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Bio-Implants Derived from Biocompatible and Biodegradable Biopolymeric Materials
Published in P. Mereena Luke, K. R. Dhanya, Didier Rouxel, Nandakumar Kalarikkal, Sabu Thomas, Advanced Studies in Experimental and Clinical Medicine, 2021
There are methods to replace a missing tooth by the use of many materials as an implant. Great advancements occurred in the field of science and technology related to the materials for dental implants [74]. There are many types of polymers like ultrahigh molecular weight PU, polyamide, polymethylmethacrylate, polytetrafluoroethylene, and PU used as materials for dental implants. There is a great amount of researches and advancements in the field of biomaterials available for dental implants. Newer materials came up like zirconia, roxolid, and surface-modified titanium implants. These materials have the satisfactory functional requirements and also esthetically pleasing. The earlier material, methyl methacrylate resin implants became failures in many cases [74–76]. In 1969, Hodosh reported that polymers were biologically useful substances [77]. Polymethacrylate based tooth-replica implants was the polymer dental implant developed by Milton Hodosh. When natural tooth replacing polymers are found to be the ideal material for the restoration of function and appearance [78].
Biological behavior of titanium, zirconia or PEEK dental implant-abutments
Published in J. Belinha, R.M. Natal Jorge, J.C. Reis Campos, Mário A.P. Vaz, João Manuel, R.S. Tavares, Biodental Engineering V, 2019
M.B. Sordi, S.N.D. Sarwer-Foner, F.H. Schünemann, K. Apaza-Bedoya, G.M.P. Juanito, B. Henriques, B. Henriques, R.S. Magini, C.A.M. Benfatti
The literature shows that titanium (Ti) is the most widely used material for implant-abutments, then has become the “gold-standard” in oral implantology due to its excellent mechanical properties and biocompatibility (Gómez-Florit et al. 2014). For a long time and even actually, metallic abutments were considered the best option for customized prosthetic solutions. However, the grey color might impair the esthetics. Hence, different materials that are pure white in color should adequately simulate the color of natural teeth (Linkevicius et al. 2015). In the last decades, zirconia (Zr) has emerged in the prosthetic field as a promising esthetic biomaterial with mechanical properties similar or ever higher when compared to titanium. Polyetheretherketone (PEEK) is a polymer that has been extensively studied in biomedicine for implantation of lost tissues, specifically bone. PEEK is not yet used as prosthetic abutments, despite of being applied for dental implants, provisional prostheses, healing abutments or impressing transfers. Therefore, the purpose of this review was to explore the existing literature of biological behaviors of different abutment materials, specifically titanium, zirconia, and polyetheretherketone (PEEK) (Figure 1).
Biomaterials
Published in Manoj Ramachandran, Tom Nunn, Basic Orthopaedic Sciences, 2018
Subhamoy Chatterjee, John Stammers, Gordon Blunn
Alumina (AL2O3) and zirconia (ZrO2) are used in bearing surfaces. Alumina and zirconia share abrasion resistance, low friction and high wettability, resulting in a superior bearing surface. Alumina is particularly brittle and historically had a significant rate of fracture (up to 5%), but processing has reduced the grain size and increased density, reducing fracture risk. Zirconia requires a stabilizer, otherwise it is sensitive to phase changes that can cause micro-cracking and reduce its mechanical properties. Heat and resterilization need to be avoided as they can cause surface roughening. Zirconia had accelerated wear in ceramic-on-ceramic bearings and is only designed for ceramic-on-polyethylene use. The original zirconia was withdrawn but oxidized zirconium has improved fracture resistance and is used in femoral heads and total knee replacements. Due to the high Young’s modulus of ceramics compared to cancellous bone, stress shielding can result in failure, particularly when used for the acetabular component.
Biomechanical evaluation of 3-unit fixed partial dentures on monotype and two-piece zirconia dental implants
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2022
Jefferson David Melo de Matos, Guilherme da Rocha Scalzer Lopes, Leonardo Jiro Nomura Nakano, Nathália de Carvalho Ramos, John Eversong Lucena de Vasconcelos, Marco Antonio Bottino, João Paulo Mendes Tribst
The use of different prosthetic restorative materials does not seem to influence the survival of implant-supported rehabilitation (Sahin et al. 2002), however, the different connections of the implants, the use of different abutments, and the presence of a prosthetic screw can influence the biomechanical behavior restorative treatment (Nishioka et al. 2010; Tribst et al. 2016). In this sense, more information is sought about the use of zirconia abutments and implants (Welander et al. 2008). Thus, the present study showed that the use of different zirconia implant systems can influence the stress distribution and peri-implant bone strain. It was also possible to observe that the use of aesthetic abutments provides satisfactory results in bone strain, corroborating with a previous study (Nevins et al. 2011) that presented promising results for the use of zirconia abutments in the preservation of peri-implant tissues.
Effect of cementation techniques on fracture load of monolithic zirconia crowns
Published in Biomaterial Investigations in Dentistry, 2021
Janne Angen Indergård, Anneli Skjold, Christian Schriwer, Marit Øilo
The development of yttria-stabilized tetragonal zirconia polycrystalline (Y-TZP) for dental purposes has resulted in a range of different products which can be used as a core material as well as a monolithic restoration without the use of veneering porcelain [1,2]. The material group possesses several beneficial qualities such as high fracture toughness and strength, as well as good biocompatibility [3,4]. There are several aspects that can explain the good mechanical properties of zirconia. The industrial production of homogeneous zirconia blocks leads to few flaws and imperfections [5]. The machining of restorations results in restorations with good fit and fewer flaws than hand-made restorations [5]. There are several different types of dental zirconia materials available. The main difference among the materials is the amount of added stabilizing oxide, ranging from 3 mol% (1st generation) up to >5mol% (3rd generation) [2,3]. A yttria content of 3 mol% results in the metastable 3Y-TZP (3Y zirconia). Increasing the amount of yttria to 5 mol% results in a partially stabilized zirconia with a high cubic content (5Y-PSZ, 5Y zirconia). The increase leads to an enhancement in the materials’ optical properties, as cubic phase crystals are transparent [6]. The increased content of the cubic phase has, however, shown to give a significant reduction in the mechanical properties of the materials [3,7,8].
Assessment of stress/strain in dental implants and abutments of alternative materials compared to conventional titanium alloy—3D non-linear finite element analysis
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2020
Pedro Henrique Wentz Tretto, Mateus Bertolini Fernandes dos Santos, Aloisio Oro Spazzin, Gabriel Kalil Rocha Pereira, Atais Bacchi
Among those alternatives, the titanium-zirconia alloy presented success rates and peri-implant bone resorption similar to titanium (Iegami et al. 2017) with the advantage of presenting a slightly lower modulus of elasticity (100 GPa) (Akça et al. 2015). Still, the titanium-niobium alloy with 70% porosity, known as ‘porous titanium’, reached an elastic modulus much closer to that of the bone (∼60 GPa), good biocompatibility, greater bone growth, and demonstrated superior corrosion resistance in comparison to pure titanium (Xu et al. 2013). Another clinical standpoint to be considered is that titanium implants also present the potential for discoloration of peri-implant gingival tissue and possible hypersensitivity (Schwitalla and Müller 2013), thus, metal-free alternatives to titanium were investigated. Ceramics, more specifically tetragonal zirconia stabilized with yttrium, a polycrystalline ceramic, has shown to have a high survival rate and little marginal bone loss, comparable to those found with titanium implants (Deeksha et al. 2012; Pieralli et al. 2017). There are no reports of substantial accumulation of bacteria around this material (Deeksha et al. 2012). As for the mechanical properties, it has sufficient fracture strength to withstand the masticatory loads. In addition to the biological and mechanical points, zirconia becomes an aesthetic alternative to titanium implants (Deeksha et al. 2012).