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Several inflammatory diseases are characterized by a disruption in the equilibrium between the host and its microbiome. Due to the increase in resistance, the use of antibiotics for the widespread, nonspecific killing of microorganisms is at risk. Pro-microbial approaches focused on stimulating or introducing beneficial species antagonistic toward pathobionts may be a viable alternative for restoring the host-microbiome equilibrium. Unfortunately, not all potential probiotic or synbiotic species and even subspecies (to strain level) are equally effective for the designated pathology, leading to conflicting accounts of their efficacy. To assess the extent of these species- and strain-specific effects, 13 probiotic candidates were evaluated for their probiotic and synbiotic potential with glycerol on in vitro oral biofilms, dissemination from biofilms to keratinocytes, and anti-inflammatory activity. Species- and strain-specific effects and efficacies were observed in how they functioned as probiotics or synbiotics by influencing oral pathobionts and commensals within biofilms and affected the dissemination of pathobionts to keratinocytes, ranging from ineffective strains to strains that reduced pathobionts by 3 + log. In addition, a minority of the candidates exhibited the ability to mitigate the inflammatory response of LPS-stimulated monocytes. For a comprehensive assessment of probiotic therapy for oral health, a judicious selection of fully characterized probiotic strains that are specifically tailored to the designated pathology is required. This approach aims to challenge the prevailing perception of probiotics, shifting the focus away from "form over function." Rather than using unproven, hypothetical probiotic strains from known genera or species, one should choose strains that are actually functional in resolving the desired pathology before labelling them probiotics., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Antimicrobial resistance is one of the greatest challenges to global health. While the development of new antimicrobials can combat resistance, low profitability reduces the number of new compounds brought to market. Elucidating the mechanism of action is crucial for developing new antimicrobials. This can become expensive as there are no universally applicable pipelines. Phenotypic heterogeneity of microbial populations resulting from antimicrobial treatment can be captured through flow cytometric fingerprinting. Since antimicrobials are classified into limited groups, the mechanism of action of known compounds can be used for predictive modeling. We demonstrate a cost-effective flow cytometry approach for determining the mechanism of action of new compounds. Cultures of Actinomyces viscosus and Fusobacterium nucleatum were treated with different antimicrobials and measured by flow cytometry. A Gaussian mixture mask was applied over the data to construct phenotypic fingerprints. Fingerprints were used to assess statistical differences between mechanism of action groups and to train random forest classifiers. Classifiers were then used to predict the mechanism of action of cephalothin. Statistical differences were found among the different mechanisms of action groups. Pairwise comparison showed statistical differences for 35 out of 45 pairs for A. viscosus and for 32 out of 45 pairs for F. nucleatum after 3.5 h of treatment. The best-performing random forest classifier yielded a Matthews correlation coefficient of 0.92 and the mechanism of action of cephalothin could be successfully predicted. These findings suggest that flow cytometry can be a cheap and fast alternative for determining the mechanism of action of new antimicrobials.IMPORTANCEIn the context of the emerging threat of antimicrobial resistance, the development of novel antimicrobials is a commonly employed strategy to combat resistance. Elucidating the mechanism of action of novel compounds is crucial in this development but can become expensive, as no universally applicable pipelines currently exist. We present a novel flow cytometry-based approach capable of determining the mechanism of action swiftly and cost-effectively. The workflow aims to accelerate drug discovery and could help facilitate a more targeted approach for antimicrobial treatment of patients., Competing Interests: The authors declare no conflict of interest.

Background/objectives: To systematically review the available evidence concerning the risk factors for gingival recessions (GR) after orthodontic treatment (OT)., Data Collection and Analysis: Data was obtained and collected by systematically searching 3 data bases: Pubmed, EMBASE, and Web of Science until 20 April 2023. Controlled trials, cohort, case-control or cross-sectional studies describing GR or clinical crown height (CCH) after OT were included. The risk of bias in the selected studies was evaluated with the methodological index for non-randomized studies., Results: Forty-eight articles were included, investigating the following six risk factors for GR: 1. OT (n = 21), 2. Type of orthodontic intervention (n = 32), 3. Patient's baseline occlusal and skeletal characteristics (n = 14), 4. Mucogingival characteristics (n = 10), 5. Oral hygiene (n = 9), and 6. Others (n = 12). Significantly higher prevalence, severity and extent of GR were found in orthodontic patients by 10/15, 4/10, and 2/2 articles respectively. 10/16 articles reported significantly more GR and increased CCH in patients where orthodontic incisor proclination was performed. The evidence surrounding maxillary expansion and orthodontic retention was too heterogeneous to allow for? definitive conclusions. Pre-treatment angle classification, ANB, overjet, overbite, arch width and mandibular divergence were found not to be associated with GR (9/14), while pre-treatment crossbite, symphysis height and width were (5/7 studies). A thin gingival biotype, presence of previous GR, baseline width of keratinized gingiva and facial gingival margin thickness were correlated with increased risk of GR after OT by nine articles, while pocket depth was not. Oral hygiene, sex, treatment duration, and oral piercings were found not to be linked with GR in orthodontic patients, while GR was reported to increase with age in orthodontic patients by 50 per cent of the articles investigating this factor. The mean risk of bias for comparative and not comparative studies was 14.17/24 and 9.12/16., Limitations: The selected studies were quite heterogeneous regarding study settings, variables reported and included very limited sample sizes., Conclusion: Although studies regarding the risk factors for GR are relatively abundant, they are very heterogeneous concerning design, studied factors, methodology and reporting, which often leads to contradictory results. Uniform reporting guidelines are urgently needed for future research., Prospero Registration: CRD42020181661., Funding: This research received no funding., (© The Author(s) 2023. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

In our previous studies, Chlorin-e6 (Ce6) demonstrated a significant reduction of microorganisms' viability against multi-species biofilm related to periodontitis while irradiated with blue light. However, the conjugation of Ce6 and antimicrobial peptides, and the incorporation of this photosensitizer in a nanocarrier, is still poorly explored. We hypothesized that chlorin-e6 conjugated to the antimicrobial peptide LL-37 loaded nanoemulsion could inhibit a multi-species biofilm related to periodontitis during photodynamic therapy (PDT), the pre-treatment with hydrogen peroxide was also tested. The nanoemulsion (NE) incorporated with Ce6 was characterized regarding the physiochemical parameters. Images were obtained by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Later, the Ce6 and LL-37 incorporated in NE was submitted to UV-Vis analysis and Reactive Oxygen Species (ROS) assay. Finally, the combined formulation (Ce6+LL-37 in nanoemulsion) was tested against multi-species biofilm related to periodontitis. The formed nanoformulation was kinetically stable, optically transparent with a relatively small droplet diameter (134.2 unloaded and 146.9 loaded), and weak light scattering. The NE system did not impact the standard UV-VIS spectra of Ce6, and the ROS production was improved while Ce6 was incorporated in the NE. The combination of Ce6 and LL-37 in NE was effective to reduce the viability of all bacteria tested. The treatment with hydrogen peroxide previous to PDT significantly impacted bacterial viability. The current aPDT regimen was the best already tested against periodontal biofilm by our research team. Our results suggest that this combined protocol must be exploited for clinical applications in localized infections such as periodontal disease. - Nanoemulsion demonstrated to be an excellent nanocarrier for photodynamic application. - Chlorin-e6 incorporated in nanoemulsion showed great physicochemical and biophotonic parameters. - The combination of chlorin-e6 and LL-37 peptide in nanoemulsion is effective to eliminate periodontal pathogenic bacteria. - The treatment with hydrogen peroxide previous to PDT significantly impacted bacterial viability., Competing Interests: Declaration of Competing Interest This manuscript has been read and approved in final form by all authors and the authors declare no conflicts of interest., (Copyright © 2023. Published by Elsevier B.V.)

Probiotics have demonstrated oral health benefits by influencing the microbiome and the host. Although promising, their current use is potentially constrained by several restrictions. One such limiting factor lies in the prevailing preparation of a probiotic product. To commercialize the probiotic, a shelf stable product is achieved by temporarily inactivating the live probiotic through drying or freeze drying. Even though a lyophilized probiotic can be kept dormant for an extended period of time, their viability can be severely compromised, making their designation as probiotics questionable. Additionally, does the application of an inactive probiotic directly into the oral cavity make sense? While the dormancy may allow for survival on its way towards the gut, does it affect their capacity for oral colonisation? To evaluate this, 21 probiotic product for oral health were analysed for the number of viable (probiotic), culturable (CFU) and dead (postbiotic) cells, to verify whether the commercial products indeed contain what they proclaim. After isolating and uniformly lyophilizing three common probiotic species in a simple yet effective lyoprotective medium, the adhesion to saliva covered hydroxyapatite discs of lyophilized probiotics was compared to fresh or reactivated lyophilized probiotics. Unfortunately, many of the examined products failed to contain the claimed amounts of viable cells, but also the strains used were inadequately characterized and lacked clinical evidence for that unknown strain, questioning their label of a 'probiotic'. Additionally, lyophilized probiotics demonstrated low adhesive capacity compared to their counterparts, prompting the question of why fresh or reactivated probiotics are not currently used., Competing Interests: WT has lectured for BioGaia, one of the anonymized products. The KU Leuven has received a research grant and has conducted several clinical studies for BioGaia. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Van Holm, Lauwens, De Wever, Schuermans, Zayed, Pamuk, Saghi, Fardim, Bernaerts, Boon and Teughels.)

The purpose of this study was to perform an integrative review on the effects of cranberry and grape seed extracts concerning the disinfection of root canals maintaining the strength of the remnant tooth tissues' structure. A bibliographical search was carried out on the PubMed electronic platform using the following key terms: cranberry, grape seed, vaccinium macrocarpon, proanthocyanidin, antibacterial, antimicrobial, decontamination, disinfection, bacteria removal, bacteria eradication, bacteria elimination, endodontic, root canal, faecalis, and strength. The inclusion criteria involved articles published in the English language, until March, 2022, reporting the antibacterial effect of grape seed and cranberry extracts. Of 185 studies identified, 13 studies were selected for the present review. The grape seed extract (GSE), composed of proanthocyanidins, showed an antioxidant activity against the main bacteria found in endodontic secondary infection. The percentage of bacteria removal was recorded at around 96.97% by using GSE. Studies on cranberry extracts, which are composed of proanthocyanidins, revealed antimicrobial effects against bacteria related to periodontitis and dental caries. Additionally, GSE or cranberry allowed the dentin collagen cross-linking that preserved the 3D collagen network leading to the maintenance of the strength of the remnant tooth structure. However, the contaminated smear layer could not be removed by using only GSE or cranberry. Cranberry extracts and GSE revealed a significant antimicrobial activity in endodontic disinfection without changing the mechanical properties of the remnant dentin tissues. Furthermore, those components can be associated with traditional compounds to enhance their antimicrobial effects and eliminate the smear layer., (© 2022. The Author(s), under exclusive licence to The Society of The Nippon Dental University.)

This narrative review celebrates Europe's contribution to the current knowledge on systemically administered antimicrobials in periodontal treatment. Periodontitis is the most frequent chronic noncommunicable human disease. It is caused by dysbiotic bacterial biofilms and is commonly treated with subgingival instrumentation. However, some sites/patients do not respond adequately, and its limitations and shortcomings have been recognized. This has led to the development of alternative or adjunctive therapies. One is the use of antimicrobials to target bacteria in subgingival biofilms in the periodontal pocket, which can be targeted directly through the pocket entrance with a locally delivered antibiotic or systemically by oral, intravenous, or intramuscular methods. Since the early 20th century, several studies on systemic antibiotics have been undertaken and published, especially between 1990 and 2010. Europe's latest contribution to this topic is the first European Federation of Periodontology, S3-level Clinical Practice Guideline, which incorporates recommendations related to the use of adjuncts to treat stage I-III periodontitis. Understanding the etiopathogenesis of periodontal diseases, specifically periodontitis, has influenced the use of systemic periodontal antibiotic therapy. Randomized clinical trials and systematic reviews with meta-analyses have demonstrated the clinical advantages of adjunctive systemic antimicrobials. However, current recommendations are restrictive due to concerns about antibiotic misuse and the increase in microbial antibiotic resistance. European researchers have contributed to the use of systemic antimicrobials in the treatment of periodontitis through clinical trials and by providing rational guidelines. Nowadays, European researchers are exploring alternatives and directing clinical practice by providing evidence-based guidelines to limit the use of systemic antimicrobials., (© 2023 The Authors. Periodontology 2000 published by John Wiley & Sons Ltd.)

Aim: To answer the following PICOS question: "In patients with peri-implantitis, what is the efficacy of surgical therapy with adjunctive systemic or local antimicrobials, in comparison with surgical therapy alone, in terms of pocket probing depth reduction, as assessed in randomized controlled trials (RCTs) with at least 6 months of follow-up?", Materials and Methods: A systematic literature search was conducted. Reduction in mean probing pocket depth (PPD) was the primary outcome. Secondary clinical outcomes were changes in suppuration (%), changes in bleeding on probing (BOP) (%), marginal bone level changes (mm), disease resolution (%), and implant/prosthesis loss (%). Patient-reported outcome measures, possible adverse effects, and oral-health-related quality of life were also extracted if such data were available., Results: Four RCTs assessing the use of locally (two RCTs) and systemically (two RCTs) administered antimicrobial adjuncts to surgical treatment of peri-implantitis, with 6-36-month follow-up, were included. Because of the substantial heterogeneity of interventions between the studies, meta-analysis could not be performed. A reduction in the mean PPD was observed following all the involved surgical treatments, irrespective of the addition of antimicrobials. Except for the effect of systemic antimicrobials on marginal bone level changes and local antimicrobials on BOP, the effect of systemic and local antimicrobials was equivocal for all secondary outcome measures., Conclusions: Based on the limited available evidence, the adjunctive use of the currently tested systemic or local antimicrobials during surgical therapy, in comparison with surgical therapy alone, in patients with peri-implantitis does not seem to improve the clinical efficacy. With regard the use of systemic antimicrobials, only 50% of the cases showed disease resolution after 1 year. There is a lack of studies that consider the sole use of local antimicrobials. Therefore, their true effect remains unclear., (© 2023 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Several oral diseases are characterized by a shift within the oral microbiome towards a pathogenic, dysbiotic composition. Broad-spectrum antimicrobials are often part of patient care. However, because of the rising antibiotic resistance, alternatives are increasingly desirable. Alternatively, supplying beneficial species through probiotics is increasingly showing favorable results. Unfortunately, these probiotics are rarely evaluated comparatively. In this study, the in vitro effects of three known and three novel Lactobacillus strains, together with four novel Streptococcus salivarius strains were comparatively evaluated for antagonistic effects on proximal agar growth, antimicrobial properties of probiotic supernatant and the probiotic's effects on in vitro periodontal biofilms. Strain-specific effects were observed as differences in efficacy between genera and differences within genera. While some of the Lactobacillus candidates were able to reduce the periodontal pathobiont A. actinomycetemcomitans, the S. salivarius strains were not. However, the S. salivarius strains were more effective against periodontal pathobionts P. intermedia, P. gingivalis, and F. nucleatum. Vexingly, most of the Lactobacillus strains also negatively affected the prevalence of commensal species within the biofilms, while this was lower for S. salivarius strains. Both within lactobacilli and streptococci, some strains showed significantly more inhibition of the pathobionts, indicating the importance of proper strain selection. Additionally, some species showed reductions in non-target species, which can result in unexpected and unexplored effects on the whole microbiome., (© 2023. The Author(s).)

Objective: The objective of this review was to assess the accuracy of available means of determining the BBT (buccal bone thickness) and/or BBL (buccal bone level). This was translated into the following research question: What is the accuracy of the available means of visualizing the BBP (buccal bone plate) to establish the BBT and/or the BBL, when compared to control measurements? As control measurements histomorphometric measurements, direct measurements and cone-beam computed tomography (CBCT) measurements in the absence of metal are accepted., Background Data: METHODS: The literary search was performed by searching the databases of MEDLINE, Embase, and Web of Science, up to July 13, 2021. Types of studies included were clinical, in vitro and animal trials, specifically looking into the bone level and/or bone thickness of the buccal bone plate at oral implants. Reference lists were hand searched for relevant articles. Two reviewers performed the data extraction and analysis. Only studies using reliable control measurements to evaluate the accuracy of the tested means of visualizing BBT and/or BBL were included for analysis. The QUADAS-2 tool was used to perform bias analysis on the relevant studies. Extracted data was tabulated to show the differences between test and control measurements for BBT and BBL. For in vitro studies on CBCT measurements of BBT meta-analysis could be performed., Results: A total of 1176 papers were identified in the search. Twenty-two articles were used for data extraction and qualitative analysis. Of these studies nine were animal studies, 9 were in vitro studies and four were human studies. Six animal studies and three human studies provided data on probing. CBCT and sonography as techniques for visualizing the buccal bone plate. Probing at implant sites seems to provide data that correlates with a consistent distance from the BBP. Meta-analysis for probing studies could not be performed due to heterogeneity in the setups of these studies. Eleven studies on CBCT were eligible for inclusion. Of these three were animal studies, the remaining 8 studies were all in vitro studies. Meta-analysis was performed on the accuracy of CBCT for in vitro studies, finding a significant underestimation of the BBT when compared to control measurements by a mean difference of -0.15 mm with 95%CI [-0.26,-0.03]. Three studies were identified on measurement of BBT and/or BBL by sonography. This included one human study and two in vitro studies. The identified studies show a low error when determining the buccal bone level or thickness using sonography. All included studies possess a high risk of bias according to risk of bias analysis, mostly due to selection of the patient., Conclusion: A strong limitation of this systematic review is the inclusion of different studies with heterogeneous designs. Within the limits of this analysis it cannot be concluded that probing is an accurate way of visualizing the BBP. CBCT cannot yet be recommended as a standard diagnostic tool for follow-up of the BBP at oral implants. The application of sonography as a diagnostic tool to visualize the BBP needs further scientific validation., (© 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Periodontitis is a chronic inflammatory gum disease associated with systemic diseases such as cardiovascular diseases., Aim: To investigate the association of systemic blood biomarkers, C-reactive protein (CRP), levels of lipopolysaccharide (LPS), and IgG levels against periodontal pathogens Aggregatibacter actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) with the stability, based on the aortic diameter, the growth rate and the eligibility for surgical intervention, of patients with abdominal aortic aneurysm (AAA)., Methods: Patients with stable AAA (n = 30) and unstable AAA (n = 31) were recruited. The anti- A. actinomycetemcomitans and anti- P. gingivalis IgG levels were analyzed by ELISA, the LPS analysis was performed by using the limulus amebocyte lysate (LAL) test, and plasma levels of CRP were determined using an immune turbidimetric method. The association between these blood systemic biomarkers, AAA features, periodontal clinical parameters and oral microbial profiles were explored. Regression models were used to test the relationship between variables., Results: The presence of antibodies against Pg and Aa, LPS and high CRP concentrations were found in all AAA patients. The IgG levels were similar in patients with stable and unstable AAA (both for Aa and Pg). Among investigated blood biomarkers, only CRP was associated with AAA stability. The amount of LPS in saliva, supra, and subgingival plaque were significantly associated with the systemic LPS (p <0.05)., Conclusions: This post-hoc study emphasizes the presence of antibodies against Pg and Aa, LPS and high CRP concentrations in all AAA patients. The presence of Pg in saliva and subgingival plaque was significantly associated with the blood LPS levels. For further studies investigating periodontitis and systemic diseases, specific predictive blood biomarkers should be considered instead of the use of antibodies alone., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Salhi, Rijkschroeff, Van Hede, Laine, Teughels, Sakalihasan and Lambert.)

Introduction: The aim of this nonrandomized, multicenter controlled clinical trial was to evaluate the impact of leukocyte-platelet-rich fibrin (LPRF) on regenerative endodontic procedures (REPs) of immature permanent teeth in terms of periapical bone healing (PBH) and further root development (RD)., Methods: Healthy patients between 6-25 years with an inflamed or necrotic immature permanent tooth were included and divided between the test (= REP + LPRF) and control (= REP-LPRF) group depending on their compliance and the clinical setting (university hospital or private practice). After receiving REP ± LPRF, the patients were recalled after 3, 6, 12, 24, and 36 months. At each recall session, the teeth were clinically and radiographically (by means of a periapical radiograph [PR]) evaluated. A cone-beam computed tomographic (CBCT) imaging was taken preoperatively and 2 and 3 years postoperatively. PBH and RD were quantitatively and qualitatively assessed., Results: Twenty-nine teeth with a necrotic pulp were included, from which 23 (9 test and 14 control) were analyzed. Three teeth in the test group had a flare-up reaction in the first year after REP. Except for 2 no shows, all the analyzed teeth survived up to 3 years after REP, and, in case of failure, apexification preserved them. Complete PBH was obtained in 91.3% and 87% of the cases based on PR qualitative and quantitative evaluation, respectively, with no significant difference between the groups with respect to the baseline. The PR quantitative change in RD at the last recall session with respect to the baseline was not significant (all P values > .05) in both groups. The qualitative assessment of the type of REP root healing was nonuniform. In the test group, 55.6% of the teeth presented no RD and no apical closure. Only 50% of the 14 teeth assessed with CBCT imaging presented complete PBH. Regarding volumetric measurements on RD 3 years after REP for the change with respect to the baseline in root hard tissue volume, mean root hard tissue thickness, and apical area, the control group performed significantly in favor of RD than the test group (P = .03, .003, and 0.05 respectively). For the volumetric change 3 years after REP with respect to the baseline in root length and maximum root hard tissue thickness, no significant difference (P = .72 and .4, respectively) was found between the groups. The correlation between the PR and CBCT variables assessing RD was weak (root lengthening) to very weak (root thickening)., Conclusions: REP-LPRF seems to be a viable treatment option to obtain PBH and aid further RD of necrotic immature permanent teeth. Caution is needed when evaluating REP with PR., (Copyright © 2021 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

Leucocyte- and platelet rich fibrin (L-PRF) is an autologous biomaterial used in regenerative procedures. It has an antimicrobial activity against P. gingivalis although the mechanism is not fully understood. It was hypothesized that L-PRF exudate releases hydrogen peroxide and antimicrobial peptides that inhibit P. gingivalis growth. Agar plate and planktonic culture experiments showed that the antimicrobial effect of L-PRF exudate against P. gingivalis was supressed by peroxidase or pepsin exposure. In developing multi-species biofilms, the antimicrobial effect of L-PRF exudate was blocked only by peroxidase, increasing P. gingivalis growth with 1.3 log genome equivalents. However, no effect was shown on other bacteria. Pre-formed multi-species biofilm trials showed no antimicrobial effect of L-PRF exudate against P. gingivalis or other species. Our findings showed that L-PRF exudate may release peroxide and peptides, which may be responsible for its antimicrobial effect against P. gingivalis . In addition, L-PRF exudate had an antimicrobial effect against P. gingivalis in an in vitro developing multi-species biofilm., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Rodríguez Sánchez, Verspecht, Castro, Pauwels, Andrés, Quirynen and Teughels.)

Peri-implant diseases are one of the main causes of dental implant failure. New strategies for dental implants manufacturing have been developed to prevent the accumulation of bacteria and related inflammatory reactions. The main aim of this work was to develop laser-treated titanium surfaces covered with silver that generate a electrical dipole to inhibit the oral bacteria accumulation. Two approaches were developed for that purpose. In one approach a pattern of different titanium dioxide thickness was produced on the titanium surface, using a Q-Switched Nd:YAG laser system operating at 1064 nm. The second approach was to incorporate silver particles on a laser textured titanium surface. The incorporation of the silver was performed by laser sintering and hot-pressing approaches. The anti-biofilm effect of the discs were tested against biofilms involving 14 different bacterial strains growth for 24 and 72 hr. The morphological aspects of the surfaces were evaluated by optical and field emission guns scanning electronical microscopy (FEGSEM) and therefore the wettability and roughness were also assessed. Physicochemical analyses revealed that the test surfaces were hydrophilic and moderately rough. The oxidized titanium surfaces showed no signs of antibacterial effects when compared to polished discs. However, the discs with silver revealed a decrease of accumulation of Porphyromonas gingivalis and Prevotella intermedia strains. Thus, the combination of Nd:YAG laser irradiation and hot-pressing was effective to produce silver-based patterns on titanium surfaces to inhibit the growth of pathogenic bacterial species. The laser parameters can be optimized to achieve different patterns, roughness, and thickness of the modified titanium layer regarding the type and region of the implant., (© 2021 Wiley Periodicals LLC.)

Background: Choline-stabilized orthosilicic acid (CS-OSA) was previously found to stimulate bone collagen formation in osteopenia and to improve biomarkers of cartilage degradation in knee osteoarthritis. The aim of the present study was to investigate the effect of oral administration of CS-OSA on clinical symptoms of peri-implantitis and the associated bone loss., Methods: Twenty-one patients with peri-implantitis were randomized in CS-OSA or placebo groups. After initial clinical and cone beam computed tomography (CBCT) measurements [probing pocket depth (PPD), bleeding on probing (BOP), mucosal recession (REC), distance from implant shoulder to alveolar crest (IS-AC) and distance from implant shoulder to first bone-to-implant contact (IS-BIC)], flap operations were performed at the peri-implantitis sites. All patients were instructed to use either placebo or CS-OSA capsules twice a day for 1 year. Measurements were repeated 6 and 12 months after randomization., Results: The data of 18 patients (36 implants) were used in the per protocol analysis. PPD and BOP improved significantly (p < 0.05) compared to baseline for both groups after 6 and 12 months. However, REC significantly increased in the placebo group but not in the CS-OSA group. The change in REC over 6 and 12 months was significantly different between groups (p < 0.01). IS-BIC and IS-AC measurements remained stable in the CS-OSA group whereas in the placebo group, both parameters increased significantly after 6 and 12 months. The change in IS-BIC over 12 months was significantly different between groups (p < 0.05)., Conclusion: The results of this preliminary study suggest that CS-OSA may stabilize and even prevent further bone loss after surgical peri-implantitis treatment and support mucosal tissue healing. Trial registration The trial was retrospectively registered at ISRCTN registry, registration number: ISRCTN14348802, registration date: 24/06/2020., (© 2021. The Author(s).)

Background: The association of scaling and root planing (SRP) with systemic metronidazole (MTZ) plus amoxicillin (AMX) has shown to be an effective treatment protocol, particularly for periodontitis stages III and IV, generalized. More recently, probiotics have also been suggested as a promising adjunctive treatment for periodontal diseases due to their antimicrobial and anti-inflammatory properties. Therefore, the aim of this randomized clinical trial (RCT) is to evaluate the clinical, microbiological, and immunological effects of probiotics as adjuncts to SRP alone or with MTZ+AMX in the treatment of periodontitis., Methods: Subjects with periodontitis are being randomly assigned to receive (i) SRP alone, or with (ii) two probiotic lozenges/day for 90 days (Prob), (iii) MTZ (400 mg) and AMX (500 mg) thrice a day (TID) for 14 days (MTZ+AMX), or (iv) Prob and MTZ+AMX. Subjects are being monitored for up to 12 months post-treatment. Nine subgingival plaque samples per patient are being collected at baseline and at 3, 6, and 12 months post-therapy and analyzed by checkerboard DNA-DNA hybridization for 40 bacterial species. Peripheral blood and gingival crevicular fluid (GCF) of four randomly selected periodontal sites will be analyzed by means of a multiplex fluorescent bead-based immunoassay for 17 cyto/chemokines., Statistical Analyses: The significance of differences in each group (over the course of the study) will be sought using repeated measures ANOVA or Friedman tests and among groups (at each time point) using either ANOVA/ANCOVA or Kruskal-Wallis tests, depending on normality of the data. The chi-square test will be used to compare differences in the frequency of subjects achieving the clinical endpoint for treatment (≤ 4 sites with PD ≥ 5 mm) at 1 year and of self-perceived adverse effects. A stepwise forward logistic regression analysis will be performed in order to investigate the impact of different predictor variables on the percentage of patients achieving the clinical endpoint for treatment. The Number Needed to Treat (NNT) with different treatment protocols will be also calculated. Statistical significance will be set at 5%., Trial Registration: ClinicalTrials.gov NCT03733379. Registered on November 7, 2018.

Oral diseases (e.g., dental caries, periodontitis) are developed when the healthy oral microbiome is imbalanced allowing the increase of pathobiont strains. Common practice to prevent or treat such diseases is the use of antiseptics, like chlorhexidine. However, the impact of these antiseptics on the composition and metabolic activity of the oral microbiome is poorly addressed. Using two types of oral biofilms-a 14-species community (more controllable) and human tongue microbiota (more representative)-the impact of short-term chlorhexidine exposure was explored in-depth. In both models, oral biofilms treated with chlorhexidine exhibited a pattern of inactivation (>3 log units) and fast regrowth to the initial bacterial concentrations. Moreover, the chlorhexidine treatment induced profound shifts in microbiota composition and metabolic activity. In some cases, disease associated traits were increased (such as higher abundance of pathobiont strains or shift in high lactate production). Our results highlight the need for alternative treatments that selectively target the disease-associated bacteria in the biofilm without targeting the commensal microorganisms.

Purpose: Sinus floor elevation (SFE) and simultaneous implant placement is predictable and reproducible. However, the graft material for the antral cavity remains a topic of debate. Considering the high osteogenic potential of the sinus membrane, most graft materials are generally accepted. This study aimed to assess the outcome of simultaneous SFE and implant placement, using leukocyte- and platelet-rich fibrin (LPRF) as a sole graft material., Materials and Methods: This study was designed as a single cohort prospective study. Clinical and radiographic measurements (cone beam computed tomography [CBCT]) were performed immediately after implant placement and at abutment connection (6 months later). The amount of newly formed bone was linearly recorded on cross-sectional images. Four measurements (mesial, distal, buccal, palatal) were registered with the axis of the implant as reference., Results: Six lateral and 22 transalveolar SFEs were performed in 26 patients with simultaneous implant placement. Six months after surgery, 27/29 implants were clinically integrated. The mean vertical bone gain was 3.4 ± 1.2 mm and 5.4 ± 1.5 mm for transalveolar SFE and lateral SFE, respectively. The level of the new sinus floor was in all cases in continuation with the apex of the implant, and the peri-implant crestal bone height was stable., Conclusion: L-PRF as a sole graft material during simultaneous SFE and implant placement proved to be a practical, safe, and economical subsinus graft material, resulting in natural bone formation.

Purpose: The leukocyte- and platelet-rich fibrin block (L-PRF block) is a composite graft that combines a xenograft that is acting as a scaffold with L-PRF membranes that serve as a bioactive nodule with osteoinductive capacity. This study evaluated the properties of the L-PRF block and its components in terms of release of growth factors, cellular content, and structure., Materials and Methods: The concentration of transforming growth factor-β1 (TGF-β1), vascular endothelial growth factor (VEGF), platelet-derived growth factor-AB (PDGF-AB) and bone morphogenetic protein-1 (BMP-1) released by a L-PRF membrane (mb) and a L-PRF block were examined with ELISA for five time intervals (0 to 4 hours, 4 hours to 1 day, 1 to 3 days, 3 to 7 days, 7 to 14 days). Those levels in L-PRF exudate and liquid fibrinogen were also evaluated. The cellular content of the liquid fibrinogen, L-PRF membrane and exudate was calculated. The L-PRF block was also analyzed by means of a microCT scan and scanning electron microscopy (SEM)., Results: TGF-β1 was the most released growth factor after 14 days, followed by PDGF-AB, VEGF, and BMP-1. All L-PRF blocks constantly released the four growth factors up to 14 days. L-PRF membrane and liquid fibrinogen presented high concentration of leukocytes and platelets. The microCT and SEM images revealed the bone substitute particles surrounded by platelets and leukocytes, embedded in a dens fibrin network., Conclusion: The L-PRF block consists of deproteinized bovine bone mineral particles surrounded by platelets and leukocytes, embedded in a fibrin network that releases growth factors up to 14 days.

There is evidence that pathogenic bacteria can adapt to antiseptics upon repeated exposure. More alarming is the concomitant increase in antibiotic resistance that has been described for some pathogens. Unfortunately, effects of adaptation and cross-adaptation are hardly known for oral pathogens, which are very frequently exposed to antiseptics. Therefore, this study aimed to determine the in vitro increase in minimum inhibitory concentrations (MICs) in oral pathogens after repeated exposure to chlorhexidine or cetylpyridinium chloride, to examine if (cross-)adaptation to antiseptics/antibiotics occurs, if (cross-)adaptation is reversible and what the potential underlying mechanisms are. When the pathogens were exposed to antiseptics, their MICs significantly increased. This increase was in general at least partially conserved after regrowth without antiseptics. Some of the adapted species also showed cross-adaptation, as shown by increased MICs of antibiotics and the other antiseptic. In most antiseptic-adapted bacteria, cell-surface hydrophobicity was increased and mass-spectrometry analysis revealed changes in expression of proteins involved in a wide range of functional domains. These in vitro data shows the adaptation and cross-adaptation of oral pathogens to antiseptics and antibiotics. This was related to changes in cell surface hydrophobicity and in expression of proteins involved in membrane transport, virulence, oxidative stress protection and metabolism.

Statement of Problem: Implant-based prosthetic solutions can be time consuming. If implants can be placed successfully with a guide, surgery time can be reduced., Purpose: The purpose of this randomized controlled clinical trial was to assess implant outcomes, both clinical and radiological, comparing guided with nonguided implant placement after 3 years of follow-up., Material and Methods: A total of 314 implants were placed in 72 jaws (60 participants). The jaws were randomly assigned to 1 of the 6 treatment groups: Materialise Universal/mucosa (Mat Mu), Materialise Universal/bone (Mat Bo), Facilitate/mucosa (Fac Mu), Facilitate/bone (Fac Bo), freehand navigation (Freehand), and a pilot-drill template (Templ). Radiographic and clinical parameters (bone loss, pocket probing depth, bleeding on probing, and plaque scores) were recorded at the time of implant placement, prosthesis installment (baseline), and 1-year, 2-year, and 3-year follow-up. Analysis was performed using a linear mixed model, and correction for simultaneous hypothesis was made according to Sidak (α=.05)., Results: Three participants left the study before the 3-year follow-up; hence, 302 implants in 69 jaws were included in this study. None of the implants failed. The mean marginal bone loss after the third year of loading was 0.7 ±1.3 mm for the guided surgery group and 0.5 ±0.6 mm for the control group. No significant intergroup or follow-up period differences were observed (P>.05). In the guided surgery groups, the mean number of surfaces with bleeding on probing and plaque at 3-year follow-up was 1.7 ±1.5 and 1.7 ±1.7, respectively; for the control groups, this was 1.6 ±1.4 and 1.6 ±1.6, respectively. The mean pocket probing depth was 3.0 ±1.3 mm for the guided group and 2.6 ±1.0 mm for the control group. No significant differences were found (P>.1)., Conclusions: Within the limitation of this study, no statistically significant differences could be found between the guided group and the control group at the 3-year follow-up., (Copyright © 2018 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Periodontal health is defined by absence of clinically detectable inflammation. There is a biological level of immune surveillance that is consistent with clinical gingival health and homeostasis. Clinical gingival health may be found in a periodontium that is intact, i.e. without clinical attachment loss or bone loss, and on a reduced periodontium in either a non-periodontitis patient (e.g. in patients with some form of gingival recession or following crown lengthening surgery) or in a patient with a history of periodontitis who is currently periodontally stable. Clinical gingival health can be restored following treatment of gingivitis and periodontitis. However, the treated and stable periodontitis patient with current gingival health remains at increased risk of recurrent periodontitis, and accordingly, must be closely monitored. Two broad categories of gingival diseases include non-dental plaque biofilm-induced gingival diseases and dental plaque-induced gingivitis. Non-dental plaque biofilm-induced gingival diseases include a variety of conditions that are not caused by plaque and usually do not resolve following plaque removal. Such lesions may be manifestations of a systemic condition or may be localized to the oral cavity. Dental plaque-induced gingivitis has a variety of clinical signs and symptoms, and both local predisposing factors and systemic modifying factors can affect its extent, severity, and progression. Dental plaque-induced gingivitis may arise on an intact periodontium or on a reduced periodontium in either a non-periodontitis patient or in a currently stable "periodontitis patient" i.e. successfully treated, in whom clinical inflammation has been eliminated (or substantially reduced). A periodontitis patient with gingival inflammation remains a periodontitis patient (Figure 1), and comprehensive risk assessment and management are imperative to ensure early prevention and/or treatment of recurrent/progressive periodontitis. Precision dental medicine defines a patient-centered approach to care, and therefore, creates differences in the way in which a "case" of gingival health or gingivitis is defined for clinical practice as opposed to epidemiologically in population prevalence surveys. Thus, case definitions of gingival health and gingivitis are presented for both purposes. While gingival health and gingivitis have many clinical features, case definitions are primarily predicated on presence or absence of bleeding on probing. Here we classify gingival health and gingival diseases/conditions, along with a summary table of diagnostic features for defining health and gingivitis in various clinical situations., (© 2018 American Academy of Periodontology and European Federation of Periodontology.)

Objectives: Composites may undergo biodegradation in the oral cavity. The objective was to investigate the effect of single- and multi-species biofilms on the surface roughness and topography of two composites., Methods: Disk-shaped specimens of a paste-like, Bis-GMA-free (Gradia Direct Anterior, GC), and a flowable, Bis-GMA-based composite (Tetric EvoFlow, Ivoclar-Vivadent) were prepared. After ethylene-oxide sterilization (38°C), specimens (n=3) were incubated with Streptococcus mutans or mixed bacterial culture (Streptococcus mutans, Streptococcus sanguinis, Actinomyces naeslundii and Fusobacterium nucleatum). As negative controls, unexposed specimens and specimens exposed to sterile medium (BHI) were used. Specimens exposed to acidified BHI medium (pH=5) and enzymatic solution of cholesterol esterase served as positive control. Following 6-week incubation, the attached biofilms were collected for real-time PCR assessment, after which the surface roughness and topography of the specimens were analyzed with atomic force microscopy. Surface hydrophilicity/hydrophobicity was determined by contact angle measurements. Biofilm structure was analyzed with scanning electron microscopy., Results: Even though multi-species biofilms were thicker, with more cells attached, they did not significantly affect the surface roughness of the composites. On the other hand, S. mutans alone significantly increased the roughness of Tetric by 40.3%, while its effect on Gradia was lower (12%). The total amount of attached bacteria, however, did not differ between the composites., Conclusions: S. mutans can increase the surface roughness of composites, depending on their composition. This ability of S. mutans is, however, mitigated in co-culture with other species. In particular, bacterial esterases seem to be responsible for the increased composite surface roughness upon biofilms exposure., Clinical Significance: Cariogenic bacteria can degrade composites, thereby increasing the surface roughness. Increased roughness and subsequent improved bacterial accumulation may facilitate the development of secondary caries around composites, which is the most common reason for the restoration failure., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

During the last decade an increased interest in alternative, preventive, and therapeutic strategies in dentistry has arisen. Probiotics are living microorganisms which, if administered in sufficient amounts, provide a health benefit to the host. Their precise mechanisms of action have not been identified, but they are able to interfere with the imbalance occurring in biofilm-associated infections. In other fields of medicine, mainly in gastroenterology, their usefulness is already proven. Concerning oral threats, probiotic bacteria may reduce the numbers of pathogens associated with dental caries (mutans streptococci). Clinically, results are encouraging, but further research is needed to demonstrate apparent effects of certain probiotic strains on oral health as well as their desired concentration and vehicle. The use of probiotics in prevention and treatment of caries, periodontal diseases, halitosis, and other oral diseases needs to be further investigated.

Purpose: To compare the subgingival microbiota around two differently designed implant systems that were in function for more than 12 years in a randomised split-mouth study design, and to compare the outcome with natural dentition., Materials and Methods: A total of 18 partially edentulous patients received at least two TiOblast™ (Astra Tech) and two Brånemark (Nobel Biocare) implants following a split-mouth design. At the last follow-up visit, periodontal parameters (probing depth, bleeding on probing and plaque) were recorded and intraoral radiographs were taken to calculate bone loss. Subgingival plaque samples were collected for culture, qPCR and checkerboard DNA-DNA hybridisation analysis. These data were related to implant design and bone loss. This study setup allowed a comparison of 34 Astra Tech (Impl A) with 32 Brånemark (Impl B) implants., Results: During the 12-year follow up, five patients dropped out. One Brånemark implant was lost before abutment connection in a dropout patient. Mean bone loss between loading and year 12 was 0.7 mm (range: -0.8-5.8) (Impl A), and 0.4 mm (range: -1.1-4.1) (Impl B). No significant microbiological differences (qualitative and quantitative) could be observed between both implant types. Compared to teeth, subgingival plaque samples from implants did not reach the concentration of pathogens, even after 12 years of function., Conclusions: These data show that both implant systems (with differences in macro-design and surface characteristics), in patients with good oral hygiene and a stable periodontal condition, can maintain a successful treatment outcome without significant subgingival microbiological differences after 12 years of loading. The presence of periodontopathogens did not necessarily result in bone loss.

Introduction: Bacterial plaque is an etiologic factor in the development of gingival inflammation and periodontitis. The presence of orthodontic bands and brackets influences plaque growth and maturation. The purposes of this research were to monitor microbiologic and periodontal changes after placement of orthodontic attachments over a 1-year period and to link these changes to alterations in cytokine concentrations in the gingival crevicular fluid (GCF)., Methods: This longitudinal split-mouth trial included 24 patients. Supragingival and subgingival plaque composition, probing depth, bleeding on probing, and GCF flow and composition were assessed at baseline (Tb) and after 1 year (T52). A statistical comparison was made over time and between the banded and bonded sites. Prognostic factors for the clinical reaction at T52 in the GCF at Tb were determined., Results: Between Tb and T52, the pathogenicity of the plaque and all periodontal parameters increased significantly, but intersite differences were not seen, except for bleeding on probing. The cytokine concentrations in the GCF did not differ significantly between the sites or between Tb and T52. The interleukin-6 concentration in the GCF at Tb was a significant predictive value for the GCF flow at T52 (P <0.05). The same relationship was found between the interleukin-8 concentration at Tb and the increase in probing depth at T52 (P <0.05)., Conclusions: Interleukin-6 and interleukin-8 concentrations before orthodontic treatment were shown to be significant predictive factors for some potential inflammatory parameters during treatment., (Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

Background: As in other fields of healthcare, probiotics have been introduced for prevention and treatment of periodontal diseases., Objective: This review was initiated to explore whether the use of probiotics can influence the periodontal microbiota and periodontal health., Materials and Methods: Literature on the mode of action of oral probiotics was reviewed and a systematic review was performed on the microbiological and clinical effects of oral probiotics on periodontal health., Results: Three animal and 11 in vivo human studies were retrieved. Six studies reported on microbiological effects whereas eight studies report on clinical effects. Seven studies were performed on healthy or gingivitis patients and four studies on periodontitis patients. Many of the retrieved studies are pilot in nature and with low quality. The high degree of heterogeneity between studies hampered analysis., Conclusion: Taking into consideration all limitations, the currently available data indicate an effect of probiotics on the oral microbiota and a more limited effect on clinical periodontal outcome measures. However, there is an urgent need for properly conducted clinical trials where probiotics are used as adjuncts to standard periodontal care, similar to antibiotics, using probiotic strains with, at least at an in vitro level, proven periodontal probiotic effects., (© 2011 John Wiley & Sons A/S.)

The aim of this longitudinal study was to monitor patients' microbiological and clinical parameters from bracket placement up to 3 months post-treatment. Twenty-four patients (10 males and 14 females, aged 14.6 ± 1.0 years) were included in this investigation. Microbiology (sub- and supragingival), periodontal probing depth (PPD), bleeding on probing (BOP), and gingival crevicular fluid (GCF) flow were assessed at baseline (T1), at bracket removal (T2), and 3 months post-treatment (T3). A statistical comparison was made over time and between the banded, bonded, and control sites. Repeated measurements on patients were taken into account by modelling the patients as a random factor. Except for PPD and BOP, values were log-transformed before analysis. Corrections for simultaneous hypothesis testing were performed via simulation. The results demonstrated that sub- and supragingival colony-forming units ratio (CFU ratio aerobe/anaerobe) decreased significantly (relatively more anaerobes) at T2 compared with T1. Between T2 and T3 no significant increase in CFU ratio was seen, resulting in a significantly lower CFU ratio at T3 compared with T1 for subgingival plaque. The difference concerning supragingival plaque between T3 and T1 was not significant. Clinical parameters PPD, POB, and GCF flow showed a significant increase between T1 and T2. Between T2 and T3 these variables decreased significantly but remained significantly higher than at T1 [except for BOP values at the bonded sites (P = 0.0646)]. Placement of fixed orthodontic appliances has an influence both on microbial and clinical periodontal parameters, which were only partly normalized, 3 months following the removal of the appliances.

Objective: The inherent deformation and two-dimensional nature of panoramic radiographs jeopardise their interpretation and quantitative measurements. This study aims to estimate the degree of underestimation of available mesio-distal bone in the premolar area (comparing panoramic radiographs with multi-slice/cone-beam computer tomography [CT]) to determine the prevalence, width, length and position of the bony canal [artery] in the lateral sinus wall and to explore the prevalence, width and length of another (newly detected) bony canal at the palatal aspect of the upper canine., Material and Methods: The distance between the distal side of the canine/first premolar and the mesial side of the first molar or the anterior wall of the maxillary sinus was measured on panoramic radiographs and corresponding multi-slice/cone-beam CT images (65 patients). Measurements were made at apical, mid-radicular and crestal regions, parallel to the occlusal plane. The presence and dimensions of the two above-mentioned intra-osseous canals were verified on multi-slice CT scans (144 patients) using reformatted cross-sectional images and/or axial slices., Results: For all 65 patients, panoramic radiographs underscored the mesio-distal distance of available bone in the upper premolar region (mean 2.9 mm, range 0.1-7.5 mm). An intra-osseous canal in the lateral maxillary sinus wall was clearly visible in 49.5% of the cases (mean diameter 1.4 mm). In the canine region, a bony canal was obvious in 32.9% of the cases, with a mean diameter of 1.23 mm. For both canals, there was no correlation between diameter and patient's age., Conclusions: Based on the present data, cone-beam CT imaging can be recommended for visualising anatomical structures during planning of sinus augmentation procedures., (© 2010 John Wiley & Sons A/S.)

The aim of the study was to evaluate the effects of Listerine, Meridol, and Perioaid on the viability and total number of bacteria in established biofilms using an in vitro model under hydrodynamic conditions. Biofilms of Aggregatibacter actinomycetemcomitans were placed in a modified Robbins device and rinsed twice daily during 4 days. Bacteria were quantified by culture and quantitative polymerase chain reaction. Visualization of the samples was performed by scanning electron and confocal laser scanning microscopy, combined with a fluorescent vital staining. All three mouthrinses caused a significant reduction in the number of cultivable A. actinomycetemcomitans in a biofilm. Perioaid was significantly the most powerful in killing the biofilm-protected bacteria and also in counteracting the development of thick dense microbial communities. The total amount of bacteria was not significantly affected by Listerine and Meridol.

Objective: To assess the clinical and microbiological efficacy of a 0.05% chlorhexidine and 0.05% cetyl-pyridinium chloride mouth rinse in supportive periodontal care (SPC) in patients with inadequate plaque control., Material and Methods: The study was a randomized, double-blinded, placebo-controlled clinical trial in patients with moderate to severe chronic periodontitis under SPC with an inadequate plaque control (Turesky index >1). After supragingival prophylaxis and oral hygiene reinforcement, participants rinsed twice a day for 3 months with the test or placebo solutions, in addition to conventional hygiene. Primary clinical outcome variables included plaque and gingival indices. As secondary outcomes, periodontal and microbiological variables were studied. ancova and chi(2) tests were used to compare the variables., Results: Forty-seven patients (22 placebo and 25 test group) participated. After 3 months, plaque levels increased in the placebo group, while diminished in the test group (p<0.001). Similar effects were found for bleeding on probing. The other clinical parameters did not show significant differences. Microbiological variables demonstrated inter-group significant reductions in subgingival counts of Fusobacterium nucleatum and Prevotella intermedia and a decrease of the total bacterial counts in saliva., Conclusions: The tested mouth rinse demonstrated efficacy in reducing plaque and gingivitis, as well as in decreasing the microbial load in saliva and gingival sulcus.

Aim: To monitor the intra-oral microbiological changes after full-mouth extraction using quantitative polymerase chain reaction (qPCR)., Material and Methods: Nine patients with severe, aggressive periodontitis, for whom a full-mouth tooth extraction was the only remaining treatment option were recruited. Before and 6 months after extraction, microbial samples were obtained (tongue, saliva and subgingival plaque) and analysed by qPCR., Results: The elimination of subgingival niches, by extraction of all natural teeth, resulted in a 3-log reduction of Porphyromonas gingivalis and Tannerella forsythia, and more modest reductions of Aggregatibacter actinomycetemcomitans and Prevotella intermedia. However, the detection frequencies of these periodontopathogens in saliva and on the tongue remained unchanged after full-mouth tooth extraction., Conclusion: In contrast to what has been believed so far, full-mouth tooth extraction does not result in eradication of all periodontopathogens but only in a significant reduction. The clinical consequences of this observation remain speculative.

Aim: Measurement of volatile sulphur compounds (VSC) by portable sulphur monitors (Halimeter, OralChroma) is a common practice for diagnosis of oral malodour. In this study, the clinical value of these devices was examined., Materials and Methods: Two hundred and eighty patients with bad breath complaints attending a halitosis consultation were enrolled. Organoleptic scores were given by a trained and calibrated judge, before measurement of the VSC levels (Halimeter, OralChroma), to avoid any bias., Results: Significant correlations were found between the organoleptic assessment, the Halimeter, and the OralChroma (R=0.74 for organoleptic versus Halimeter; 0.66 for organoleptic versus OralChroma; 0.63 for Halimeterversus OralChroma). The sensitivity and specificity (with regard to the organoleptic score) to detect patients with/without oral malodour for the Halimeter were 63% and 98%, respectively, and for the OralChroma 69% and 100% when using the cutoffs suggested by the manufacturer. By lowering these values, sensitivity could be improved without a significant decrease in specificity (both devices)., Conclusions: We concluded that the measurement of the VSC levels can be used as an adjunct to the organoleptic assessment. Thresholds should be revisited in order to improve their clinical utility. These devices can prove the absence of malodour in case of pseudo-halitosis.

Objective: To test the hypothesis that there are differences in total bacterial counts and capacity for biofilm formation between seven different bracket types., Material and Methods: By means of an in vitro experiment, seven commercially available bracket systems (Damon [A], Clarity [B], Mystique [C], Speed [D], Victory MBT [E], Micro-loc [F], and Generus [G]) were compared. A total of 25 premolar brackets of each bracket system were incubated in brain heart infusion medium containing the saliva and bacteria of two orthodontic patients. After 72 hours, the amounts of aerobe and anaerobe bacteria were determined by counting the colony-forming units (CFU). The CFU ratio (aerobe/anaerobe) also was calculated, and the black pigmented bacteria were analyzed., Results: Significant differences between the different bracket types in terms of biofilm formation were found. Bracket types can be arbitrarily divided into low, intermediate, and high plaque-retaining brackets. The group with low adhesion consists of bracket types E, F, and G; the group with high adhesion of bracket types A, B, and C; and type D exhibits intermediate adhesion. The group with high microbial adhesion (A, B, and C) did present significantly lower CFU ratios (aerobe/anaerobe) than were exhibited by the other bracket systems (P < .05)., Conclusion: The hypothesis is accepted. Orthodontic brackets serve as different loci for biofilm formation; in this in vitro study, significant differences were noted between the different types of brackets.

Objective: This systematic review was initiated to explore the critical horizontal interproximal and buccal bone dimensions around implants for an optimal aesthetic outcome., Materials and Methods: Pubmed, the Cochrane and the ISI web of Science databases were searched to identify eligible human studies that reflect on the aesthetic outcome of implants in relation to the thickness of the buccal bone after osteotomy preparation, and in relation to the tooth-to-implant or interimplant distance. Vertical bone dimensions were not considered., Results and Discussion: Articles relating horizontal buccal bone dimensions to aesthetic outcome could not be retrieved. The relation between horizontal buccal bone dimensions and vertical bone resorption could also not be confirmed. In relation to horizontal interproximal bone dimensions, some uniformity was detected among the limited number of articles., Conclusions: Interproximally, a 3 mm interelement distance seems to result more frequently in an adequate papillary fill. In the bucco-oral direction, there is insufficient evidence to set a threshold for minimal buccal bone thickness to ensure an optimal aesthetic outcome. Many additional factors appear to be of importance and interact with each other.

Aim: The aim of this study was to radiologically evaluate the impact of replacement therapy by monitoring bone density changes and alveolar bone level in periodontal pockets in a dog model., Material and Methods: Eight male beagle dogs with moderate periodontitis were enrolled in this split-mouth, double-blind randomized trial with ethical approval. Periodontal defects were surgically created bilaterally in the lower jaw. Four months later, the defects were randomly assigned to initial therapy (scaling and root planing) alone (control sites), or combined with multiple subgingival application of beneficial species. Intra-oral follow-up radiography was performed at this stage and 3 months later to verify the treatment effect., Results: The bone density within periodontal pockets treated with beneficial bacteria improved significantly after 12 weeks, while this was non-significant for the control pockets, receiving a single root planing at baseline. There was a significant increase in the bone level at the end of the study for the pockets receiving beneficial bacteria. Again, no significance was noted for the control pockets., Conclusions: This pilot study indicates the potential effect of a subgingival application of beneficial species in periodontal pockets, and illustrates the strength of standardized follow-up radiography to evaluate the effects of different treatment strategies on bone re-modelling.

Background: In the past few decades, more patients have been treated orthodontically, but no longitudinal study has compared orthodontic bands and brackets microbiologically and clinically., Methods: This longitudinal trial (split-mouth design) included 24 patients. Microbiology (sub- and supragingival), probing depth (PD), bleeding on probing (BOP), and gingival crevicular fluid flow (GCF) were assessed at baseline (band placement) and at weeks 18 (bracket bonding) 20, 24, and 36. A statistical comparison was made over time and among the banded, bonded, and control sites., Results: The aerobe/anaerobe ratio of sub- and supragingival colony forming units decreased significantly (relatively more anaerobes) over the study period for the banded and bonded sites (P <0.001). This decrease was accompanied by significant elevations in PD, BOP, and GCF. These changes occurred faster after bonding compared to banding. No significant changes were observed 18 weeks after banding with the exception of increased PD (P <0.001). At week 36, all microbial and clinical variables at the bonded site had changed significantly in the negative direction (P <0.001) compared to week 18. The control sites did not show any significant changes over time, indicating that the effects were localized., Conclusions: The placement of fixed orthodontic appliances had a significant impact on microbial and clinical variables. The changes occurred faster at the bonded sites compared to the banded sites, probably because wire insertion caused difficulties in approximal cleaning. Over the long term, banding did not lead to more adverse microbial and periodontal effects than bonding.

Objectives: This randomized clinical trial compares the usefulness of pre- and post-operative antibiotics while strict asepsis was followed during periodontal surgery., Material and Methods: Two groups of 40 consecutive patients each with fully or partially edentulous jaws were enrolled. Antibiotics group (GrAB(+)): 23 men, mean age 60, 128 implants, received oral amoxicillin 1 g, 1 h pre-operatively and 2 g for 2 days post-operatively. Non-antibiotics group (GrAB(-)): 20 men, mean age 57, 119 implants, received no antibiotics. Bacterial samples were taken from the peri-oral skin before and at the end of surgery. In 12 patients in each group, samples were also taken from the nares. A VAS questionnaire evaluated symptoms of infection/inflammation by both the patient and the periodontologist at suture removal., Results: There were no significant differences between both groups, neither for the clinical parameters nor for the microbiota. Staphylococcus aureus was detected in the nares of one patient only. The patients' subjective perception of post-operative discomfort was significantly smaller in the group receiving antibiotics. Three patients lost one or two implants., Conclusions: Antibiotics do not provide significant advantages concerning post-operative infections in case of proper asepsis. It also does not reduce peri-oral microbial contamination. It does on the other hand reduce post-operative discomfort.

Aim: This study aimed to assess the influence of systemic and local bone and intra-oral factors on the occurrence of early TiUnite implant failures., Material and Methods: A total of 283 consecutive patients (187 females; mean age 56.2), who received a total of 720 TiUnite implants, at the Department of Periodontology of the University Hospital of the Catholic University of Leuven, were prospectively followed. The following aspects were particularly assessed: hypertension, cardiac problems, gastric problems, osteoporosis, hypo- or hyperthyroid, hypercholesterolaemia, asthma, diabetes types I or II, Crohn's disease, rheumatoid arthritis, chemotherapy, hysterectomy and intake of medication (antidepressants, steroids, hormone replacement), radiotherapy of the concerned area, breach of sterility during surgery, implant parameters, bone (quality, quantity, dehiscence or perforation), type of edentulism, antibiotics prescription, fenestration of the implant in the sinus/nasal cavity, immediate implant placement, apical lesion detection and insertion torque., Results and Conclusion: A global failure rate of 1.9% was recorded. Owing to the very few failures, no definitive conclusion concerning statistical significance can be achieved. However, a tendency for more failures was noticed for apical lesions, vicinity with natural dentition, smoking, hormone replacement, gastric problems, Crohn's disease, diabetes I and radical hysterectomy.

Aims: To review the literature on the periodontal implications of malocclusion and fixed orthodontic appliances., Methods: The PubMed database was searched for original articles on 'orthodontics and gingivitis/periodontology/plaque/ microbiology/histology', 'bracket and gingivitis/periodontology/plaque/microbiology/histology', 'crowding/spacing/overbite/overjet/open bite/crossbite traumatic occlusion and gingivitis/periodontology/plaque/microbiology/histology'. Only articles published between 1970 and 30 April 2007 were used. The search was augmented by screening the references cited in each paper for additional articles that might have been missed by the electronic search., Results/conclusions: Dental plaque is the primary cause of gingival inflammation and periodontitis. Conditions that encourage the growth and retention of dental plaque result in a localised gingivitis, which rarely progresses to periodontal disease. Only a few studies report attachment loss during orthodontic treatment. The contradictory findings on the impact of malocclusion and orthodontic appliances on periodontal health may be partly due to the selection of materials and differences in the research methods employed.

Aim: To compare undisturbed plaque formation on teeth bonded with different types of orthodontic brackets with non-bonded control teeth, via a de novo plaque growth experiment over a 7-day period., Material and Methods: A randomized controlled trial with split-mouth design was set up enroling 16 dental students. Within each subject sites with Speed(S) and GAC(G), brackets and control sites were followed. Clinical periodontal parameters were recorded at baseline, on days 3 and 7. Microbiological samples were taken from the brackets and the teeth on days 3 and 7., Results: Both anaerobe and aerobe colony-forming units (CFU) were significantly higher in S-sites than in G-sites (p=0.0002, p=0.02). The shift from aerobic to anaerobic species was observed earlier in S-sites than in G-sites. The aerobe/anaerobe CFU ratio was significantly lower in S-sites than in G-sites (p=0.01). On day 3, the crevicular fluid flow was significantly higher in S-sites than in control sites (p=0.01). On day 7, S-sites and G-sites showed a significantly higher crevicular flow than control sites (both p<0.0001). More hypertrophy was seen in S- than in G- and control sites (p=0.05). No significant differences for bleeding on probing were observed., Conclusion: Bracket design can have a significant impact on bacterial load and on periodontal parameters.

Background: From an ecological viewpoint, the oral cavity, in fact the oro-pharynx, is an 'open growth system'. It undergoes an uninterrupted introduction and removal of both microorganisms and nutrients. In order to survive within the oro-pharyngeal area, bacteria need to adhere either to the soft or hard tissues in order to resist shear forces. The fast turn-over of the oral lining epithelia (shedding 3 x/day) is an efficient defence mechanism as it prevents the accumulation of large masses of microorganisms. Teeth, dentures, or endosseous implants, however, providing non-shedding surfaces, allow the formation of thick biofilms. In general, the established biofilm maintains an equilibrium with the host. An uncontrolled accumulation and/or metabolism of bacteria on the hard surfaces forms, however, the primary cause of dental caries, gingivitis, periodontitis, peri-implantitis, and stomatitis., Objectives: This systematic review aimed to evaluate critically the impact of surface characteristics (free energy, roughness, chemistry) on the de novo biofilm formation, especially in the supragingival and to a lesser extent in the subgingival areas., Methods: An electronic Medline search (from 1966 until July 2005) was conducted applying the following search items: 'biofilm formation and dental/oral implants/surface characteristics', 'surface characteristics and implants', 'biofilm formation and oral', 'plaque/biofilm and roughness', 'plaque/biofilm and surface free energy', and 'plaque formation and implants'. Only clinical studies within the oro-pharyngeal area were included., Results: From a series of split-mouth studies, it could be concluded that both an increase in surface roughness above the R(a) threshold of 0.2 microm and/or of the surface-free energy facilitates biofilm formation on restorative materials. When both surface characteristics interact with each other, surface roughness was found to be predominant. The biofilm formation is also influenced by the type (chemical composition) of biomaterial or the type of coating. Direct comparisons in biofilm formation on different transmucosal implant surfaces are scars., Conclusions: Extrapolation of data from studies on different restorative materials seems to indicate that transmucosal implant surfaces with a higher surface roughness/surface free energy facilitate biofilm formation.

Objectives: The beneficial effects of the one-stage, full-mouth disinfection remain controversial in the scientific literature. This might be due to the fact that an entire mouth disinfection with the use of antiseptics has been confused with a full-mouth scaling and root planing. This parallel, single blind RCT study aimed to compare several full-mouth treatment strategies with each other., Material and Methods: Seventy-one patients with moderate periodontitis were randomly allocated to one of the following treatment strategies: scaling and root planing, quadrant by quadrant, at two-week intervals (negative control, NC), full-mouth scaling and root planing within 2 consecutive days (FRP), or three one-stage, full-mouth disinfection (FM) protocols within 2 consecutive days applying antiseptics to all intra-oral niches for periopathogens using as antiseptics: chlorhexidine (FMCHX) for 2 months, amine fluoride/stannous fluoride for 2 months (FMF), or chlorhexidine for 2 months followed by amine fluoride/stannous fluoride for another 6 months (FMCHX+F). At baseline and after 2, 4, and 8 a series of periodontal parameters were recorded., Results: All treatment strategies resulted in significant (p<0.05) improvements of all clinical parameters over the entire duration of the study. Inter-treatment differences were often encountered. The NC group nearly always showed significant smaller improvements than the two CHX groups. The differences between the FRP or FM groups, and the two CHX groups only sporadically reached a statistical significance., Conclusion: These observations indicate that the benefits of the "OSFMD" protocol are partially due to the use of the antiseptics and partially to the completion of the therapy in a short time.

Background: Since smoking is an established risk factor for the development of periodontitis, the present study investigated whether nicotine and cotinine can make epithelial cells more prone to colonization by periodontopathogens., Methods: Primary epithelial cell mono-layers were inoculated with nicotine and cotinine prior to adhesion experiments with Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis. The number of bacteria associated with cells inoculated or not with nicotine or cotinine were assessed by an indirect culture viability assay. The same experimental set-up was used for assessing HeLa cells exposed to cigarette smoke extract (CSE)., Results: Primary epithelial cells inoculated with concentrations of nicotine and cotinine, found in smokers and non smokers, did not show significant differences (P>0.05) in colonization susceptibility to A. actinomycetemcomitans. When these concentrations were increased to 1 mg/ml, a significant (P<0.05) and species-specific effect of the colonization susceptibility of epithelial cells was observed: It increased for A. actinomycetemcomitans, while it decreased for P. gingivalis. For both species the effects were more pronounced for nicotine, although this was not statistically significant. The change in colonization susceptibility did not result from alterations of the bacterial viability due to nicotine or cotinine. Treatment of HeLa cells with CSE also led to a species-specific variation in colonization tendency; i.e., increased for A. actinomycetemcomitans (P<0.05), but not for P. gingivalis., Conclusions: The susceptibility of epithelial cells to become colonized by either A. actinomycetemcomitans or P. gingivalis could be altered by nicotine, cotinine, or CSE in a time-dependent, species-specific manner. Whether these findings that support the hypothesis of an increased patient susceptibility for bacterial adhesion to epithelial cells in smokers are clinically relevant remains to be proven., (J Periodontol 2005;76:1315-1322.)