In-vitro polymicrobial oral biofilm model represents clinical microbial profile and disease progression during implant-related infections.

AIM: Clinically relevant in-vitro biofilm models are essential and valuable tools for mechanistically dissecting the etiopathogenesis of infectious diseases and test new antimicrobial therapies. Thus, the aim of this study was to develop and test a clinically relevant in-vitro oral polymicrobial biofilm model that mimics implant-related infections in terms of microbial profile. METHODS AND RESULTS: For this purpose, 24-well plate system was used to model oral biofilms, using three different microbial inoculums to grow in-vitro biofilms: (1) human saliva from periodontally healthy patients; (2) saliva as in inoculum 1 + Porphyromonas gingivalis strain; and (3) supra and subgingival biofilm collected from peri-implant sites of patients diagnosed with peri-implantitis. Biofilms were grown to represent the dynamic transition from an aerobic to anaerobic community profile. Subsequently, biofilms were collected after each phase and evaluated for microbiological composition, microbial counts, biofilm biomass, structure, and susceptibility to chlorhexidine (CHX). Results showed higher live cell count (P < .05) for biofilms developed from patients' biofilm inoculum, but biomass volume, dry weight, and microbiological composition were similar among groups (P > .05). Interestingly, according to the checkerboard DNA-DNA hybridization results, the biofilm developed from stimulated human saliva exhibited a microbial composition more similar to the clinical subgingival biofilm of patients with peri-implantitis, with proportions of the main pathogens closer to those found in the disease. In addition, biofilm developed using saliva as inoculum was shown to be susceptible to CHX with significant reduction in bacteria compared with biofilms without exposure to CHX (P < .05). CONCLUSION: The findings suggested that the in-vitro polymicrobial biofilm developed from human saliva as inoculum is a suitable model and clinically relevant tool for mimicking the microbial composition of implant-related infections.

Clinical efficacy of triclosan-containing toothpaste in peri-implant health: A systematic review and meta-analysis of randomized clinical trials.

STATEMENT OF PROBLEM: Recent evidence suggests that toothpaste containing 0.3% triclosan (TCS) is more effective than regular toothpaste in improving clinical periodontal conditions. However, a consensus on whether TCS favors a healthy peri-implant environment is limited. PURPOSE: The purpose of this systematic review and meta-analysis of randomized clinical trials was to determine the effects of TCS-containing toothpaste on dental implant health based on clinical, immunological, and microbiological parameters, as well as on reported adverse events. MATERIAL AND METHODS: Clinical studies comparing peri-implant conditions in participants by using TCS toothpaste versus conventional fluoride toothpaste (control) were extracted from 9 databases. The studies were assessed with the Cochrane risk-of-bias tool for randomized clinical trials (RoB 2). Datasets for bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL), gingival index (GI), plaque index (PI), osteo-immunoinflammatory mediators, and bacterial load were plotted, and the standard mean difference (SMD) quantitative analysis was applied by using the Rev Man 5.3 software program. Adverse effects reported by the studies were also tabulated. The certainty of evidence was assessed by using the grading of recommendations assessment, development, and evaluation approach. RESULTS: Six studies were included in the meta-analyses. BOP was higher in the control group than in the TCS toothpaste group at 3 months (SMD -0.59 [-1.11, -.07] P=.002, I2=77%) and 6 months (SMD -0.59 [-0.83, -0.34] P=.009, I2=79%). PD (SMD -0.04 [-0.08, -0.00] P=.04, I2=0%) was also deeper in the control group versus TCS toothpaste at 6 months (SMD -0.41 [-0.73, -0.10] P=.04, I2=77%). CAL, GI, and PI did not differ between groups (P>.05). Among the osteo-immunoinflammatory mediators, IL-10 levels increased, and IL-1ß and osteoprotegerin levels decreased in the TCS toothpaste group (P<.05). Microbiological findings found that TCS toothpaste prevented the growth of periodontal pathogens, specifically in up to approximately 20% of the Prevotella intermedia. Adverse effects were not reported after toothbrushing in either group. However, most studies had "some" or "high" risk of bias, and the certainty of the evidence was considered to be "very low." CONCLUSIONS: Most studies were short-term (3 and 6 months) analyses, and the results found that, although TCS-containing toothpaste had positive osteo-immunoinflammatory and microbiologic results, clinical parameters, including CAL, GI, and PI, were not influenced.

Unpredictable Electrochemical Processes in Ti Dental Implants: The Role of Ti Ions and Inflammatory Products.

Peri-implantitis is a substantially prevailing condition. A potential risk factor for peri-implantitis is Ti implant corrosion. During inflammation, substantial quantities of reactive oxygen species (ROS) secretion and local acidification occur. Little is known about the interaction between the inflammatory and corrosion products on Ti surface corrosion. Therefore, the objective of the current study was to evaluate the synergistic effect of hydrogen peroxide (H2O2), lactic acid, and Ti ions on Ti corrosion. Twenty-seven commercially pure Ti samples were polished (Ra ≈ 45 nm) and divided into 9 groups as a function of electrolyte: (1) artificial saliva (AS) as control (C), (2) AS + Ti ions 20 ppm (Ti), (3) AS + lactic acid (pH = 5.5) (L), (4) AS + lactic acid + Ti ions 20 ppm (TiL), (5) AS + H2O2 0.5 mM (HP0.5), (6) AS + H2O2 1.0 mM (HP1.0), (7) AS + H2O2 0.5 mM + Ti ions 20 ppm (HP0.5Ti), (8) AS + H2O2 0.5 mM + lactic acid (HP0.5L), and (9) AS + H2O2 0.5 mM + Ti ions 20 ppm + lactic acid (HP0.5TiL). Electrochemical tests were performed following ASMT guidelines. Based on Tafel's method, current density (icorr) and corresponding potential (Ecorr) were acquired from potentiodynamic curves. Using electrochemical intensity spectroscopy (EIS), Nyquist and Bode plots were derived. Using a modified Randles circuit, charge transfer resistance (Rct) and capacitance (Cdl) were estimated. Based on open-circuit potential data, groups C and Ti had the lowest potentials (around -0.3 and -0.4 V vs SCE, respectively), indicating a lower passivation tendency compared to the other groups. From potentiodynamic curves, groups HP0.5 and HP1.0 increased icorr the most. From EIS data, groups HP0.5 and HP1.0 demonstrated the lowest impedance and phase angle on the Bode plot, indicating the highest corrosion kinetics. Based on EIS modeling, the combination of Ti ions, lactic acid, and H2O2 (group HP0.5TiL) significantly decreased Rct (p < 0.05). In conclusion, the concurrent presence of Ti ions, lactic acid, and H2O2 in the vicinity of the Ti surface increased the corrosion kinetics. High corrosion may produce more Ti products in the peri-implant tissues, which may increase the potential risk of peri-implantitis.

Application of polyetheretherketone (PEEK) posts: evaluation of fracture resistance and stress distribution in the root: in vitro and finite element analyses.

To evaluate the feasibility of using a milled polyetheretherketone (PEEK) post and core in endodontically treated teeth with or without a ferrule. Sixty bovine tooth roots were endodontically treated followed by cementation of intraradicular retainers (IR), according to each experimental group: a) non-ferrule glass fiber post (f0FP); b) 2-mm-ferrule glass fiber post (f2FP); c) non-ferrule resized glass fiber post (f0PR); d) 2-mm-ferrule resized glass fiber post (f2PR); e) non-ferrule PEEK post and core (f0PPC); and f) 2-mm-ferrule PEEK post and core (f2PPC). Metal crowns were made and cemented. A periodontal ligament was simulated using polyether. A force was applied to the palatine portion of each sample at 45°, until fracture. Fracture resistance data were submitted to two-way ANOVA and Tukey's test (α = 0.05). Three-dimensional digital models were developed to calculate the tensions formed in the root using finite element analysis. Models of glass fiber posts and PEEK posts and cores were evaluated with or without a ferrule. The results were analyzed by the Mohr-Coulomb criterion. The type of IR was not influenced by fracture strength (p = 0.243). There were significant statistical differences among the remaining factors. Ferrule groups had greater fracture resistance, and the failure mode of teeth with a ferrule was more catastrophic than the non-ferrule group. A ferrule increases fracture resistance and influences failure mode; the PEEK post and core did not modify the biomechanics of endodontically treated teeth, and resembled the glass fiber post results. The crack initiation point differed between the ferrule and non-ferrule groups.

Funding assistance and global productivity in the field of implant overdentures: A bibliometric analysis of 35 years.

STATEMENT OF PROBLEM: Implant overdentures have been widely used as a treatment option for edentulous patients. However, the development of implants, aside from commercial growth, requires funding assistance to determine scientific reliability and clinical applications. Nonetheless, bibliometric studies in the implant overdenture field are lacking. PURPOSE: The purpose of this bibliometric analysis was to evaluate the prevalence of funding and its bibliometric associated parameters according to the financial assistance granted and the implant overdenture documentation over time. MATERIAL AND METHODS: Six databases were assessed, and 12 bibliometric parameters related to the economy, geographical origin, publication details, and corresponding author metrics were recorded. An incidence rate ratio was applied by using a multiple Poisson regression model (α=.05) to assess the association between funding and each bibliometric parameter. RESULTS: In total, 1369 studies published between 1986 and 2021 were assessed bibliometrically. The prevalence of funded studies was 34.8% (n=477). The parameter associated with the presence of funding was country income (P<.01), with those having a high and upper-middle income being more funded than those with a lower-middle and low income. Oceania and South America were the continents more frequently funded (P<.05), with Africa being the least frequent. Randomized and nonrandomized controlled trials, in vitro studies, and in silico studies were more funded (P<.001) than case reports and series. Stud and ball attachment systems were more funded (P<.01) than studies with more than 1 retention system. Funding increased over time (P<.01), and corresponding authors with a higher h-index had more studies funded (P<.05). CONCLUSIONS: The number of funded studies on implant overdentures increased over the years. Other bibliometric parameters such as country income, continent, study design, retention system, and corresponding author h-index were associated with the frequency of funded studies published.

Factors and clinical outcomes for standard and mini-implants retaining mandibular overdentures: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: Standard-diameter dental implants are not always applicable because of anatomic limitations of the residual ridge. Thus, mini-implants have been increasingly used and offer an alternative. However, data regarding prosthetic complications, maintenance factors, and clinical outcomes are limited. PURPOSE: The purpose of this systematic review and meta-analysis was to compare prosthetic complications and maintenance events and clinical outcomes in residual ridges rehabilitated with mandibular implant overdentures (IODs) by using standard implants or mini-implants. MATERIAL AND METHODS: Nine electronic databases were searched. Quantitative analyses to measure the risk ratio (RR) and standardized mean difference (SMD) were applied. Those methods were used to assess prosthetic complications and maintenance events (abutment adjustments, replacement of retentive element, occlusal adjustment, and overdenture fracture) and clinical outcomes related to postoperative pain, probing depth (PD), plaque index (PI), marginal bone loss (MBL), and implant survival rate. RESULTS: Altogether, 7 publications were selected. Mini-implants presented reduced abutment adjustments (RR 0.23 [0.07, 0.73], P=.01), replacement of retentive element (RR 0.41 [0.31, 0.54], P<.001), occlusal adjustment (RR 0.53 [0.31, 0.91], P=.02), and overdenture fracture (RR 0.46 [0.23, 0.94], P=.03) compared with standard implants. Additionally, mini-implants presented lower values for PI at 6 months (SMD -0.27 [-0.47, -0.08], P=.006) and 12 months (SMD -0.25 [-0.46, -0.05], P=.01). No additional tangible differences were noted. CONCLUSIONS: Mini-implants might be an alternative choice based on the number of prosthetic complications and maintenance events. This was also confirmed by the comparable clinical data between standard implants and mini-implants.

Antimicrobial behavior of titanium coating with chlorhexidine-doped thin film exposed to a biofilm supplemented with nicotine.

Because nicotine upregulates the growth of most oral bacteria, this in vitro study investigated the antimicrobial effect of chlorhexidine-doped thin film on commercially pure titanium against Fusobacterium nucleatum (F. nucleatum) biofilm supplemented with different concentrations of nicotine (0, 1, and 2 mg/mL). Biofilms were formed on a chlorhexidine-doped thin film on commercially-pure-titanium discs and compared to the control groups. Biofilm viability, total biofilm growth using a spectrophotometer, extracellular polysaccharide content, and pH variations were assessed as dependent variables. Data were submitted to ANOVA and Tukey honest significant difference tests (α=0.05). F. nucleatum biofilm growth was inhibited when exposed to chlorhexidine-doped thin film (p<0.05). Biofilm supplemented with nicotine did not impact the synthesis of EPS on the same type of treatment (p>0.05). The pH values were significantly increased with the increase of nicotine concentration (p<0.05). Chlorhexidine-doped thin film was effective in reducing F. nucleatum biofilm supplemented with nicotine.

Microbiological effects of amoxicillin plus metronidazole in the treatment of young patients with Stages III and IV periodontitis: A secondary analysis from a 1-year double-blinded placebo-controlled randomized clinical trial.

BACKGROUND: Despite the body of evidence supporting the clinical benefits of metronidazole (MTZ) and amoxicillin (AMX) in the treatment of young patients with periodontitis, the microbiological outcomes of this antibiotic protocol have been less explored. This study evaluated the microbiological effects of adjunctive MTZ+AMX in the treatment of young patients with periodontitis. METHODS: Subjects with periodontitis Stages III or IV and ≤30 years old were randomly allocated to receive scaling and root planing (SRP) with placebo (n = 15) or with MTZ (400 mg) and AMX (500 mg) three times a day for 14 days (n = 15). Nine subgingival biofilm samples per subject (three samples from each probing depth (PD) category: ≤3, 4-6, and ≥7 mm) were collected at baseline and 3-, 6-, and 12-months post-treatment and individually analyzed for 40 bacterial species by checkerboard DNA-DNA hybridization. RESULTS: Thirty subjects (15/group) with mean ages 27.6 ± 3.5 (control) and 26.8 ± 3.9 (test) were included. At 12 months post-therapy, the antibiotic group harbored lower proportions of red complex (1.3%) than the placebo group (12.5%) (p < 0.05). SRP + MTZ+AMX was more effective than mechanical treatment in reducing levels/proportions of several pathogens and increasing proportions of Actinomyces species (p < 0.05). Levels/proportions of Aggregatibacter actinomycetemcomitans were only reduced in the antibiotic group (p < 0.05). This group also exhibited greater reduction in the number of sites with PD ≥5 mm and higher percentage of subjects reaching the clinical end point for treatment (≤4 sites with PD ≥5 mm) than the control group (p < 0.05). CONCLUSION: SRP+MTZ+AMX allowed for establishing a long-term healthier subgingival biofilm community and periodontal clinical condition, than SRP only.

Translating the determinant aspects on the study design in the dental implant field.

Objective: In this article, we analyzed the important categories capable of interfering with the determinants of scientific advancement in the type of study, considering seven leading journals over a 20-year. Methodology: A bibliometric review was performed at the website of well-established implant dentistry journals in five-time points defined to represent a 20-year period of observation. The measures associated with the type of study design were: the country of origin of the article, country income, continent of the corresponding author, inter-institutional collaboration, interdisciplinary collaboration, type of funding, and topic of research. Logistic regression was used in the multiple models to identify the exploratory factors associated with the type of study. Results: From a total of 1,944 articles, 50.6% comprised clinical studies. High-income countries and continents stood out for developing more clinical research than others. Since research funders request more collaborative research, overall clinical studies depended upon more inter-institutional collaboration than the others. Most clinical studies were partly supported by research institutes or universities and by industry. About the research topic, the majority of the clinical and animal studies disclosed surgical procedures. Conclusions: High-income countries and continents are more likely to develop clinical studies in the surgical procedures field. The highest collaborations in terms of the number of institutions and funding sources are more prevalent in clinical research designs. Indeed, most in vivo studies in dental implant fields are performed to evaluate new materials or even new surgical procedures.

Nicotine is a potent extracellular polysaccharide inducer in Fusobacterium nucleatum biofilms

The purpose of this in vitro study was to analyze the influence of nicotine on the extracellular polysaccharides in Fusobacterium nucleatum biofilm. Methods: F. nucleatum (ATCC 10953) biofilms supplemented with different concentrations of nicotine (0, 0.5, 1, 2, 4, and 8 mg/mL) were grown in two different BHI broth conditions [no sucrose and 1% sucrose]. Extracellular polysaccharides assay, pH measurements, and a spectrophotometric assay were performed. Data were submitted for ANOVA and Tukey honestly significant difference analyses (HSD) tests (α =.05). Results: Extracellular polysaccharides synthesis was influenced by an interaction between nicotine concentrations and growth medium solution containing sucrose (P<.05). The pH values declined in the sucrose-exposed biofilm were greater than in the group exposed only to nicotine (P<.05). The biofilm exposed to sucrose and nicotine had a higher total biofilm growth (P<.05) than the nicotine-treated biofilm without sucrose. Conclusions: Regardless of sucrose exposure, biofilms exposed to different nicotine concentrations influenced the amount of extracellular polysaccharides

Application of polyetheretherketone (PEEK) posts: evaluation of fracture resistance and stress distribution in the root: in vitro and finite element analyses

Abstract To evaluate the feasibility of using a milled polyetheretherketone (PEEK) post and core in endodontically treated teeth with or without a ferrule. Sixty bovine tooth roots were endodontically treated followed by cementation of intraradicular retainers (IR), according to each experimental group: a) non-ferrule glass fiber post (f0FP); b) 2-mm-ferrule glass fiber post (f2FP); c) non-ferrule resized glass fiber post (f0PR); d) 2-mm-ferrule resized glass fiber post (f2PR); e) non-ferrule PEEK post and core (f0PPC); and f) 2-mm-ferrule PEEK post and core (f2PPC). Metal crowns were made and cemented. A periodontal ligament was simulated using polyether. A force was applied to the palatine portion of each sample at 45°, until fracture. Fracture resistance data were submitted to two-way ANOVA and Tukey's test (α = 0.05). Three-dimensional digital models were developed to calculate the tensions formed in the root using finite element analysis. Models of glass fiber posts and PEEK posts and cores were evaluated with or without a ferrule. The results were analyzed by the Mohr-Coulomb criterion. The type of IR was not influenced by fracture strength (p = 0.243). There were significant statistical differences among the remaining factors. Ferrule groups had greater fracture resistance, and the failure mode of teeth with a ferrule was more catastrophic than the non-ferrule group. A ferrule increases fracture resistance and influences failure mode; the PEEK post and core did not modify the biomechanics of endodontically treated teeth, and resembled the glass fiber post results. The crack initiation point differed between the ferrule and non-ferrule groups.

Impact of CAD-CAM materials and bonding protocol on the bond strength between denture base/artificial teeth: a systematic review and meta-analysis.

PURPOSE: To identify the most effective bonding protocol between the denture base and artificial teeth made with different CAD/CAM materials (milled and 3D printed) compared to conventional heat-cured materials. MATERIALS AND METHODS: This review was performed according to the Preferred Reporting Items for Systematic and Meta-Analysis (PRISMA) criteria and registered in PROSPERO (CRD42021276084). An electronic search was performed independently by two examiners in the MEDLINE/PubMed, Cochrane Library, Scopus, Web of Science, ProQuest, and OpenGrey databases for articles published up to and including December 2021. RESULTS: The electronic search returned 806 articles, and after duplicates were removed, the total was 589 articles. Four articles were selected according to the eligibility criteria. Evaluating the different combinations of denture base materials and artificial teeth, the IvoBase CAD Bond (Ivoclar Vivadent) was effective for bonding the CAD/CAM denture bases to prefabricated acrylic resin denture artificial teeth. There were no differences compared to heat-cured denture base bonding to prefabricated acrylic resin denture artificial teeth (χ2: 68.56; I2: 96%; P < .001). CONCLUSION: IvoBase CAD Bond as a bonding system can be an alternative for using new technologies in the fabrication of α CAD/CAM base with prefabricated acrylic resin denture artificial teeth.

Bibliometric assessment in implant-retained overdenture articles: Mapping citation and journal impact factor trends.

STATEMENT OF PROBLEM: Implant-retained overdentures are a recognized treatment option. However, a comprehensive assessment of all articles on implant-retained overdentures to identify publication standards such as mean citation and the Journal Citation Reports (JCR) impact factor is lacking. PURPOSE: The purpose of this bibliometric assessment was to evaluate the association of mean citation and JCR impact factor with bibliometric parameters in articles on implant-retained overdentures. MATERIAL AND METHODS: Articles reporting randomized controlled clinical trials (RCTs) and nonrandomized controlled clinical trials (N-RCTs); case reports and series; retrospective studies; and in silico, in vitro, or systematic reviews in 6 databases were included. Data were extracted, and 2 multiple Poisson regressions analyses were applied (α=.05). The dependent variables were mean citation and JCR impact factor, which were evaluated to identify their association with bibliometric parameters by using prevalence ratio (PR) values. RESULTS: A total of 1369 articles published from 1986 to 2021 were included. The data revealed a high mean citation and high JCR impact factor for RCT, N-RCT, retrospective, and in vitro studies (P<.05). In silico studies presented a high mean citation (P<.001). Senior researchers with a high h-index were more likely to have a high mean citation and publications with a high JCR impact factor (P<.001). Also, senior authors associated with an international network were more likely to have a high mean citation (P=.001). High-income countries had more studies with a high mean citation and JCR impact factor (P<.05). Higher JCR impact factors were associated with articles evaluating only the maxilla or mandible (P<.05). The topics "implant setting" and "macrodesign" were associated with a high mean citation (P<.05). CONCLUSIONS: The publication trends suggest a high mean citation and a high JCR impact factor for clinical designs (RCT, N-RCT, retrospective) and in vitro studies. The same pattern was also displayed for researchers with a high h-index and located in high-income countries.

Oral Microorganisms and Biofilms: New Insights to Defeat the Main Etiologic Factor of Oral Diseases.

The oral cavity presents a highly diverse community of microorganisms due to the unique environmental conditions for microbial adhesion and growth [...].

Effect of glaze and chlorhexidine on physical and mechanical properties of bis-acryl resin: An in situ study.

BACKGROUND: Temporary prosthesis protects the oral tissues, in addition to providing aesthetic look and masticatory function until a definitive prosthesis is manufactured. OBJECTIVES: To evaluate the effect of glaze and 0.12% chlorhexidine (CHX) on the physical and mechanical properties of bis-acryl, and to evaluate the antimicrobial efficacy of CHX. MATERIAL AND METHODS: Eighty specimens of bis-acryl resin were made. Over 40 of them the glaze was applied. One specimen with and 1 specimen without glaze were placed in niches of an appliance manufactured for each patient. Each of the 20 volunteers received 2 devices. Initially, the volunteers used one device and treated it with sucrose for 7 days (control), and later they used the other device and treated it with sucrose and CHX for 7 days (test). Color, microhardness, roughness, surface energy, and insoluble extracellular polysaccharides (EPS) tests were performed. All results were submitted to the Tukey's test, with the exception of the EPS results, which were submitted to the Student's t test. RESULTS: The ΔE00 of the unglazed control group was significantly higher than that of the unglazed test group. In all groups, a significant decrease in microhardness occurred over time. At both times, the glaze significantly increased the microhardness of the specimens (in all the glazed groups). At the final time, the test glaze group showed significantly higher microhardness compared with the control glaze group. Roughness in the groups without glaze increased significantly with CHX treatment over time. At both times, the glaze generated a significant reduction in roughness in the control and test groups. There was a significant reduction in surface energy over time in all groups. In most comparisons, the glazed groups showed significantly higher surface energy values compared with the unglazed control group. At the final time point, the unglazed test group showed a significantly higher surface energy value than the unglazed control group; and the glazed test group showed a significantly higher surface energy value compared with the glazed control group. The resins that received CHX had a significantly lower amount of biofilm. CONCLUSIONS: Color values were clinically acceptable in all tested groups. At both time points, the roughness values were clinically acceptable only in the glazed groups. Glaze increased the microhardness of the specimens. Microhardness and surface energy were reduced over time in all groups. Chlorhexidine can help prevent microhardness degradation. Glaze and CHX can increase surface energy. Chlorhexidine reduced the amount of bacterial biofilm.

Mapping the trends and impact of research collaboration between countries in oral implantology publications: A bibliometric analysis from 1999 to 2019.

STATEMENT OF PROBLEM: Scientific collaboration provides a suitable strategy for enhancing the exchange of knowledge and technological development. However, the impact of collaboration in oral implantology research between countries and how it has been influenced by the income status of the country has not been previously evaluated. PURPOSE: The purpose of this bibliometric analysis was to evaluate how collaboration between countries affected oral implant publications and whether patterns of collaboration differ depending on the country's income. MATERIAL AND METHODS: Articles were retrieved from 7 well-established journals whose scope included oral implantology at 5 time points (1999, 2004, 2009, 2014, and 2019). Data were extracted, and descriptive, bivariate, and multivariate logistic regression analyses were performed (α=.05). RESULTS: A total of 1944 articles were included; of which, 27.5% presented collaboration between countries. In 2009, 2014, and 2019, collaboration between countries was more likely to occur than at previous time points (P≤.005). Corresponding authors with a higher h-index (P<.05) and authors from Europe and North America (P<.001) were more likely to establish international connections. The possibility of collaboration between countries was higher for animal studies (P<.001) and for articles published by Clinical Oral Implants Research (P=.026). Collaborations between high-income and upper-middle- or lower-middle-income countries were more likely to happen in 2014 and 2019 (P<.05), as well as when the number of authors was higher (P=.015), compared with collaboration between high-income countries. With regard to the continent, European articles were less likely to have collaborations with upper-middle- or lower-middle-income countries (P<.001). CONCLUSIONS: The findings revealed that some parameters related to the study, authors, countries, and journals were statistically associated with the presence of collaboration between countries. However, the bibliometric parameters showed different trends when countries of different incomes established collaboration.

Is atomic layer deposition of silver possible on N95 masks?

Due to the COVID19 outbreak, there has been increasing interest in tailoring, modifying and improving conventional personal protective equipment to increase their service life and make them more effective against viruses and bacteria. Here, atomic layer deposition (ALD) was used to functionalize the filter of N95 mask with nano-islands of silver. X-ray photoelectron spectroscopy and x-ray absorption fine structure were used for ALD silver characterization; microbiological assay was conducted to study the effectiveness of the deposited silver against the air-borne pathogen Staphylococcus aureus (S. aureus). Results showed that silver ALD successfully functionalized the N95 mask at 90 and 120 °C for two different numbers of ALD cycles (1100 and 1500 cycles). The deposited silver nano-islands were stable on the N95 filter media against washing. The leaching of silver nano-islands was studied using inductively coupled plasma mass spectrometry of phosphate-buffered saline solution after soaking the mask in it over predetermined times. <9% of Ag was removed after a maximum time of 4 h that was investigated. Antimicrobial tests showed that for samples functionalized with 1100 ALD cycles of Ag, 76% reduction in S. aureus colony-forming units content was observed after 24 h of biofilm development on the mask surfaces.

Association between industry support and the reporting of study outcomes in randomized clinical trials of dental implant research from the past 20 years.

BACKGROUND: Industry support is a significant funding source in implant dentistry research, not only to provide regulatory processes, but also to validate and promote products through randomized clinical trials (RCTs). However, industry funding should not affect scientific outcomes. PURPOSE: The aim of this study was to investigate whether there is an association between industry support for RCTs in implant dentistry and a greater chance of the reporting of positive outcomes, and whether there are other funding tendencies. MATERIALS AND METHODS: Randomized clinical trials from five implant dentistry journals were reviewed. Data were extracted, and descriptive and inferential statistical analyses (α = 0.05), including bivariate and multivariable logistic regression, and Spearman's correlation were performed. RESULTS: Two hundred eleven RCTs were included. Industry-funded and -unfunded studies presented similar outcomes, in terms of positive and negative results (p ≥ 0.05). North American and European countries received more industry funding, as did high-income countries, which showed well-established collaboration with each other. Clinical Oral Implants Research and Clinical Implant Dentistry and Related Research published 83.6% of industry-funded articles. Industry-funded studies from middle-income countries established more international collaborations with high-income countries than did unfunded studies. Citation numbers were similar for funded and unfunded studies. The chance of RCTs being industry-funded was higher for high-income (odds ratio [OR] = 3.00; 95% confidence interval [CI], 0.99-9.32; p = 0.05) and North American articles (OR = 3.40; 95% CI, 1.37-8.42; p = 0.008) than in lower-middle-income and other continents, respectively. Higher industry funding was associated with specific topics such as "surgical procedures," "prosthodontics topics," and "implant macrodesign" (OR = 4.7; 95% CI, 1.45-15.20; p = 0.010) and with the increase in numbers of institutions (OR = 1.52; 95% CI, 1.16-2.0; p = 0.002). CONCLUSION: The available evidence suggests no association between industry funding and greater chances of the reporting of positive outcomes in implant dentistry RCTs. A strong association was identified in industry trends concerning geographic origins, higher numbers of institutions, and specific research topics.

Analysis of salivary parameters of mucopolysaccharidosis individuals.

Mucopolysaccharidosis (MPS) is a heterogeneous group of rare, chronic, progressive and systemic inherited disorders resulting from deficiency or lack of lysosomal enzymes responsible for the degradation of glycosaminoglycans. Products of nitrosative stress have been previously detected in blood and urine samples of patients with MPS. However, it is unclear whether they are present in the saliva of MPS patients and also if they correlate with salivary parameters such as flow and pH. This study compared the salivary levels of NOX (NO2- + NO3-), nitrite (NO2-), protein (albumin), erythrocyte and leukocyte numbers, as well as the salivary flow rate and pH values of samples obtained from 10 MPS patients and 10 healthy subjects. MPS patients exhibited higher salivary levels of NOX and NO2- when compared to healthy subjects (p < 0.05). Albumin was only detected in six saliva samples of MPS patients and, erythrocytes and leukocytes were detected in 60% and 40% of the MPS patients, respectively. In addition, salivary flow rate and pH averages were statistically lower in this group when compared to healthy samples (p < 0.05). Overall, the data indicates that the salivary levels of NO products can be used in combination with other heath indicators to monitor MPS disorders.

Patient-reported outcome measures and clinical assessment of implant-supported overdentures and fixed prostheses in mandibular edentulous patients: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: A consensus based on patients' perceptions as to whether to use overdentures or fixed prostheses to rehabilitate mandibular edentulous arches is limited. PURPOSE: The purpose of this systematic review and meta-analysis was to compare the patient-reported outcome measures (PROMs) and clinical outcomes associated with implant-supported overdentures and fixed prostheses in edentulous mandibles. MATERIAL AND METHODS: Nine electronic databases were searched for randomized clinical trials (RCTs) and nonrandomized clinical trials (N-RCTs). The risk of bias was assessed by the revised Cochrane risk of bias tool for RCTs (RoB 2) and N-RCT (ROBINS-I). Data sets for oral health-related quality of life (OHRQoL), satisfaction, survival rate, implant probing depth, and marginal bone loss were plotted, and the appropriate analyses were applied by using the Rev Man 5.3 software program. Certainty of evidence was also evaluated by means of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. RESULTS: Ten eligible trials were included and evaluated quantitatively. For 3 domains of OHRQoL, fixed prostheses showed significantly higher quality of life when compared with overdentures regarding functional limitation (P<.001), physical disability (P=.001), and physical pain (P=.003). Fixed prostheses also improved satisfaction, when compared with overdentures for comfort (P=.02), ease of mastication (P<.001), retention (P<.001), and stability (P<.001). The same pattern was observed for overall OHRQoL (P=.01) and satisfaction (P=.01) in which fixed prostheses improved patient satisfaction. Only ease of cleaning presented greater satisfaction for the overdenture group. Clinical parameters did not differ statistically (P>.05) between both types of prosthesis. CONCLUSIONS: Fixed rehabilitations for mandibular edentulous patients seem to be a well-accepted treatment from the patients' oral health perspective. However, mandibular overdentures are no less efficient than fixed prostheses in terms of clinical outcomes.