"3A+2P"医患互动对糖尿病患者种植义齿修复后 的糖代谢及牙周指数的影响

目的 探究“3A+2P”医患互动对糖尿病患者种植义齿修复后的糖代谢及牙周指数的影响。方法 选取2018年1月至2019年1月收治的糖尿病种植义齿修复后患者100例，按随机数字表法分为2组，各50例。对照组给予常规干预，观察组给予“3A+2P”医患互动干预，对比2组糖代谢指标、牙周指数及种植义齿存留率。结果 观察组干预3个月后糖代谢指标优于对照组，差异有统计学意义（P<0.05）；观察组干预3个月后牙周指数低于对照组，差异有统计学意义（P<0.05）；观察组干预3个月后种植义齿留存率高于对照组，差异有统计学意义（P<0.05）。结论 “3A+2P”医患互动应用于糖尿病患者种植义齿修复中，可有效改善患者的糖代谢指标，降低其牙周指数，同时还可提高种植义齿留存率，值得推广。     

Toward optimizing dental implant performance: Surface characterization of Ti and TiZr implant materials

Objective

Targeting understanding enhanced osseointegration kinetics, the goal of this study was to characterize the surface morphology and composition of Ti and TiZr dental implant substrates subjected to one of two surface treatments developed by Straumann. These two treatments are typically known as SLA and SLActive, with the latter resulting in more rapid osseointegration.

Titanium hydride and hydrogen concentration in acid‐etched commercially pure titanium and titanium alloy implants: a comparative analysis of five implant systems

Objectives: Acid etching is a popular method to texture the surface of dental implants. During etching, the titanium oxide protective layer is dissolved and small native hydrogen ions diffuse into the unprotected implant surface. They enrich the implant surface with hydrogen and precipitate into titanium hydride (TiH). The aim of this study was to measure the concentration of TiH at the implant surface and the total concentration of Hydrogen at five commercially available implant systems, made of either commercially pure (cp) titanium or titanium alloy. Material and methods: X‐Ray diffraction (XRD) was conducted on each implant system to determine the compounds present at the implant surface. Following a TiH₂/Ti calibration curve, the concentration of TiH was determined. Concentration of hydrogen in the implants was measured by the inert gas fusion thermal conductivity/infrared detection method. Results: XRD data showed that TiH was present on all cp titanium implants but not on the alloyed implants. TiH concentration varied between 5% and 37%. Hydrogen concentration varied between 43 and 108 ppm, no difference in uptake was found between the cp titanium and alloyed implants. Low solubility of hydrogen in α‐titanium is responsible for precipitation into TiH. Stronger etching conditions led to higher concentration of TiH2‐x. Conclusion: High solubility of hydrogen in the β‐phase of the alloy is preventing hydrogen from precipitating into TiH. All implants, even those lacking TiH at the surface, were enriched with hydrogen. In all implants, hydrogen concentration was within the normative limit of 130 ppm. To cite this article:
Szmukler‐Moncler S, Bischof M, Nedir R, Ermrich M. Titanium hydride and hydrogen concentration in acid‐etched commercially pure titanium and titanium alloy implants: a comparative analysis of five implant systems.
Clin. Oral Impl. Res. 21 , 2010; 944–950.
doi: 10.1111/j.1600‐0501.2009.01938.x     

Formation of TiO2 nano-network on titanium surface increases the human cell growth

ObjectivesThis study was to improve human cell growth on titanium (Ti) used for dental implants through formation of a nano-network surface oxide layer created by an electrochemical anodization treatment.MethodsAn electrochemical anodization treatment was used to produce a network oxide layer on Ti surface. Surface characterization of the network layer was carried out using thin film X-ray diffractometer and field emission scanning electron microscopy. Human bone marrow mesenchymal stem cells (hMSCs) were made to express green fluorescent protein (GFP) by retroviral transduction. The GFP signal was measured in situ to assess in vitro and in vivo cell growth on Ti surfaces. In vivo experiments on Ti-supported cell growth were carried out on the back skin of nude mice. Alizarin red staining and immunofluorescent staining were used to observe cell differentiation.ResultsA multilayer TiO₂ nano-network was produced rapidly on Ti surface using a simple electrochemical anodization treatment. The TiO₂ nano-network layer on the anodized Ti surfaces significantly improved in vitro and in vivo hMSC growth, as assessed by measurement of GFP fluorescence, relative to hMSC growth on untreated Ti surface. The TiO₂ nano-network layer on the anodized Ti surfaces can also induce the differentiation of hMSCs after 28-day in vivo test.SignificanceThe formation of TiO₂ nano-network on the Ti surfaces can increase the hMSC growth in vitro and in vivo.     

Atomic layout of an orthodontic titanium mini-implant in human tissue: Insights into the possible mechanisms during osseointegration

Objectives:To evaluate nanoscale molecular interactions in the interface between human bone and orthodontic titanium implants.Materials and Methods:An orthodontic implant (sandblasted with large grit and with an acid-etched surface treated with Ti6A14V alloy) retrieved from the mandible of human after 2 months of healing was used to analyze the molecular interactive mechanism between the implant and the surrounding bone tissue. To preserve the natural state of the sample as much as possible, cryofixation and scanning electron microscope/focused ion beam milling without any chemical treatment were used during sample preparation. Atom probe tomography was used to investigate the chemical composition and structure at the interface between the implant and human bone tissue.Results:Three-dimensional (3D) reconstruction of the whole sample revealed a 20 × 50-nm² plate-like bony element diffusion layer in the sample. The iso concentration analysis of the diffusion layer indicated that the bony element, calcium, and the implant element, titanium oxide, were interspersed with each other. Detailed ionic distribution was illustrated by 3D reconstruction with partial region of interest and one-dimensional concentration profiles of the implant-bone interface.Conclusions:The study results advance nanoscale understanding of osseointegration and suggest a potential nanostructure for increasing bond strength of biomaterials to bone.     

Techniques for dental implant nanosurface modifications

PURPOSE

Dental implant has gained clinical success over last decade with the major drawback related to osseointegration as properties of metal (Titanium) are different from human bone. Currently implant procedures include endosseous type of dental implants with nanoscale surface characteristics. The objective of this review article is to summarize the role of nanotopography on titanium dental implant surfaces in order to improve osseointegration and various techniques that can generate nanoscale topographic features to titanium implants.

MATERIALS AND METHODS

A systematic electronic search of English language peer reviewed dental literature was performed for articles published between December 1987 to January 2012. Search was conducted in Medline, PubMed and Google scholar supplemented by hand searching of selected journals. 101 articles were assigned to full text analysis. Articles were selected according to inclusion and exclusion criterion. All articles were screened according to inclusion standard. 39 articles were included in the analysis.

RESULTS

Out of 39 studies, seven studies demonstrated that bone implant contact increases with increase in surface roughness. Five studies showed comparative evaluation of techniques producing microtopography and nanotopography. Eight studies concluded that osteoblasts preferably adhere to nano structure as compared to smooth surface. Six studies illustrated that nanotopography modify implant surface and their properties. Thirteen studies described techniques to produce nano roughness.

CONCLUSION

Modification of dental osseous implants at nanoscale level produced by various techniques can alter biological responses that may improve osseointegration and dental implant procedures.     

Peri-implant tissue response to TiO2 surface modified implants

Objectives: The objective of this study was to evaluate peri‐implant soft tissue attachment and alveolar bone height on nanoporous TiO₂ thin film on commercial titanium dental implants compared with unmodified standard implants. Material and methods: In six adult beagle dogs, the mandibular premolars P2–P4 were extracted bilaterally. Sol–gel‐derived nanoporous TiO₂ thin film was produced on smooth coronal part of standard ITI^® Straumann implants (4.1 mm × 8.0 mm) by dip coating method. After 3 months healing period of the extraction sockets modified (n=24) and unmodified (n=11) control implants were placed bilaterally. The animals were killed after 8 weeks and the samples were retrieved and processed for histologic/histomorfometric and TEM/SEM evaluations. Results: Histological examination showed mild or absent inflammatory reaction in peri‐implant connective tissues around the surface modified implants. Further, junctional epithelium (JE)/connective tissue (CT) appeared to be in immediate contact with the experimental implants. Of the experimental implants, 22% were judged to be detached from the implant surface while 45% of the untreated control implants were detached. Dense plaques of hemidesmosomes were found in TEM evaluation of the JE cell membrane facing the surface‐treated implants. In the histomorfometric analysis, the distance between the implant margin and alveolar bone crest was significantly shorter in surface‐treated implants than in the control implants (P<0.02). Conclusion: Nanoporous sol–gel‐derived TiO₂ thin film on ITI^® Straumann dental implants improved soft tissue attachment in vivo.     

Antimicrobial profile of a dental implant abutment coating to prevent adhesion and migration of bacteria and screw loosening

ObjectiveFailure of dental implants treatment is frequently the result of bacterial colonization of implants followed by diseases like peri-implantitis. Recent studies have been made regarding the surface treatment of implants components, namely abutments that are in the interface of the living tissue with the implant. This work aimed at evaluating the antimicrobial profile of a silane-based coating with TiO₂ adapted to an abutment screw, that was also developed as an anti-loosening agent, to prevent adhesion and migration of Gram + and Gram-bacteria, Staphylococcus aureus, and Escherichia coli, respectively.MethodsDirect contact antimicrobial studies were conducted on coated and uncoated samples by resazurin fluorescent assay and cytotoxicity assessment was done via MTT indirect method on days 1 and 4. Sterilizations studies by FTIR analysis were also performed to understand the ideal balance between sterilization efficacy and coating functionality subjecting the samples to ethylene oxide, gamma irradiation, and autoclave sterilization, before antimicrobial testing. The implant system as a whole was also studied for its ability to block bacterial migration and preventing microleakage as well as an assessment of initial bacterial adhesion evaluated by scanning electron microscopy.ResultsDirect contact studies performed on coated samples showed a very high antimicrobial activity, while cytotoxicity assays revealed the coating to be safe and non-leachable. Sterilizations studies showed that the antimicrobial features of the coating were preserved and interchangeable regardless of the sterilization method. The implant system migration studies demonstrated that the implant system works as an efficient barrier for the studied bacteria.SignificanceThe acquired results clearly show that it is possible to obtain a highly functional coating with obvious and marked antimicrobial features that together with an abutment that prevents bacterial migration and versatility in sterilization methodology has a very high potential in the dental implant field.     

Wear particle release at the interface of dental implant components: Effects of different material combinations. An in vitro study

ObjectivesParticle generation from implant components caused by frictional wear affect the surrounding peri-implant tissues. The objective of this study was to evaluate the effect of combining implant and abutment materials on wear and particle release in a dynamical loading setup.MethodsA customized dynamical loading machine was used to subject two implant materials (Titanium and Titanium- Zirconium alloy) paired with two different abutment materials (Titanium and Zirconia) to a cyclic loading set of 240.000 cycles (simulating 1 year of clinical use). The implant and abutment complex was immersed in corrosive liquid to collect particle debris and measure the release of corroded ions. Scanning electron microscopy was used to analyze signs of wear on the components after testing and evaluate the size and composition of particle debris.ResultsWear signs were evident in all material couplings. Particle debris was found on top, inside the implants, and on the abutment heads. The particle size ranged between 0.6 and 16.9 µm, with larger particles composed of Ti. Smaller-sized particles were found in the container liquid ranging from 0.253 to 1.7 µm compared to inside the implants ranging from 3.25 to 95.3 µm. Larger particles were found inside Tizr implants compared to Ti implants. Low levels of ions released due to corrosion were found when measuring content in surrounding liquid.SignificanceParticle generation is evident when subjecting dental implant and abutment couplings in a dynamic loading setup. Internally connected implants hinder the release of larger particles to surrounding container liquid.     

Multifaceted roles of environmental factors toward dental implant performance: Observations from clinical retrievals and in vitro testing

Objective

Oral bacteria and periodontal pathogen have been predominantly linked with early- and late- stage failures of titanium (Ti) dental implants (DI) respectively. This study is based on the hypothesis that bacterial colonization can damage the surface oxide (TiO₂) layer. Early-failed DI were compared with DI post-in vitro immersion in early colonizing oral bacteria; late failed DI were weighed against DI immersed in late colonizing anaerobic pathogens.

Micro-Raman spectroscopic analysis of TiO2 phases on the root surfaces of commercial dental implants

ObjectivesTo identify the TiO₂ phases of the root surface of commercially available titanium dental implants, subjected to various surface treatments.MethodsThe titanium implants studied were: Allfit (ALF), Ice (ICE), IMZ TPS (TPS), Laser Lok (LLK), Prima Connex (PRC), Ospol (OSP), Osseospeed TX (OSS), Osseotite Full (OTF), Replace Select (RPS), SLA (SLA) and Trilobe (TRB). The root parts of the implants (n:2) were analyzed by Raman microspectroscopy employing argon ion laser excitation (514.5 nm wavelength) and a 100 μm × 100 μm sampling area at two randomly selected sites.ResultsThe spectra of OSP and RPS showed the characteristic peaks of anatase, with traces of rutile (RPS). Complex phases composed of anatase, rutile and amorphous TiO₂ were identified in ALF, ICE and LLK. Rutile and amorphous TiO₂ were found in PRC, OSS, OTF, TPS and TRB, whereas rutile and possibly brookite were traced in SLA. In all implants, except OSP and RPS, peaks assigned to organic impurities (CH₂, CH₃) and carbonates were recorded. Ti₂O₃ was identified in OTF, PRC and Al₂O₃ in TRB.SignificanceGreat variations in the TiO₂ polymorphs were registered among the implant root surfaces tested. Considering the important differences in the biological activity of these polymorphs, it can be concluded that provision of information regarding the TiO₂ state on implant surfaces should be a mandatory task for implant manufacturers.     

Histomorphometric assessment of implant coated with mixture of nano-alumina and fluorapatite in rabbits

BackgroundThe application of nanoscale surface modification was found to be useful in the improvement of osseointegration of endosseous dental implants. The fluorapatite (FA)/alumina (Al₂O₃) mixture is recognized for its outstanding bioinertia and can significantly increase the biocompatibility and bioactivity of biomaterials.ObjectiveThe aim of the present work was to evaluate the bone response to nano-alumina- and fluorapatite-coated dental implants using rabbit tibiae.Material and MethodsThe coating was performed using the dip-coating method. Commercially pure titanium screw-type implants were used as a control group. The coated implants were the experimental group. Each group consisted of 12 screws that were surgically implanted in 6 healthy New Zealand rabbits. Histological and histomorphometric evaluations were performed at the bone to implant contact (BIC) interface, bone fraction area occupancy (BAFO) and fibrous tissue at 2 and 6 weeks of healing.ResultsThis analysis showed that the coated implants had more rapid osseointegration than the control group, with a significant difference after 2 and 6 weeks of healing for both groups. The histomorphometric evaluation demonstrated higher values for BIC% and BAFO% and lower values of fibrous tissue in the mixture-coated Ti implants than in the control group.ConclusionThe current study suggested that the nano-alumina and fluorapatite mixture coating is a favourable candidate for rapid osseointegration over uncoated implants.     

Elucidating the corrosion-related degradation mechanisms of a Ti-6Al-4V dental implant

ObjectiveThe Ti-6Al-4V (TAV) alloy is commercially used as a dental implant material. This work seeks to elucidates the origins of degradation of Ti-6Al-4V (TAV) implant alloys that result in peri-implant bone loss. Methods: In this work, a combination of microstructure, surface, and solution analyses was utilized to study the corrosion mechanism of the TAV alloy in oral environments. The corrosion of TAV alloys in the F^--enriched environment of a crevice was evaluated through nanoscale surface analysis. And, the findings were further rationalized via electrochemical means. ResultsOur results suggest the bone loss was caused by crevice corrosion and the consequential release of by-products, and the crevice corrosion was potentially induced by the buildup of corrosive species such as fluorides, which are common additives in dental products. In turn, the corrosion properties of the TAV alloy were evaluated in fluoride enriched environments. Nanoscale analysis of corroded surfaces, carried out using vertical scanning interferometry (VSI) showed that the corrosion susceptibility of the constituent phases dictates the corrosion product species. In specific, the aluminum-rich α phase preferentially dissolves under potential-free conditions and promotes the formation of insoluble Al-Ti oxides. Notably, under conditions of applied potential, oxidative dissolution of the vanadium-rich β phase is favored, and the vanadium release is promoted. SignificanceThese findings elucidate the origins of degradation of TAV-implants that result in the release of corrosion by-products into the local biological environment. More important, they offer guidelines for materials design and improvement to prevent this nature of degradation of dental implants.     

Impurities in commercial titanium dental implants – A mass and optical emission spectrometry elemental analysis

ObjectiveTitanium (Ti) is considered bioinert and is still regarded as the “gold standard” material for dental implants. However, even ‘commercial pure’ Ti will contain minor fractions of elemental impurities. Evidence demonstrating the release of Ti ions and particles from ‘passive’ implant surfaces is increasing and has been attributed to biocorrosion processes which may provoke immunological reactions. However, Ti observed in peri-implant tissues has been shown to be co-located with elements considered impurities in biomedical alloys. Accordingly, this study aimed to quantify the composition of impurities in commercial Ti dental implants.MethodsFifteen commercial titanium dental implant systems were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS) and optical emission spectrometry (ICP-OES).ResultsThe elemental composition of implants manufactured from commercially pure grades of Ti, Ti-6Al-4V, and the TiZr alloy (Roxolid) conformed to the respective ISO/ASTM standards or manufacturers´ data (TiZr/Roxolid). However, all implants investigated included exogenous metal contaminants including Ni, Cr, Sb, and Nb to a variable extent. Other contaminants detected in a fraction of implants included As and the radionuclides U-238 and Th-232.SignificanceAlthough all Ti implant studies conformed with their standard compositions, potentially allergenic, noxious metals and even radionuclides were detected. Since there are differences in the degree of contamination between the implant systems, a certain impurity fraction seems technically avoidable. The clinical relevance of these findings must be further investigated, and an adaptation of industry standards should be discussed.     

Innovative surfaces and alloys for dental implants: What about biointerface-safety concerns?

ObjectivesThe present review article aimed to discuss the recent technologies employed for the development of dental implants, mainly regarding innovative surface treatments and alternative alloys, emphasizing the bio-tribocorrosion processes.MethodsAn electronic search applying specific MeSH terms was carried out in PubMed and Google Scholar databases to collect data until August 2021, considering basic, pre-clinical, clinical and review studies. The relevant articles (n = 111), focused on innovative surface treatments for dental implants and their potential undesirable biological effects, were selected and explored.ResultsNovel texturization methodologies for dental implants clearly provided superficial and structural atomic alterations in micro- and nanoscale, promoting different mechanical-chemical interactions when applied in the clinical set. Some particulate metals released from implant surfaces, their degradation products and/or contaminants exhibited local and systemic reactions after implant installation and osseointegration, contributing to unexpected treatment drawbacks and adverse effects. Therefore, there is an urgent need for development of pre-clinical and clinical platforms for screening dental implant devices, to predict the biointerface reactions as early as possible during the development phases.SignificanceModern surface treatments and innovative alloys developed for dental implants are not completely understood regarding their integrity during long-term clinical function, especially when considering the bio-tribocorrosion process. From this review, it is possible to assume that degradation and contamination of dental surfaces might be associated within peri-implant inflammation and cumulative long-lasting systemic toxicity. The in-depth comprehension of the biointerface modifications on these novel surface treatments might preclude unnecessary expenses and postoperative complications involving osseointegration failures.     

Particle release from dental implants immediately after placement – An ex vivo comparison of different implant systems

ObjectivesMetallic element release during implant placement can lead to mucositis and peri-implantitis. Here, using ex vivo porcine mandibles, the release of metallic elements into the surrounding bone with different material and geometrical designs was quantified.MethodsImplants from BioHorizons® and Straumann® (Bone level, tapered/cylindrical, 3/4 mm body diameter, Ti-CP4/Ti-6Al-4V/Ti-15Zr) systems were used. Micro computed tomography and inductively coupled plasma optical emission spectroscopy was used to visualise and quantify metallic elements in bone, following acid digestion. Implant surfaces were examined with scanning electron microscopy and internalization of implant particles by human gingival fibroblasts (HGFs) and RAW 264.7 macrophages were demonstrated in vitro.ResultsImplants with wider body diameters resulted in higher metallic element release. Ti-6Al-4V implants released significantly more metallic elements in comparison to both Ti-CP4 and Ti-15Zr devices with similar design and dimensions. Tapered Ti-CP4 implants released less compared to those with cylindrical design. Al three types of particles were internalized by HGFs and RAW 264.7.SignificanceTi-CP4 and Ti-15Zr appear to be more suitable materials, however, further studies are required to elucidate the biological effects of the fine particles and/or metallic species from dental implants. Authors would like to raise the awareness in the dental profession community that careful evaluation of the materials used in dental implants and the potential risks of the individual constituents of any alloy are needed. The potential cytotoxicity of Ti-6Al-4V implant particles should be highlighted. Further investigations on the biological effect of the fine particles or metallic species released from dental implants are also needed.     

紫外线光功能化对二氧化钛纳米管表面改性钛种植体骨结合的影响

目的 研究紫外线光功能化对二氧化纳米管钛表面改性钛种植体骨结合的影响。方法 采用预阳极氧化法制备二氧化钛（TiO₂）纳米管表面改性钛种植体，并用波长为250 nm、功率为2mW/cm²紫外线（UVA）对种植体进行处理。将种植体植入SD大鼠股骨，12周后取含种植体骨组织制作组织切片，通过显微镜观察种植体周围骨组织形成情况并计算骨结合率。结果UVA处理组种植体周围新生骨组织多于未UVA处理组，且更致密。UVA处理组和未UVA处理组的骨结合率分别为（72.21±10.42）%和（44.98±9.62）%，两组之间的差异具有统计学意义（P<.05）。结论UVA光功能化TiO₂纳米管表面改性有助于促进钛种植体骨结合。     

High speed imaging of biofilm removal from a dental implant model using ultrasonic cavitation

ObjectivesCurrent instruments cannot clean in between dental implant threads and effectively remove biofilm from the rough implant surface without damaging it. Cavitation bubbles have the potential to disrupt biofilms. The aim of this study was to see how biofilms can be disrupted using non-contact cavitation from an ultrasonic scaler, imaged inside a restricted implant pocket model using high speed imaging.MethodsStreptococcus sanguinis biofilm was grown for 7 days on dental implants. The implants were placed inside a custom made restricted pocket model and immersed inside a water tank. An ultrasonic scaler tip was placed 0.5 mm away from the implant surface and operated at medium power or high power for 2 s. The biofilm removal process was imaged using a high speed camera operating at 500 fps. Image analysis was used to calculate the amount of biofilm removed from the high speed images. Scanning electron microscopy was done to visualize the implant surface after cleaning.ResultsCavitation was able to remove biofilm from dental implants. More biofilm was removed at high power. Scanning electron microscopy showed that the implant surface was clean at the points where the cavitation was most intense. High speed imaging showed biofilm removal underneath implant threads, in areas next to the ultrasonic scaler tip.SignificanceA high speed imaging protocol has been developed to visualize and quantify biofilm removal from dental implants in vitro. Cavitation bubbles from dental ultrasonic scalers are able to successfully disrupt biofilm in between implant threads.     

Blood responses to titanium surface with TiO2 nano-mesh structure

Objectives: The goal of this study was to enhance the blood responses to titanium (Ti) surfaces used for dental implant application through the formation of a TiO₂ nano‐mesh surface layer produced by a fast electrochemical anodization treatment. Material and methods: Electrochemical anodization treatments with different anodization currents and temperatures in an alkaline solution were used to create a nano‐mesh oxide layer on polished Ti surface. Surface characterizations of the mesh structure were carried out using thin‐film X‐ray diffractometer, field‐emission scanning electron microscope, and atomic force microscope. The blood responses, including the blood‐clotting ability and platelet adhesion morphology, to the test Ti surfaces were evaluated. The blood‐clotting ability, in terms of optical density of blood, was statistically analyzed using a nonparametric method, Kruskal–Wallis test, for the factor of anodization treatment. Results: A multilayer TiO₂ nano‐mesh structure was rapidly formed on the polished Ti surface using a simple electrochemical anodization treatment in an alkaline solution. The TiO₂ nano‐mesh had an average mesh size between 34 and 93 nm, depending on the anodization current and temperature. The features on the TiO₂ nano‐mesh structure on the anodized Ti surface were of a similar size scale as blood proteins, giving the material better blood clot ability (P<0.05) and improved platelet activation and aggregation as compared with an untreated polished Ti surface. Conclusions: The formation of TiO₂ nano‐mesh on the Ti surfaces was shown to enhance blood responses, which we expect to promote cell growth in the application of dental implants. To cite this article:
Huang H‐H, Chen J‐Y, Lin M‐C, Wang Y‐T, Lee T‐L, Chen L‐K. Blood responses to titanium surface with TiO₂ nano‐mesh structure.
Clin. Oral Impl. Res. 23 , 2012; 379–383.
doi: 10.1111/j.1600‐0501.2010.02152.x     

Finite element stress analysis of Ti-6Al-4V and partially stabilized zirconia dental implant during clenching

Abstract

Objective. The purpose of this paper is to compare the differences in stress between Ti-6Al-4V and PS-ZrO₂ dental implant during clenching and whether these changes are clinically significant to limit the use of zirconia in oral implantology. Materials and methods. The model geometry was derived from position measurements taken from 28 diamond blade cut cross-sections of an average size human adult edentulous mandible and generated using a special sequencing method. Data on anatomical, structural, functional aspects and material properties were obtained from measurements and published data. Ti-6Al-4V and PS-ZrO₂ dental implants were modelled as cylindrical structure with a diameter of 3.26 mm and length of 12.00 mm was placed in the first molar region on the right hemimandible. Results. The analysis revealed an increase of 2–3% in the averaged tensile and compressive stress and an increase of 8% in the averaged Von Mises stress were recorded in the bone–implant interface when PS-ZrO₂ dental implant was used instead of Ti-6Al-4V dental implant. The results also revealed only relatively low levels of stresses were transferred from the implant to the surrounding cortical and cancellous bone, with the majority of the stresses transferred to the cortical bone. Conclusion. Even though high magnitudes of tensile, compressive and Von Mises stresses were recorded on the Ti-6Al-4V and PS-ZrO₂ dental implants and in the surrounding osseous structures, the stresses may not be clinically critical since the mechanical properties of the implant material and the cortical and cancellous bone could withstand stress magnitudes far greater than those recorded in this analysis.