钛片表面粗糙度和氧化膜对成骨细胞黏附影响的体外研究

目的 研究钛片表面粗糙度和氧化膜对成骨细胞黏附的影响,为选择临床种植体的表面处理方法提供依据.方法 250片纯钛钛片分为5组.采用直径分别为108～130 μm(S<,1>组)、216～301 μm(S<,2>组)、356～411 μm(S<,3>组)TiO<,2>砂对钛片表面进行喷砂处理:另外一组钛片采用钛浆喷涂(T...     

Effect of various implant coatings on biological responses in MG63 using cDNA microarray

During the process of bone formation, titanium (Ti) surface is an important factor in the modulation of osteoblastic function. This study was conducted in order to determine the effects of different Ti surfaces on the biological responses of a human osteoblast-like cell line (MG63). MG63 cells were cultured on smooth (S), sandblasted large-grit and acid etching (SLA), hydroxyapatite (HA), hydroxyfluoride (HF), titanium nitrate (TIN), and diamond-like carbon (DLC) Ti. The morphology of these cells were assessed by SEM. The cDNAs prepared from the total RNAs of the MG63 were hybridized into a human cDNA microarray (1152 elements). The appearances of the surfaces observed by SEM were different on each of the six dental substrate types. The SLA and HA surfaces were determined to be rougher than the others. MG63 cells cultured on SLA and HA exhibited cell-matrix interactions. In the expression of genes involved in osseointegration, several genes, including bone morphogenetic protein, cadherin, integrin, and insulin-like growth factors, were upregulated on the different surfaces. Several genes, including fibroblast growth factor receptor 4, Bcl 2-related protein, and collagen, were downregulated on the different surfaces. The attachment and expression of key osteogenic regulatory genes were enhanced by the surface roughness of the dental materials used.     

Determining optimal surface roughness of TiO(2) blasted titanium implant material for attachment, proliferation and differentiation of cells derived from human mandibular alveolar bone

In the complex process of bone formation at the implant-tissue interface, implant surface roughness is an important factor modulating osteoblastic function. In this study, primary cultures of osteoblast-like cells, derived from human mandibular bone, were used. The aim was to examine the effect of varying surface roughness of titanium implant material on cellular attachment, proliferation and differentiation. A recognized method of increasing surface roughness and enlarging the surface area of titanium implants is by blasting with titanium dioxide particles: the four specimen types in the study comprised surfaces which were machine-turned only, or blasted after turning, with 63-90 microm, 106-180 microm, or 180-300 microm TiO(2) particles, respectively. The specimens were analyzed by scanning electron microscopy and confocal laser scanning. The turned samples had the smoothest surfaces: average height deviation (S(a)) of 0.20 microm. The roughest were those blasted with 180-300 microm particles, S(a) value 1.38 microm. Blasting with intermediate particle sizes yielded S(a) values of 0.72 microm and 1.30 microm, respectively. Cell profile areas were measured using a semiautomatic interactive image analyzer. Figures were expressed as percentage of attachment. DNA synthesis was estimated by measuring the amount of [(3)H]-thymidine incorporation into trichloroacetic acid (TCA) insoluble cell precipitates. The specific activity of alkaline phosphatase was assayed using p-nitrophenylphosphate as a substrate. The ability of the cells to synthesize osteocalcin was investigated in serum-free culture medium using the ELSA-OST-NAT immunoradiometric kit. After 3 h of culture, the percentage of cellular attachment did not differ significantly between specimens blasted with 180-300 micromparticles and the turned specimens. All blasted surfaces showed significantly higher [(3)H]-thymidine incorporation than the turned surfaces (P<0.05), with the highest on the surfaces blasted with 180-300 microm particles. Osteocalcin synthesis by the cells in response to stimulation by 1,25(OH)2D3, was also significantly greater (P<0.05) on the surfaces blasted with TiO(2) particles. However, analysis of alkaline phosphatase activity disclosed no significant differences among the four surface modifications. It is concluded that in this cellular model, the proliferation and differentiation of cells derived from human mandibular bone is enhanced by surface roughness of the titanium implant. However, increasing the size of the blasting particles to 300 microm does not further increase the initial attachment of the cells compared to turned surfaces and those blasted with 63-90 microm particles.     

Effects of titanium surfaces blasted with TiO2 particles on the initial attachment of cells derived from human mandibular bone. A scanning electron microscopic and histomorphometric analysis

This study was performed to determine the effect of commercially pure titanium surfaces blasted with TiO2 particles on the biological responses of cells derived from human mandibular bone. The morphology and attachment of those cells were investigated on turned titanium surfaces (control) and surfaces blasted with 45 microns (standard), 45-63 microns, and 63-90 microns TiO2 particles. The surfaces were analyzed in a scanning electron microscope. Based on surface analyses reported elsewhere, the turned samples had the smoothest surfaces and the roughest were those blasted with the largest particles (63-90 microns). The cell profile areas were measured using a semi-automatic interactive image analyzer. The attachment was determined as a ratio of the area of cell profiles and the total micrograph area and was expressed as percentage of attachment. Morphologically, the cells were heterogeneous. In general, the cells had spread well on all titanium surfaces, indicating good attachment to both smooth and rough surfaces. After 1, 3 and 6 h, the percentage of cell attachment did not differ significantly between the surfaces blasted with 63-90 microns and the turned surfaces, but was significantly lower on the surfaces blasted with 45 microns or 45-63 microns particles. After 24 h the surfaces blasted with 63-90 microns particles had a higher rate of cell attachment than all the other surfaces including the controls. It is concluded that attachment and growth of cells originating from human mandibular bone in vitro, are influenced by the micro-texture of the implant surface.     

Histologic comparison of a thermal dual-etched implant surface to machined,TPS, and HA surfaces: bone contact in vivo in rabbits

PURPOSE: To evaluate the bone contact percentage around a proprietary high-temperature dual-etched (DE) implant surface (Osseotite) versus implants with machined, hydroxyapatite (HA), and titanium plasma-sprayed (TPS) surfaces. MATERIALS AND METHODS: Each implant type was placed in rabbit tibiae of the same animal and assessed at 1 to 8 weeks. Histologic sections were prepared and analyzed histomorphometrically. RESULTS: The DE implant surface achieved higher levels of bone contact percentage than the other surfaces. This enhanced contact level was apparent by 3 weeks and seen at all time intervals except 2 weeks, at which machined exceeded the DE mean. In evaluating which surface outscored the others in each individual rabbit, there was a statistically significant confidence for the DE surface (P < .001). The other 3 surfaces failed to show significance, although the numeric scores for the TPS surfaces were below random expectations and the machined scores were slightly above. There was no correlation between degree of roughness and bone contact percentage. DISCUSSION: Arbitrarily roughening the implant surface may not result in a large change in bone conductivity. The specific texture of the DE process yielded more contact, possibly as the result of better fibrin clot retention and growth factor enhancement. CONCLUSIONS: There was no advantage demonstrated in this model to an HA surface over titanium. The bone contact to the rough HA surface scored similarly to that for the TPS surface of similar roughness, and well below that for the DE titanium surface. The DE surface appeared to have an advantage in bone contact percentage, particularly in early healing in a rabbit tibia model.     

Biological responses in osteoblast-like cell line according to thin layer hydroxyapatite coatings on anodized titanium

Several features of the implant surface, such as roughness, topography and composition play a relevant role in implant integration with bone. This study was conducted in order to determine the effects of various thin layer hydroxyapatite (HA) coatings on anodized Ti surfaces on the biological responses of a human osteoblast-like cell line (MG63). MG63 cells were cultured on 100 nm HA (100 nm HA coating on anodized surface), 500-700 nm HA (500-700 nm HA coating on anodized surface), 1 mum HA (1 mum HA coating on anodized surface) and anodize (non-HA coating on anodized surface) Ti. The morphology of these cells was assessed by scanning electron microscopy (SEM). The cDNAs prepared from the total RNAs of the MG63 were hybridized into a human cDNA microarray (1152 elements). The appearances of the surfaces observed by SEM were different on each of the four dental substrate types. MG63 cells cultured on 100 nm HA, 1 mum HA and anodize exhibited cell-matrix interactions. It was 500-700 nm HA surface showing cell-cell interaction. In the expression of genes involved in osseointegration, several genes, including bone morphogenetic protein 2, latent transforming growth factor beta binding protein 1, catenin (cadherin-associated protein), integrin, PDGFRB and GDF-1 growth differentiation factor 1 were up-regulated on the different surfaces. Several genes, including fibroblast growth factor receptor 3, fibroblast growth factor 12 and CD4 were down-regulated on the different surfaces. The attachment and expression of key osteogenic regulatory genes were enhanced by the surface morphology of the dental materials used.     

Characterization of hydroxyapatite films obtained by pulsed-laser deposition on Ti and Ti-6AL-4v substrates.

OBJECTIVES: Pulsed-laser deposition (PLD) is a development process to obtain hydroxyapatite (HA) thin film. It is an alternative to hydroxyapatite deposition techniques usually employed to cover orthopaedic or dental titanium implant surfaces. The aim of this study is to find out the characteristic ratio for Ca/P (1.66) deposit on titanium implant with the PLD process. METHODS: In a preliminary study, the coating parameters of pure and highly crystalline HA on Ti or Ti-6Al-4V substrates were verified by analysing the deposit by Rutherford backscattering spectroscopy (RBS). Ablation parameters to reach a stoichiometric hydroxyapatite composition (ideal Ca/P atomic ratio) and to control the growth of crystalline phases were: 575 degrees C for the substrate temperature, 0.4 mbar H2O vapour pressure in the ablation chamber, the target substrate distance was 40 mm and the deposition time was 120 min. In a second part, the film properties were analysed by means of XRD, SEM, AFM. The coating adhesion of the HA to the substrate was determined with a micro scratch tester. RESULTS: The analysed HA thin films showed a perfect crystallized and textured deposit. Sample observation and surface quality analysis demonstrated a surface roughness and adhesion of the films to the substrates compatible with biological applications. SIGNIFICANCE: These results suggest that pulsed-laser deposition is a suitable technique to obtain crystalline and adherent hydroxyapatite films on Ti or Ti-6Al-4V substrates. The quality of the HA deposit with the PLD process could be an interesting option for coating dental implant.     

Effects of fluoride-modified titanium surfaces on osteoblast proliferation and gene expression

PURPOSE: The objective of this study was to test the hypothesis that fluoride-modified titanium surfaces would enhance osteoblast differentiation. Osteoblast growth on a moderately rough etched fluoride-modified titanium surface (alteration in cellular differentiation) was compared to osteoblast growth on the same surface grit-blasted with titanium dioxide. The potential role of nanometer-level alterations on cell shape and subsequent differentiation was then compared. MATERIALS AND METHODS: Human embryonic palatal mesenchymal (HEPM) cultures were incubated on the respective surfaces for 1, 3, and 7 days, followed by analysis for cell proliferation, alkaline phosphatase (ALP) -specific activity, and mRNA steady-state expression for bone-related genes (ALP, type I collagen, osteocalcin, bone sialoprotein [BSP] II, Cbfa1, and osterix) by real-time polymerase chain reaction (PCR). RESULTS: The different surfaces did not alter the mRNA expression for ALP, type I collagen, osterix, osteocalcin, or BSP II. However, Cbfa1 expression on the fluoride-modified titanium surface was significantly higher (P < .001) at 1 week. The number of cells on this surface was 20% lower than the number of cells on the surface TiO2-blasted with 25-microm particles but not significantly different from the number of cells on the surface TiO2-blasted with 125-microm particles. Cells grown on all the titanium surfaces expressed similar levels of ALP activity. CONCLUSIONS: The results indicated that a fluoride-modified surface topography, in synergy with surface roughness, may have a greater influence on the level of expression of Cbfa1 (a key regulator for osteogenesis) than the unmodified titanium surfaces studied.     

Production of transforming growth factor beta1 and prostaglandin E2 by osteoblast-like cells cultured on titanium surfaces blasted with TiO2 particles

The surface roughness of an implant to which osteoblasts attach may influence endogenous expression of growth factor and cytokines at the implant-tissue interface, modulating the healing process and affecting the quality of bone formation. The present study, using cells derived from human mandibular bone, investigated the effect of varying roughness of titanium surfaces on production of transforming growth factor beta1 (TGF-beta1) and prostaglandin E2 (PGE2). The titanium surfaces were turned (control) and then roughened by blasting with 63-90 micro m, 106-180 micro m or 180-300 micro m TiO2 particles. The cells were cultured onto the surfaces till confluence was achieved. Fresh media were added in the presence or absence of 1,25-dihydroxyvitamin D3[1,25-(OH)2D3], the stimulator of osteogenic differentiation, and aliquots of conditioned cell media were used for assay 24 h later. Cellular morphology was determined by scanning electron microscopy. Cellular production of TGF-beta1 and PGE2 on each surface was assessed by enzyme-linked immunosorbent assay (ELISA) and radioimmunoassay (RIA), respectively, using commercially available kits. All blasted surfaces showed significantly higher production of TGF-beta1 than the turned surfaces (P < 0.05). In response to stimulation by 1,25-(OH)2D3 cellular production of TGF-beta1, was also significantly greater (P < 0.05) on the blasted surfaces than on the turned one. The total amount of PGE2 in the conditioned media was higher than on the turned surfaces in the presence or absence of 1,25-(OH)2D3. There were no significant differences among the three blasted surfaces with respect to production of the local factors. However, we could not show a synergistic effect of surface roughness and vitamin D on the production of both TGF-beta1 and PGE2 using primary cell culture model.     

钛表面形貌和亲水性表面对成骨细胞增殖、分化的影响

目的:通过体外实验研究普通喷砂酸蚀纯钛表面和亲水性喷砂酸蚀纯钛表面对成骨细胞增殖、分化等生物学行为的影响。方法:纯钛片表面分别采用光滑处理(smooth pretreated Ti,PT)、大颗粒喷砂酸蚀表面处理(sand-blasted,large-grit,acid-etched,SLA)及亲水性化学活化大颗粒喷砂酸蚀表面处理(chemically-modified SLA,modSLA/SLActive),在表面接种MC3T3-E1成骨细胞,采用MTT、碱性磷酸酶半定量测试以及茜素红染色检测其对成骨细胞增殖、分化的影响,并采用实时荧光定量PCR检测成骨细胞在不同材料表面骨功能基因表达的差异。应用SAS 9.0软件包对数据进行统计学分析。结果:与光滑钛表面相比,普通喷砂酸蚀钛表面能通过促进ALP、钙基质的分泌和成骨功能基因(Runx2、OSX、OCN和OPN)的表达而显著抑制成骨细胞增殖并促进其分化。在表面粗糙度的基础上增加亲水性,可使这一效应更加明显。结论:表面粗糙度和亲水性是影响成骨细胞生物学行为的重要因素,粗糙钛表面能显著抑制成骨细胞增殖,促进其分化,亲水性的粗糙钛表面促进成骨细胞分化的作用更加显著。     

Attachment and proliferation of human oral fibroblasts to titanium surfaces blasted with TiO2 particles. A scanning electron microscopic and histomorphometric analysis.

The purpose of this study was to determine the effect of c.p. titanium surfaces blasted with TiO2 particles on the biological responses of human gingival fibroblasts (HGF). Fibroblast morphology and attachment were investigated on turned (control) titanium surfaces and those blasted with 45 microns (standard), 45-63 microns, and 63-90 microns TiO2 particles. The specimens were analyzed using a confocal laser scanner and SEM. The cell profile areas were measured using a semiautomatic interactive image analyser. The figures were expressed as percent of attachment. The turned samples had the smoothest surfaces and the roughest were those blasted with 63-90 microns. All TiO2 blasted specimens had homogeneous surfaces. Cells appeared to flatten, spread and form cellular bridges with the adjacent cells. Fibroblasts on the turned titanium surfaces appeared to follow the direction of the fine irregularities on the surface but tended to spread haphazardly on the blasted surfaces. The attachment assays showed no significant difference in the percentage of fibroblast cell attachment on the standard surfaces compared to the turned surfaces. Both surfaces blasted with 45-63 microns or 63-90 microns had significantly (P < 0.05) lower percentages of cell attachment than the control. The surfaces blasted with 63-90 microns particles had the lowest rate of cell attachment. A significant correlation (P < 0.01) was found between the degree of particle size and attachment of fibroblasts after 1-72 h. It is concluded that surface micro-texture influences the attachment and growth of HGF: surfaces blasted with 45 microns TiO2 do not inhibit fibroblast attachment and smooth or finely grooved surfaces could be conducive to cellular attachment.     

Implant Surface Modification Using Laser Guided Coatings: In Vitro Comparison of Mechanical Properties

Purpose: Plasma-sprayed hydroxyapatite (HA)-coated implants show failures along the coating–substrate interface due to poor bond strength. We analyzed HA coatings obtained by pulsed laser deposition (PLD) and compared them to commercially used plasma-sprayed coatings with respect to their bond strength to titanium alloy (Ti-6Al-4V), as well as surface roughness alterations produced by each of the two deposition methods.
Materials and Methods: Twelve titanium alloy disks were plasma-sprayed under commercial implant coating conditions, and 24 titanium alloy disks were coated using PLD. All coatings were characterized by the presence of the different calcium phosphate (CaP) phases. The plasma-sprayed coatings (n = 12) were predominantly HA, and the pulsed laser-deposited coatings were hydroxydyapatite (n = 12) and HA coating with a tetra calcium phosphate (TTCP) phase (n = 12). The surface roughness was analyzed before and after the coating processes to assess roughness changes to the surface by the coatings. The adhesive bond strengths of these coatings to the substrate titanium alloy was tested and compared. Scheffé's test was used to analyze the statistical significance of the data.
Results: The surface roughness alteration following PLD was a decrease of 0.2 μm, whereas following plasma spraying the decrease was 1.0 μm. Bond strengths were as follows [mean (SD) in MPa]: pulsed laser-deposited HA coatings: 68.3 (17.8); pulsed laser-deposited HA with tetra-CaP: 55.2 (21.1); plasma-sprayed HA 17.0 (2.8). The multivariate Scheffé's test revealed that HA coatings obtained by PLD had significantly increased bond strengths compared with the plasma sprayed ones ( p ≤ 0.05).
Conclusions: HA coatings obtained by PLD showed greater adherence to titanium alloy. PLD offers an alternative method to produce thinner coatings with better adherence properties, along with precise control over the deposition process.     

Bone marrow mesenchymal stem cell response to nano-structured oxidized and turned titanium surfaces

Objectives: The aim of this study was to analyse the topographic features of a novel nano‐structured oxidized titanium implant surface and to evaluate its effect on the response of human bone marrow mesenchymal stem cells (BM‐MSC) compared with a traditional turned surface. Methods: The 10 × 10 × 1 mm turned (control) and oxidized (test) titanium samples (P.H.I. s.r.l.) were examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM) and characterized by height, spatial and hybrid roughness parameters at different dimensional ranges of analysis. Primary cultures of BM‐MSC were seeded on titanium samples and cell morphology, adhesion, proliferation and osteogenic differentiation, in terms of alkaline phosphatase activity, osteocalcin synthesis and extracellular matrix mineralization, were evaluated. Results: At SEM and AFM analyses turned samples were grooved, whereas oxidized surfaces showed a more complex micro‐ and nano‐scaled texture, with higher values of roughness parameters. Cell adhesion and osteogenic parameters were greater on oxidized (P<0.05 at least) vs. turned surfaces, whereas the cell proliferation rate was similar on both samples. Conclusions: Although both control and test samples were in the range of average roughness proper of smooth surfaces, they exhibited significantly different topographic properties in terms of height, spatial and, mostly, of hybrid parameters. This different micro‐ and nano‐structure resulted in an enhanced adhesion and differentiation of cells plated onto the oxidized surfaces.     

Surface properties and biocompatibility of acid-etched titanium

The purpose of this study was to evaluate the effects of acid-etched titanium on the biological responses of osteoblast-like MC3T3-E1 cells. Four types of treatments (polishing, sandblasting, concentrated H2SO4 etching, and concentrated H2SO4 etching with vacuum firing) were carried out on the surfaces of commercially pure titanium (cpTi) disks. MC3T3-E1 cells were then cultured on the treated cpTi surfaces. Through surface roughness measurement and SEM analysis, it was found that the acid-etched surfaces showed higher roughness values than the sandblasted ones. Scanning electron microscope analysis showed that the cells on the disks treated with acid-etching and acid-etching with vacuum firing spread as well as the sandblasted ones. There were no significant differences in cell proliferation and collagen production on cpTi among the four different surface treatments. Based on the results of this study, it was concluded that etching with concentrated sulfuric acid was a simple and effective way to roughen the surface of titanium without compromising its biocompatibility.     

Removal of HA and TPS implant coatings and fibroblast attachment on exposed surfaces

The removal of implant coatings may be necessary if rough implant surfaces are exposed subgingivally due to progressive peri-implant bone loss or if they are also supragingivally exposed because of progressive gingival recession, thus facilitating plaque formation and impairing tooth cleaning done at home. The aim of this experimental study was to develop diamond-coated files and rubberized polishers for machine-driven instrumentation of implant cylinders, and present an instrumentation concept for the complete removal of rough titanium plasma spray (TPS) and hydroxylapatite (HA) layers and polishing exposed titanium surfaces. The surface structure and its possible contamination by the instrumentation process was investigated using laser profilometry, scanning electron microscopy, and x-ray fluorescence analysis. The effect of impurities on the growth of human fibroblasts was tested in cell culture. The results show that TPS and HA implant coatings can be removed with the modified implant files. After polishing the exposed titanium surfaces, roughness depths of Rz=4.6 microm (TPS) and Rz=5.7 microm (HA) and, for implant cylinders, 3.4 microm were found. During the instrumentation of implant surfaces, contamination with the material of the instrument must be expected. It was shown that, in principle, growth of human gingival fibroblasts on the instrumented surfaces is possible. The cells were intimately associated with one another and, compared to culture controls, demonstrated good adhesion with strict orientation to the microstructure of the scoring left by instrumentation. The biological consequences and mechanisms of cell adhesion on instrumented surfaces require further investigation.     

Cleaning and heat-treatment effects on unalloyed titanium implant surfaces

This study tested the following hypotheses: (1) acid-cleaned and passivated unalloyed titanium implants have higher surface energies (which are considered desirable for bone implants) than ethanol-cleaned titanium; (2) higher temperatures of heat treatment of unalloyed titanium result in higher surface energies; and (3) these changes can be related to changes in surface composition and roughness. Thus, unalloyed titanium specimens were either acid-cleaned and passivated (CP) or ethanol-cleaned (Et). Each set was then divided into 3 groups and heat-treated for 1 hour at 316 degrees C (600 degrees F), 427 degrees C (800 degrees F), and 538 degrees C (1,000 degrees F), respectively. Surface roughness values for each of these groups were determined using atomic force microscopy, while surface compositions were determined using Auger electron, x-ray photoelectron, and Raman spectroscopic techniques. Surface energies were estimated using a 2-liquid geometric mean technique and correlated with surface roughness, elemental composition, and elemental thickness. The CP surfaces were slightly rougher than the Et specimens, which had greater oxide thickness and hydrocarbon presence. The surface oxides were composed of TiO2, Ti2O3, and possibly titanium peroxide; those heat-treated at 427 degrees C or above were crystalline. The CP specimens had carbonaceous coverage that was of a different composition from that on Et specimens. The CP specimens had significantly higher surface energies, which showed statistically significant correlations with oxide thickness and carbonaceous presence. In conclusion, ethanol cleaning of unalloyed titanium dental implants may not provide optimal surface properties when compared to cleaning with phosphoric acid followed by nitric acid passivation.     

钛片表面粗糙度和氧化膜对成骨细胞增殖和分化的影响

目的：研究钛片表面粗糙度和氧化膜对成骨细胞增殖和分化的影响,为种植体表面处理提供理论依据。方法：采用粒度分别为108～130 μm(S1)、216～301 μm(S2)和356～411 μm(S3)的二氧化钛颗粒对纯钛钛片表面进行喷砂处理,钛浆喷涂(titanium-sprayed plasma, TPS)表面处理组由Straumman 公司提供,600目砂纸打磨组(S0)作为对照组,在钛片表面进行成骨细胞培养。采用表面轮廓测量仪测量其表面粗糙度,电子探针(electron microprobe)测定钛片表面氧化膜结构。分别在1、3、5及7 d时,采用四锉盐比色(MTT)法检测不同处理表面对成骨细胞增殖(OD值)的影响;通过碱性磷酸酶活性(ALP)及骨钙素分泌(OC)检测比较不同处理的表面对成骨细胞分化的影响。采用SPSS12.0软件包对数据进行单因素方差分析。结果：S0 、S1 、S2 、S3 和TPS组表面粗糙度由0.372 μm至5.239 μm递增;喷砂组钛片表面氧化膜结构完整、连续;粗糙表面比光滑表面更利于成骨细胞增殖和分化。喷砂表面粗糙度越高,越利于成骨细胞增殖和分化。S3组成骨细胞增殖和分化优于TPS组。结论：表面粗糙度较高的喷砂表面,更利于成骨细胞增殖和分化。     

Bone healing capacity of titanium plasma‐sprayed and hydroxylapatite‐coated oral implants

The influence of surface quality, in particular surface topography and implant material, was evaluated by inserting titanium‐ and hydroxylapatite plasma‐sprayed coated implants into the maxilla of 10 goats. Three types of plasma‐spray coatings were applied to tapered, screw shaped implants; titanium plasma‐spray coating (TPS), titanium plasma‐spray coating with additional acid passivation (TPSA) and a bilayered coating (TPS/HA) consisting of titanium plasma‐spray coating (TPS) and a hydroxylapatite part (HA). In addition, as machined implants (TIM) were used as control. A total of 40 implants were inserted according a balanced split plot design. At the end of a 3‐month healing period, it appeared that 5 implants (2 TPS, 1 TPSA, 1 TPS/HA and 1 TiM) were lost. Histological examination revealed a stronger bone response to TPS/HA coated implants. Even the TPS/HA coated implants induced bone formation on the part of the implant inserted into the sinus. No signs of delamination of the TPS coatings were visible. The HA part of the dual coating showed signs of degradation. Histomorphometrical analysis confirmed these findings. A significant difference in bone contact ( P <0.05) was measured between the TPS/HA coated implants and the other types of implants. Linear regression ( r >0.2) showed no correlation between the inscrew values at the base line and the bone contact measurements 3 months after healing. On the basis of these results, we can conclude that the chemical composition of the HA coating has a positive influence on the bone reaction. The influence of roughness is less evident.     

The effects of titanium nitride-coating on the topographic and biological features of TPS implant surfaces

Objectives

Titanium nitride (TiN) coating has been proposed as an adjunctive surface treatment aimed to increase the physico-mechanical and aesthetic properties of dental implants. In this study we investigated the surface characteristics of TiN-coated titanium plasma sprayed (TiN-TPS) and uncoated titanium plasma sprayed (TPS) surfaces and their biological features towards both primary human bone marrow mesenchymal stem cells (BM-MSC) and bacterial cultures.

Methods

15 mm × 1 mm TPS and TiN-TPS disks (P.H.I. s.r.l., San Vittore Olona, Milano, Italy) were topographically analysed by confocal optical profilometry. Primary human BM-MSC were obtained from healthy donors, isolated and expanded. Cells were seeded on the titanium disks and cell adhesion, proliferation, protein synthesis and osteoblastic differentiation in terms of alkaline phosphatase activity, osteocalcin synthesis and extracellular mineralization, were evaluated. Furthermore, adhesion and proliferation of Streptococcus pyogenes and Streptococcus sanguinis on both surfaces were also analysed.

Results

TiN-TPS disks showed a decreased roughness (about 50%, p < 0.05) and a decreased bacterial adhesion and proliferation compared to TPS ones. No difference (p > 0.05) in terms of BM-MSC adhesion, proliferation and osteoblastic differentiation between TPS and TiN-TPS surfaces was found.

Conclusions

TiN coating showed to modify the topographical characteristics of TPS titanium surfaces and to significantly reduce bacterial adhesion and proliferation, although maintaining their biological affinity towards bone cell precursors.