Comparative biology of chronic and aggressive periodontitis vs. peri-implantitis

The clinical efficacy of powder air-polishing in the non-surgical treatment of peri-implant diseases: A systematic review and meta-analysis

Peri-implant diseases, characterized by inflammatory conditions affecting peri-implant tissues, encompass peri-implant mucositis and peri-implantitis. Peri-implant mucositis is an inflammatory lesion limited to the mucosa around an implant, while peri-implantitis extends from the mucosa to the supporting bone, causing a loss of osseointegration. For non-surgical treatments, we tested the null hypothesis that the presence or absence of air-polishing made no difference. The study focused on randomized controlled trials (RCTs) comparing air-polishing with mechanical or ultrasonic debridement, evaluating outcomes such as bleeding on probing (BOP), probing depth (PD), plaque index/plaque score (PI/PS), clinical attachment level (CAL), bone loss, and mucosal recession (MR). Two independent reviewers conducted data extraction and quality assessments, considering short-term (<6 months) and long-term (≥6 months) follow-up periods. After screening, ten articles were included in the meta-analysis. In nonsurgical peri-implant disease management, air-polishing moderately mitigated short-term PI/PS for peri-implant mucositis and showed a similar improvement in long-term BOP and bone loss for peri-implantitis compared to the control group. The Egger test found no evidence of publication bias except for the long-term PI/PS of peri-implant mucositis. Leave-one-out analysis confirmed the stability of the results. The findings highlight the need for future research with longer-term follow-up and high-quality, multi-center, large-sample RCTs.

In vitro evaluation of surface roughness of titanium abutments after air polishing with different abrasive powders

OBJECTIVES

The purpose of this study was to evaluate the effects of air polishing with sodium bicarbonate and erythritol powders on surface roughness and morphological changes in titanium abutments.

METHODS

A total of 45 grade V titanium discs were divided in three groups: Group A (Control) air polished with air/water; Group B, air polished with sodium bicarbonate powder; and Group C, air polished with erythritol powder. After air polishing, the samples' roughness (Sa) in micrometres were analysed with an optical profilometer. The samples' surface morphology study was conducted via scanning electronic microscope (SEM). Data were described using mean and standard deviation of roughness values (Sa). Inferential analysis was performed using the ANOVA multiple comparison test followed by Tukey's post hoc test. Both tests used a 5% level of significance.

RESULTS

After air polishing, average roughness of group A, B and C were 0.036, 0.046 and 0.037 μm, respectively, with statistically significant differences between groups A and B (p < 0.05). No statistically significant differences were found between group A and group C, as well as between group B and C (p > 0.05). As for the morphology analysis, damages to the titanium surface were only observed in group B.

CONCLUSIONS

The study indicates that air polishing with erythritol powder maintains titanium abutment integrity better than sodium bicarbonate, which increased surface roughness and caused damage. Erythritol is preferable for minimizing surface alterations and maintaining morphological stability.

Comparative Study of Callistemon citrinus (Bottlebrush) and Punica granatum (Pomegranate) Extracts for Sustainable Synthesis of Silver Nanoparticles and Their Oral Antimicrobial Efficacy

A comparative study was applied to investigate the potential of Callistemon citrinus (bottlebrush) flower extract (BBE) and Punica granatum (pomegranate) peel extracts (PPE) for the sustainable synthesis of the silver nanoparticles, Ag-BBE and Ag-PPE, respectively. The synthesis process of Ag NPs using the selected extracts was applied under optimized conditions. Hence, the effect of the selected plant's type on the different characteristics of the synthesized green Ag NPs was investigated. The UV-Vis spectroscopy revealed the presence of the characteristic silver peaks at 419 and 433 nm of the Ag-BBE and Ag-PPE, respectively. The XRD spectra reported the fcc phase formation of Ag NPs. The TEM results highlighted the morphological features of the synthesized Ag NPs. with a size range of 20-70 nm, and with 10-30 nm for Ag-BBE and Ag-PPE, correspondingly. The Raman spectra revealed characteristic silver bands in the Ag-PPE and reflected some bands related to the natural extract in the Ag-BBE sample. The antimicrobial activity and statistical analysis investigation were conducted against four selected oral pathogens (Staphylococcus aureus (SA), Candida albicans (CA), Staphylococcus epidermidis (S. epi), and Enterococcus faecalis (EF)). Both tested extracts, BBE, and PPE, revealed potential effectivity as reducing and capping agents for Ag NP green synthesis. However, the synthesized NPs demonstrated different features, depending on the used extract, reflecting the influence of the plant's biomolecules on the nanoparticles' properties.

A Biomimetic Multifunctional Scaffold for Infectious Vertical Bone Augmentation

The regenerative treatment of infectious vertical bone defects remains difficult and challenging today. Current clinical treatments are limited in their ability to control bacteria and infection, which is unfavorable for new bone formation and calls for a new type of material with excellent osteogenic and antibacterial properties. Here a multifunctional scaffold is synthesized that mimics natural bone nanostructures by incorporating silver nanowires into a hierarchical, intrafibrillar mineralized collagen matrix (IMC/AgNWs), to achieve the therapeutic goals of inhibiting bacterial activity and promoting infectious alveolar bone augmentation in rats and beagle dogs. An appropriate concentration of 0.5 mg mL-1 AgNWs is selected to balance biocompatibility and antibacterial properties. The achieved IMC/AgNWs exhibit a broad spectrum of antimicrobial properties against Gram-negative Porphyromonas gingivalis and Gram-positive Streptococcus mutans. When the IMC/AgNWs are cocultured with periodontal ligament stem cells, it possesses excellent osteoinductive activities under both non-inflammatory and inflammatory conditions. By constructing a rat mandibular infected periodontal defect model, the IMC/AgNWs achieve a near-complete healing through the canonical BMP/Smad signaling. Moreover, the IMC/AgNWs enhance vertical bone height and osseointegration in peri-implantitis in beagle dogs, indicating the clinical translational potential of IMC/AgNWs for infectious vertical bone augmentation.

Bioinformatics investigation of adaptive immune-related genes in peri-implantitis and periodontitis: Characteristics and diagnostic values

BACKGROUND

Peri-implantitis and periodontitis have similar immunological bioprocesses and inflammatory phenotypes. In the inflammatory process, the adaptive immune cells can drive the development of disease. This research investigated the differences and diagnostic significance of peri-implantitis and periodontitis in adaptive immune responses.

METHODS

We acquired four GEO datasets of gene expressions in surrounding tissues in healthy person, healthy implant, periodontitis, and peri-implantitis patients. The structural characteristics and enrichment analyses of differential expression genes were examined. The adaptive immune landscapes in peri-implantitis and periodontitis were then evaluated using single sample gene set enrichment analysis. The STRING database and Cytoscape were used to identify adaptive hub genes, and the ROC curve was used to verify them. Finally, qRT-PCR method was used to verify the expression level of Hub gene in activated T cells on the titanium-containing or titanium-free culture plates.

RESULTS

At the transcriptome level, the data of healthy implant, peri-implantitis and periodontitis were highly dissimilar. The peri-implantitis and periodontitis both exhibited adaptive immune response. Except for the activated CD4+T cells, there was no significant difference in other adaptive immune cells between peri-implantitis and periodontitis. In addition, correlation analysis showed that CD53, CYBB, and PLEK were significantly positively linked with activated CD4+T cells in the immune microenvironment of peri-implantitis, making them effective biomarkers to differentiate it from periodontitis.

CONCLUSIONS

Peri-implantitis has a uniquely immunogenomic landscape that differs from periodontitis. This study provides new insights and ideas into the activated CD4+T cells and hub genes that underpin the immunological bioprocess of peri-implantitis.

Peri-implant mucositis and peri-implantitis: key features and differences

Peri-implant diseases are frequent complications that occur around osseointegrated endosseous implants and are the result of an imbalance between the bacterial challenge and host response. Peri-implant diseases may affect the peri-implant mucosa only (peri-implant mucositis) or also involve the supporting bone (peri-implantitis). Early detection of peri-implant diseases and timely treatment is important for the success of dental implant treatment. Peri-implant probing is essential to assess the peri-implant health status and should be done at each recall visit. Dental practitioners should be familiar with the clinical and radiological features of both conditions in order to make an accurate diagnosis and determine the appropriate treatment required. This article aims to provide clinicians with an understanding of the key differences between peri-implant health, peri-implant mucositis and peri-implantitis.

Evaluation of salivary stress markers and inflammatory cytokine levels in peri-implantitis patients

BACKGROUND AND OBJECTIVE

Psychological stress has been identified in some observational studies as a potential factor that may modify and affect periodontal diseases, but there are no similar data for peri-implantitis. The aim of this study was to determine the relationship between interleukin (IL)-1β, IL-6, IL-10, interferon (IFN)α inflammatory cytokines and the psychological stress-related markers, glucocorticoid receptor-α (GRα), and salivary α-amylase (sAA) gene expression levels in saliva samples obtained from healthy implants and peri-implantitis patients.

MATERIALS AND METHODS

The study included a total of 50 systemically healthy subjects. Peri-implant clinical parameters were recorded and psychological stress level was evaluated with the hospital anxiety and depression scale (HAD) and state-trait anxiety inventory (STAI) questionnaire forms. Following the evaluations, the patients were divided into 4 groups according their stress and clinical status (Ia, Ib, IIa, IIb). IL-1β, IL-6, IL-10, IFNα, GRα, sAA gene expression levels in the saliva samples were quantified by quantitative polymerase chain reaction (qPCR).

RESULTS

In the group of peri-implantitis who had a high score in stress level assessment scales, significantly higher IL-1β, IL-6, sAA expression levels were observed (p < 0.001). The IL-10 gene expression levels were lower in the groups with a high score in the stress level assessment scales (p < 0.001). GRα gene was expressed at lower levels in the group of peri-implantitis who had a high score in stress level assessment scales but the difference was not statistically significant (p = 0.065).

CONCLUSION

The study findings suggest that psychological stress may increase the inflammation associated with peri-implantitis by affecting cytokine expression levels.

CLINICAL RELEVANCE

To prevent peri-implantitis or reduce its prevalence, it could be beneficial to evaluate stress levels and identify individuals experiencing stress.

Quantity and Size of Titanium Particles Released from Different Mechanical Decontamination Procedures on Titanium Discs: An In Vitro Study

Complications such as peri-implantitis could ultimately affect the survival of a dental implant. The prevention and treatment of peri-implant diseases require managing bacterial biofilm and controlling environmental risks, including the presence of pro-inflammatory titanium (Ti) particles in the peri-implant niche. Objectives included the evaluation of the size and quantity of Ti particles released from moderately roughened Ti surfaces during common mechanical surface decontamination methods. One hundred and forty moderately roughened Ti discs were divided into seven groups (n = 20 per group); six groups received mechanical decontamination procedures (ultrasonic scaling (US) with a metal tip and poly-ether-ketone (PEEK) under low and medium power settings, air-polishing with erythritol powder, and Ti brush), and the control group underwent air-water spray using a dental triplex. The rinsing solution was collected for Ti mass analysis using inductively coupled plasma mass spectrometry (ICPMS), as well as for Ti particle size and count analysis under scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS). US metal tip instrumentation generated 34.00 ± 12.54 μg and 34.44 ± 6.08 μg of Ti under low and medium power settings, respectively. This amount of Ti generation was significantly higher than other instrumentation methods. The mean Ti particle size of the US groups ranged from 0.89 ± 0.27 μm to 1.25 ± 0.24 μm. No statistically significant difference was found in the particle size among US groups and Ti brush group (1.05 ± 0.11 μm), except for US with the PEEK tip, where a significantly smaller mean particle diameter was found at the low power setting (0.89 ± 0.27 μm). Mechanical instrumentation can produce Ti particulates and modify the implant surfaces. US using a metal tip generated the highest amount of Ti with smaller Ti size particles compared to all other commonly used mechanical surface instrumentations. The EDS analysis confirmed Ti in PEEK US tips. It can be suggested that deterioration from the PEEK US tip and Ti brush, as observed under SEM, is an additional source of Ti release during Ti surface decontamination.

Effect of preoperative chlorhexidine, essential oil, and cetylpyridinium chloride mouthwashes on bacterial contamination during dental implant surgery: A randomized controlled clinical trial

Background

Although the role of chlorhexidine and other mouthwashes in periodontal therapy has been elucidated, little information is available on their use as routine preoperative mouth rinses before surgery, especially in periodontal procedures such as dental implant surgery.

Objective

This study aimed to compare the efficacy of preoperative chlorhexidine, essential oil, and cetylpyridinium chloride mouthwashes in reducing bacterial contamination at the time of implant placement.

Materials and Methods

Eligible patients who underwent dental implant surgery were randomly divided into four groups based on the mouthwash used: (1) 0.12 % chlorhexidine, (2) essential oil, (3) cetylpyridinium chloride, and (4) saline (served as the control group). All the patients of each group rinsed preoperatively with 15 mL of the respective mouthwash for 60 s. Saliva samples before (pre) and immediately after rinsing with the mouthwash (post) and after suturing the flap (end) were collected on the day of the implant placement. Real-time quantitative polymerase chain reaction (qPCR) was performed to analyze the samples and quantify the targeted periodontal pathogens using a propidium monoazide (PMA) dye.

Results

Forty patients were included in the study. Real-time qPCR demonstrated a significant reduction in the number of pathogens in the saliva samples of the mouthwash groups compared to that of the control group. A statistically significant difference was observed between the groups for the pre-post and pre-end samples (p < 0.001) but not for the post-end samples (p = 0.203). A statistically significant difference was observed between the chlorhexidine, essential oil, and cetylpyridinium chloride mouthwash groups and the saline group (P < 0.001). The bacterial counts significantly differed with and without the use of the PMA dye.

Conclusions

Preoperative chlorhexidine, essential oil, and cetylpyridinium chloride mouthwashes can reduce the bacterial load at the time of implant placement, thereby reducing the incidence of implant-related complications.

New insights on collagen structural organization and spatial distribution around dental implants: a comparison between machined and laser-treated surfaces

BACKGROUND

One of the main factors for the osseointegration of dental implants is the development of an adequate soft tissue barrier, mainly composed by collagen, which protects the implant from bacterial development. The structural features of the peri-implant collagen are influenced by the implant components and, in particular, by the type of the surface. In the clinical practice, healing abutments are characterized by smooth surfaces, named machined. Recently, a new laser technique, Synthegra, has been developed to obtain a topography-controlled surface with micrometric regular pores that seems reducing the risk of peri-implantitis. Based on this background, this study aims investigating the structural organization and spatial distribution of collagen surrounding healing abutments characterized by laser-treated and machined surfaces.

METHODS

Gingiva portions surrounding custom-made healing abutments (HA), characterized by alternated laser-treated and machined surfaces, were collected and analyzed by combining Fourier Transform InfraRed Imaging (FTIRI) spectroscopy, a non-invasive and high-resolution bidimensional analytical technique, with histological and multivariate analyses.

RESULTS

Masson's trichrome staining, specific for collagen, highlighted a massive presence of collagen in all the analyzed samples, evidencing a surface-related spatial distribution. The nature of collagen, investigated by the FTIRI spectroscopy, appeared more abundant close to the laser-treated surface, with a perpendicular disposition of the bundles respect to the HA; conversely, a parallel distribution was observed around the machined surface. A different secondary structure was also found, with a higher amount of triple helices and a lower quantity of random coils in collagen close to the laser treated surfaces.

CONCLUSIONS

FTIRI spectroscopy demonstrates that the use of a laser treated transmucosal surface can improve the morphological organization of the peri-implant collagen, which presents a distribution more similar to that of natural teeth.

TRIAL REGISTRATION

This trial is registered with ClinicalTrials.gov Identifier: (Registration Number: NCT05754970). Registered 06/03/2023, retrospectively registered, https://clinicaltrials.gov/show/NCT05754970 .

Reprogramming mitochondrial metabolism of macrophages by miRNA-released microporous coatings to prevent peri-implantitis

Although various new biomaterials have enriched the methods for peri-implant inflammation treatment, their efficacy is still debated, and secondary operations on the implant area have also caused pain for patients. Recently, strategies that regulate macrophage polarization to prevent or even treat peri-implantitis have attracted increasing attention. Here, we prepared a laser-drilled and covered with metal organic framework-miR-27a agomir nanomembrane (L-MOF-agomir) implant, which could load and sustain the release of miR-27a agomir. In vitro, the L-MOF-agomir titanium plate promoted the repolarization of LPS-stimulated macrophages from M1 to M2, and the macrophage culture supernatant promoted BMSCs osteogenesis. In a ligation-induced rat peri-implantitis model, the L-MOF-agomir implants featured strong immunomodulatory activity of macrophage polarization and alleviated ligation-induced bone resorption. The mechanism of repolarization function may be that the L-MOF-agomir implants promote the macrophage mitochondrial function and metabolism reprogramming from glycolysis to oxidative phosphorylation. Our study demonstrates the feasibility of targeting cell metabolism to regulate macrophage immunity for peri-implantitis inhibition and provides a new perspective for the development of novel multifunctional implants.

A retrospective study of the long-term survival of RESTORE® dental implants with resorbable blast media surface

PURPOSE

The aim of this study was to retrospectively evaluate the survival and failure rates of RESTORE® implants over a follow-up period of 10-15 years at a university dental hospital and to investigate the factors affecting the survival rate of these dental implants.

METHODS

A total of 247 RESTORE® dental implants with a resorbable blast media (RBM) surface inserted in 86 patients between March 2006 and April 2011 at the Department of Periodontology of Seoul National University Dental Hospital were included. Patients with follow-up periods of less than 10 years were excluded, and data analysis was conducted based on dental records and radiographs.

RESULTS

Over a 10- to 15-year period, the cumulative survival rate of the implants was 92.5%. Seventeen implants (6.88%) were explanted due to implant fracture (n=10, 4.05%), peri-implantitis (n=6, 2.43%), and screw fracture (n=1, 0.4%). The results of univariate regression analysis using a Cox proportional hazards model demonstrated that implants placed in male patients (hazard ratio [HR], 4.542; 95% confidence interval [CI], 1.305-15.807; P=0.017) and implants that supported removable prostheses (HR, 15.498; 95% CI, 3.105-77.357; P=0.001) showed statistically significant associations with implant failure.

CONCLUSIONS

Within the limitations of this retrospective study, the RESTORE® dental implant with an RBM surface has a favorable survival rate with stable clinical outcomes.

Dental implant material related changes in molecular signatures in peri-implantitis - A systematic review of omics in-vivo studies

OBJECTIVE

Titanium particles have been shown in in-vitro studies to lead to the activation of specific pathways, this work aims to systematically review in- vivo studies examining peri-implant and periodontal tissues at the transcriptome, proteome, epigenome and genome level to reveal implant material-related processes favoring peri-implantitis development investigated in animal and human trials.

METHODS

Inquiring three literature databases (Medline, Embase, Cochrane) a systematic search based on a priori defined PICOs was conducted: '-omics' studies comparing molecular signatures in healthy and infected peri-implant sites and/or healthy and periodontitis-affected teeth in animals/humans. After risk of bias assessments, lists of differentially expressed genes and results of functional enrichment analyses were compiled whenever possible.

RESULTS

Out of 2187 screened articles 9 publications were deemed eligible. Both healthy and inflamed peri-implant tissues showed distinct gene expression patterns compared to healthy/diseased periodontal tissues in animal (n = 4) or human studies (n = 5), with immune response, bone metabolism and oxidative stress being affected the most. Due to the lack of available re-analyzable data and inconsistency in methodology of the eligible studies, integrative analyses on differential gene expression were not applicable CONCLUSION: The differences of transcriptomic signatures in between peri-implant lesions compared to periodontal tissue might be related to titanium particles arising from dental implants and are in line with the in-vitro data recently published by our group. Nevertheless, limitations emerge from small sample sizes of included studies and insufficient publication of re-analyzable data.

Effect of periostin in peri-implant sulcular fluid and gingival crevicular fluid: A comparative study

Background

Various similarities have been observed between gingival crevicular fluid (GCF) and peri-implant sulcular fluid (PISF). This has resulted in research that has evaluated similar biological fluid markers that are similar to those present within the gingival sulcus. These biomarkers have high sensitivity and are a reliable biological tool when compared to clinical and/or radiographic examination and aid in diagnosis as well as monitoring the progression of periodontal disease surrounding teeth as well as the implants.

Aim

The study aimed to compare the effectiveness of periostin in peri-implant sulcular and gingival crevicular fluids.

Materials and Methods

This experimental prospective in vitro analysis was done following clearance by the institutional ethical committee. A total of 100 patients were selected. They were categorized into two groups: (I) Group A patients had peri-implant disease (n = 50), whereas (II) Group B patients had periodontitis (n = 50). Clinical loss of attachment score was noted in six sites around natural teeth and four sites around the implants. Presterilized filter paper strips were inserted within the sulcus/pocket till pressure was felt for 60 s. Periostin concentration levels in GCF and PISF samples were measured by the enzyme-linked immunosorbent assay technique. Statistical analysis of data collected was performed using Shapiro-Wilk statistical tool for normally distributed numerical data.

. Results

Mean ± standard deviation concentration of periostin in gingival crevicular fluid from periodontitis cases was recorded as 20.15 ± 2.76 ng/30sn, whereas in PISF was 19.23 ± 1.89 ng/30sn. On statistical analysis, no statistically significant differences were seen after comparing the concentration of periostin in periodontitis as well as peri-implantitis groups (P > 0.05).

Conclusion

The present study analyzed periostin levels in gingival crevicular fluid obtained from patients diagnosed with periodontitis and sulcular fluid obtained from the sulcus around implants. Early biological markers or indicators of inflammation should be studied to determine the prognosis of treatment apart from the clinical assessment for the patient's benefit.

A novel nonsurgical therapy for peri-implantitis using focused pulsed electromagnetic field: A pilot randomized double-blind controlled clinical trial

Pulsed electromagnetic field (PEMF) therapy modulates the immune response and is successfully used in orthopedics to treat osteoarthritis and improve bone regeneration. This may suggest that this treatment may consequently reduce peri-implant soft tissue inflammation and marginal bone loss. To compare clinical, radiographic, and immunological results following nonsurgical treatment for peri-implantitis with or without PEMF therapy. Patients with peri-implantitis were included: pocket probing depth (PPD) between 6 and 8 mm with bleeding on probing (BOP); crestal bone loss between 3 and 5 mm. A novel healing abutment that contained active (test) or inactive (control) PEMF was connected. PEMF was administered via the abutment at exposure ratio of 1/500-1/5000, intensity: 0.05-0.5 mT, frequency: 10-50 kHz for 30 days. Nonsurgical mechanical implant surface debridement was performed. Patients were examined at baseline, 1 and 3 months. Clinical assessment included: plaque index, BOP, PPD, recession, and bone crest level which was radiography measured. Samples of peri-implant crevicular fluid were taken to analyze interleukin-1β (IL-1β). Twenty-three patients (34 implants; 19 control, 15 test) were included. At the follow-up, mean crestal bone loss was lower in the test group at 1 and 3 months (2.48 mm vs. 3.73 mm, p < 0.05 and 2.39 vs. 3.37, p < 0.01). IL-1β levels were also lower in the test group at 2 weeks (72.86 pg/mL vs. 111.7, p < 0.05). Within all the limitation of this preliminary study, the test group improved clinical parameters after a short-term period compared to the control group.

Effectiveness of two photosensitizer-mediated photodynamic therapy for treating moderate peri-implant infections in type-II diabetes mellitus patients: A randomized clinical trial

PURPOSE

This study evaluated the impact of Fox Green (FG) against methylthioninium chloride (MTC)-facilitated photodynamic therapy (PDT) as an adjunctive to manual scaling (MS) on the peri‑implant clinical and cytokine parameters in type-2 diabetes mellitus (DM) patients with peri‑implantitis.

METHODS

Patients were divided into group-A comprising 13 patients who received adjunctive FG-PDT using a diode laser (wavelength: 810 nm; irradiation power: 300 mW; irradiation time: 30 s; fluence: 56 Jcm-2), group-B comprising 12 patients who received adjunctive MTC-PDT using a diode laser (wavelength: 660 nm; irradiation power: 100 mW; irradiation time: 120 s/site; fluence: 30 Jcm-2), and group-C comprising 13 patients who received MS alone [control group]). After diagnosing the diabetics with peri‑implantitis (established on eligibility criteria), a structured questionnaire was used to gather the information of the participants. Plaque (PS) and bleeding scores (BS), along with peri‑implant probing scores (PPS) and peri‑implant bone loss (PIBL), together with immunological variables (interleukin [IL]-6, tumor necrosis factor-alpha [TNF-α], and advanced glycation end products [AGEs]) were measured in all study group participants at baseline, 3-month, and 6-month follow-ups.

RESULTS

A significant reduction was observed for PS, BS, and PPS within all tested groups at each follow-up visits compared from their baseline values (p<0.05). However, a substantial decrease in PIBL was observed in all study group patients at 6-month follow-up as compared to 3-month follow-up (p<0.05). Regarding the levels of IL-6 and TNF-α, a substantial reduction was observed in all study groups until 6-month from their baseline scores (p<0.05). However, no changes were observed in the levels of AGEs in any group at either visit (p>0.05).

CONCLUSION

In DM patients with periimplantitis, adjunctive FG-PDT and MTC-PDT exhibited comparable outcomes in terms of peri‑implant clinical as well as pro-inflammatory characteristics than MS alone among peri‑implantitis patients with DM.

Clinical, microbiological and osteoimmunological findings in different peri-implant conditions - A cross-sectional study

OBJECTIVES

The aim of this study was to assess the prevalence of certain microbiota and their potential correlation with clinical parameters, expression of proinflammatory cytokines, Notch signalling pathway molecules and bone remodelling mediators among different peri-implant conditions.

MATERIALS AND METHODS

Included participants had at least one dental implant minimally 1 year in function. They were divided into peri-implantitis (PI), peri-implant mucositis (PM) and healthy implants (HIs) groups. Prevalence of P. ginigvalis, Fusobacterium spp., EBV and C. albicans was detected in participants' crevicular fluid (CF) using quantitative real-time polymerase chain reaction, different markers' expression, as well as clinical data, were correlated with the microbial presence.

RESULTS

CF samples taken from one chosen implant from each of the 102 participants were analyzed. Significantly higher levels of P. gingivalis were found in PI compared with HI (p = .012) and PM (p = .026). Fusobacterium spp. was also more prevalent in PI (p = .041) and PM (0.008) than in HI. P. gingivalis was a predictor of PPDi (p = .011, R2  = 0.063) and CALi (p = .049, R2  = 0.038). A positive correlation was found in PI for the level of Fusobacterium spp. and TNFα expression (ρ = 0.419, p = .017) while in PM, P. gingivalis and Notch 2 expression were correlated (ρ = 0.316, p = .047).

CONCLUSIONS

P. gingivalis appears to be involved in the osteolysis in patients with PI, while the positive correlation of its level with Notch 2 expression in patients with PM suggests a potential involvement of P. gingivalis in the progression of PM into PI.

The efficacy of different implant surface decontamination methods using spectrophotometric analysis: an in vitro study

PURPOSE

Various methods have been proposed to achieve the nearly complete decontamination of the surface of implants affected by peri-implantitis. We investigated the in vitro debridement efficiency of multiple decontamination methods (Gracey curettes [GC], glycine air-polishing [G-Air], erythritol air-polishing [E-Air] and titanium brushes [TiB]) using a novel spectrophotometric ink-model in 3 different bone defect settings (30°, 60°, and 90°).

METHODS

Forty-five dental implants were stained with indelible ink and mounted in resin models, which simulated standardised peri-implantitis defects with different bone defect angulations (30°, 60°, and 90°). After each run of instrumentation, the implants were removed from the resin model, and the ink was dissolved in ethanol (97%). A spectrophotometric analysis was performed to detect colour remnants in order to measure the cumulative uncleaned surface area of the implants. Scanning electron microscopy images were taken to assess micromorphological surface changes.

RESULTS

Generally, the 60° bone defects were the easiest to debride, and the 30° defects were the most difficult (ink absorption peak: 0.26±0.04 for 60° defects; 0.32±0.06 for 30° defects; 0.27±0.04 for 90° defects). The most effective debridement method was TiB, independently of the bone defect type (TiB vs. GC: P<0.0001; TiB vs. G-Air: P=0.0017; TiB vs. GE-Air: P=0.0007). GE-Air appeared to be the least efficient method for biofilm debridement.

CONCLUSIONS

T-brushes seem to be a promising decontamination method compared to the other techniques, whereas G-Air was less aggressive on the implant surface. The use of a spectrophotometric model was shown to be a novel but promising assessment method for in vitro ink studies.

Optimized titanium dioxide nanotubes for dental implants: Estimation of mechanical properties and effects on the biological behaviors of human gingival fibroblasts and oral bacteria

The long-term successes of implant restorations rely on both appropriate osseointegration and robust soft tissue integration (STI). Numerous studies have reported that titanium dioxide nanotube (TNT) arrays formed by electrochemical anodization (EA) can promote early osteogenesis, but the mechanical stability of such modifications is often ignored and remains underexplored. In addition, relatively little research has been done on their effects on soft tissues integration. In this study, we developed mechanically robust TNT arrays using an optimized EA system. Subsequently, we immobilized a peptide, specifically D-amino K122-4, onto the anodized TNTs via polydopamine (PDA) films to enhance their mechanical properties. Surface morphology and composition were characterized by scanning electron microscopy (SEM), atomic force microscopy, and X-ray photoelectron spectroscopy. Mechanical properties, including the elastic modulus and hardness of TNTs modified Ti surfaces, were assessed using the nano-indention test. The adhesive strength of TNTs films to the substrate was measured using the nano scratch test. Furthermore, we evaluated the adhesion, spreading, and proliferation of human gingival fibroblasts (HGFs) and periodontal pathogenic bacteria such as Streptococcus mutans (S.m) and F. nucleatum (F.n) on the surface. Results showed that the elastic modulus, hardness, and adhesive strength of anodized TNTs were significantly enhanced by the incorporation of the D-amino K122-4 peptide. Live-dead staining and SEM observation suggested a decreased surface colonization by both bacterial species. The antibacterial rate of S.m and F. n was 81.5% and 71.7%, respectively, evaluated by colony counting method. Additionally, results of CCK8 assay showed that modified TNTs slightly stimulated HGFs attachment and proliferation while producing enhanced fluorescence of integrin β1 and F-actin, confirmed by laser confocal microscopy observation. Thus, D-amino K122-4 biofunctionalized TNTs present significantly improved mechanical properties, and the mechanically robust structures modulate HGFs proliferation and alignment, resulting in decreased bacteria growth. This novel strategy has the potential to create a surface coating for implants that exhibits superior mechanical robustness and enhanced surface-to-implant interactions.

Dental Restorations

Fulfilling a patient's request for a healthy, functional and esthetic smile represents a daily challenge for dental practitioners [...].

Insight Into the Laboratory Diagnosis of Periimplantitis Using Reactive Oxygen Metabolite Levels - A Biochemical Study

Aim The study aims to substantiate the quantitative role of the predominant periodontopathogen (Porphyromonas gingivalis) associated with peri-implantitis and evaluate the reactive oxygen metabolite levels in peri-implantitis patients. Methodology A total of 40 participants were taken from the department of periodontology, Thai Moogambigai Dental College and Hospital, Chennai, and divided into groups I (control) and II (test). Group I included 20 participants with healthy peri-implant tissue, and group II included 20 participants with infected peri-implant tissues. The predominant periodontopathogen was detected by using a quantitative real-time polymerase chain reaction. Samples (gingival crevicular fluid (GCF), saliva, and plasma) were collected, and a biochemical assay was conducted for reactive oxygen metabolites (ROM) analysis in healthy implants (control group) and peri-implantitis conditions (test group). ROM levels of the patients were statistically analyzed. Results The qualitative and quantitative profiles of Porphyromonas gingivalis (P. gingivalis) associated with Peri-implantitis were analyzed, and the levels of ROM in periimplantitis patients were assessed. The study results substantiate the quantitative picture of Porphyromonas gingivalis in the detection of periimplantitis. The saliva and GCF samples showed significant differences in ROM levels between the test and control groups. Conclusion This is one of the few studies to detect the predominant bacterial pathogen associated with peri-implantitis and assess the ROM levels in periimplantitis patients. The study gives a correlation between the periopathogens and ROM levels, thereby facilitating the attainment of the best possible treatment options.

Association of Patient Anthropometric Measurements and Dental Implant Treatment

Background

Dental implants are currently one of the most preferred treatment modalities for replacing missing teeth, as they are the most comparable to natural teeth. Even so, satisfaction with such treatment may differ depending on patient nature. The aim of this article was to examine the relationships between different anthropometric measurements on dental implant patient's satisfaction.

Methods and Material

Self-administered questionnaire (structured questions) were given to patients who had dental implant treatment to evaluate their satisfaction level with dental-implant treatment. Different anthropometric measurements were taken: body height; weight; body mass index (BMI); body composition; waist/hip ratio; and circumferences at the waist, hip, and neck.

Results

The overall BMI was 28.9±4.7 kg/m², there was a highly-significant difference in patient satisfaction among the different BMI groups (P< 0.000). The significant difference in most of those groups was between the obese group and the other groups. For neck circumference and waist/hip ratio, a significance difference between the normal weight and obese groups (P< 0.000) was found, while for percentage of muscle, the differences were between the overweight and obese groups (P< 0.000). According to BMI groups a highly significant difference in many patient satisfaction domains were found (P< 0.000). These significant differences were between the obese group and non-obese groups for most aspects of patient satisfaction. For patient satisfaction with final appearance, the normal BMI group differed significantly from the overweight BMI group (P=0.013). Additionally, for patient satisfaction with dentist performance and communication, the overweight BMI group showed significantly higher satisfaction than the normal BMI group (P=0.019). Body measurements were correlated negatively with overall patient satisfaction, and positively with satisfaction with prosthesis.

Conclusion

The obese group patients had the lowest rate of patient satisfaction. BMI and other body measurements can be used to predict patient satisfaction with the outcome of dental implant treatment.

Peri-implantitis after 40 years: Evidence, mechanisms, and implications: A mapping review

STATEMENT OF PROBLEM

The high prevalence of peri-implantitis (PI) continues to plague patients and the disease is resistant to present treatment regimens. An analysis of the available research is lacking.

PURPOSE

Given the abundance and diversity of research on the topic of PI, the purpose of this mapping review was to synthesize the literature on the prevention of PI, the histopathology of the disease, the state of present therapeutics, and any emerging treatments.

MATERIAL AND METHODS

An extensive literature search was undertaken by using the electronic databases of PubMed, Web of Science, and Science Direct. The keyword strings were peri-implantitis, dental implant, risk assessment, histopathology, prosthesis design, and treatment. The filters applied were time interval from 2000 to 2002; language, English.

RESULTS

A total of 3635 articles were taken from PubMed, 3686 articles from Web of Science, and 2450 articles from Science Direct. After applying the inclusion and exclusion criteria to the titles and abstracts of selected investigations, 214 studies were retrieved.

CONCLUSIONS

The evidence reflects a concerning incidence of PI, without a predictable treatment protocol. An in-depth patient risk assessment considering risk modification, emphasis on surgical and restorative expertise, and strict recall and maintenance is essential to minimize PI.

Non-Surgical Therapy and Oral Microbiota Features in Peri-Implant Complications: A Brief Narrative Review

The therapeutic discretion in cases of peri-implantitis should take into account the limits and advantages of specific therapeutic itineraries tailored according to each clinical case and each individual patient. This type of oral pathology emphasizes the complex classification and diagnostic issues coupled with the need for targeted treatments, in light of the oral peri-implant microbiota changes. This review highlights the current indications for the non-surgical treatment of peri-implantitis, describing the specific therapeutic efficacy of different approaches and discussing the more appropriate application of single non-invasive therapies The non-surgical treatment choice with antiseptics or antibiotics (single or combined, local, or systemic) for short courses should be considered on a case-by-case basis to minimize the incidence of side effects and concomitantly avoid disease progression.

Peri-implant crevicular fluid and serum levels of soluble ST2 in peri-implant diseases: A pilot study

BACKGROUND AND OBJECTIVE

Soluble ST2 (sST2) is a current biomarker of cardiovascular disease. It is used to predict susceptibility to cardiovascular diseases and to analyze their prognosis. Serum sST2 level increases in inflammatory diseases such as periodontitis. However, the level of sST2 in peri-implant diseases and crevicular fluid has not been investigated yet. Thus, the aim of this cross-sectional study is to analyze the level of sST2 in peri-implant health and diseases.

METHODS

Sixty-nine participants were divided into 3 groups as peri-implant health (PH), peri-implant mucositis (PM), and peri-implantitis (P-I). Peri-implant crevicular fluid (PICF) and serum samples were collected from each participant. The levels of sST2 and IL-6 in PICF and sST2, IL-6, and CRP in serum were compared between the groups. Pocket depth (PD), modified bleeding index (mBI), modified plaque index (mPI), keratinized mucosa index (KTW), and gingival/mucosal recession (REC) were recorded as clinical parameters. Biomarkers in the serum and PICF were analyzed by ELISA kit.

RESULTS

Sixty-nine patients were included in the study. The differences in the following parameters were statistically significant between groups: age (p = .009), implant function time (p = .027), PD (p < .001), mBI (p < .001), mPI (p < .001), and KTW (p = .043). The PICF volume of P-I and PM groups were statistically higher than PH (p < .001). The amount of sST2 in P-I and PM groups were higher than PH (p = .043). Serum CRP was higher in the P-I group than in other groups (p = .034). There were no significant differences in serum sST2 (p = .247) and IL-6 (p = .110) levels between groups.

CONCLUSION

The PICF levels of sST2 were significantly higher in PM and P-I groups compared to the healthy group. However, no significant difference was observed between the groups in terms of serum sST2 level.

In-Vitro Biofilm Removal Efficacy Using Water Jet in Combination with Cold Plasma Technology on Dental Titanium Implants

Peri-implantitis-associated inflammation can lead to bone loss and implant failure. Current decontamination measures are ineffective due to the implants' complex geometry and rough surfaces providing niches for microbial biofilms. A modified water jet system (WaterJet) was combined with cold plasma technology (CAP) to achieve superior antimicrobial efficacy compared to cotton gauze treatment. Seven-day-old multi-species-contaminated titanium discs and implants were investigated as model systems. The efficacy of decontamination on implants was determined by rolling the implants over agar and determining colony-forming units supported by scanning electron microscopy image quantification of implant surface features. The inflammatory consequences of mono and combination treatments were investigated with peripheral blood mononuclear cell surface marker expression and chemokine and cytokine release profiles on titanium discs. In addition, titanium discs were assayed using fluorescence microscopy. Cotton gauze was inferior to WaterJet treatment according to all types of analysis. In combination with the antimicrobial effect of CAP, decontamination was improved accordingly. Mono and CAP-combined treatment on titanium surfaces alone did not unleash inflammation. Simultaneously, chemokine and cytokine release was dramatically reduced in samples that had benefited from additional antimicrobial effects through CAP. The combined treatment with WaterJet and CAP potently removed biofilm and disinfected rough titanium implant surfaces. At the same time, non-favorable rendering of the surface structure or its pro-inflammatory potential through CAP was not observed.

Silver Nanoparticles Produced by Laser Ablation and Re-Irradiation Are Effective Preventing Peri-Implantitis Multispecies Biofilm Formation

Implant-associated infection due to biofilm formation is a growing problem. Given that silver nanoparticles (Ag-NPs) have shown antibacterial effects, our goal is to study their effect against multispecies biofilm involved in the development of peri-implantitis. To this purpose, Ag-NPs were synthesized by laser ablation in de-ionized water using two different lasers, leading to the production of colloidal suspensions. Subsequently, part of each suspension was subjected to irradiation one and three times with the same laser source with which it was obtained. Ag-NPs were immobilized on the surface of titanium discs and the resultant materials were compared with unmodified titanium coupons. Nanoparticles were physico-chemically analysed to determine their shape, crystallinity, chemical composition, and mean diameter. The materials were incubated for 90 min or 48 h, to evaluate bacterial adhesion or biofilm formation respectively with Staphylococcus aureus or oral mixed bacterial flora composed of Streptococcus oralis, Actinomyces naeslundii, Veionella dispar, and Porphyromonas gingivalis. Ag-NPs help prevent the formation of biofilms both by S. aureus and by mixed oral bacterial flora. Nanoparticles re-irradiated three times showed the biggest antimicrobial effects. Modifying dental implants in this way could prevent the development of peri-implantitis.

Psychological risk indicators for peri-implantitis: A cross-sectional study

AIM

The aim of this analytical cross-sectional study was to evaluate the association between peri-implantitis and psychological distress, and potentially related/mediating factors such as general health, bruxism, and lifestyle factors.

MATERIALS AND METHODS

Patients who received dental implants at a private practice in the Netherlands between January 2011 and January 2014 were recalled on a 5-year clinical and radiographic follow-up examination. Presence of peri-implantitis was examined, and patients completed questionnaires measuring psychological distress (Symptom Checklist [SCL]-90), bruxism, general health, and lifestyle factors. Associations between the self-reported factors and peri-implantitis were analysed with univariate and multivariate logistic regression models.

RESULTS

A total of 230 patients (with 347 implants) were included in the analysis. Prevalence of (mild to severe) peri-implantitis was 30% (69 patients). Variables that showed a significant univariable association with peri-implantitis (p < .10) were the SCL-90 subdomain depression, smoking, current medical treatment, and lung problems. In the multivariate regression analysis, depression was the only variable that was significantly associated with peri-implantitis (p < .05).

CONCLUSIONS

The presence of depressive symptoms is a risk indicator for peri-implantitis. Recognizing the potential negative impact of depressive symptoms may allow for better identification of high-risk patients.

Comparison of Different Chemical and Mechanical Modalities for Implant Surface Decontamination: Activity against Biofilm and Influence on Cellular Regrowth—An In Vitro Study

Objectives

The aim of this in vitro study was to compare the efficacy of chemical and mechanical methods for decontamination of titanium dental implant surfaces previously infected with polymicrobial biofilms in a model simulating a peri-implant defect. Furthermore, the effect of each decontamination protocol on MG-63 osteoblast-like cells morphology and adhesion to the treated implants was assessed.

Background

Peri-implantitis is a growing issue in dentistry, and evidence about implant surface decontamination procedures is lacking and inconclusive.

Methods

A total of 40 previously biofilm-contaminated implants were placed into a custom-made model simulating a peri-implant defect and randomly assigned to five treatment groups: (C) control (no treatment); (AW) air abrasion without any powder; (ESC) air abrasion with powder of erythritol, amorphous silica, and 0.3% chlorhexidine; (HBX) decontamination with a sulfonic/sulfuric acid solution in gel; and (HBX + ESC) a combination of HBX and ESC. Microbiological analysis was performed on five implants per treatment group, and the residual viable bacterial load measured in log 10 CFU/mL was counted for each bacterial strain and for the total number of colonies. The remaining three implants per group and three noncontaminated (NC) implants were used to assess surface biocompatibility using a scanning electron microscope and a backscattered electron microscope after seeding with MG-63 cells.

Results

A significant decontaminant effect was achieved using HBX or HBX + ESC, while no differences were observed among other groups. The percentage of implant surface covered by adherent MG-63 cells was influenced by the treatment method. Progressive increases in covered surfaces were observed in groups C, AW, ESC, HBX, HBX + ESC, and NC.

Conclusions

A combination of mechanical and chemical decontamination may provide more predictable results than mechanical cleaning alone.

Antibacterial Adhesion Strategy for Dental Titanium Implant Surfaces: From Mechanisms to Application

Dental implants are widely used to restore missing teeth because of their stability and comfort characteristics. Peri-implant infection may lead to implant failure and other profound consequences. It is believed that peri-implantitis is closely related to the formation of biofilms, which are difficult to remove once formed. Therefore, endowing titanium implants with anti-adhesion properties is an effective method to prevent peri-implant infection. Moreover, anti-adhesion strategies for titanium implant surfaces are critical steps for resisting bacterial adherence. This article reviews the process of bacterial adhesion, the material properties that may affect the process, and the anti-adhesion strategies that have been proven effective and promising in practice. This article intends to be a reference for further improvement of the antibacterial adhesion strategy in clinical application and for related research on titanium implant surfaces.

Applications of Biodegradable Magnesium-Based Materials in Reconstructive Oral and Maxillofacial Surgery: A Review

Reconstruction of defects in the maxillofacial region following traumatic injuries, craniofacial deformities, defects from tumor removal, or infections in the maxillofacial area represents a major challenge for surgeons. Various materials have been studied for the reconstruction of defects in the maxillofacial area. Biodegradable metals have been widely researched due to their excellent biological properties. Magnesium (Mg) and Mg-based materials have been extensively studied for tissue regeneration procedures due to biodegradability, mechanical characteristics, osteogenic capacity, biocompatibility, and antibacterial properties. The aim of this review was to analyze and discuss the applications of Mg and Mg-based materials in reconstructive oral and maxillofacial surgery in the fields of guided bone regeneration, dental implantology, fixation of facial bone fractures and soft tissue regeneration.

MicroRNA sequence and function analysis in peri-implantitis and periodontitis: An animal study

OBJECTIVE

To compare miRNA expression levels and predict relevant target genes and signaling pathways in peri-implantitis and periodontitis.

BACKGROUND

There are many differences between periodontitis and peri-implantitis. An understanding of the similarities and differences in the transcriptional patterns of these diseases, as well as the molecular mechanisms, is beneficial for the development of management strategies.

MATERIALS AND METHODS

Rat models of periodontitis (PD, n = 6) and peri-implantitis (PI, n = 5) were established by ligation. Implantation without ligation (PIC, n = 5) and normal rats (PDC, n = 6) were used as controls. Micro-CT was used to confirm the successful establishment of the model. Gingiva was harvested for miRNA transcriptome sequencing, and the results were confirmed by qRT-PCR. miRNA target genes were predicted with miRTarBase. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed.

RESULTS

Sixty-nine miRNAs were differentially expressed in PI vs. PD, 105 were differentially expressed in PI vs. PIC, and 70 were differentially expressed in PD vs. PDC (log₂ FC ≥1 and padj <0.05). The upregulated genes in all three comparisons were mostly involved in the biological process response to stimulus, whereas most of the downregulated genes were involved in nervous system development (p < .01). The upregulated genes in PI vs. PD and PI vs. PIC were involved in Toll-like receptor signaling and RIG-I-like signaling. The upregulated genes in PI vs. PD were involved in T- and B-cell receptor signaling, apoptosis, and osteoclast differentiation. Focal adhesion was downregulated in all three comparisons, and adherens junction was downregulated in PI vs. PD and PD vs. PDC (p < .1).

CONCLUSION

This study showed differences in the miRNA expression profiles between peri-implantitis and periodontitis and annotated the possible target genes and molecular mechanisms; this study could lay a foundation for the development of management strategies.

Transcription Factor AhR, Cytokines IL-6 and IL-22 in Subjects with and without Peri-Implantitis: A Case Control-Study

Peri-implantitis is a plaque-associated condition characterized by mucosal inflammation and subsequent progressive loss of supporting bone; it is caused by bacterial biofilm, but the host response triggered by bacterial stimulation promotes the release of cells and mediators that culminate in tissue destruction. The Aryl-hydrocarbon Receptor (AhR) is associated with IL-22 production by Th22 and Th17 CD4+ Th cells. The presence of IL-6 may promote the Th22 phenotype. The present case-control study evaluated the gene expression of AhR, IL-22, and IL-6 in the peri-implant tissues of healthy and peri-implantitis patients. Tissue biopsies were collected from thirty-five volunteers (15 healthy and 20 with peri-implantitis). A real-time PCR reaction was utilized to assess the AhR, IL-22, and IL-6 gene expression levels relative to the reference gene (GAPDH). The results were analyzed using the Mann-Whitney test with a significance level of 5%. Higher levels of gene expression of AhR and IL-6 were detected in peri-implantitis tissues. The IL-22 gene expression levels did not differ between groups. In conclusion, higher gene expression levels for AhR and IL-6 were detected in the soft tissues of peri-implantitis patients. IL-22 did not vary between conditions, which may indicate the loss of the immunomodulatory role of IL-22 in periimplantitis.

Effect of sterile tetracycline ophthalmic ointment as an adjuvant to mechanical debridement on the treatment of peri-implantitis: A randomized controlled clinical trial

Background

Peri-implantitis is an infectious disease that affects the tissues around dental implants, with clinical signs of inflammation and irreversible loss of supporting bone. This study aimed to compare the effect of sterile topical tetracycline ophthalmic ointment as an adjuvant to mechanical debridement with mechanical debridement alone in the treatment of peri-implantitis.

Methods

In this single-blind randomized clinical trial, 32 patients (16 patients in each group) with peri-implantitis were treated topically using sterile tetracycline ophthalmic ointment. Four clinical parameters, including modified bleeding index (mBI), modified plaque index (mPI), probing depth (PD), and clinical attachment level (CAL), were measured at baseline and at 3- and 6-month follow-up intervals.

Results

PD reduction was statistically significant after 3 and 6 months in the test and control groups (P=0.001). Also, mPI and mBI reduction rates were significant in the test and control groups (P=0.001) after 3 and 6 months. However, in all the samples in the two groups, the mean of CAL before and after treatment was constant, with no significant difference (P>0.05).

Conclusion

Using sterile ocular tetracycline ointment could be an adjunctive treatment in improving and enhancing the therapeutic effects of mechanical debridement in the treatment of peri-implantitis. (IRCT20210909052418N1)

Efficiency of biofilm removal by combination of water jet and cold plasma: an in-vitro study

Background

Peri-implantitis therapy is a major problem in implantology. Because of challenging rough implant surface and implant geometry, microorganisms can hide and survive in implant microstructures and impede debridement. We developed a new water jet (WJ) device and a new cold atmospheric pressure plasma (CAP) device to overcome these problems and investigated aspects of efficacy in vitro and safety with the aim to create the prerequisites for a clinical pilot study with these medical devices.

Methods

We compared the efficiency of a single treatment with a WJ or curette and cotton swab (CC) without or with adjunctive use of CAP (WJ + CAP, CC + CAP) to remove biofilm in vitro from rough titanium discs. Treatment efficacy was evaluated by measuring turbidity up to 72 h for bacterial re-growth or spreading of osteoblast-like cells (MG-63) after 5 days with scanning electron microscopy. With respect to application safety, the WJ and CAP instruments were examined according to basic regulations for medical devices.

Results

After 96 h of incubation all WJ and CC treated disks were turbid but 67% of WJ + CAP and 46% CC + CAP treated specimens were still clear. The increase in turbidity after WJ treatment was delayed by about 20 h compared to CC treatment. In combination with CAP the cell coverage significantly increased to 82% (WJ + CAP) or 72% (CC + CAP), compared to single treatment 11% (WJ) or 10% (CC).

Conclusion

The newly developed water jet device effectively removes biofilm from rough titanium surfaces in vitro and, in combination with the new CAP device, biologically acceptable surfaces allow osteoblasts to grow. WJ in combination with CAP leads to cleaner surfaces than the usage of curette and cotton swabs with or without subsequent plasma treatment. Our next step will be a clinical pilot study with these new devices to assess the clinical healing process.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-022-02195-1.

Staphylococcus aureus enhances gelatinase activities in monocytic U937 cells and in human gingival fibroblasts

Background/purpose

Staphylococcus aureus (S. aureus) has been suggested to be an initiative pathogen in peri-implantitis because of the solid affinity to titanium. However, the detail pathogenesis for the peri-implantitis initiation by S. aureus is still lacking. This study aimed to in vitro examine the gelatinases’ activities of monocytic U937 cell and human gingival fibroblast after challenges with S. aureus lipoteichoic acid (LTA) and peptidoglycan (PGN).

Materials and methods

Releases of gelatinases, including matrix metalloproteinase (MMP)-2 and −9, from cells were measured by zymography. The releases were further examined after being given the S. aureus LTA/PGN. Roles of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways on the enzyme releases were examined by administrating inhibitors.

Results

S. aureus LTA and PGN increased the activities of pro-MMP-9 from U937 cells and pro-MMP-2 and MMP-2 from gingival fibroblasts. By giving the NF-κB inhibitor, the enhanced gelatinase activities in both cells were attenuated. In U937 cells, the enhanced pro-MMP-9 could further be attenuated by MAPK inhibitors, including extracellular signal-regulated kinase 1 and 2 (ERK1/2), P38 MAPK, and c-Jun N-terminal kinase (JNK) inhibitors; however, the attenuation by MAPK inhibitors could not be observed for MMP-2 in gingival fibroblasts. Nevertheless, in gingival fibroblasts, the pro-MMP-2 could be attenuated by JNK inhibitor.

Conclusion

S. aureus could enhance gelatinase activities of gingival fibroblasts and U937 cells, via NF-κB. The MAPK pathway was also involved in MMP-9 activity of U937 cells; however, the involvement of MAPK in MMP-2 activity of gingival fibroblasts was questioned.

Domiciliary Use of Chlorhexidine vs. Postbiotic Gels in Patients with Peri-Implant Mucositis: A Split-Mouth Randomized Clinical Trial

Peri-implant mucositis is a pathological condition characterized by an inflammatory process in the peri-implant soft tissues. Progression to peri-implantitis takes place in case of peri-implant bone resorption. Recently, an aid for non-surgical treatment by mechanical debridement (SRP) has been identified in probiotics. As there are no recent studies regarding their use for peri-implant mucositis, the aim of this study was to test a new postbiotic gel for this clinical condition. A split-mouth randomized clinical trial was performed. Twenty patients undergoing SRP were randomly assigned to two treatments based on the following oral gels: chlorhexidine-based Curasept Periodontal Gel (Group 1) and postbiotic-based Biorepair Parodontgel Intensive (Group 2). At baseline (T0) and after three (T1) and six (T2) months, the following peri-implant mucositis indexes were recorded: Probing Pocket Depth (PPD), Plaque Index (PI), Gingival Bleeding Index (GBI), Bleeding Score (BS), Marginal Mucosal Condition (MMC). A significant decrease is reported for both postbiotic and chlorhexidine for all peri-implant mucositis indices studied. Quite the opposite, no significant variation was present in intergroup comparisons. Greater improvements for BS, GBI and MMC inflammatory indices of the postbiotic gel compared to chlorhexidine suggest the importance of further studies to investigate the relevance of the product alone.

Corrosion Behavior of Titanium Dental Implants with Implantoplasty

The procedure generally used to remove bacterial biofilm adhering to the surface of titanium on dental implants is implantoplasty. This treatment is based on the machining of the titanium surface to remove bacterial plaque. In this study, we used 60 grade 4 titanium implants and performed the implantoplasty protocol. Using X-ray diffraction, we determined the stresses accumulated in each of the as-received, machined and debris implants. The resistance to corrosion in open circuit and potentiodynamically in physiological medium has been determined, and the corrosion potentials and intensities have been determined. Tests have been carried out to determine ion release by ICP-MS at different immersion times. The results show that the corrosion resistance and the release of titanium ions into the medium are related to the accumulated energy or the degree of deformation. The titanium debris exhibit compressive residual stresses of −202 MPa, the implant treated with implantoplasty −120 MPa, and as-received −77 MPa, with their corrosion behavior resulting in corrosion rates of 0.501, 0.77, and 0.444 mm/year, respectively. Debris is the material with the worst corrosion resistance and the one that releases the most titanium ions to the physiological medium (15.3 ppb after 21 days vs. 7 ppb for as-received samples). Pitting has been observed on the surface of the debris released into the physiological environment. This behavior should be taken into account by clinicians for the good long-term behavior of implants with implantoplasty.

Airflow for initial nonsurgical treatment of peri-implantitis: A systematic review and meta-analysis

BACKGROUND

Nonsurgical treatment of peri-implantitis may help in reducing microbial load and inflammatory parameters. The potential clinical benefits of using different treatment approaches, in the initial nonsurgical treatment phase, particularly the airflow, are still not clear. The aim of this systematic review and meta-analyses was to evaluate the outcomes of nonsurgical treatment of peri-implantitis using airflow method in terms of changes in periodontal parameters, peri-implant marginal bone level, postoperative pain/discomfort, and patient satisfaction.

METHODS

Electronic databases were searched to identify randomized controlled trials (RCTs) that compared airflow with mechanical debridement using ultrasonic/curettes. The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool. Data were analyzed using a statistical software program.

RESULTS

A total of 316 studies were identified, of which, five RCTs with 288 dental implants in 174 participants were included. Overall meta-analysis showed more reduction in probing pocket depths at 1-3 months (mean difference [MD] -0.23; 95% confidence interval [CI] -0.50-0.05; p = 0.10) and 6 months (MD -0.04; 95% CI -0.34 to 0.27; p = 0.80) in favor of airflow, but the difference was not statistically significant. The use of airflow was associated with significant reduction in bleeding on probing and increase in peri-implant mucosal recession. The differences in plaque score, peri-implant marginal bone level changes, and patient reported outcomes between airflow and mechanical debridement were not statistically significant.

CONCLUSIONS

The short-term clinical and radiographic outcomes following nonsurgical treatment of peri-implantitis using airflow or mechanical debridement were comparable. The airflow has short-term positive effects on reducing bleeding on probing. Further evidence from RCTs are still required to substantiate the current findings.

Influence of Periodontitis, Implant, and Prosthesis Characteristics on the Peri-Implant Status: A Cross-Sectional Study

Background

The association between peri-implant diseases and the periodontal, implant, and prosthesis characteristics has been characterized in various ways.

Purpose

The aim of this study was to evaluate the link between the peri-implant and periodontal status and the influence of implant and prosthesis parameters during implant follow-up.

Materials and Methods

One hundred and seven patients with a total of 310 implants that had at least one year of function who were attending periodontal and implant maintenance at a university clinic setting were included in this cross-sectional study. The demographic, periodontal, peri-implant tissue, implant, and prosthesis parameters were recorded. A pocket depth > 4 mm with bleeding on probing defined periodontal/peri-implant soft tissue diseased sites. Analyses were performed at the patient and implant levels using univariable and multivariable mixed regression analysis.

Results

The mean implant follow-up was 7.22 years. At the patient level, the bleeding on probing and pocket depth measurements were more pronounced around the implant than around the teeth. The opposite was observed for plaque and the clinical attachment levels. At the implant level, multivariable analysis showed that the periodontal and corresponding peri-implant tissue parameters, such as diseased sites, were closely related. The implant location, bone level, and number were selectively associated with the implant bone level, while cemented retention and emergence restoration profile influenced the implant pocket depth.

Conclusions

The present study suggested that clinical peri-implant and periodontal soft tissue statuses were different, which could be a consequence of the initial implant and prosthesis healing process. However, during implant follow-up, the peri-implant parameters were predominantly associated with their corresponding periodontal parameters regardless of an association with the implant and prosthesis characteristics. This trial is registered with ClinicalTrials.gov ID: NCT03841656.

Relevant Aspects of Piranha Passivation in Ti6Al4V Alloy Dental Meshes

Passivation of titanium alloy dental meshes cleans their surface and forms a thin layer of protective oxide (TiO2) on the surface of the material to improve resistance to corrosion and prevent release of ions to the physiological environment. The most common chemical agent for the passivation process of titanium meshes is hydrochloric acid (HCl). In this work, we introduce the use of Piranha solution (H2SO4 and H2O2) as a passivating and bactericidal agent for metallic dental meshes. Meshes of grade 5 titanium alloy (Ti6Al4V) were tested after different treatments: as-received control (Ctr), passivated by HCl, and passivated by Piranha solution. Physical-chemical characterization of all treated surfaces was carried out by scanning electron microscopy (SEM), confocal microscopy and sessile drop goniometry to assess meshes’ topography, elemental composition, roughness, wettability and surface free energy, that is, relevant properties with potential effects for the biological response of the material. Moreover, open circuit potential and potentiodynamic tests were carried out to evaluate the corrosion behavior of the differently-treated meshes under physiological conditions. Ion release tests were conducted using Inductively Coupled Plasma mass spectrometry (ICP-MS). The antibacterial activity by prevention of bacterial adhesion tests on the meshes was performed for two different bacterial strains, Pseudomonas aeruginosa (Gram-) and Streptococcus sanguinis (Gram+). Additionally, a bacterial viability study was performed with the LIVE/DEAD test. We complemented the antibacterial study by counting cells attached to the surface of the meshes visualized by SEM. Our results showed that the passivation of titanium meshes with Piranha solution improved their hydrophilicity and conferred a notably higher bactericidal activity in comparison with the meshes passivated with HCl. This unique response can be attributed to differences in the obtained nanotextures of the TiO2 layer. However, Piranha solution treatment decreased electrochemical stability and increased ion release as a result of the porous coating formed on the treated surfaces, which can compromise their corrosion resistance. Framed by the limitations of this work, we conclude that using Piranha solution is a viable alternative method for passivating titanium dental meshes with beneficial antibacterial properties that merits further validation for its translation as a treatment applied to clinically-used meshes.

Citric Acid in the Passivation of Titanium Dental Implants: Corrosion Resistance and Bactericide Behavior

The passivation of titanium dental implants is performed in order to clean the surface and obtain a thin layer of protective oxide (TiO2) on the surface of the material in order to improve its behavior against corrosion and prevent the release of ions into the physiological environment. The most common chemical agent for the passivation process is hydrochloric acid (HCl), and in this work we intend to determine the capacity of citric acid as a passivating and bactericidal agent. Discs of commercially pure titanium (c.p.Ti) grade 4 were used with different treatments: control (Ctr), passivated by HCl, passivated by citric acid at 20% at different immersion times (20, 30, and 40 min) and a higher concentration of citric acid (40%) for 20 min. Physical-chemical characterization of all of the treated surfaces has been carried out by scanning electronic microscopy (SEM), confocal microscopy, and the 'Sessile Drop' technique in order to obtain information about different parameters (topography, elemental composition, roughness, wettability, and surface energy) that are relevant to understand the biological response of the material. In order to evaluate the corrosion behavior of the different treatments under physiological conditions, open circuit potential and potentiodynamic tests have been carried out. Additionally, ion release tests were realized by means of ICP-MS. The antibacterial behavior has been evaluated by performing bacterial adhesion tests, in which two strains have been used: Pseudomonas aeruginosa (Gram-) and Streptococcus sanguinis (Gram+). After the adhesion test, a bacterial viability study has been carried out ('Life and Death') and the number of colony-forming units has been calculated with SEM images. The results obtained show that the passivation with citric acid improves the hydrophilic character, corrosion resistance, and presents a bactericide character in comparison with the HCl treatment. The increasing of citric acid concentration improves the bactericide effect but decreases the corrosion resistance parameters. Ion release levels at high citric acid concentrations increase very significantly. The effect of the immersion times studied do not present an effect on the properties.

Efficacy of Er:YAG laser irradiation for decontamination and its effect on biocompatibility of different titanium surfaces

Background

Erbium yttrium–aluminum–garnet (Er:YAG) laser have been shown to be suitable for decontamination of titanium surfaces at a wide range of energy settings, however, high intensity of laser irradiation destroy titanium surface and low intensity cannot remove enough microbial biofilm. The aim of this study was to investigate the optimal energy setting of Er:YAG laser for decontamination of sandblasted/acid-etched (SLA) and hydroxyapatite (HA) titanium surfaces.

Material and methods

After supragingival biofilm construction in vivo, SLA and HA titanium discs were divided into three groups: blank control (BC, clean discs), experimental control (EC, contaminated discs) and experimental groups (EP, contaminated discs irradiated by Er:YAG laser at 40, 70, and 100 mJ/pulse). Scanning electron microscopy (SEM), live/dead bacterial fluorescent detection, and colony counting assay were used to detect the efficacy of laser decontamination. To investigate the effect of laser decontamination on titanium surface biocompatibility, MC3T3-E1 cell adhesion and proliferation activity were examined by SEM and CCK-8 assay.

Results

Er:YAG laser irradiation at 100 mJ/pulse removed 84.1% of bacteria from SLA titanium surface; laser irradiation at 70 and 100 mJ/pulse removed 76.4% and 77.85% of bacteria from HA titanium surface respectively. Laser irradiation improved MC3T3-E1 cell adhesion on both titanium surfaces. For SLA titanium discs, 100 mJ/pulse group displayed excellent cellular proliferation activity higher than that in BC group (P < 0.01). For HA titanium discs, 70 mJ/pulse group showed the highest activity comparable to BC group (P > 0.05).

Conclusions

With regards to efficient microbial biofilm decontamination and biocompatibility maintenance, Er:YAG laser at 100 mJ/pulse and 70 mJ/pulse are considered as the optimal energy settings for SLA titanium and HA titanium surface respectively. This study provides theoretical basis for the clinical application of Er:YAG laser in the treatment of peri-implantitis.

Er:YAG laser irradiation enhances bacterial and lipopolysaccharide clearance and human gingival fibroblast adhesion on titanium discs

To investigate the effect of Er:YAG laser treatment on lipopolysaccharide (LPS) clearance and fibroblast adhesion on titanium disks. Grade IV titanium discs (n = 216) were used and allocated to 6 groups. Group 1 was the negative control without Porphyromonas gingivalis inoculation. Discs in Groups 2-6 were incubated with P. gingivalis to form a biofilm. Group 3 received 0.12% chlorhexidine irrigation and Group 4 received titanium curettage to remove the biofilm. Group 5 was treated with Er:YAG laser irradiation and Group 6 was treated with titanium curettage plus Er:YAG laser irradiation. The contact angle and surface roughness were measured after the various treatments. The surface microstructure and residual bacteria were examined using scanning electron microscopy and confocal laser scanning microscopy, respectively. Residual LPS was examined using a limulus amoebocyte lysate assay and human gingival fibroblast adhesion was quantified using fluorescent microscopy. Curettage plus Er:YAG laser irradiation was the most effective method for removing bacteria and LPS. No significant difference in the amount of fibroblast adhesion was found between the control and Group 6. Combined use of Er:YAG laser irradiation and curettage optimizes LPS clearance and fibroblast adhesion on titanium discs.

Microbial profiles of peri-implant mucositis and peri-implantitis: Submucosal microbial dysbiosis correlates with disease severity

OBJECTIVE

To investigate the microbiome characteristics of peri-implant mucositis (PM) and peri-implantitis (PI), and to analyse the correlation between disease severity and submucosal microbial dysbiosis.

MATERIALS AND METHODS

A cross-sectional study design was conducted. Submucosal biofilm samples from 27 PM sites and 37 PI sites from 64 patients were collected and analysed using 16S rRNA gene sequencing (Illumina). Differences in microbiological profiles between PM and PI were evaluated using the α-diversity, β-diversity and linear discriminant analysis effect size (LEfSe) analysis. The relative abundances of the taxa at the phylum and genus levels were compared using the Wilcoxon rank test and logistic regression. The microbial dysbiosis index (MDI) was calculated, and its relationship with clinical measurements (probing depth, bleeding on probing and marginal bone loss, among others) was analysed using Pearson's correlation coefficient.

RESULTS

The overall microbiome distribution in the PM and PI sites was similar according to α- and β-diversity. Twenty-three taxa at the genus level and two taxa at the phylum level showed significant differences in relative abundance between the two clinical classifications. Five taxa at the genus level were screened out for the MDI calculation after logistic regression. No clinical measurements but marginal bone loss showed a significant positive correlation with microbial dysbiosis.

CONCLUSION

The microbiome richness, diversity and distribution were similar in PM and PI sites, including both common periodontal bacteria and novel species. In addition, an increase in marginal bone loss was significantly associated with submucosal microbial dysbiosis.

Effect of multiple sessions of photodynamic therapy on bone regeneration around dental implants among patients with peri-implantitis

OBJECTIVE

The aim of the present study was to assess the effect of multiple sessions of antimicrobial photodynamic therapy (aPDT) on bone regeneration around dental implants among patients with peri-implantitis.

METHODS

Patients with peri-implantitis were included. Therapeutically, patients were randomly divided into 4 groups: (a) Group-I: Mechanical debridement (MD) alone; (b) Group-II: MD at baseline followed by a single session of adjunct a PDT; (c) Group-III: MD at baseline followed by aPDT at baseline and at 3-months of follow-up; and Group-IV: MD at baseline followed by aPDT at baseline and at 3- and 6-months of follow-up. Demographic data was collected and peri-implant clinical (plaque index [PI], gingival index [GI], and probing depth [PD]) and radiographic (crestal bone loss [CBL]) parameters were assessed at baseline and after 9 months. Sample-size estimation was done on data from a pilot investigation and group comparisons were done using one-way analysis of variance and Bonferroni post-hoc adjustment tests. Level of significance was set at P<0.01.

RESULTS

Twenty-two, 22, 22 and 22 patients with peri-implantitis were enrolled in groups -I, -II, -III and -IV. The mean age of individuals in groups -I, -II, -III and -IV were 59.2 ± 5.3, 60.5 ± 2.8, 59.6 ± 3.1 and 58.7 ± 0.8 years, respectively. Compared with Group-I, there was a statistically significant reduction in PI (P<0.01), GI (P<0.01) and PD (P<0.01) in all groups at 9-months follow-up. There was no significant difference in PI, GI and PD in groups -II, -III and -IV at 9-months follow-up. There was no statistically significant difference in CBL in all groups at baseline and at 9-months-follow-up.

CONCLUSION

The use of aPDT as an adjunct to MD reduces the severity of peri-implant mucositis but does not contribute towards bone regeneration in peri-implant osseous defects.