

Ecomaterials, Vol.4, No.1, 2024;

 The search for non-food feedstocks is one of the main challenges in the production of biofuels. For biodiesel, research is oriented towards the use of non-conventional crops, as well as towards residues or wastes with a high content of fats and oils. Coffee grounds contain a good proportion of fats and are a commercial and domestic waste. In this work, the production of biodiesel using fats extracted from coffee grounds was evaluated in a two-step process. The fats extracted from coffee grounds with boiling to reflujo with hexane as solvent presented high acidity, 32.07 ± 0.01% (70.24 ± 0.03 mg KOH/ g fat), indicating a high content of free fatty acids (FFA). First, the fats were esterified at 60°C and 100 rpm, varying the reaction conditions. At the best conditions, 0.7% H₂SO₄ concentration, 1:6 GMR:MeOH for 120 min, the acidity decreased below 1%, with 94.92% FFA conversion to methyl esters. They were subjected to a transesterification process with KOH (1.5% m/v) in the presence of methanol (RMG:MeOH of 1:15) at 60°C and 100 rpm for 30 min. The biodiesel was separated by decantation and purified by successive washes with acidified water, which resulted in a mixture of methyl esters of linoleic (48.40%), palmitic (36.21%), stearic (8.69%) and oleic (6.69%) acids, whose properties conform to the requirements of ASTM D 6751 and EN 14214.

Open Access

Articles

Article ID: 27

Study on biomimetic phospholipid modification of aliphatic polyester biomaterials

by Xiaomin ZHANG, Jin DENG

Ecomaterials, Vol.3, No.1, 2023;

Abstract: It is low feasibility using plasma energy particles to excite, ionize and break bonds molecules on the surface of aliphatic polyester biomaterials to produce new topological structures. The biomimetic phosphatidylcholine modification technology of aliphatic polyester biomaterials was studied. The phosphatidylcholine monomer [2 (methacryloxy) ethyl]phosphatidylcholine was synthesized by reaction of 2 chloro 1, 3, 2 dioxaphosphoric heterocyclic pentane with different raw material solutions; the phosphatidylcholine[2 (methacryloxy) ethyl]phosphatidylcholine, acrylonitrile and water were copolymerized to form PANCMPC; the phosphatidylcholine [2 (methacryloxy) ethyl]phosphatidylcholine was replaced by PANCMPC, and PANCHEMA was obtained by repeated copolymerization. PANCHEMA was reacted with 2 chloro 2 oxygen 1, 3, 2 dioxophosphorus heterocyclic pentane, and then opened with trimethylamine to form biomimetic phospholipid modified PLCANCP. Experiments show that the proposed technology has good hydrophilicit

Open Access

Articles

Article ID: 18

Effects of graphene/PLGA composite scaffolds on proliferation and differentiation of bone marrow mesenchymal stem cells

by Ao Zheng, Lingyan Cao, yang Liu, Jiannan Wu, Xinquan Jiang

Ecomaterials, Vol.3, No.1, 2023;

Objective: This study aimed at fabricating three-dimensional porous graphene (G)/poly(lactic-co-glycolic acid (PLGA) composite scaffolds and establishing the potential for further application of G/PLGA porous scaffolds in bone tissue engineering. Methods: Different concentrations of graphene was mixed with PLGA (G/PLGA, wt. ‰: 0, 0.5‰, 5‰). Results: Scanning electron microscopy confirmed the inner connected porous structure of the three-dimensional G/PLGA scaffold as well as the uniform distribution of graphene in the scaf-folds. CCK-8 test indicated that G/PLGA porous scaffolds had no obvious cytotoxicity. Compared with BMSCs seeded on PLGA scaffold, the ALP activity of BMSCs seeded on the G/PLGA scaffolds increased and the expression of bone related genes was significantly up-regulated with increase of G concentration. G/PLGA porous scaffold containing 5‰ graphene showed more obvious effects on osteogenic differentiation. Conclusions: The G/PLGA three-dimensional porous scaffold prepared in this research possessed good biocom-patibility and could promote osteogenic differentiation of BMSCs in vitro. Thus, it has been expected to be used as a scaffold for bone tissue engineering.