Surface Of Dental Implants Research Articles

The Effectiveness of Cold Atmospheric Plasma (CAP) on Bacterial Reduction in Dental Implants: A Systematic Review.

The emergence of dental implants has revolutionized the management of tooth loss. However, the placement of clinical implants exposes them to complex oral environment and numerous microscopic entities, such as bacteria. Cold atmospheric plasma (CAP) is often used to treat the surfaces of dental implants, which alters morphological features and effectively reduces bacterial load. This systematic review aims to assess the existing literature on the bactericidal properties of CAP when used on various kinds of dental implant surfaces. An in-depth examination of MEDLINE/PubMed and EMBASE was performed to identify relevant studies, with the most recent search conducted in May 2023. Studies were selected based on their exploration of CAP's effects on dental implants compared to control groups, focusing on CAP's bactericidal efficacy. However, studies that lacked a control group or that failed to measure bactericidal effects were excluded. After applying the selection criteria, 15 studies were ultimately included in the systematic review. The collected data suggest that CAP can effectively reduce bacterial loads on dental implant surfaces, including pathogens like Streptococcus mitis and Staphylococcus aureus. Furthermore, CAP appears to combat biofilms and plaques that are key contributors to periimplantitis. CAP emerges as a promising treatment option, exhibiting significant bactericidal activity on dental implant surfaces. CAP can decrease the rates of bacterial biofilm and plaque formation, leading to improved outcomes for dental implant patients.

A programmed surface on dental implants sequentially initiates bacteriostasis and osseointegration.

Osteogenesis surrounding dental implants is initiated by a series of early physiological events, including the inflammatory response. However, the persistence of an anti-infection surface often results in compromised histocompatibility and osseointegration. Here, we presented a programmed surface containing both silver nanoparticles (AgNPs) and silver ions (Ag+) with a heterogeneous structure and time-dependent functionalities. The AgNPs were located at the surface of the heparin-chitosan polyelectrolyte coating (PEM), whereas Ag+ was distributed at both the surface and inside of the coating under optimized conditions (pH=4). The optimized coating (Ag-4) exhibited potent bactericidal activity at the early stage (12 and 24h after inoculation) and a sustained antibacterial efficacy in the subsequent stage (one or two weeks), as it gradually depleted. Furthermore, compared to coatings with sustained high silver concentrations in bacteria-cell coculture experiments, the degradable Ag-4 coating demonstrated improved cytocompatibility, better cell viability, and morphology over time. At a later stage (within one month), the in vivo test revealed that Ag-4-coated titanium had superior histocompatibility and osteogenesis outcomes compared to bare titanium in a bacteria-exposed environment. The programmed surface of dental implants presented in this study offers innovative ideas for sequential antibacterial effects and osseointegration.

Ultrastructural studies on implants failure with immediate or late loading

Objectives. The purpose of the present study was to evaluate by scanning electron microscope (SEM) and energy dispersive spectrophotometry (EDS), the degree of bone mineralization of the tissues on the surface of failure dental implants with immediate or late loading. Materials and method. In the study, 8 dental explants from 8 clinically healthy, non-smoking patients were taken. All implants were inserted by the same dental surgeon, 4 of them were immediate loaded and 4 were late prosthetically loaded by the same dentist. The ablation of the implants was performed as atraumatically as possible and they were collected in sterile containers and sent to the BIOMAT Research Center, where they were subjected to SEM and EDS analyses. The ratios between the chemical elements calcium and nitrogen (Ca/N), phosphorus and nitrogen (P/N), respectively calcium and phosphorus (Ca/P) were calculated for each of the 8 samples and were statistically analyzed. Results. If we compare the degree of coverage of the implants with bone tissue in different phases of mineralization, we find that the bone structures occupy a larger surface area of the implants in the cases with immediate loading compared to the cases with late loading. Thus, out of 4 immediately loaded implants, 2 were completely covered, one showed very little exposed areas, and the fourth showed alternating covered and uncovered areas. Regarding the late loaded implants, three showed alternation between covered and uncovered areas and only one was completely covered with bone. Conclusions. The degree of coverage of the explants with bone tissue was better represented for the immediate loading cases. The degree of mineralization of the bone tissue covering the explants was higher for cases with immediate loading. To confirm the obtained results, it is necessary to expand the study on larger batches of samples.

РОЛЬ ХОЛОДНОЙ АТМОСФЕРНОЙ ПЛАЗМЫ НА СОВРЕМЕННОМ ЭТАПЕ РАЗВИТИЯ ОТЕЧЕСТВЕННОЙ СТОМАТОЛОГИИ

Dental implants are often used in everyday clinical practice. The micro-nanotopography of the surface dental implants used is formed by - mechanical processing, sandblasting, acid etching, oxidation, etc. These methods of surface creations lead to the generation defects in the crystal structure, which negatively affects the physico-mechanical and biological properties of the dental implant. Coatings made by classical technologies have negative properties: increased propensity to microcracks, low fatigue strength, insufficient wear resistance, hydrophobic properties, low dielectric parameters. The purpose of our work is to create a new technological process and a new coating with the elimination of these factors. We have developed a new glass-ceramic nanocoating Pateks based on silicon (SiOCN system), which is made by deposition of vapors of organic and minerals compounds of silicon, carbon, nitrogen at the atmospheric pressure by the PACVD method with activation by cold atmospheric plasma. The developed technology combines the process of coating and plasma sterilization at atmospheric pressure without the use of vacuum chambers and specialized baths using small-sized and low-power equipment, which can be used in clinical settings before the installation of dental implants and suprastructures

Piranha-etched titanium nanostructure reduces biofilm formation in vitro

ObjectivesNano-modified surfaces for dental implants may improve gingival fibroblast adhesion and antibacterial characteristics through cell-surface interactions. The present study investigated how a nanocavity titanium surface impacts the viability and adhesion of human gingival fibroblasts (HGF-1) and compared its response to Porphyromonas gingivalis with those of marketed implant surfaces.Material and methodsCommercial titanium and zirconia disks, namely, sandblasted and acid-etched titanium (SLA), sandblasted and acid-etched zirconia (ZLA), polished titanium (PT) and polished zirconia (ZrP), and nanostructured disks (NTDs) were tested. Polished titanium disks were etched with a 1:1 combination of 98% H2SO4 and 30% H2O2 (piranha etching) for 5 h at room temperature to produce the NTDs. Atomic force microscopy was used to measure the surface topography, roughness, adhesion force, and work of adhesion. MTT assays and immunofluorescence staining were used to examine cell viability and adhesion after incubation of HGF-1 cells on the disk surfaces. After incubation with P. gingivalis, conventional culture, live/dead staining, and SEM were used to determine the antibacterial properties of NTD, SLA, ZLA, PT, and ZrP.ResultsEtching created nanocavities with 10–20-nm edge-to-edge diameters. Chemical etching increased the average surface roughness and decreased the surface adherence, while polishing and flattening of ZrP increased adhesion. However, only the NTDs inhibited biofilm formation and bacterial adherence. The NTDs showed antibacterial effects and P. gingivalis vitality reductions. The HGF-1 cells demonstrated greater viability on the NTDs compared to the controls.ConclusionNanocavities with 10–20-nm edge-to-edge diameters on titanium disks hindered P. gingivalis adhesion and supported the adhesion of gingival fibroblasts when compared to the surfaces of currently marketed titanium or zirconia dental implants.Clinical relevanceThis study prepared an effective antibacterial nanoporous surface, assessed its effects against oral pathogens, and demonstrated that surface characteristics on a nanoscale level influenced oral pathogens and gingival fibroblasts.Clinical trial registration: not applicable

Effects of the internal contact surfaces of dental implants on screw loosening: A 3-dimensional finite element analysis

Statement of problemThe effects of the internal contact surfaces of dental implants on screw loosening have yet to be investigated. PurposeThe purpose of this 3-dimensional finite element analysis (FEA) study was to evaluate and compare the mechanical effects of the abutment implant angle (θ), the abutment screw head diameter (D), and the abutment screw length (L) on screw loosening. Material and methodsA total of 27 models presenting various mechanical scenarios were built by using combinations of 3 different θ (30 degrees, 45 degrees, and 60 degrees), D (2.65 mm, 2.75 mm, and 2.85 mm), and L (4 mm, 5 mm, and 6 mm). In FEA, a static test with a 200-N force inclined 30 degrees in the implant axial direction was applied to the upper surface of the abutment to evaluate and compare the maximum von Mises stresses of the implant components and the maximum total deformation in all models. In addition, modal analysis was applied to identify the natural frequencies in all models under free (unforced) vibration, and a Kruskal-Wallis statistical test (α=.05) was performed, followed by multiple pairwise comparisons by using the Dunn test. ResultsThe Kruskal-Wallis test found a significant influence of the θ on implant stress, total deformation, and natural frequency (P<.001). For example, increasing the θ from 30 degrees to 45 degrees and 60 degrees can considerably reduce the model’s natural frequencies to 18% and 26%, respectively. Similarly, the test underscored the significant impact of the D on both abutment screw stress and abutment stress (P=.010 and P=.002, respectively). However, the L appeared to have no significant effect on any of the dependent variables (P>.05). ConclusionsThe θ and the D significantly influenced the stresses of dental implant components, total deformation, and natural frequency of the model, which may impact the mechanical stability of the screw joint. However, the L does not appear to affect these values significantly.

A Comparative Investigation of Chemical Decontamination Methods for In-Situ Cleaning of Dental Implant Surfaces.

Surface chemistry evaluation is crucial in assessing the efficacy of chemical decontamination products for titanium implants. This study aimed to investigate the effectiveness of chemical decontamination solutions in cleaning a contaminated dental implant surface and to evaluate the potential of combining Pluronic gel with hydrogen peroxide (NuBone®Clean) by evaluating pellicle disruption and re-formation on implant surfaces. In addition, ensuring safety with in vitro and human testing protocols. X-ray Photoelectron Spectroscopy (XPS) was utilised for surface analysis. All the tested gels had some effect on the surface cleanness except for PrefGel®. Among the tested chemical decontamination candidates, NuBone®Clean demonstrated effectiveness in providing a cleaner titanium surface. Furthermore, none of the tested chemical agents exhibited cytotoxic effects, and the safety assessment showed no adverse events. The results of this study highlight the significance of conducting comprehensive evaluations, encompassing safety and efficacy, before introducing new chemical agents for dental treatments. The findings suggest that NuBone®Clean shows potential as a chemical decontamination solution for implant surfaces. However, further investigation through randomised clinical trials is necessary. By adhering to rigorous testing protocols, the development of safe and efficient chemical decontamination strategies can be advanced, benefiting patients and promoting progress in implant dentistry.

Virucidal Efficacy of Gaseous Ozone Against Type 1 Herpes Simplex Virus (HSV-1)

ABSTRACT Viruses represent a major threat to human health and are capable of spreading either via direct exposure or contamination of inanimate surfaces. Certain viruses have been shown to remain viable on surfaces of dental implants and devices, fabrics and on plastics for hours, days and weeks representing a source of continuous viral transmission which must be mitigated. In this study, we compared the effect of varying concentrations of gaseous ozone (40, 20, 10, 5, and 1 ppm) on Herpes Simplex Virus (HSV-1) coated on the surfaces of clear polystyrene tissue culture (TC) plates and stainless-steel disc at varying time intervals (1.5, 3, 6, and 8 h) at >90% relative humidity and at 21–25 ˙C (±2˙C). Test samples were placed at a height of 1 and 1.5 m from ozone source. Viral viability after ozone exposure was determined using Vero cells and the viral titer was quantified using the Spearman–Karber’s method. Overall, inactivation of HSV-1 was dependent on ozone concentration and the duration of exposure. At 20 and 40 ppm, ozone rapidly depleted virus viability after 6 h. At 5 and 10 ppm a time-dependent reduction in viral infectivity was observed. At 10 ppm, viral titer decreased from approximately 5.2 pfu/mL at T = 0 to 3.5 and 2.1 pfu/mL after 1.5- and 6-h exposure on plastic surfaces. Similarly, viral titer decreased from approximately 5.6 pfu/mL at T = 0 to 3.0 to 2.0 pfu/mL at same time frame on steel surfaces. This study builds on earlier research in the field and demonstrates the ability of gaseous ozone to inactivate HSV-1 on two surfaces commonly found in food, medical and dental settings. This study recommends that further work is completed to identify optimum ozone, humidity, and temperature combinations to inactivate such viruses on surfaces found within these environments.

Photofunctionalization of Dental Implant Surfaces - A Histomorphometric Animal Study.

To compare and evaluate the degree of osseointegration of UV-treated (photo functionalized) and non-treated dental implants surface coated with Calcium phosphate using the Resorbable Blast Media (RBM) technique in an animal model. Evaluative-Animal study design. Six titanium dental implants of diameter 3.2 mm and length of 8 mm with Calcium phosphate coated surface using RBM or resorbable blast media technology (Implant Genesis: Genesis Normo Implant system) were placed epicrestally into the proximal femoral condyle of New Zealand white female rabbits such that each animal received two implants. Before implantation, one out of the two dental implants was photo functionalized with intense UV light for 15 minutes. After twelve weeks of healing, the animals were euthanized and the harvested specimens were analyzed using histomorphometric light microscopy to assess two parameters bone-implant contact and bone volume density. SPSS version 23. P less than 0.05 is considered statistically significant. Tests used ANOVA followed by Tukey post hoc test. All six dental implants were osseointegrated. The overall mean bone-implant contact area (BIC) was 57.76% for non-UV treated whereas 88.4367% for UV-treated dental implants. The overall mean bone volume density (BVD) was 32.2333% for non-UV treated whereas 67.7533% for UV-treated dental implants. Significant effects were observed on the osseointegration of dental titanium implants within twelve weeks after UV photo functionalization. The UV photo functionalization of dental titanium implants in the current study significantly altered the BIC and bone density on osseointegration when observed over twelve weeks.

On the Biotribological Surfaces of Dental Implants: Investigation in the Framework of Osseointegration

In the last decades, the use of dental implants has been growing exponentially, but some clinical issues such as inflammations, infections or mechanical complications like fractures or implant loosening, are still open, leading to a failure and implants' revision surgery. Many researchers state that one of the main reasons is certainly due to a not complete or stable implant osseointegration respect the surrounding bone. As stated in literature the formation and the growth of the bone in contact with the implant is strictly correlated with the micro topography of the implant contact surfaces, because of the biotribological, biological and chemical interactions occurring on the surface. To date, however, only arithmetical roughness is reported in the most part of investigations as a valid surfaces' topographical parameter which could be correlated with osseointegration. Moreover, a consolidated and standardized procedure for dental implant surface measurements is not established. Hence, the aim of this investigation was to propose an advanced methodology for analyzing dental implant surfaces based on optical measurements and accurate data processing, and to discuss the results obtained on a real implant, in the framework of osseointegration and biotribological contact literature findings. With reference to a commercial dental implant, the topography was accurately achieved by an optical confocal and interferometric apparatus and then post processed to obtain all the quantities necessary for the contact surface accurate description discussing the role of the topographical quantities on the influence of bone/implant contact/osseointegration phenomena. Height, spatial, hybrid and functional parameters were presented for both waviness and roughness profiles providing significant discrepancies in most of the roughness values. On the other hand, the additional specific investigations such as surface isotropy or particle analysis may yield the basis for a novel protocol of surfaces topographical characterization procedure in dentistry.

Comparative analysis of the area of the external surface of dental implants

Comparative analysis of the area of the external surface of dental implants

Emission and Migration of Nanoscale Particles during Osseointegration and Disintegration of Dental Implants in the Clinic and Experiment and the Influence on Cytokine Production.

The emission of nanoscale particles from the surfaces of dental implants leads to the cumulative effect of particle complexes in the bone bed and surrounding soft tissues. Aspects of particle migration with the possibility of their involvement in the development of pathological processes of systemic nature remain unexplored. The aim of this work was to study protein production during the interaction of immunocompetent cells with nanoscale metal particles obtained from the surfaces of dental implants in the supernatants. The ability to migrate nanoscale metal particles with possible involvement in the formation of pathological structures, in particular in the formation of gallstones, was also investigated. The following methods were used: microbiological studies, X-ray microtomography, X-ray fluorescence analysis, flow cytometry, electron microscopy, dynamic light scattering, and multiplex immunofluorescence analysis. For the first time, titanium nanoparticles in gallstones were identified by X-ray fluorescence analysis and electron microscopy with elemental mapping. The multiplex analysis method revealed that the physiological response of the immune system cells, in particular neutrophils, to nanosized metal particles significantly reduced TNF-a production both through direct interaction and through double lipopolysaccharide-induced signaling. For the first time, a significant decrease in TNF-a production was demonstrated when supernatants containing nanoscale metal particles were co-cultured with proinflammatory peritoneal exudate obtained from the peritoneum of the C57Bl/6J inbred mice line for one day.

Keratinocyte Proliferation and Hemidesmosome Formation on Surfaces for Dental Implants: In Vitro Study.

To demonstrate the likelihood of the polyetheretherketone (PEEK), zirconia (ZrO2), and titanium (Ti) disks to support proliferation and hemidesmosome formation of gingival cells. Water contact angle was performed on each material, and surface roughness (Ra) was measured. Scanning electron microscopy and x-ray photoelectron spectroscopy were used. Later, oral keratinocyte cells were cultured on disks, and metabolic activity and expression of hemidesmosome markers, integrin α6 and β4, in relation to the biomaterial disks at 1, 3, and 5 days of cell culture were quantified. Tissue culture polystyrene was used as the control. Statistical analysis was performed with analysis of variance (ANOVA) with Tukey post hoc comparison test. A P value of < .05 was considered statistically significant. The water contact angle ranged from 70.2 degrees (Ti) to a maximum of hydrophobicity of 93.3 degrees (PEEK). Ra was highest on ZrO2, followed by PEEK. Ti showed the most keratinocyte metabolic activity at 1, 3, and 5 culture periods. Contrarily, ZrO2 and PEEK disks had lower keratinocyte metabolic activity at all observation times, with no statistical differences between both groups. Integrin α6 and β4 expression was highest on TCPS and ZrO2 compared to Ti and PEEK. Keratinocytes proliferated faster on Ti than on ZrO2 and PEEK substrates, and expression of hemidesmosome formation markers, integrin α6 and β4, were higher on ZrO2 than either Ti or PEEK. Int J Oral Maxillofac Implants 2023;38:496-502. doi: 10.11607/jomi.9894.

Ozonated Water Promotes in vitro Decontamination of Dental Implants Surface

ABSTRACT Although studies have shown high survival rates of dental implants, complications may occur mainly due to peri-implant infections. These highlight the importance of establishing protocols for implant decontamination using adjuvant therapies, such as ozone. This study aimed to evaluate the potential for in vitro decontamination of ozonated water on implants surface. Sixteen titanium implants were used, distributed into the groups (n = 4): group E – sterile implants; group C – contaminated implants; group O40 – contaminated implants treated with ozonated water 40 mg/L; and group O60 – contaminated implants treated with ozonated water 60 mg/L. The implants of groups C, O40, and O60 were contaminated in vitro with biofilm. Groups O40 and O60 were decontaminated with ozonated water for 1 minute. Microbiologic analysis was performed by counting colony-forming units (CFUs). Experimental group comparisons were done using a one-way ANOVA test with Tukey’s posttest; a comparison between groups O40 and O60 was done using an independent t-test (p < 0.05). There was a difference among all experimental groups (p = 0.000), with a more significant reduction in CFUs in group O60 (0.83 × 107 ± 0.06) compared to group C (3.41 × 107 ± 0.41). It was concluded that ozonated water 60 mg/L has shown good potential for in vitro decontamination of implants surface.

Evaluation of the Photoactivation Effect of 3% Hydrogen Peroxide in the Disinfection of Dental Implants: In Vitro Study

Photoactivation of 3% hydrogen peroxide with a 445 nm diode laser represents a relatively new, insufficiently researched antimicrobial method in the treatment of peri-implantitis. The purpose of this work is to evaluate the effect of photoactivation of 3% hydrogen peroxide with a 445 nm diode laser, and to compare the obtained results with 0.2% chlorhexidine treatment and 3% hydrogen peroxide treatment without photoactivation, in vitro, on the surface of dental implants contaminated with S. aureus and C. albicans biofilms. Previously, 80 infected titanium implants with S. aureus and C. albicans cultures were divided into four groups: G1-negative control (no treatment), G2-positive control (0.2% chlorhexidine), G3 (3% hydrogen peroxide), and G4 (photoactivated 3% hydrogen peroxide). The number of viable microbes in each sample was determined by the colony forming unit (CFU) count. The results were statistically processed and analyzed, showing a statistically significant difference across all groups compared to the negative control (G1), and the absence of a statistically significant difference between groups G1-G3. The new antimicrobial treatment, according to the results, could be worthy of further analysis and research.

Implant abutment using hand drivers versus torque wrench.

The most frequent instrument used to begin tightening screws is a manually regulated screwdriver. Regarding manually regulated screwdrivers, predicted margins of error vary between fifteen percent to forty eight percent. Mechanical Torque restricting devices can consistently produce the requisite torques. As a result, devices like wrenches are needed to achieve the desirable values of torque. Hence, the present study was designed to evaluate the torque difference between handheld drivers and torque wrench and thereby its effect on the internal threads of implant surface.120 blocks was prepared from an autopolymerizing type of acrylic material each with a dimension of 1 inch. The centre of each block was affixed with analogue of dental impalnts with dimensions of 3.5 mm width and 13 mm length. With 60 specimens each, these models were split into two categories: hand torque specimens category and torque wrench specimens category. A stereomicroscope was used to look at the implant analog's internal threading architecture at a magnification of 100. At the bottom and top, four threads were spaced apart by a certain amount. Biowizard software was used for the assessment, and the results were recorded. Threads on the internal surface of dental implants were produced once more following torquing the implant's impression, and the stereomicroscope was used to quantify the separation between the 4 threads. Statistics were used to correlate the readings. All study participants' hand torque as well as torque wrench measurements were documented and statistical analysis was performed on them. When there was statistical analysis of the measurements then it was observed that mean values of torque in specimens included category of manual torque application was found out to be 33.6 ± 6.510 Ncm. On the other hand the mean values of torque in specimens included in category of torque application by torque wrench were found out to be 33.57 ± 3.472 Ncm. The outcome showed operator heterogeneity for both categories and operator variance when using a manual driver to generate torque. One independent - sample t test was used to contrast the mean data between the two categories, and P< 0.05 was chosen to determine whether the intergroup difference was meaningful. Because the torque values obtained with hand tightening were uneven, it may be concluded that different levels of hand torquing skill caused the torque to fluctuate. The torque wrench device displayed the desired torque data in the range that the manufacturer had advised. However, utilising manual drivers and a mechanical torque instrument did not cause any modifications to thread on the internal surface, and it rarely underwent significant deformation during the preliminary tightening torque readings. Thus, given that manually hand regulated drivers create a range of torques, it may be inferred that the employment of mechanical torque restricting instruments should be required.

Excellent Mechanical Properties, Wettability and Biological Response of Ultrafine-Grained Pure Ti Dental Implant Surface Modified by SLActive

Excellent Mechanical Properties, Wettability and Biological Response of Ultrafine-Grained Pure Ti Dental Implant Surface Modified by SLActive

Dental Implant Surface Decontamination and Surface Change of an Electrolytic Method versus Mechanical Approaches: A Pilot In Vitro Study

Dental implants are the preferred fixed oral rehabilitation for replacing lost teeth. When peri-implant tissues become inflamed, the removal of plaque accumulating around the implant becomes imperative. Recently, several new strategies have been developed for this purpose, with electrolytic decontamination showing increased potential compared to traditional mechanical strategies. In this in vitro pilot study, we compare the efficacy of an electrolytic decontaminant (Galvosurge®) with an erythritol jet system (PerioFlow®) and two titanium brushes (R-Brush™ and i-Brush™) in removing Pseudomonas aeruginosa PAO1 biofilms from implants. Changes in the implant surface after each approach were also evaluated. Twenty titanium SLA implants were inoculated with P. aeruginosa and then randomly assigned to each treatment group. After treatment, decontamination efficacy was assessed by quantifying colony-forming units (log10 CFU/cm2) from each implant surface. Scanning electron microscopy was used to analyse changes in the implant surface. With the exception of R-Brush, all treatment strategies were similarly effective in removing P. aeruginosa from implants. Major surface changes were observed only in implants treated with titanium brushes. In conclusion, this pilot study suggests that electrolytic decontamination, erythritol-chlorhexidine particle jet system and i-Brush™ brushing have similar performance in removing P. aeruginosa biofilm from dental implants. Further studies are needed to evaluate the removal of more complex biofilms. Titanium brushes caused significant changes to the implant surface, the effects of which need to be evaluated.

Microbiological profile of peri-implantitis: Analyses of microbiome within dental implants.

To characterize the microbiome composition within dental implants of peri-implantitis subjects and healthy controls using 16S rRNA gene sequencing. Twenty-three subjects with healthy (n=11 implants) and diseased (peri-implantitis, n=21) implants were included in this controlled clinical cross-sectional study. Samples were obtained from internal surfaces of dental implants using sterile paper points for microbiological analysis. DNA was extracted, and the16S rRNA gene was amplified using universal primers targeting the V3-V4 regions. The resulting 16S polymerize chain reaction amplicons were sequenced on Illumina MiSeq, and the sequences were processed using DADA2 and the Human Oral Microbiome Database (HOMD) as references. Alpha and Beta diversity, as well as core microbiome and differential abundance analyses were then performed using the MicrobiomeAnalyst workflow. A significant increase in microbial diversity was observed in the internal implant surface of healthy implants compared with the internal surfaces of peri-implantitis (Shannon p=0.02). Bacterial community structure was significantly different among groups (p=0.012). High levels of Gram-positive bacteria were detected inside implants with peri-implantitis compared to healthy implants, especially Enterococci. There is a shift in bacterial diversity inside implants with peri-implantitis from the healthy control. The microbial colonization within that space might contribute to the etiology of peri-implant disease.

Assessment of Inhibition of Biofilm Formation on Non-Thermal Plasma-Treated TiO2 Nanotubes.

Peri-implantitis is an inflammatory disease similar to periodontitis, caused by biofilms formed on the surface of dental implants. This inflammation can spread to bone tissues and result in bone loss. Therefore, it is essential to inhibit the formation of biofilms on the surface of dental implants. Thus, this study examined the inhibition of biofilm formation by treating TiO2 nanotubes with heat and plasma. Commercially pure titanium specimens were anodized to form TiO2 nanotubes. Heat treatment was performed at 400 and 600 °C, and atmospheric pressure plasma was applied using a plasma generator (PGS-200, Expantech, Suwon, Republic of Korea). Contact angles, surface roughness, surface structure, crystal structure, and chemical compositions were measured to analyze the surface properties of the specimens. The inhibition of biofilm formation was assessed using two methods. The results of this study showed that the heat treatment of TiO2 nanotubes at 400 °C inhibited the adhesion of Streptococcus mutans (S. mutans), associated with initial biofilm formation, and that heat treatment of TiO2 nanotubes at 600 °C inhibited the adhesion of Porphyromonas gingivalis (P. gingivalis), which causes peri-implantitis. Applying plasma to the TiO2 nanotubes heat-treated at 600 °C inhibited the adhesion of S. mutans and P. gingivalis.