Introduction:Periodontitis, a chronic inflammatory disease affecting the periodontium, is primarily driven by dysbiosis of the oral microbiome with Porphyromonas gingivalis as a keystone pathogen. Current therapeutic approaches rely on mechanical debridement and antimicrobials, which face limitations including antibiotic resistance and microbiome disruption. Pathoblockers represent a novel therapeutic strategy that selectively targets virulence factors without bactericidal effects, potentially reducing resistance development while preserving beneficial microbiota. Here, we describe the characterization of S-0636, a novel reversible inhibitor of zinc-dependent glutaminyl cyclase (PgQC), as a compound to selectively inhibit the bacterial virulence of P. gingivalis. Methods:The compound's effects were assessed through enzymatic assays, bacterial growth studies, virulence factor activity measurements (gingipain activity, hemagglutination, keratinocyte invasion), selectivity testing against commensal oral bacteria, resistance development analysis over 50 passages, and cytotoxicity evaluation in human cell lines. Results:S-0636 demonstrated potent PgQC inhibition with a Ki value of 0.014 μM and has successfully reduced the intracellular PgQC activity by 50% at 8 μM and had no bactericidal effects. Treatment of P. gingivalis with S-0636 significantly decreased gingipain activity, impaired hemagglutination capacity, and reduced keratinocyte invasion by 76% at 62.5 μM. The compound showed high selectivity, with no growth inhibition of ten tested oral commensal species at concentrations up to 0.25 mM. Importantly, no resistance development was observed after 50 bacterial passages, and cytotoxicity remained minimal in human cell lines with >80% viability at 0.5 mM. Discussion:In previous studies, PgQC was suggested as an enzyme responsible for pGlu-modification and stabilization of bacterial virulence factors. The current study now validates PgQC as an attractive target for pathoblocker development, demonstrating that S-0636 effectively attenuates P. gingivalis pathogenicity through selective virulence factor inhibition while preserving bacterial viability and oral microbiome integrity. The absence of resistance development and low cytotoxicity profile support the potential clinical translation of this approach for periodontal disease management, representing a promising alternative to conventional antimicrobial therapies.

Abstract Background Adjunctive antimicrobials may improve the outcome of subgingival instrumentation, but due to the lack of evidence no antimicrobial agent is recommended for subgingival re-instrumentation (SRI). The aim of this study was to clinically, immunologically and microbiologically evaluate the potential additional effects of amino-acid sodium hypochlorite (AA-NaOCl) and cross-linked hyaluronic acid (xHA) to SRI at 3 and 6 months. Methods At the time point of reevaluation during systematic periodontal therapy, eligible patients were allocated to either control group receiving SRI of residual pockets, or test group with the adjunctive AA-NaOCl and xHA. Per patient 2 study sites were selected and clinical periodontal parameters (PD, CAL, BOP, and pocket closure), immunological biomarkers and 8 major periopathobionts were analyzed at baseline, after 3 and 6 months. Detection of IL-1β and MMP-8 was carried out using ELISA, the abundance of the periopathobionts by qPCR. Results Improvements in the clinical parameters were demonstrated in all 42 included patients. In the test group an additional PD reduction by 0.50 mm (1.38, 95% CI range: 1.11–1.65 vs. 0.88, 95% CI range: 0.62–1.14; p = 0.008) and CAL gain by 0.57 mm (1.07, 95% CI range: 0.70–1.44 vs. 0.50, 95% CI range: 0.24–0.76; p = 0.017) was found compared to the control group. The percentage of residual pockets decreased by 88.1% (n = 37) in the test, and 38.1% (n = 16) in the control group. There was no significant change in the immunological parameters. The abundance of 5 periopathobionts significantly decreased in the test group. Conclusions The adjunctive application of AA-NaOCl and xHA significantly improved the clinical and microbiological outcome 3 and 6 months after SRI. Trial registration This trial was registered in the German Clinical Trials Register (ID: DRKS00017415 at 03/06/2019).

BACKGROUND:Interest in antimicrobial surfaces for dental devices, such as aligners and brackets, is growing. These surfaces are designed to retard biofilm formation. One approach is to load essential oils (EOs) into the material. The focus of this study was the antibacterial, anti-biofilm, and anti-inflammatory activities of an EO solution. METHODS:The EO solution contained cinnamaldehyde, methyl salicylate, eucalyptol, limonene, and trans-anethole dissolved in distilled water (dH2O) with polyglycerol-4-laurate/sabacate (basic solution). The positive control was 0.2% chlorhexidine digluconate (CHX). The antibacterial activity of the EO and the basic solution was tested against selected oral bacteria. Multispecies biofilms were formed on specimens of a cellulose-based (test) material loaded with the EO solution or the basic solution, and on a polyurethane-based (reference) material loaded with CHX. The level of IL-8 released from gingival fibroblasts (GF) exposed to the solutions was measured. RESULTS:The EO solution clearly inhibited bacterial growth. However, the basic solution also acted as a growth inhibitor at higher concentrations. The EO solution reduced the metabolic activity of the formed biofilm. In addition, the basic solution decreased biofilm mass and colony-forming unit counts. The basic solution was not inferior to CHX on the reference material. However, only the basic solution, not the EO solution, suppressed the release of IL-8 from GF when stimulated with bacteria. CONCLUSION:Applying essential oils (EOs) to surfaces may be an effective way to inhibit biofilm formation. The basic solution, which is polyglyceryl-laurate-based, exhibits anti-biofilm and anti-inflammatory properties. Further in vitro research should aim to gain a deeper understanding of the solubilizer's mechanisms and optimize the composition of the added essential oils before testing in clinical trials.

Ghrelin signaling, mediated by the growth hormone secretagogue receptor (GHS-R1a), has emerged as an important regulator of inflammation and bone metabolism. This study investigated GHS-R1a regulation in periodontal tissues exposed to experimental periodontitis (EP), orthodontic tooth movement (OTM), or both. Human periodontal fibroblasts were stimulated with Fusobacterium nucleatum, static tensile strain, or their combination, and GHS-R1a expression was evaluated by RT-qPCR. In vivo experiments were conducted in rats subjected to EP, OTM, or combined treatment. Gingival GHS-R1a expression was assessed by RT-qPCR and immunohistochemistry, while alveolar bone loss was quantified histometrically. Combined bacterial and mechanical stimulation markedly increased GHS-R1a expression in periodontal fibroblasts, whereas either stimulus alone produced minimal changes. Similarly, combined EP and OTM induced a pronounced early increase in gingival GHS-R1a gene and protein expression, which declined over time. Animals exposed to both conditions also exhibited significantly greater alveolar bone loss. These findings demonstrate that periodontal inflammation and orthodontic loading dynamically regulate GHS-R1a, with early upregulation followed by attenuation during prolonged inflammation. The ghrelin/GHS-R1a system may therefore contribute to the periodontal response to concurrent inflammatory and biomechanical stimuli and participate in maintaining tissue homeostasis under inflammatory stress.

PURPOSE:To evaluate the surface roughness, hydrophobicity, and Candida albicans biofilm formation of three denture base materials, including two computer-aided design and computer-aided manufacturing (CAD-CAM) polymethylmethacrylate (PMMA) resins and one conventional heat-polymerized PMMA, before and after thermocycling (TC). MATERIALS AND METHODS:Thirty disk-shaped specimens (Ø10 × 1.5 mm) were fabricated and assigned to three groups (n = 10 each): (1) nanographene-reinforced CAD-CAM PMMA (GDM, trace graphene content <0.05 wt%), (2) pre-polymerized CAD-CAM PMMA (MDM; nanoparticle-free control), and (3) conventional heat-polymerized PMMA (CDM; nanoparticle-free control). Specimens underwent 10,000 thermal cycles in artificial saliva, followed by repeated measurements. Surface roughness was measured before polishing, before TC (after polishing), and after TC using a noncontact optical profilometer to establish baseline surface conditions and quantify finishing- and aging-related changes. Hydrophobicity was assessed before TC (after polishing) and after TC via water contact angle analysis. C. albicans biofilm formation was evaluated before TC (after polishing) and after TC using a 48-h incubation model followed by colony-forming unit quantification. The data were analyzed using a one-way ANOVA followed by Tukey's post hoc test for multiple comparisons. Additionally, paired t-tests were conducted to evaluate changes before and after TC (α = 0.05). RESULTS:Surface roughness differed significantly before polishing and after TC (p < 0.001), but not before TC (after polishing) (p = 0.129). CDM had the highest roughness; GDM showed the lowest after TC (p < 0.001). Water contact angle did not differ significantly among materials (p ≥ 0.136). GDM initially showed higher C. albicans biofilm than CDM (p = 0.009), but levels decreased after TC (p < 0.001), with no differences thereafter. Biofilm formation after TC correlated positively with contact angle (r = 0.478) and negatively with roughness (r = -0.401). CONCLUSION:Surface polishing reduced the roughness of all tested materials, with GDM exhibiting the lowest roughness. The incorporation of nanographene in a pre-polymerized PMMA denture base reduced roughness and C. albicans biofilm formation.

This in vitro study aimed to evaluate the effects of bovine milk and plant-based alternatives on oral microorganisms and multispecies biofilms, in part in interaction with monocytic cells. Test substances (all without added sugar) included bovine milk, plant-based oat drink, plant-based almond drink, and plant-based soy drink. Growth of Streptococcus gordonii, S. mutans (here also with 7.5% sucrose), and Porphyromonas gingivalis with 2.5% and 10% test substances was measured. Sediment of P. gingivalis cultures with 10% test substance at 24 h was assayed for Arg-gingipain activity. Further, two defined multi-species biofilms (caries and periodontal) were cultured on surfaces coated with the test substances (final concentration 10%) for 4 h and 24 h or 48 h, before biofilms were analyzed. Monocytic cells were added to periodontal biofilm, and thereafter, interleukin (IL)-1β and IL-10 expression was determined. The growth of S. gordonii was slightly promoted by bovine milk and by three of the four plant-based milk alternatives tested. In media with 5% sucrose and test substances, the S. mutans colony forming units (CFU) counts were lower at 6 h with the lowest counts after incubation with 2.5% bovine milk. Almond drink reduced the CFU counts in a formed cariogenic biofilm; bovine milk and soy drink reduced both mass and metabolic activity. The arginine-specific amidolytic activity of P. gingivalis was blocked with 10% almond drink. Oat drink and bovine milk decreased both CFU counts and metabolic activity of the formed periodontal biofilm. Independent of biofilm presence, soy drink increased the release of IL-10. These in-vitro results may support the available epidemiologic data on the inverse association of the intake of milk with caries and periodontitis. Plant-based drinks should be further investigated. Of special interest might be the inhibition of gingipain activity by almond drink as well as the immune-modulatory effects of soy drink.

OBJECTIVES:In vitro models provide valuable insights into treatment options and their effectiveness prior to and alongside clinical evaluation. Such models should be standardized, reproducible, and closely reflect the clinical situation. This study aimed to investigate the removal of subgingival biofilm and calculus by instrumentation, which is vital in the successful treatment of periodontitis. The approach was to (i) develop an in vitro model based on biofilm and calculus formation and (ii) assess it by hand and ultrasonic instrumentation, while (iii) measuring the forces applied in an innovative periodontal defect model. MATERIALS AND METHODS:A multi-species mixture consisting of 11 bacterial strains was used to form an initial calculus over 14 days. Inserts carrying human dentin specimens, either with biofilm or with a combination of biofilm and calculus, were placed in a periodontal pocket model equipped with a multi-axis force sensor, followed by treatment with hand or ultrasonic instrumentation. Instrumentation forces were recorded, and the remaining biofilm or biofilm/calculus was analyzed for bacterial colony-forming unit (cfu) counts and calcium levels after instrumentation. RESULTS:The results revealed that the cfu counts and calcium levels in the biofilm/calculus group were higher compared to the respective biofilm controls. Ultrasonic instrumentation was more effective than hand instrumentation in reducing cfu counts in both the biofilm and biofilm/calculus groups. Furthermore, both hand and ultrasonic instrumentation reduced calcium levels in the biofilm/calculus groups. The peak forces Fy in the hand instrumentation groups were significantly higher in both the biofilm and biofilm/calculus groups compared to the respective ultrasonic groups. CONCLUSIONS:The model enabled an initial reproducible calculus formation and evaluation of different instrumentation modalities, including the forces applied. The results favored the ultrasonic instrumentation due to its superior removal of biofilm and calculus and lower lateral forces. The presented biofilm/calculus model offers a new in vitro approach for comparing different instrumentation modalities.

Periodontitis is a common inflammatory disease of the periodontal tissue caused by dysbiotic microbiota. An effective, preventive, and therapeutic method is the mechanical removal of dental biofilms and calculus using manual or powered scalers. Ultrasonic scalers are becoming increasingly popular, but regulating the applied force can be challenging. Excessive force may damage the tooth surface and reduce scaler efficacy. This work presents a novel force measurement system integrated into an ultrasonic dental scaler. Three sensor concepts were developed and evaluated based on the magnetic Hall effect, barometric pressure, and strain gauges. These sensors detect elastic deformations in the micrometre range to measure the magnitude and direction of the applied force. The Hall effect sensor proved the most reliable, measuring forces with an accuracy of up to ± 0.1 N. A custom test bench was developed for calibration and testing under simulated clinical conditions. In vitro testing confirmed the feasibility of the Hall effect concept. Overall, this research establishes a foundation for real-time force feedback in dental training.

Background/Objectives: Periodontal disease involves chronic immunoinflammatory processes and microbial dysbiosis, making phytochemicals with anti-inflammatory properties potential therapeutic agents. This study aimed to assess the modulatory effects of yellow passion fruit bagasse extract (PFBE) on periodontal cells under microbial condition. Methods: A human periodontal ligament (PDL) cell line was exposed to F. nucleatum ATCC 25586 to simulate a microbial environment in vitro in the presence and absence of PFBE containing three different concentrations (0.25, 0.50, and 1.00 µg/mL) of piceatannol. Pro-inflammatory markers (TNF-α, IL-8, CCL2), the antioxidant enzyme SOD2, and the protease marker MMP-1 were analyzed by real-time PCR. Protein levels were assessed via ELISA and NF-κB nuclear translocation by immunofluorescence. Cell viability was investigated using live/dead and alamarBlue assays, and in vitro wound healing was evaluated by an automated scratch assay. Results: PDL cells exposed to F. nucleatum significantly increased the gene and protein expression of all inflammatory markers. The stimulatory effects of F. nucleatum were significantly reduced when PDL cells were simultaneously exposed to PFBE. F. nucleatum triggered the NF-κB nuclear translocation while PFBE abrogated the F. nucleatum-stimulated NF-κB nuclear translocation at 60 min. Viability assays demonstrated that neither PFBE nor F. nucleatum were toxic or significantly affected PDL cell viability. In vitro wound closure was improved by the addition of PFBE to F. nucleatum. Conclusions: PFBE exhibited anti-inflammatory and anti-proteolytic effects while improving in vitro wound healing, suggesting a potential modulatory role of PFBE in periodontal disease prevention and treatment.

Objectives: To evaluate and compare the plaque-reducing efficacy of sesame-based oil pulling versus distilled water in a randomized controlled, examiner-blinded parallel-group study. Materials and Methods: Forty participants with gingivitis (community periodontal index of treatment needs grade 1 or 2) were randomly assigned to either the test group (sesame-based oil) or the control group (distilled water). Participants were instructed to perform oil pulling daily in the morning for 15 min over an eight-week period. The Rustogi Modified Navy Plaque Index (RMNPI) and gingival bleeding index (GBI) were evaluated at the baseline, as well as after four and eight weeks. Additionally, biofilm samples were collected for microbiological analysis. Results: The RMNPI was statistically significantly reduced after eight weeks of pulling with sesame-based oil (p < 0.001), as well as with distilled water (p < 0.001), without a significant difference between the groups. The GBI was statistically significantly reduced after eight weeks of pulling with sesame-based oil (p < 0.002), as well as with distilled water (p < 0.002), without a significant difference between the groups. No significant microbiological changes were detected in biofilm samples. Conclusions: Both plaque and gingival indices significantly decreased with oil pulling after eight weeks of intervention. Preclinical studies are necessary to clarify the mechanism of plaque reduction by oil pulling.

PURPOSE:To investigate the antibacterial and anti-biofilm effects of two Manuka honey toothpaste formulations containing propolis (Manuka prop) or fluoride (Manuka F), in comparison with the toothpaste base (TP con) and a commercial toothpaste (TP com), on oral bacteria and biofilm. MATERIALS AND METHODS:The minimum inhibitory concentration (MIC) of the formulations and controls were tested against five oral bacterial species. Both the effect on a multispecies dental biofilm precultured for 3.5 days as well as the inhibition of de-novo biofilm formation up to 24 h were investigated. Test substances at concentrations of 20%, 10% and 5% were applied to preformed biofilm for 1 min. The reduction in colony-forming units (cfu), metabolic activity, and biofilm mass were determined. Similarly, the test substances were applied to surfaces for 30 min before bacteria and media were added. The reduction of a tetrazolium dye (MTT assay) was used to assess cytotoxicity on gingival fibroblasts. RESULTS:The MIC values of all toothpaste formulations including TP con were very low with the highest MIC of 0.04%. In precultured biofilms, both the number of colony forming units (cfu) and metabolic activity decreased following addition of any toothpaste. The greatest reductions of cfu were found after addition of 20% TP com (by about 6 log10) and after 20% Manuka prop (by about 2.3 log10). However, the biofilm mass was not reduced. Coating the surface with toothpaste formulation, the cfu in the newly formed biofilm decreased in a concentration-dependent manner, with TP com being most active. Both 20% of Manuka prop and Manuka F reduced the cfu counts more than the TP con at 24 h. The toothpaste formulations affected the viability of gingival fibroblasts in a concentration-dependent manner, with no differences observed among the formulations. CONCLUSION:The Manuka-honey containing toothpastes might be an alternative to toothpaste containing conventional chemical agents. Further research is needed to clinically examine the effect on caries and gingivitis prevention.

To investigate in vitro the influence of instrumentation methods on the bacterial colonization of root dentine and pulpal cell behaviour seeded into the pulp cavum. Extracted teeth underwent root canal treatment with sealing of apices. The teeth were subjected to periodontal instrumentation using manual, ultrasonic scalers, air polishing, or left untreated. The root surfaces were then incubated with a mixture of six bacterial species for 2 h, 24 h and 10 weeks, before dentine samples were taken and analyzed for bacterial colony forming units (cfu) counts. In an additional series, pulpal cells were seeded into the reopened pulp chambers after 10 weeks of incubation with the bacterial mixture and analysed for interleukin (IL)-8 and matrix metalloprotease (MMP)-3 expression. After 2 and 24 h of incubation, instrumented dentine samples contained fewer bacteria than the controls (median (log10 cfu): 5.73 vs. 5.92; 7.71 vs. 8.01 (p = 0.007; p = 0.017)). At 24 h, among the instrumentation groups the highest cfu counts were observed in the ultrasonic group (p = 0.012 vs. manual scaler group; p = 0.002 vs. air polishing group). After 10 weeks, the number of viable bacteria (cfu) decreased in all groups with no difference between any group. Pulpal cells seeded in teeth, with or without prior instrumentation, but exposed to the bacterial mixture for 10 weeks, released higher levels of IL-8 and MMP-3 compared to those in uncontaminated and untreated controls. Instrumentation initially inhibits bacterial colonisation. Prolonged exposure of the outer root surface to bacteria may increase the inflammatory response of pulpal cells. Regular removal of bacteria from the root surface is supported by these in vitro data.

Periodontal disease affects over 1 billion people globally. This study investigated how periodontitis affects the protein profile of the periodontal ligament (PDL) in rats. Eight Holtzman rats were divided into control and experimental periodontitis groups. The PDL was isolated using laser capture microdissection and protein extracts were analyzed by mass spectrometry. Data analysis utilized specialized software, and Gene Ontology enrichment analysis identified significant protein functions. The data are available via ProteomeXchange with identifier PXD055817. Proteins such as SerpinB1, C5, and Lgals3 were validated through immunohistochemistry, and their gene expression was examined in an in vitro human PDL cell line. This study identified 1326 proteins, with 156 unique to the control group, 294 unique to the periodontitis group, and 876 common to both groups. Enrichment analysis revealed that proteins associated with the regulation of enzyme activity and RNA binding were significantly represented in the periodontitis group. There were increased levels of SerpinB1, C5, and Lgals3 in the periodontitis group based on proteomic and immunohistochemical analyses. Furthermore, these targets showed increased gene expression in stimulated human PDL cells. This study provides insights into the periodontitis-related alterations in the protein composition of the PDL and PDL cells, identifying both novel and previously known disease-associated proteins. SIGNIFICANCE: The periodontal ligament plays a crucial role in oral functions by providing structural support to the tooth. Due to the presence of undifferentiated mesenchymal cells, research into its regenerative capacity is ongoing. Pathological conditions can affect these functions and protein composition. Currently, there is a lack of comprehensive research specifically focusing on evaluating the periodontal ligament in both healthy and diseased states. This pioneering study screened for protein alterations and the mechanisms related to periodontitis. The possibility of using proteomic analysis to evaluate the protein alterations that occur in periodontitis, a disease with a high global incidence, could provide therapeutic targets and new biomarkers for future clinical studies.

IntroductionModifying bacterial virulence could be an interesting alternative to antibiotics. The study aimed to examine the effects of an inhibitor targeting bacterial glutaminyl cyclase [which is selectively present in Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), and Prevotella intermedia (Pi)] on various multispecies biofilms.MethodsTwo multi-species biofilms—one containing four species (including Tf) and another with 12 species (including Tf, Pg, and Pi)—were cultured in the presence of 31.25–500 µM of a [4,5-c]pyridine-based inhibitor. After 24 h, bacterial counts, biofilm biomass, metabolic activity, and, when Pg was included, Arg-gingipain activity were measured. Additionally, the biofilms were exposed to monocytic cells; here, the release of interleukin (IL)-1β and IL-10 was analyzed. The data were analyzed using a one-way analysis of variance (ANOVA) with a post-hoc comparison performed using the Bonferroni correction.Results and DiscussionIn all biofilms, total bacterial counts and those of Pg and Tf remained unaffected by the inhibitor. In the 12-species biofilm, both biomass and total metabolic activity decreased at high inhibitor concentrations (500 µM to 75.2 ± 6.5% and 87.2 ± 5.8%, respectively; each p < 0.001). The arginine-specific amidolytic activities of Rgp declined dose-dependently, down to 60.4 ± 10.2% (p < 0.001) at 500 µM of the inhibitor. Consequently, Pg colonies lost pigmentation as inhibitor concentrations increased. The inhibitor also reduced IL-1β release from monocytic cells stimulated by the 12-species biofilm. The studied [4,5-c]pyridine-based inhibitor is able to modify virulence of a multispecies biofilm. It might have the potential to be a promising approach in periodontal prevention and therapy.

STATEMENT OF PROBLEM:Different computer-aided design and computer-aided manufacturing (CAD-CAM) materials have been used to fabricate complete arch implant-supported prostheses (CAISPs), but studies comparing their surface properties and biofilm formation are limited. PURPOSE:The purpose of this in vitro study was to evaluate the water contact angle, surface roughness, and biofilm formation of CAD-CAM materials used for CAISPs and to assess the effect of hydrothermal aging. MATERIAL AND METHODS:Seventy disk-shaped specimens were fabricated (Ø5×2 mm) from titanium (Ti), 55-V anodized Ti (Ti5 55 Hz), 65-V anodized Ti (Ti5 65 Hz), cobalt chromium (Co-Cr), zirconia (Zir), polymethylmethacrylate (PMMA), and polyetheretherketone (PEEK) (n=10). The water contact angle, surface roughness, and initial biofilm formation (CFU) were measured before and after hydrothermal aging and Streptococcus gordonii growth curves were evaluated. Mixed ANOVA with corrections was used to assess the effects of hydrothermal aging and material type (α=.05). RESULTS:Before aging, Co-Cr had the highest water contact angle (P<.05), excluding PEEK (P=.114). PEEK had the highest roughness (P≤.004). The biofilms (CFU) formed on PEEK, PMMA, and Ti were higher than on Ti5 55 Hz, Ti5 65 Hz, Co-Cr, and Zir (P≤.034). After aging, Ti had the lowest water contact angle. PMMA, PEEK, and Zir had the highest roughness (P<.001). Co-Cr and Zir had more CFU counts than PEEK (P=.024; P=.049). Eluates from aged materials did not affect Streptococcus gordonii growth. CONCLUSIONS:Material type and hydrothermal aging affected surface properties and biofilm formation. Before aging, Co-Cr had the highest water contact angle (except PEEK), while, after aging, Ti had the lowest. PEEK, Zir, and PMMA showed higher roughness than metals. Biofilm formation was greater on Ti, PMMA, and PEEK before aging, but, after aging, PEEK exhibited less biofilm than Zir and Co-Cr.

Objectives To compare the plaque reducing efficacy of oil pulling with sesame oil compared to distilled water in a randomized, controlled, examiner-blinded parallel group study. Materials and methods Forty probands without advanced periodontal disease of the University Hospital for Restorative Dentistry and Periodontology, Medical University of Innsbruck (Austria) were randomized allocated to test- (sesame oil) or control group (distilled water) and asked to pull daily in the morning for eight weeks with their allotted fluid for 15 min. Rustogi Modified Navy Plaque Index (RMNPI) and gingival bleeding index were assessed at baseline and after four and eight weeks. Plaque samples underwent microbiological analysis. Results Pulling with sesame oil was significantly more effective in reducing full mouth RMNPI compared to distilled water after eight weeks (median reduction 18.98% versus 10.49%; p = 0.023), and was most pronounced in anterior, buccal, and lingual subscales. On approximal surfaces, significantly higher plaque reduction was found in the test group after four (24.07% versus 14.29%) and eight weeks (16.00% versus 5.36%) of intervention ( p < 0.05). No significant changes in gingival index and mirobiological analysis could be detected. Conclusion Plaque reduction was statistically significantly higher with oil pulling than with distilled water, however, a study bias cannot be ruled out. Further high-quality trials are needed to understand the mechanisms and effectiveness of oil pulling, to finally clarify the evidence. Clinical relevance Oil pulling may be recommended as an adjuvant to mechanical dental cleaning. Individuals with keratosis may experience adverse effects. Trial registration ClinicalTrials.gov NCT06327841.

Purpose: The COVID-19 pandemic raised the question about the extent of microbial exposure encountered by dentists during dental therapy. The purpose of this study was to quantify microbial counts on surgical masks related to duration and type of dental therapy, as well as patient oral health variables. Materials and Methods: Sterile filter papers were fixed on surgical masks used during routine daily dental therapy. Thereafter, the filter papers were pressed onto blood agar plates for 1 min, before the agar plates were incubated with 10% CO2. After 48 h, the colony forming units (CFU) were counted and microorganisms were identified. The dependence of the CFU counts on treatment and patient-related variables was analysed using linear regression. Results: Filter papers obtained from 322 dental treatments (429 masks) were included in the final analysis. On average, 5.41 +/- 9.94 CFUs were counted. While mostly oral bacteria were detected, Staphylococcus aureus was also identified on 16 masks. Linear regression, incorporating patient-related and treatment characteristics through step-wise inclusion, revealed statistical significance (p < 0.001) only with the variable "assistance during therapy". The type of dental treatment exhibited a trend, with fewer CFUs observed in caries treatment compared to periodontal or prosthodontic therapy. Furthermore, after analysing filter papers from masks used by dental assistants in 107 dental treatments, fewer CFUs were found on the masks compared to those used by dentists (p < 0.001). Conclusion: The mean number of CFUs observed consistently remained low, highlighting the efficacy of the implemented hygiene measures. Consequently, it is clinically recommended to support dental treatment with precise suction of the generated aerosols.

Besides dental caries, periodontitis and periimplant infections are the two most prevalent biofilm-associated oral diseases. Such chronic inflammation can cause destruction of the supporting gum tissue and eventually bone and tooth loss. To prevent oral pathologies, a professional routine for the removal of soft and hard bacterial deposits is recommended in supplement to daily oral hygiene. Manual instrumentation with curettes and ultrasonic scalers are used for prophylactic treatment. However, current ultrasonic instruments are limited in dimensions and operating frequencies. An innovative design for a novel dental scaler based on a planar ultrasonic transducer is introduced. The planar design allows the mass to be considerably reduced compared to a conventional Langevin transducer, resulting in a higher velocity to current ratio and thus an efficient but also sensitive scaler. The feasibility and potential of the planar scaler have already been confirmed by achieving displacement amplitudes of $> 50\ {\mu{\mathrm{m}}}$ at 28 kHz. In addition, the planar design allows for an alteration of the resonant frequency through minor geometric adjustments to the horn. The design was modified for 20 and 40 kHz to obtain information about the most advantageous operating frequency, through both electromechanical characterisation and an in vitro setup with an artificial biofilm pocket model.

Background: Periodontitis is an inflammatory condition initiated by oral bacteria and is associated with several systemic diseases. Quercetin is an anti-inflammatory and anti-bacterial poly-phenol present in various foods. The aim of this meta-analysis was the evaluation of the effects of quercetin administration in animal models of experimental periodontitis. Methods: A systematic search was performed in electronic databases using the following search terms: “periodontitis” or “periodontal disease” or “gingivitis” and “quercetin” or “cyanidanol” or “sophoretin” or “pentahydroxyflavone”. In vivo preclinical animal models of experimental periodontal disease with a measurement of alveolar bone loss were included in the analysis. The risk of bias of the included studies was assessed using the SYRCLE tool. Results: The systematic search yielded 335 results. Five studies were included, four of them qualified for a meta-analysis. The meta-analysis showed that quercetin administration decreased alveolar bone loss (τ2 = 0.31, 1.88 mm 95%CI: 1.09, 2.67) in experimental periodontal disease animal models. However, the risk of bias assessment indicated that four SYRCLE domains had a high risk of bias. Conclusions: Quercetin diminishes periodontal bone loss and prevents disease progression in animal models of experimental periodontal disease. Quercetin might facilitate periodontal tissue hemostasis by reducing senescent cells, decreasing oxidative stress via SIRT1-induced autophagy, limiting inflammation, and fostering an oral bacterial microenvironment of symbiotic microbiota associated with oral health. Future research will show whether and how the promising preclinical results can be translated into the clinical treatment of periodontal disease.

BACKGROUND:The aim of this study was to compare the clinical efficacy and the patient perception of subgingival debridement with either guided biofilm management (GBM) or conventional scaling and root planing (SRP) during supportive periodontal care (SPC). METHODS:Forty-one patients in SPC were randomly assigned to either treatment with GBM or SRP every 6 months. The primary outcome was the percentage of bleeding on probing (BoP) at 1 year. Moreover, pocket probing depths (PPD), recession, and furcation involvements were also measured. Full-mouth and specific site analyzes were performed at baseline, 6 and 12 months of SPC. Patient comfort was evaluated using a visual analogue scale (VAS) at 12 months. RESULTS:At 1 year, mean BoP percentage decreased from 12.2% to 9.0% (p = 0.191) and from 14.7% to 7.9% (p = 0.004) for the GBM and SRP groups, respectively. Furcation involved multirooted teeth but no through-and-through lesions were significantly fewer in the GBM than in the SRP group after 12 months (p = 0.015). The remaining parameters showed slight improvement in both groups without any statistically significant differences between the two groups after 1 year. Pain evaluation as patient reported outcome measures (pain evaluation) was in favor (p = 0.347) of the SRP group, while overall satisfaction was similar for both groups. Treatment time was not statistically significantly different between the two groups (p = 0.188). CONCLUSION:In well-maintained SPC patients, SRP protocols resulted in significant clinical improvements in terms of BoP; however, for the other clinical improvements, similar efficacy for both GBM and SRP was observed.