UP-AND-COMING NANOSTRUCTURED HYBRID-MATERIALS FOR REGROWING TOOTH TISSUES
Tissue engineering regarding dental tissues is a very dynamic field of research owing to the advancement in technology and the need for better and improved treatments in dentistry. Billions of people have suffered from losing teeth and dental diseases so that generating natural dental tissues is more appreciate than artificial tooth implantation. Tissue Engineering is attributed to stem cells and scaffolds, and this known triad is graduated to serve specific purposes in dentistry sector. Giving general ideas of how nanostructured hybrid materials have to offer to the current dental problems, this paper reviews the literature on Nano-morphological features of stem cells, dental tissues found within the oral area, the signaling molecules utilized in the tissue engineering, and the hybrid scaffolds that guide reconstruction of periodontal tissues. Finally, the future and actual responsibilities of nanotechnologies pertaining tissue engineering as applied dentistry (Mitziadis, Woloszyk, & Jimenez-Rojo, 2012).
Keywords: Stem cells; scaffolds; nano-materials; hybrid materials, tissue engineering; dentistry; signaling molecules.
Stem cell biology represents an attractive therapeutic intervention in regenerative dentistry that compliments other restorative techniques. There is a need to design Nanostructured hybrid materials for controlling cell differentiation and fate such as scaffolds and biomimetic matrices. Integrating stem cell biology and nanotechnology allow the creation of complex materials with detailed structures in high density or porous form. Apart from that, nanoparticles also aid in the image and the diagnosis of the targeted treatment which can upgrade from traditional surgery interventions in regenerative dentistry to a higher level of precision. Notably, hybrid nanoparticles and scaffolds are administered to patients that will escalate the regenerative process of dental pathological tissues when active biological components already made of stem cells (Besinis, A, De Peralta, T, Tredwin, C.J, & Handy, 2015).
The enamel and dentin are the hardest tissues in the body. Both form as a result of reciprocal and sequential interactions between oral epithelium cells and cranial neural mesenchyme. Mesenchymal forms the dental pulp and dental follicle. The epithelium is responsible for the formation of ameloblast while a fraction of the dental pulp cells disintegrates into odontoblasts which produce the dental matrix. Finally, the ameloblast forms the enamel completing the mineralization of the tooth crown. However, the mineralized dental tissues are vulnerable to harmful agents such as bacteria and traumatic injuries that disrupt tooth integrity (Besinis, A, De Peralta, T, Tredwin, C.J, & Handy, 2015).
Damaged dentin can be mended naturally through reactionary dentinogenesis. And most clinics use cell-occlusive inhibitors such as cellulose which restrict repopulation of the periodontium favoring the growth of periodontal ligament (PDL) cells enhancing regeneration of the periodontium. Unfortunately, the natural regenerative ability of the dental tissues is minimal to restore a damaged tooth so that the function of stem cell biology integrated with tissue engineering technology enhances cell-based dental tissue regeneration (Mitziadis, Woloszyk, & Jimenez-Rojo, 2012).
Hybrid Nanomaterials for tissue engineering in dentistry.
Hybrid materials consist of inorganic and organic phases that appear in bio-composites, ceramic, and polymers. The component of ceramic particles, for example, fine Silica or ?-LiAlSiO_4 and polymers, can be used in replacing real dental materials (Guido Kickelbick, 2007). This component can grow crystal lattices where cations and anions in the lattices are free to exchange with external ions resulting in extraneous ions will change the lattices. Hydroxyapatite HAP Ca5(PO4)3OH are more readily to accept different ions molding hydroxyl, and fluoride usually replaces phosphate ions in tooth tissues (Need cite).
Ultimately, why hybrid nanomaterials are so important? Because they provide unique quality requirements for biomedical implantation such as non-corrosion, hardness, elasticity, and anti-bacteria. The mechanism of growing hybrid materials in dentistry and bones is similar in the way of building block …..(more)……Also, composite materials are needed in dentistry implantation because they are very flexible and high-density. Nanoscale structures of tissues have been developed to control the absorption of wanted proteins and eliminate unwanted ones with the help of ceramics and polymers will prevent toxically, corrosion and bacterial contamination. (Need cite)
More about chemical reaction and growing mechanism of hybrid materials and how this mechanism plays a role in regrowing tooth tissues (be careful teeth cant regrow like bones but is it any hope for hybrid materials take the job)…
Clinical activities are changing rapidly due to the applications of nanomaterials and tissue engineering which have revolutionized processes in dentistry. Nanomaterials in dentistry were first applied in 2002 with an integration of Nano-fillers for dental reconstruction from composite resins. Since the first application was successful, nanomaterials have been used widely to improve the materials used in restorative dentistry. Such efforts are seen during the inhibition of primary oral and dental biofilm-dependent diseases. Similarly, nanomaterials are employed in the diagnosis of pre-malignant and malignant diseases and during the formation Nano-textured surface in implantology (Bhavikatti, S.K, Bhardwaj, S, & Prabhuji, 2014).
The introduction of new membranes that can maximize controlled regeneration of tissues in periodontology with layers to restore the lost bones in an oral surgery paved the way for tissue engineering in dentistry based upon three principle phases of tissue engineering: scaffolds, signaling molecules, and stem cells. Recently the knowledge of nanomaterials and tissue engineering has been integrated into dentistry coupled with the introduction of nanotechnologies in the design of scaffolds both rigid and soft. More so, growth factors and stem cells, together with submission of the biomodulation strategies have been used to improve dental tissue reconstruction (Mitziadis, Woloszyk, & Jimenez-Rojo, 2012).
How nanostructure hybrid-materials regrow the lost bones due to oral surgery….implantation the bone (jaw bone is the same like other bones so it is easy to do this job but teeth are not the same as bones, it cant regrow the damage parts in the current situation but if we synthesized nanoparticles ….)
Process of building blocks, dentrimer, layer…
1) The Dental Structure and Diseases of Periodontal Tissues.
The teeth are comprised of the enamel, the dentin, and the centum which are adamant dental tissues. The three hard tissues are composed of chemical compositions with varying percentages because both dentine and cement have an organic component, while the enamel is purely inorganic.
The inorganic component of enamel is organized in rods (or prisms) made of hexagonal apatite crystals. Mineral content and density of these crystals are uneven and decrease from the surface of enamel to the dentine-enamel border. Dentin is composed of an inorganic portion 70% of hydroxyapatite that is imperfectly crystallized, an organic portion up to 20% of type II collagen fibers and 10% of water (Young, C. S, Abukawa, H, Asrican, R, & Ravens, M., 2005).
How hybrid materials form crystallized and bio-mechanism of mineral growing…
Discuss about covalent bond in dental structure and hybrid materials, bond between real teeth with hybrid materials…
Material tissue bonding…
The most common pathological conditions that damage the teeth include cervical erosions, periodontal disease, periodontal trauma, and total loss of teeth. Such situations are not resolvable in clinics without tissue engineering methods.
2) Stem Cells located in Periodontics and Tooth Tissues in Dentistry
Stem cells are used to reconstruct dental tissues that are partly or wholly damaged. These cells are of non-dental origin and can be classified together with those from adipose tissues and bone marrow. Such cells are used as alternatives when teeth are completely damaged. Cells with periodontal and dental origin are preferred because of their affinity and compatibility with the target tissues. These cells can be classified into three categories (Besinis, A, De Peralta, T, Tredwin, C.J, & Handy, 2015).
a. Pluripotent cells – They are dental pulp pluripotent stem cells (DPPSC) used in the regeneration and reconstruction of tissues in the enamel.
b. Mesenchymal cells – They are dental pulp stem cells originating from exfoliated deciduous teeth.
c. Epithelial cells – They are eliminated in the third molars pulp and arise from epithelial rests.
Discuss more about the role of stem cells
3) The Primary Factors that feature the growth and Signaling Molecules
Biological mediators are used to stimulating or inducing the growth of cells present throughout tissue engineering as applied in dentistry. In the case of pulp-dentin complex, stimulative growth may arise from the reconstruction of degraded dentin matrix or regeneration process.
Discuss more about the role of signaling molecules
4) The primary Biomaterials contribute to structure Hybrid Scaffolds/Matrices
Ideally, a scaffold (hydrogels) serves as an appropriate model for the reconstruction of tissues in dentistry [more about scaffolds and hydrogels in here]. A suitable building tissue exhibits features such as ease of handling, pore shape, sufficient porosity, and a significant level of permeability. More so, the tissues should facilitate elimination of the byproducts from cells and allow vascularization. Tissue engineering in dentistry requires a ductile scaffold to reproduce the matrix and size of the target tissues (Bhavikatti, S.K, Bhardwaj, S, & Prabhuji, 2014).
Due to the complexity of the target tissues owing to their small size, it’s hard to access the receiving region. Hence, scaffolds are made soft and injectable. Biometric materials used to make the scaffolds can, therefore, be categorized based on their sources either synthetic or natural. Similarly, regarding rigidity, the scaffolds can be classified as soft or hard. Rigid hydrogels are built from biomaterials used to direct the reconstruction of cartilage. Making such materials very suitable for surgery (Young, C. S, Abukawa, H, Asrican, R, & Ravens, M., 2005).
Significant changes are experienced in the tissue engineering in dentistry ranging from clinical treatments to surgery while botherations of tissue engineering could be a slow process and require high sterilized environment both in growing and planting the tissue (rewrite). Various studies on hybrid nanomaterials focused in analyzing soft and hard hydrogels (scaffolds) are conducted in animals with only a few based on human patients. This paper depicts a real life context of literature about hybrid nanomaterials. Starting from the morphological explanation of tooth tissues and focuses on the dental diseases that are solvable using tissue engineering methods (Bhavikatti, S.K, Bhardwaj, S, & Prabhuji, 2014).
The development of nanotechnology presents exciting features to enhance tissue regeneration in dentistry. There is no doubt that combinatorial application of hybrid nanostructures, the signaling drugs, and hybrid stem cells have been verified to enhance tissue regeneration in the damaged regions in animals. However, it is speculated whether there will be a considerable impact when the same methods are applied to Humans (Young, C. S, Abukawa, H, Asrican, R, & Ravens, M., 2005). The combination of various properties of inorganic and organic components in the unique material is achievable so that hybrid nanomaterials give hope for future restoration real human tooth tissues… (rewrite this).
Besinis, A, De Peralta, T, Tredwin, C.J, & Handy. (2015). Review of Nanomaterials in Dentistry. Oral Microenvironment, Clinical Applications, Hazards, and Benefits.
Bhavikatti, S.K, Bhardwaj, S, & Prabhuji. (2014). Current applications of nanotechnology in dentistry: A review. General Dent.
Mitziadis, T., Woloszyk, A., & Jimenez-Rojo, L. (2012). Combining nanostructured materials and stem cells for dental tissue regeneration. Nanomedicine.
Young, C. S, Abukawa, H, Asrican, R, & Ravens, M. (2005). Tissue-engineered hybrid tooth and bone. Tissue engineering.
Guido Kickelbick (2007). Hybrid Materials. Wiley-VCH.