Clinical evaluation of non-surgical cleaning modalities on titanium dental implants during maintenance care: a 1-year follow-up on prosthodontic superstructures.

OBJECTIVES: To investigate tissue health around implants with newly attached superstructures over 12 months of preventive maintenance appointments and instrumentation when necessary. MATERIAL AND METHODS: In a randomized, split-mouth study 32 implants (8 participants with 4 implants each) received followed-up care every 3 months after superstructure attachment. Implants and superstructures were randomly assigned to four treatment groups and treated if necessary: (1) titanium curettes (TC), (2) stainless steel ultrasonic tip (PS), (3) erythritol air-polishing powder (EP), or (4) rubber cup polishing (CON). Probing depths (PDs), bleeding on probing (BOP), modified gingival (mucosal) bleeding index (GBI) around implants, and full-mouth Plaque Control Record (PCR) were measured every 3 months. Clinical attachment levels (CALs) and height of keratinized mucosa (KM)/gingival margins (GMs) for implants/teeth and PD, BOP, and GBI for teeth were documented at baseline, 6 months, and 12 months. Matrix metalloproteinase 8 (MMP-8) and periopathogens were measured at baseline and 12 months. RESULTS: Participants exhibited minimal signs of periodontal inflammation with statistically significant PD improvement (3.0 ± 0.2 to 2.8 ± 0.3 mm; p = 0.022) and overall CAL (4.3 ± 0.8 to 4.0 ± 0.7 mm; p = 0.048) after 1 year. Implants showed no statistically significant differences (p > 0.05) between or within groups at baseline or 12 months for any parameter, except MMP-8 decreased significantly for PS (14.50 ± 17.58 to 4.63 ± 7.56 ng; p = 0.044), and after 12 months, PCR showed a significant difference between TC and PS (p = 0.018). CONCLUSIONS: Treatment was necessary as inflammation was observed around newly placed superstructures within the first year of maintenance care. All tested treatment modalities yielded comparable clinical improvements. CLINICAL RELEVANCE: Early assessment and diagnosis of mucositis and regular maintenance can promote long-lasting implant health.

Clinical and laboratory evaluation of the effects of different treatment modalities on titanium healing caps: a randomized, controlled clinical trial.

OBJECTIVES: The objective of this study is to evaluate the effects of treatment modalities on titanium surface characteristics and surrounding tissues. MATERIALS AND METHODS: Eighteen participants each had four titanium healing caps (HC) attached to four newly inserted implants. After healing, each HC was randomly assigned to either (1) titanium curettes (TC), (2) stainless steel ultrasonic tip (PS), (3) erythritol air-polishing powder (EP), or (4) only rubber cup polishing (CON). Probing depths (PD), bleeding on probing (BOP), matrix metalloproteinase 8 (MMP-8), and periopathogens were recorded before and 3 months following instrumentation. After final assessments, HCs were removed, cleaned, and subjected to (a) bacterial colonization (Streptococcus gordonii, 24 h; mixed culture, 24 h) and (b) gingival fibroblasts (5 days). HC surfaces were analyzed with a scanning electron microscope (SEM). RESULTS: No significant differences between the groups were evident before or after instrumentation for PD and BOP (except TC showed a significant decrease in PD; p = 0.049). MMP-8 levels and bacterial loads were always very low. MMP-8 decreased further after instrumentation, while bacteria levels showed no change. No significant differences (p > 0.05) were evident in bacterial colonization or fibroblast attachment. A comparison of the overall mean SEM surface roughness scores showed a significant difference between all groups (p < 0.0001) with the lowest roughness after EP. CONCLUSIONS: All treatments performed yielded comparable outcomes and may be implemented safely. CLINICAL RELEVANCE: Clinicians may fear implant surface damage, but all instrumentation types are safe and non-damaging. They can be implemented as needed upon considering the presence of staining and soft and hard deposits.

In vitro biological outcome of laser application for modification or processing of titanium dental implants.

There are numerous functions for laser in modern implant dentistry including surface treatment, surface coating, and implant manufacturing. As laser application may potentially improve osseointegration of dental implants, we systematically reviewed the literature for in vitro biological responses to laser-modified or processed titanium dental implants. The literature was searched in PubMed, ISI Web, and Scopus, using keywords "titanium dental implants," "laser," "biocompatibility," and their synonyms. After screening the 136 references obtained, 28 articles met the inclusion criteria. We found that Nd:YAG laser was the most commonly used lasers in the treatment or processing of titanium dental implants. Most of the experiments used cell attachment and cell proliferation to investigate bioresponses of the implants. The most commonly used cells in these assays were osteoblast-like cells. Only one study was conducted in stem cells. These in vitro studies reported higher biocompatibility in laser-modified titanium implants. It seems that laser radiation plays a vital role in cell response to dental implants; however, it is necessary to accomplish more studies using different laser types and parameters on various cells to offer a more conclusive result.

Effects of restraint stress and surface treatments on the stability of titanium dental implant osseointegration in dogs: An in vivo comparative study.

Objectives: This study was aimed at assessing the effects of restraint stress and sandblasting; sandblasting with acid etching; Er-Cr: YSGG laser treatment; and propolis coating of implant surfaces on the implant stability quotient (ISQ) of grade 4 titanium dental implant osseointegration in model dogs. Methods: A total of forty-eight CPTi dental implants were divided into four groups according to surface treatment: group A: sandblasting with acid etching; group B: sandblasting with Al2O3; group C: Er-Cr: YSGG laser; and group D: propolis coating. Sixteen male dogs of local breed,1-1.5 years of age, weighing 22 ± 3 kg, were divided into two main groups (n-8 dogs each): a non-stressed group (group I) and stressed group (group II). Each of these groups is further divided into four implant groups per surface treatment, A, B, C, and D (two dogs per implant group), each dog has three implants. The ISQ was tested at 0 (baseline), 14, and 90 days with a noninvasive EasyCheck® device. Serum cortisol in the stressed and non-stressed groups was analyzed at 0, 15, 30, 45, 60, 75, and 90 days with a canine cortisol ELISA kit. The data were statistically analyzed with one-way analysis of variance and Tukey's post hoc test at a 0.05 level of significance. Results: For implant stability quotient (ISQ), sandblasting in the non-stressed (group I) had the highest mean value (88.0) at 90-days, whereas sandblasting with acid etching at 14-days had the lowest mean value (82.6). Sandblasting in the stressed (group II) had the highest mean value (88.3) at 90-days, whereas the laser surface treatment had the lowest mean value (72.00) at 14-days. Serum cortisol (ng/µl) at 90 days (143.10 and 195.33 for non-stressed and stressed groups respectively), was significantly higher than other time intervals (P < 0.05). Conclusions: The ISQ was dependent on surface treatment, and was higher with sandblasting than the other treatments in the stressed and non-stressed groups at 90 days. For all surface-treated implants, the stressed group had significantly higher serum cortisol levels than the non-stressed group.

The Effects of Titanium Dioxide Nanoparticles on Osteoblasts Mineralization: A Comparison between 2D and 3D Cell Culture Models.

Although several studies assess the biological effects of micro and titanium dioxide nanoparticles (TiO2 NPs), the literature shows controversial results regarding their effect on bone cell behavior. Studies on the effects of nanoparticles on mammalian cells on two-dimensional (2D) cell cultures display several disadvantages, such as changes in cell morphology, function, and metabolism and fewer cell-cell contacts. This highlights the need to explore the effects of TiO2 NPs in more complex 3D environments, to better mimic the bone microenvironment. This study aims to compare the differentiation and mineralized matrix production of human osteoblasts SAOS-2 in a monolayer or 3D models after exposure to different concentrations of TiO2 NPs. Nanoparticles were characterized, and their internalization and effects on the SAOS-2 monolayer and 3D spheroid cells were evaluated with morphological analysis. The mineralization of human osteoblasts upon exposure to TiO2 NPs was evaluated by alizarin red staining, demonstrating a dose-dependent increase in mineralized matrix in human primary osteoblasts and SAOS-2 both in the monolayer and 3D models. Furthermore, our results reveal that, after high exposure to TiO2 NPs, the dose-dependent increase in the bone mineralized matrix in the 3D cells model is higher than in the 2D culture, showing a promising model to test the effect on bone osteointegration.

Application of Lyophilized Gene-Delivery Formulations to Dental Implant Surfaces: Non-Cariogenic Lyoprotectant Preserves Transfection Activity of Polyplexes Long-Term.

Titanium is the metal of choice for dental implants because of its biocompatibility and ability to merge with human bone tissue. Despite the great success rate of dental implants, early and late complications occur. Coating titanium dental implant surfaces with polyethyleneimine (PEI)-plasmid DNA (pDNA) polyplexes improve osseointegration by generating therapeutic protein expression at the implantation site. Lyophilization is an approach for stabilizing polyplexes and extending their shelf life; however, most lyoprotectants are sugars that can aid bacterial growth in the peri-implant environment. In our research, we coated titanium surfaces with polyplex solutions containing varying amounts of lyoprotectants. We used two common lyoprotectants (sucrose and polyvinylpyrrolidone K30) and showed for the first time that sucralose (a sucrose derivative used as an artificial sweetener) might act as a lyoprotectant for polyplex solutions. Human embryonic kidney (HEK) 293T cells were used to quantify the transfection efficiency and cytotoxicity of the polyplex/lyoprotectant formulations coating titanium surfaces. Polyplexes that were lyophilized in the presence of a lyoprotectant displayed both preserved particle size and high transfection efficiencies. Polyplexes lyophilized in 2% sucralose have maintained transfection efficacy for three years. These findings suggest that modifying dental implants with lyophilized polyplexes might improve their success rate in the clinic.

Preventing Peri-implantitis: The Quest for a Next Generation of Titanium Dental Implants.

Titanium and its alloys are frequently the biomaterial of choice for dental implant applications. Although titanium dental implants have been utilized for decades, there are yet unresolved issues pertaining to implant failure. Dental implant failure can arise either through wear and fatigue of the implant itself or peri-implant disease and subsequent host inflammation. In the present report, we provide a comprehensive review of titanium and its alloys in the context of dental implant material, and how surface properties influence the rate of bacterial colonization and peri-implant disease. Details are provided on the various periodontal pathogens implicated in peri-implantitis, their adhesive behavior, and how this relationship is governed by the implant surface properties. Issues of osteointegration and immunomodulation are also discussed in relation to titanium dental implants. Some impediments in the commercial translation for a novel titanium-based dental implant from "bench to bedside" are discussed. Numerous in vitro studies on novel materials, processing techniques, and methodologies performed on dental implants have been highlighted. The present report review that comprehensively compares the in vitro, in vivo, and clinical studies of titanium and its alloys for dental implants.

Role of chitosan in titanium coatings. trends and new generations of coatings.

Survival studies of dental implants currently reach high figures. However, considering that the recipients are middle-aged individuals with associated pathologies, research is focused on achieving bioactive surfaces that ensure osseointegration. Chitosan is a biocompatible, degradable polysaccharide with antimicrobial and anti-inflammatory properties, capable of inducing increased growth and fixation of osteoblasts around chitosan-coated titanium. Certain chemical modifications to its structure have been shown to enhance its antibacterial activity and osteoinductive properties and it is generally believed that chitosan-coated dental implants may have enhanced osseointegration capabilities and are likely to become a commercial option in the future. Our review provided an overview of the current concepts and theories of osseointegration and current titanium dental implant surfaces and coatings, with a special focus on the in vivo investigation of chitosan-coated implants and a current perspective on the future of titanium dental implant coatings.

Effectiveness of biomolecule-based bioactive surfaces, on os-seointegration of titanium dental implants: A systematic review and meta-analysis of in vivo studies.

Titanium and alloy osseointegrated implants are used to replace missing teeth; however, some fail and are removed. Modifications of the implant surface with biologically active substances have been proposed. MEDLINE [via Pubmed], Embase and Web of Science were searched with the terms "titanium dental implants", "surface properties", "bioactive surface modifications", "biomolecules", "BMP", "antibacterial agent", "peptide", "collagen", "grown factor", "osseointegration", "bone apposition", "osteogenic", "osteogenesis", "new bone formation", "bone to implant contact", "bone regeneration" and "in vivo studies", until May 2022. A total of 10,697 references were iden-tified and 26 were included to analyze 1,109 implants, with follow-ups from 2 to 84 weeks. The ARRIVE guidelines and the SYRCLE tool were used to evaluate the methodology and scientific evidence. A meta-analysis was performed (RevMan 2020 software, Cochane Collaboration) with random effects that evaluated BIC at 4 weeks, with subgroups for the different coatings. The heterogeneity of the pooled studies was very high (95% CI, I2 = 99%). The subgroup of BMPs was the most favorable to coating. Surface modification of Ti implants by organic bioactive molecules seems to favor osseointegration in the early stages of healing, but long-term studies are necessary to corroborate the results of the experimental studies.

Effectiveness of Antibacterial Surfaces in Osseointegration of Titanium Dental Implants: A Systematic Review.

Titanium (Ti) dental implant failure as a result of infection has been established at 40%, being regarded as one of the most habitual and untreatable problems. Current research is focused on the design of new surfaces that can generate long-lasting, infection-free osseointegration. The purpose of our study was to assess studies on Ti implants coated with different antibacterial surfaces, assessing their osseointegration. The PubMed, Web of Science and Scopus databases were electronically searched for in vivo studies up to December 2020, selecting six studies that met the inclusion criteria. The quality of the selected studies was assessed using the ARRIVE (Animal Research: Reporting of In Vivo Experiments) criteria and Systematic Review Center for Laboratory animal Experimentation's (SYRCLE's) risk of bias tool. Although all the included studies, proved greater osseointegration capacity of the different antibacterial surfaces studied, the methodological quality and experimental models used in some of them make it difficult to draw predictable conclusions. Because of the foregoing, we recommend caution when interpreting the results obtained.

Effects of photofunctionalization on early osseointegration of titanium dental implants in the maxillary posterior region: a randomized double-blinded clinical trial.

BACKGROUND: This study aimed to investigate the effects of ultraviolet (UV) photofunctionalization on the stability of implants during the early phase in the posterior region of the maxilla. The study was a randomized double-blinded clinical trial. Half of the participants received conventional commercial implants while the other half received UV-irradiated implants. The surgical sites were classified into three bone quality groups (II, III, IV) based on the grayscale value measured on cone-beam computed tomography. The values obtained from resonance frequency analysis were recorded immediately after implant placement and at 4 weeks and at 4 months postoperatively. The marginal bone level of the implants was evaluated using periapical radiographs at 4 weeks, 4 months, and 1 year postoperatively. RESULTS: Fifty-seven implants placed in 34 participants were analyzed in this study. In group III, significant differences were observed in terms of the differences of resonance frequency analysis values at 4 weeks (p = 0.004) and 4 months (p = 0.017) postoperatively. In group II, the UV-treated group showed significantly lesser bone loss at 4 weeks post-operatively (p = 0.037). CONCLUSIONS: Within the limitation of the present study, we concluded that UV surface treatment on implants may increase the initial stability in the region of the maxilla with poor bone quality.

Zirconia vs. Titanium Dental Implants: Primary Stability In-Vitro Analysis.

The present experimental trial uses two types of dental implants, one made of titanium (Ti6Al4V) and the other one of zirconia (ZrO2), but both of identical design, to compare their stability and micro-movements values under load. One of each type of implant (n = 42) was placed into 21 cow ribs, recording the insertion torque and the resonance frequency using a specific transducer. Subsequently, a prosthetic crown made of PMMA was screwed onto each of the implants in the sample. They were then subjected to a static compression load on the vestibular cusp of the crown. The resulting micromovements were measured. The zirconia implants obtained a higher mean of both IT and RFA when compared with those of titanium, with statistically significant differences in both cases (p = 0.0483 and p = 0.0296). However, the micromovement values when load was applied were very similar for both types, with the differences between them (p = 0.3867) not found to be statistically significant. The results show that zirconia implants have higher implant stability values than titanium implants. However, the fact that there are no differences in micromobility values implies that caution should be exercised when applying clinical protocols for zirconia based on RFA, which only has evidence for titanium.

Evaluation of osseintegration between traditional and modified hydrophilic titanium dental implants - Systematic analysis.

The aim of the study was to conduct a systematic review to access the osseointegration between traditional and modified Hydrophilic Titanium Dental Implants for period of 10 years. PUBMed articles were searched from last ten years up to 15/12/2019 from which 24 studies included in this review. This systematic review compiles the data about osseintegration in hydrophilic titanium implants in human trials. It sheds light on the mechanism of integration of hydrophilic surfaces and numeric data to support the purpose of the review.

Elevated Systemic L-Kynurenine/L-Tryptophan Ratio and Increased IL-1 Beta and Chemokine (CX3CL1, MCP-1) Proinflammatory Mediators in Patients with Long-Term Titanium Dental Implants.

Titanium is the mean biocompatible metal found in dental titanium alloys (Ti-6Al-4V). The safety of certain dental biomaterial amalgams has been questioned in patients. The levels of several systemic cytokines (interleukin (IL)-1 beta, IL-4: pg/mL) and chemokines (monocyte chemoattractant protein-1 (MCP-1), soluble fractalkine (CX3CL1: pg/mL) were determined using ELISA and compared between these study groups. The study included 30 controls without dental materials (cont), 57 patients with long-term titanium dental implants plus amalgams (A + I group) as well as 55 patients with long-term dental amalgam alone (A group). All patients (except controls) have had dental titanium implants (Ti-6Al-4V) and/or amalgams for at least 10 years (average: 15 years). We evaluated whether systemic levels of cytokines/chemokines, kyn/L-trp ratio and aromatic amino acid levels (HPLC: mM/L, Phe, L-Trp, His, Treo) could be altered in patients with long-term dental titanium and/or amalgams. These systemic markers were evaluated in 142 patients. The A + I group had higher L-Kynurenine/L-Tryptophan ratios than patients with long-term dental amalgam fillings alone (A). In addition, levels of IL-1 Beta cytokine, CX3CL1 and MCP-1 chemokines were higher in the A + I group than in the A group (A). The increased L-kyn/L-trp ratio and MCP-1 and fractalkine receptor (CX3CR1) elevations could suggest enhanced chemotactic responses by these chemokines in the A + I group.

In-vitro and in-vivo, cytotoxicity evaluation of cast functionally graded biomaterials for dental implantology.

An innovative technique of casting the titanium implant alloys and its calcium phosphate coating using centrifugal casting method was proposed in the current study. This one-step, self-coating technique results in formation of functionally graded biomaterials (FGBMs) of calcium phosphate/Titanium alloys. Two groups of samples (Group 1 and Group 2) were prepared utilizing self-coated titanium­niobium (Ti-6Al-7Nb) and titanium- vanadium (Ti-6Al-4V) alloys respectively. The cast samples were then prepared for in-vitro cytocompatibility evaluation, in-vivo systemic toxicity and osseointegration evaluation. Cytocompatibility was examined in-vitro on human bone osteosarcoma cells (Saos-2). In-vivo surgical implantation of the samples in the mandible of the experimental dogs was correspondingly implemented. Tests for systemic toxicity, X-ray images, Dual Energy X-ray Absorptiometry (DEXA) and histopathological analysis were obtained for each dog's mandible sample. In-vitro cytocompatibility studies revealed high cytocompatibility of Group 2 in comparison to Group 1. In-vivo results proved safety of Group 2 as regards to systemic toxicity. On the other hand, results of the X-ray images, DEXA and histopathological analysis revealed comparable osseointegration potential of both groups. These results suggest the use of Group2-FGBMs in dental implant manufacturing and prove that FGBMs prepared by centrifugal casting as self-coated implants have good biocompatibility and osseointegration capability.

Synergistic Effect of Cold Plasma Treatment and RGD Peptide Coating on Cell Proliferation over Titanium Surfaces.

The aim of this study was to investigate the synergistic effect of cold atmospheric plasma (CAP) treatment and RGD peptide coating for enhancing cellular attachment and proliferation over titanium (Ti) surfaces. The surface structure of CAP-treated and RGD peptide-coated Ti discs were characterized by contact angle goniometer and atomic force microscopy. The effect of such surface modification on human bone marrow derived mesenchymal stem cells (hMSCs) adhesion and proliferation was assessed by cell proliferation and DNA content assays. Besides, hMSCs' adhesion and morphology on surface modified Ti discs were observed via fluorescent and scanning electron microscopy. RGD peptide coating following CAP treatment significantly enhanced cellular adhesion and proliferation among untreated, CAP-treated and RGD peptide-coated Ti discs. The treatment of Ti surfaces with CAP may contribute to improved RGD peptide coating, which enables increased cellular integrations with the Ti surfaces.

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. METHODS: Retrieval analysis: Seven early- stage failed implants with five of them connected to healing abutments (HAs), and ten late- stage failed retrievals were subjected to surface analysis. Bacteria immersion test: Three dental implants each were immersed in polycultures containing (i) early colonizers (Streptococcus mutans, S. salivarius, S. sanguinis) (ii) late colonizers (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans). The implants were immersed for 30 days to simulate the healing period and bacterial biofilm adhesion. Optical microscope, x-ray photoelectron spectroscopy (XPS), and electrochemical test were performed to analyze the surface- morphology, chemistry, and potential respectively. RESULTS: Early colonizers inflicted surface morphological damage (discoloration and pitting). Even though, XPS detected thinner oxide layer in 2/3 early retrievals, XPS and electrochemical tests illustrated that the TiO2 layer was intact in HAs, and in DI post- immersion. Late colonizers also caused similar morphological damage (discoloration and pitting), while mechanical wear was evident with scratches, cracks, and mechanical fracture observed in late-stage retrievals. XPS indicated thinner oxide layer in late-stage retrievals (3/4), and in DI post-immersion in late colonizers. This was reflected in electrochemical test results post-immersion but not in the late-stage retrievals, which suggested an intact surface with corrosion resistance. SIGNIFICANCE: This study concluded that bacteria could negatively affect implant surface with late colonizers demonstrating more pronounced damage on the surface morphology and chemistry.

Superior biofunctionality of dental implant fixtures uniformly coated with durable bioglass films by magnetron sputtering.

Bioactive glasses are currently considered the suitable candidates to stir the quest for a new generation of osseous implants with superior biological/functional performance. In congruence with this vision, this contribution aims to introduce a reliable technological recipe for coating fairly complex 3D-shaped implants (e.g. dental screws) with uniform and mechanical resistant bioactive glass films by the radio-frequency magnetron sputtering method. The mechanical reliability of the bioactive glass films applied to real Ti dental implant fixtures has been evaluated by a procedure comprised of "cold" implantation in pig mandibular bone from a dead animal, followed by immediate tension-free extraction tests. The effects of the complex mechanical strains occurring during implantation were analysed by scanning electron microscopy coupled with electron dispersive spectroscopy. Extensive biocompatibility assays (MTS, immunofluorescence, Western blot) revealed that the bioactive glass films stimulated strong cellular adhesion and proliferation of human dental pulp stem cells, without promoting their differentiation. The ability of the implant coatings to conserve a healthy stem cell pool is promising to further endorse the fabrication of new osseointegration implant designs with extended lifetime.

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

OBJECTIVES: To identify the TiO2 phases of the root surface of commercially available titanium dental implants, subjected to various surface treatments. METHODS: The 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 (514.5nm wavelength) and a 100 µm × 100 µm sampling area at two randomly selected sites. RESULTS: The 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. SIGNIFICANCE: Great 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.

Adult stem cells properties in terms of commitment, aging and biological safety of grit-blasted and Acid-etched ti dental implants surfaces.

Titanium (Ti) is one of the most widely used biomaterials for manufacturing dental implants. The implant surface properties strongly influence osseointegration. The aim of the present study was to in vitro investigate the characteristics of Ti dental implants in terms of mutagenicity, hemocompatibility, biocompatibility, osteoinductivity and biological safety. The Ames test was used to test the mutagenicity of the Ti dental implants, and the hemolysis assay for evaluating their hemocompatibility. Human adipose - derived stem cells (ADSCs) were then seeded onto these implants in order to evaluate their cytotoxicity. Gene expression analyzing with real-time PCR was carried out to investigate the osteoinductivity of the biomaterials. Finally, the genetic stability of the cells cultured onto dental implants was determined by karyotyping. Our results demonstrated that Ti dental implants are not mutagenic, do not cause hemolysis, and are biocompatible. The MTT assay revealed that ADSCs, seeded on Ti dental implants, proliferate up to 30 days in culture. Moreover, ADSCs loaded on Ti dental implants show a substantial expression of some osteoblast specific markers, such as COL1A1, OPN, ALPL, and RUNX2, as well as chromosomal stability after 30 days of culture in a medium without osteogenic factors. In conclusion, the grit-blasted and acid-etched treatment seems to favor the adhesion and proliferation of ADSCs and improve the osteoinductivity of Ti dental implant surfaces.