Training in the use of the water jet and cold atmospheric plasma jet for the decontamination of dental implants.

OBJECTIVES: Clinical trials testing new devices require prior training on dummies to minimize the "learning curve" for patients. Dentists were trained using a novel water jet device for mechanical cleaning of dental implants and with a novel cold plasma device for surface functionalisation during a simulated open flap peri-implantitis therapy. The hypothesis was that there would be a learning curve for both devices. MATERIALS AND METHODS: 11 dentists instrumented 44 implants in a dummy-fixed jaw model. The effect of the water jet treatment was assessed as stain removal and the effect of cold plasma treatment as surface wettability. Both results were analysed using photographs. To improve treatment skills, each dentist treated four implants and checked the results immediately after the treatment as feedback. RESULTS: Water jet treatment significantly improved from the first to the second implant from 62.7% to 75.3% stain removal, with no further improvement up to the fourth implant. The wettability with cold plasma application reached immediately a high level at the first implant and was unchanged to the 4th implant (mean scores 2.7 out of 3). CONCLUSION: A moderate learning curve was found for handling of the water jet but none for handling of the cold plasma. CLINICAL RELEVANCE: Scientific rational for study: Two new devices were developed for peri-implantitis treatment (Dental water jet, cold plasma). Dentists were trained in the use of these devices prior to the trial to minimize learning effects. PRINCIPAL FINDINGS: Experienced dentists learn the handling of the water jet very rapidly and for cold plasma they do not need much training. PRACTICAL IMPLICATIONS: A clinical study is in process. When the planned clinical study will be finished, we will find out, if this dummy head exercise really minimised the learning curve for these devices.

Local Oxygen-Based Therapy (blue®m) for Treatment of Peri-Implant Disease: Clinical Case Presentation and Review of Literature about Conventional Local Adjunct Therapies.

Peri-implant diseases including peri-implant mucositis and peri-implantitis are among the major causes of failure of implant-supported dental restorations. They are characterized by progressive inflammation of the peri-implant mucosa, extending to the surrounding connective tissues and leading to bone loss and implant failure. Although strict oral hygiene practices help in preventing peri-implant diseases, plaque buildup around the implant restoration leads to chronic inflammation, due to the adherent bacterial biofilm. While mechanical debridement and non-surgical therapy to remove inflamed connective tissue (ICT) form the mainstay of treatment, additional local adjunctive therapies enhance clinical outcomes. Topical oxygen therapy is known to reduce inflammation, increase vascularity, and act as a bacteriostatic measure. The use of oxygen-based therapy (blue®m) products as a local adjunctive therapy for peri-implant mucositis and peri-implantitis can result in clinical outcomes similar to that of conventional local adjuncts such as chlorhexidine, antibiotics, and antibacterial agents. This report aims to present the clinical findings of patients with peri-implant mucositis and peri-implantitis, who were managed using local oxygen-based therapy as an adjunct to non-surgical therapy. In addition, a review of the literature about commonly used local adjuncts for peri-implant diseases has been included in the report to provide a means of comparison between conventional local adjunct therapy and topical oxygen-based therapy. Based on the reported findings and reviewed literature, local oxygen-based adjunct therapy was equally effective as conventionally used local adjuncts such as antibiotics, antibacterials, and probiotics, in treating patients with peri-implant diseases.

Photo/mechanical and physical implant surface decontamination approaches in conjunction with surgical peri-implantitis treatment: A systematic review.

AIM: To evaluate the efficacy of adjunctive/alternative photo/mechanical and physical implant-surface decontamination approaches compared to standard instrumentation in conjunction with surgical peri-implantitis treatment. MATERIALS AND METHODS: Randomized controlled clinical trials (RCTs) and controlled clinical trials investigating the efficacy of adjunctive or alternative photo/mechanical/physical measures for implant surface decontamination in conjunction with surgical peri-implantitis treatment without (PICOS 1) or with (PICOS 2) additional decontamination methods performed in test and control groups with changing inflammation parameters were covered. Changes in bleeding scores (i.e., bleeding index, or bleeding on probing [BOP]), suppuration, and probing depth (PD) were considered the primary outcomes. RESULTS: Six articles describing five original RCTs were eligible for analysis. Based on two RCTs, the adjunctive/alternative use of air polishing with glycine or erythritol powder did not improve BOP reduction compared to standard instrumentation (PICOS 1). Based on one RCT, alternative use of titanium brushes resulted in significantly higher BOP reduction compared to either air polishing or standard instrumentation (PICOS 1). During reconstructive therapy and as an adjunct to implantoplasty, use of a titanium brush did not have any benefit on the BOP and mean PD reductions compared to the control group (i.e., implantoplasty + mechanical and chemical implant surface decontamination; one RCT; PICOS 2). Use of the Er:YAG laser resulted in significantly higher PD reduction after 6 months (one RCT), whereas no difference between the test and respective controls could be detected after 1 and 2 years (one RCT). Additionally, the use of the Er:YAG laser was not associated with improved BOP reductions over respective controls (two RCTs; PICOS 2). CONCLUSIONS: Owing to the limited available data, clinical efficacy of photo/mechanical and physical implant surface decontamination in conjunction with surgical peri-implantitis therapy is inconclusive. However, titanium brushes may be beneficial in reducing signs of inflammation.

Prevention and treatment of peri-implant diseases-The EFP S3 level clinical practice guideline.

BACKGROUND: The recently published Clinical Practice Guidelines (CPGs) for the treatment of stages I-IV periodontitis provided evidence-based recommendations for treating periodontitis patients, defined according to the 2018 classification. Peri-implant diseases were also re-defined in the 2018 classification. It is well established that both peri-implant mucositis and peri-implantitis are highly prevalent. In addition, peri-implantitis is particularly challenging to manage and is accompanied by significant morbidity. AIM: To develop an S3 level CPG for the prevention and treatment of peri-implant diseases, focusing on the implementation of interdisciplinary approaches required to prevent the development of peri-implant diseases or their recurrence, and to treat/rehabilitate patients with dental implants following the development of peri-implant diseases. MATERIALS AND METHODS: This S3 level CPG was developed by the European Federation of Periodontology, following methodological guidance from the Association of Scientific Medical Societies in Germany and the Grading of Recommendations Assessment, Development and Evaluation process. A rigorous and transparent process included synthesis of relevant research in 13 specifically commissioned systematic reviews, evaluation of the quality and strength of evidence, formulation of specific recommendations, and a structured consensus process involving leading experts and a broad base of stakeholders. RESULTS: The S3 level CPG for the prevention and treatment of peri-implant diseases culminated in the recommendation for implementation of various different interventions before, during and after implant placement/loading. Prevention of peri-implant diseases should commence when dental implants are planned, surgically placed and prosthetically loaded. Once the implants are loaded and in function, a supportive peri-implant care programme should be structured, including periodical assessment of peri-implant tissue health. If peri-implant mucositis or peri-implantitis are detected, appropriate treatments for their management must be rendered. CONCLUSION: The present S3 level CPG informs clinical practice, health systems, policymakers and, indirectly, the public on the available and most effective modalities to maintain healthy peri-implant tissues, and to manage peri-implant diseases, according to the available evidence at the time of publication.

Supportive care for the prevention of disease recurrence/progression following peri-implantitis treatment: A systematic review.

OBJECTIVES: This systematic review aimed to evaluate the efficacy of supportive care provision, frequency and protocol in patients treated for peri-implantitis, as reported in prospective and retrospective studies of at least 3-years duration. MATERIALS AND METHODS: A systematic search of three electronic databases was undertaken up to 21 July 2022 and supplemented by hand-search to identify studies that included participants treated for peri-implantitis and followed for at least 3 years. Owing to high heterogeneity, a meta-analysis was not appropriate, and therefore, data and risk of bias were explored qualitatively. PRISMA guidelines for reporting were followed. RESULTS: The search identified 2596 studies. Of 270 records selected during screening, 255 were excluded through independent review and 15 studies (10 prospective and 5 retrospective, with at least 20 patients) were retained for qualitative assessments. Study designs, population characteristics, supportive care protocols and reported outcomes varied markedly. Thirteen of the 15 studies had low risk of bias. Supportive peri-implant care (SPIC) following different surgical peri-implantitis treatment protocols and with recall intervals varying between 2 months and annually resulted in peri-implant tissue stability (no disease recurrence or progression) ranging from 24.4% to 100% at patient level and from 28.3% to 100% at implant level. Sevenhundred and eighty-five patients with 790 implants were included in this review. CONCLUSIONS: Provision of SPIC following peri-implantitis therapy may prevent disease recurrence or progression. Insufficient evidence is available to identify (i) a specific supportive care protocol for secondary prevention of peri-implantitis, (ii) the effect of adjunctive local antiseptic agents in the secondary prevention of peri-implantitis and (iii) the impact of frequency of supportive care measures. Prospective, randomised, controlled studies designed to evaluate supportive care protocols are needed in future.

Primordial and primary prevention of peri-implant diseases: A systematic review and meta-analysis.

AIM: This systematic review and meta-analysis aims to assess the efficacy of risk factor control to prevent the occurrence of peri-implant diseases (PIDs) in adult patients awaiting dental implant rehabilitation (primordial prevention) or in patients with dental implants surrounded by healthy peri-implant tissues (primary prevention). MATERIALS AND METHODS: A literature search was performed without any time limit on different databases up to August 2022. Interventional and observational studies with at least 6 months of follow-up were considered. The occurrence of peri-implant mucositis and/or peri-implantitis was the primary outcome. Pooled data analyses were performed using random effect models according to the type of risk factor and outcome. RESULTS: Overall, 48 studies were selected. None assessed the efficacy of primordial preventive interventions for PIDs. Indirect evidence on the primary prevention of PID indicated that diabetic patients with dental implants and good glycaemic control have a significantly lower risk of peri-implantitis (odds ratio [OR] = 0.16; 95% confidence interval [CI]: 0.03-0.96; I2 : 0%), and lower marginal bone level (MBL) changes (OR = -0.36 mm; 95% CI: -0.65 to -0.07; I2 : 95%) compared to diabetic patients with poor glycaemic control. Patients attending supportive periodontal/peri-implant care (SPC) regularly have a lower risk of overall PIDs (OR = 0.42; 95% CI: 0.24-0.75; I2 : 57%) and peri-implantitis compared to irregular attendees. The risk of dental implant failure (OR = 3.76; 95% CI: 1.50-9.45; I2 : 0%) appears to be greater under irregular or no SPC than regular SPC. Implants sites with augmented peri-implant keratinized mucosa (PIKM) show lower peri-implant inflammation (SMD = -1.18; 95% CI: -1.85 to -0.51; I2 : 69%) and lower MBL changes (MD = -0.25; 95% CI: -0.45 to -0.05; I2 : 62%) compared to dental implants with PIKM deficiency. Studies on smoking cessation and oral hygiene behaviors were inconclusive. CONCLUSIONS: Within the limitations of available evidence, the present findings indicate that in patients with diabetes, glycaemic control should be promoted to avoid peri-implantitis development. The primary prevention of peri-implantitis should involve regular SPC. PIKM augmentation procedures, where a PIKM deficiency exists, may favour the control of peri-implant inflammation and the stability of MBL. Further studies are needed to assess the impact of smoking cessation and oral hygiene behaviours, as well as the implementation of standardized primordial and primary prevention protocols for PIDs.

Efficacy of adjunctive measures in peri-implant mucositis. A systematic review and meta-analysis.

AIM: To answer the following PICO question: In systemically healthy humans with peri-implant mucositis, what is the efficacy of patient-performed or administered (by prescription) measures used adjunctively to submarginal instrumentation, as compared to submarginal instrumentation alone or combined with a negative control, in terms of reducing bleeding on probing (BOP), in randomized controlled clinical trials (RCTs) with at least 3 months of follow-up? MATERIALS AND METHODS: Three databases were searched until April 2022. Weighted mean differences (WMDs) with 95% confidence intervals (CIs) and predictive intervals were calculated. RESULTS: Sixteen parallel RCTs corresponding to 14 studies with low/moderate risk of bias were included. Test groups showed greater reductions in BOP (%) than control groups (nstudies  = 16; npatients  = 650; WMD = 14.25%; 95% CI [9.06-19.45]; p < .001; I2  = 98.7%). The greatest WMD in BOP reductions (%) were obtained by antiseptics (ns  = 5; np  = 229; WMD = 22.72%; 95% CI [19.40-26.04]; p < 0.001; I2  = 94.8%), followed by probiotics (ns  = 6; np  = 260; WMD = 12.11%; 95% CI [3.20-21.03]; p = .008; I2  = 93.3%) and systemic antibiotics (ns  = 3; np  = 101; WMD = 5.97%; 95% CI [1.34-10.59]; p = .012; I2  = 58.1%). Disease resolution was scarcely reported (n = 6). CONCLUSIONS: Significant clinical improvements can be obtained when professional submarginal instrumentation is combined with patient-performed or administered (by prescription) adjunctive measures, although a complete disease resolution may not be achieved.

Prevention and management of peri-implant mucositis and peri-implantitis: A systematic review of outcome measures used in clinical studies in the last 10 years.

OBJECTIVES: To evaluate outcome measures, methods of assessment, and analysis in clinical studies on the prevention and management of peri-implant mucositis and peri-implantitis. METHODS: Systematic electronic searches (CENTRAL/MEDLINE/SCOPUS) up to April 2021 were conducted to identify longitudinal clinical studies with ≥10 patients on either the prevention or management of peri-implant diseases. Outcome measures of this analysis were the choice of outcome measures, methods of assessment, and analytical methods. Risk of bias was evaluated according to study design. Data were extracted into evidence tables and outcomes were analysed in a descriptive manner. RESULTS: The analysis of the 159 selected studies revealed that probing pocket depth (PPD) and bleeding/suppuration on probing (BOP) were reported in 89% and 87% of all studies, respectively. Additional outcome measures included plaque scores (reported in 64% of studies), radiographic outcomes (49%), soft tissue dimensions (34%), and composite outcomes (26%). Adverse events (8%) and patient-reported outcomes (6%) were only rarely mentioned. A primary outcome measure was clearly defined only in 36% of studies. Data on PPD, radiographic outcomes, and soft tissue dimensions were primarily reported as mean values and rarely as frequency distributions. For radiographic outcomes and soft tissue dimensions, it was frequently unclear how clustered data were handled. CONCLUSIONS: PPD and BOP were routinely reported in studies on the prevention and management of peri-implant mucositis and peri-implantitis, while composite outcomes, adverse events, and patient-reported outcomes were only infrequently described.

Prevention and management of peri-implant mucositis and peri-implantitis: A systematic review of outcome measures used in clinical studies in the last 10 years.

OBJECTIVES: To evaluate outcome measures, methods of assessment, and analysis in clinical studies on the prevention and management of peri-implant mucositis and peri-implantitis. METHODS: Systematic electronic searches (CENTRAL/MEDLINE/SCOPUS) up to April 2021 were conducted to identify longitudinal clinical studies with ≥10 patients on either the prevention or management of peri-implant diseases. Outcome measures of this analysis were the choice of outcome measures, methods of assessment, and analytical methods. Risk of bias was evaluated according to study design. Data were extracted into evidence tables and outcomes were analysed in a descriptive manner. RESULTS: The analysis of the 159 selected studies revealed that probing pocket depth (PPD) and bleeding/suppuration on probing (BOP) were reported in 89% and 87% of all studies, respectively. Additional outcome measures included plaque scores (reported in 64% of studies), radiographic outcomes (49%), soft tissue dimensions (34%), and composite outcomes (26%). Adverse events (8%) and patient-reported outcomes (6%) were only rarely mentioned. A primary outcome measure was clearly defined only in 36% of studies. Data on PPD, radiographic outcomes, and soft tissue dimensions were primarily reported as mean values and rarely as frequency distributions. For radiographic outcomes and soft tissue dimensions, it was frequently unclear how clustered data were handled. CONCLUSIONS: PPD and BOP were routinely reported in studies on the prevention and management of peri-implant mucositis and peri-implantitis, while composite outcomes, adverse events, and patient-reported outcomes were only infrequently described.

Scientific rationale for study: In 2012, recommendations on study design, key outcome measures, and reporting in clinical studies on the prevention and management of peri-implant diseases were presented. We aimed to evaluate how these recommendations were adapted and utilized in relevant studies published during the last decade. Principal findings: Recommendations on outcome measures and reporting in clinical studies on the prevention and management of peri-implant mucositis and peri-implantitis were only partially followed. Practical implications: When evaluating the evidence on the prevention and management of peri-implant diseases, the clinician should be aware of the limitations in terms of choice of outcome measures and data reporting.

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.

Effects of an amino acid buffered hypochlorite solution as an adjunctive to air-powder abrasion in open-flap surface decontamination of implants failed for peri-implantitis: an ex vivo randomized clinical trial.

OBJECTIVES: To evaluate ex vivo the efficacy of an amino acid buffered hypochlorite solution supplemented to surface debridement with air-powder abrasion in removing bacterial biofilm following open-flap decontamination of implants failed due to peri-implantitis. MATERIALS AND METHODS: This study was an ex vivo, single-blind, randomized, intra-subject investigation. Study population consisted of 20 subjects with at least three implants failed for peri-implantitis (in function for > 12 months and progressive bone loss exceeding 50%) to be explanted. For each patient, implants were randomly assigned to surface decontamination with sodium bicarbonate air-powder abrasion (test-group 1) or sodium bicarbonate air-powder abrasion supplemented by amino acid buffered hypochlorite solution (test-group 2) or untreated control group. Following open-flap surgery, untreated implants (control group) were explanted. Afterwards, test implants were decontaminated according to allocation and explanted. Microbiological analysis was expressed in colony-forming units (CFU/ml). RESULTS: A statistically significant difference in the concentrations of CFU/ml was found between implants of test-group 1 (63,018.18 ± 228,599.36) (p = 0.007) and implants of test-group 2 (260.00 ± 375.80) (p < 0.001) compared to untreated implants (control group) (86,846.15 ± 266,689.44). The concentration of CFU/ml on implant surfaces was lower in test-group 2 than in test-group 1, with a statistically significant difference (p < 0.001). CONCLUSION: The additional application of amino acid buffered hypochlorite solution seemed to improve the effectiveness of implant surface decontamination with air-powder abrasion following open-flap surgery. CLINICAL RELEVANCE: Lacking evidence on the most effective method for biofilm removal from contaminated implant surfaces, the present experimental study provides further information for clinicians and researchers.

Identification of Senescent Cells in Peri-Implantitis and Prevention of Mini-Implant Loss Using Senolytics.

Peri-implantitis is a disease that causes the detachment of orthodontic mini-implants. Recently, stress-induced senescent cells have been reported to be involved in various inflammatory diseases. Senescent cell-eliminating drugs, termed "senolytics", can improve the symptoms of such diseases. However, the relationship between peri-implantitis and senescent cells remains unclear. In this study, we evaluated the presence of senescent cells in a rat peri-implantitis model developed with a gum ring. The effect on bone resorption and implant loss was also investigated with and without senolytics (Dasatinib and Quercetin). The number of senescence markers (p19, p21, and p16) was found to increase, and implant detachment occurred in 24 days. After the administration of senolytics, the number of senescence markers decreased and implant detachment was inhibited. This study suggests that senescent cells aggravate peri-implantitis and senolytic administration latently reduces implant loss by inhibiting senescence-related mechanisms.

Critical review on quality of methodology and recommendations of clinical practice guidelines for peri-implantitis.

BACKGROUND: Peri-implantitis is of high prevalence with the popularity of dental implants nowadays. Guidelines or consensus have been developed in succession, and we are little-known about their quality. The objective of this study is to evaluate the methodological quality of these guidelines and analyze the consistency of the clinical recommendations. METHODS: We searched for guidelines or consensus on prevention, diagnosis, and/or treatment of peri-implantitis through PubMed, Web of Science, Cochrane Library until January 15th, 2022. In addition, we also searched the websites of the American Dental Association, International Team for Implantology, FDI World Dental Federation, and some guideline collection databases. Appraisal of Guidelines for Research & Evaluation II methodological quality instrument was used to assess the selected guidelines. Furthermore, we described the consistency of recommendations across the included guidelines. RESULTS: In total, 15 guidelines were included. The mean values of the six domains score all below 50%. The mean scores of Applicability were lowest (mean:15%, range:4-29%). As to the overall quality, eleven (73%) were recommended after being modified, and four (27%) were not recommended. Among the clinical recommendations, 53 (67.09%) are for treatment of peri-implantitis, 13 (16.46%) for monitoring issue, 7 (8.86%) for diagnosis, 3 (3.80%) for the disease prevention. CONCLUSIONS: Improving methodology quality and strengthening clinical evidence is essential in the future guideline development in a range of disciplines for improving the treatment effectiveness of people with peri-implantitis. And there is a lack of integrated guidelines in the case of the COVID-19 pandemic.

Common practices of dental implants maintenance among dental hygiene professionals in Israel and Germany.

OBJECTIVE: The aim of this study was to assess the common practices of dental implant maintenance among dental hygiene professionals (DHP) in Israel (IL) and Germany (GE). METHODS: An online questionnaire was developed by the Periodontology Departments of Tel Aviv (IL) and Frankfurt University (GE) to address demographics, training, prevention and treatment of peri-implant diseases. The questionnaire was distributed by DHP associations via social media. RESULTS: The responses of 376 DHPs (IL: 169; GE: 207) were analysed. Most participants were female (IL: 168/99%; GE: 203/98%), had received education (IL: 179/97%; GE: 207/97%) and were working in their home countries (IL: 182/99%; GE: 211/99%). Peri-implant probing was not performed by 22% of DHPs in IL and 5% in GE. Of the DHPs who used probes, 49% used metal probes in IL, while 40% used plastic probes in GE (p < 0.001). A majority of DHPs performed peri-implant instrumentation (IL: 168/99%; GE: 190/92%). Most DHPs from IL did not use devices other than hand and/or sonic/ultrasonic instruments for peri-implant cleaning (IL: 130/77%; GE 5/2%); in GE, the use of airflow (IL: 31/18%; GE: 199/96%) is popular (p < 0.001). CONCLUSIONS: Most DHPs in IL and GE perform peri-implant probing and debridement. However, there are some distinct differences between the two countries regarding the choice of instruments and treatment regimens.

It is all about peri-implant tissue health.

Healthy peri-implant tissues have become synonymous with implant success and a major challenge in contemporary implant dentistry. Numerous local and systemic factors, as well as iatrogenic and other hitherto underappreciated factors of potential clinical relevance may influence the outcome of implant therapy. In this volume of Periodontology 2000, a group of outstanding experts has elaborated on the latest insights on the prevention and management of major surgical, biological and technical complications, to facilitate the establishment and maintenance of peri-implant health. This volume focusses on factors affecting early and late implant loss and the potential role of systemic diseases and local conditions. It comprehensively discusses the implementation of guided implant surgery to facilitate the cleansibility of implant-supported restorations, as well as iatrogenic factors related to bone augmentation/sinus grafting procedures. The challenges associated with soft-tissue grafting and the prevention of esthetic complications are also reviewed as the paradigm of success in implant dentistry shifts from implant survival towards a greater focus on patient-reported outcomes. Prosthetic failures remain a significant challenge and are discussed in light of new evidence, as is the relevance of the structural dimensions of the peri-implant mucosa. The volume closes with detailed and well-illustrated appraisals of the surgical management of peri-implantitis, the management and sequelae of dental implant removal, and the latest evidence for the oral health related quality of life in patients treated with dental implants.

Isoeugenol-functionalized nanogels inhibit peri-implantitis associated bacteria in vitro.

OBJECTIVES: Obligate and facultative anaerobic bacteria adhering to dental implants are a major cause for peri-implant inflammation, which, if left untreated, can lead to implant loss. Previously, our group developed a new route for the synthesis of isoeugenol-functionalized aqueous nanogels for implant coatings. METHODS: Here, the antimicrobial activity of several new nanogels differing in spacer length (n = 6, 9, 44), radius (60-200 nm), and amount of isoeugenol functional substance (1-20 mol%) was tested against the following peri-implantitis-associated species: Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Aggregatibacter actinomycetemcomitans, Escherichia coli, Actinomyces viscosus, Enterococcus faecalis, Staphylococcus aureus, Streptococcus oralis, S. parasanguinis, and the yeast Candida albicans. The minimal bactericidal concentration (MBC) and fungicidal concentration (MFC) were determined for each combination. In addition, transmission electron microscopy (TEM) and fluorescence microscopy after live-dead-staining (LD-S) were performed to visualize nanogel-microbe interactions. RESULTS: Two nanogels, NG9-3 and NG9-4 (colloids of 80-150 nm, with a spacer length of n = 9 and feeding between 5 and 10 mol% isoeugenol), had an inhibitory effect on all Gram-positive species and on P. gingivalis and P. intermedia with MBC ≥31.25 µg/ml. TEM and LD-S images showed that cellular adhesion and uptake of nanogels resulted in swelling, shedding, or even complete detachment of the cell wall and then to bursting (see graphical abstract). CONCLUSIONS: Functional nanogels can be used as building blocks in the design of bioactive coatings on implants to prevent infection and accelerate tissue regeneration, but the concentrations required are higher than for antibiotics.

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.

Overview of Antibacterial Strategies of Dental Implant Materials for the Prevention of Peri-Implantitis.

As dental implants have become one of the main treatment options for patients with tooth loss, the number of patients with peri-implant diseases has increased. Similar to periodontal diseases, peri-implant diseases have been associated with dental plaque formation on implants. Unconventional approaches have been reported to remove plaque from infected implants, but none of these methods can completely and permanently solve the problem of bacterial invasion. Fortunately, the constant development of antibacterial implant materials is a promising solution to this situation. In this review, the development and study of different antibacterial strategies for dental implant materials for the prevention of peri-implantitis are summarized. We hope that by highlighting the advantages and limitations of these antimicrobial strategies, we can assist in the continued development of oral implant materials.

Comparison of irrigation protocols for the internal decontamination of dental implants-results of in vitro and in vivo studies.

OBJECTIVES: Previous investigations have shown a progressive bacterial colonization of the internal cavities of two-piece dental implants with possible implications for peri-implant bone loss. The aim of the study was to compare different irrigation protocols for the internal decontamination of implants in vitro and in vivo. MATERIALS AND METHODS: In the in vitro part, 80 samples were obtained 24 h after inoculation with an aliquot of subgingival bacteria from 40 implants as follows: before and after either cleaning with a brush and an irrigation solution (irrigation-brush-irrigation: test) or repeated irrigation alone (irrigation-irrigation: control). In the clinical study, 40 samples from twenty partially edentulous patients contributing each with one implant were collected after removal of abutment and suprastructure with sterile paper points immediately before and after decontamination and subsequently analyzed for total bacterial counts (TBC) by real-time-PCR. Irrigation solutions were chlorhexidine (0.2% (CHX)), H2 O2 (10%), alcohol (70%, (ALC)), and NaCl (0.9%). Differences in proportional reduction of TBC between the four irrigation solutions were analyzed. RESULTS: Irrigation with H2 O2 showed the highest effect in both parts of the study (relative TBC reduction in vitro: H2 O2 : 87.1%, CHX: 56.9%, ALC: 43.7%, NaCl: 42.7%; in vivo: H2 O2 : 51.4%, ALC: 30.4%, NaCl: 26.3%, CHX: 7.1%). The additional use of a brush showed no beneficial effect (p = 0.088). Overall, H2 O2 was superior to all other irrigation solutions with regard to relative TBC reduction. CONCLUSIONS: The present results indicate the potential of an irrigation protocol that includes a 10% H2 O2 solution for the internal decontamination of implants. (ClinicalTrials.gov NCT01917305).

Hygiene Recall in Diabetic and Nondiabetic Patients: A Periodic Prognostic Factor in the Protection Against Peri-Implantitis?

PURPOSE: Diabetes mellitus is associated with an increased risk of poor outcomes with dental implant placement. This study aims to identify if frequency of hygiene visits is a protective factor for the development of peri-implantitis in diabetic patients. METHODS: A retrospective cohort design was conducted on patients presenting for dental implant placement at the Philadelphia Veterans Affairs (VA) Medical Center from 2006 to 2012. The primary predictor variable was hygiene frequency, recorded as either infrequent, annual (7-12 month recall), or biannual (≤6-month recall). The number of months between implant placement and the presence of peri-implantitis was the primary outcome (time-to-peri-implantitis) variable, which was assessed on a subject level and adjusted for clustered, correlated multiple implants on the same subject. Additional variables were greater than or equal to 60 years of age, male gender, smokers, short implant length, diabetes, uncontrolled diabetes, and removable prostheses. Descriptive, univariate, and Cox proportional hazards regression statistics were computed to measure associations with peri-implantitis with P ≤ .05 used to define statistical significance. RESULTS: The study sample was composed of 286 patients. In total, 748 implants were placed. Subjects greater than or equal to 60 years of age were 2 times more likely to develop peri-implantitis (hazards ratio (HR) = 2.015, 95% Cl (0.985-4.119), P = .0549). Subjects receiving implant-supported removable prostheses were 2.3 times more likely to develop peri-implantitis (HR = 2.315, 95% CI (1.006-5.327), P = .0485). With each hygiene visit, patients' risk of developing peri-implantitis decreased 20% (HR = 0.805, 95% Cl (0.394-1.647), P = .5528). In addition, diabetic patients were 49% more likely to develop peri-implantitis (HR = 1.491, 95% CI (0.758-2.936), P = .2475) than nondiabetic patients. CONCLUSIONS: Diabetic patients may be at increased risk for the development of peri-implantitis and an increased frequency of hygiene visits may reduce peri-implant diseases.