Microbial etiological agents of destructive periodontal diseases

Influence of orthodontic appliances and nitrate on the oral microbiota

In this pilot study, we investigated the bacterial changes introduced on the subgingival, tongue, and saliva microbiota during fixed orthodontic treatment, with or without daily administration of nitrate-containing beet juice for 2 weeks in 22 individuals with good general health. We followed clinical parameters in combination with microbiota changes before, after 2 weeks, and after 6 months of treatment with fixed orthodontic appliances. In accordance with variations in community composition at the sampling sites, effects to orthodontic treatment differed. Subgingival communities responded promptly to orthodontic treatment with no additional structural changes over time, whereas saliva and tongue communities were affected only after extended treatment. Periodontal pathogens such as Selenomonas sputigena were enriched in subgingival communities, whereas Streptococcus mutans was enriched in saliva. Specifically, Rothia mucilaginosa increased tremendously in relative abundance in both tongue and saliva communities. The effect of beet juice on microbial composition was significant in subgingival samples even though the differences were not mirrored in single differentially distributed genera or species. This indicates changes in the complete subgingival microbial net of interacting species. However, the prevention of Corynebacterium matruchotii enrichment by beet juice may be important for prevention of biofilm formation. Enrichment of Neisseria flavescens group bacteria and Abiotrophia and depletion of different Actinomyces and Stomatobaculum were observed on tongue communities. We conclude that subgingival microbiota are rapidly affected by fixed orthodontic appliances and can be positively influenced by regular administration of nitrate-containing juice. KEY POINTS: • The subgingival site, tongue, and saliva contain different microbiota • The microbiota react differently to orthodontic treatment and beet juice • Key genera and species affected by treatments were identified.

An overview of the microbiota of the oral cavity of humans and non-human primates with periodontal disease: Current issues and perspectives

OBJECTIVE

To provide a comprehensive summary of the available evidence on the oral microbiota of humans and non-human primates about the etiology of periodontal disease.

DESIGN

An integrative literature review was conducted on 398 clinical and observational articles published between 2010 and 2024 using searches in the MEDLINE/PubMed, Virtual Health Library, and SciELO databases. After the screening, eligibility, data extraction, and methodological quality assessment, 21 studies were selected.

RESULTS

The results, which reveal striking similarities between the pathogens involved in periodontal disease in humans and NHPs, confirm the potential of NHPs as research models and inspire further research in this area.

CONCLUSION

According to these studies, Actinomyces spp., Aggregatibacter actinomycetemcomitans, Campylobacter rectus, Capnocytophaga spp., Eubacterium spp., Filifactor alocis, Fusobacterium spp., Leptotrichia spp., Neisseria mucosa, Parvimonas micra, Porphyromonas spp., Prevotella spp., Selenomonas spp., Streptococcus spp., Treponema spp., Tannerella spp., Veillonella parvula, were the genus and/or species of bacteria found in humans. On the other hand, Aggregatibacter acinomycetemcomitans, Campylobacter rectus, Desulfobulbus spp., Dialister invisus, Eikenella corrodens, Filifactor alocis, Fusobacterium spp., Parvimonas micra, Porphyromonas spp., Prevotella spp., Staphylococcus spp., Streptococcus spp., Treponema spp., Tannerella spp., Veillonella spp., were the most reported in NHPs. No study in non-human primates reported the presence of protozoa, unlike studies in humans that reported the presence of Entamoeba gingivalis and Trichomonas tenax. However, its role in periodontal disease still needs to be elucidated, despite the strong association mainly with severe periodontal disease where protozoa are observed in injured tissues.

Oral health in adolescents: periodontal inflammatory biomarkers during orthodontic clear aligner therapy

OBJECTIVES

This prospective study aimed to evaluate periodontal inflammation in adolescents undergoing orthodontic treatment with clear aligners (Invisalign® Teen, Align Technology, San Jose, CA, USA). Key objectives included assessing the presence of 11 periodontitis-associated marker bacteria, active matrix metalloproteinase-8 concentrations in sulcular fluid, and the influence of IL-1 polymorphism genotypes on periodontal health.

MATERIALS AND METHODS

Fifty adolescent patients (13.3 ± 1.8 years) with mixed and permanent dentition participated. Gingival crevicular fluid samples were analyzed at multiple time points: before, during, and one year after aligner treatment. Periodontal health was assessed using the Gingivitis Index and the Modified Quigley-Hein Index. Genotypic analysis of IL-1 polymorphism was also performed. Statistical analyses included mixed linear models and generalized linear models to explore correlations.

RESULTS

All combinations of IL-1 polymorphism genotypes were found in the sample. No significant increase in periodontal inflammation or aMMP-8 concentrations was observed over the treatment period. Marker bacteria from the red and orange-associated complexes remained at low levels, while significant changes occurred in the orange and green complexes, particularly Capnocytophaga spp. (p = 0.0042) and Fusobacterium spp. (p = 0.0365). GI correlated significantly with aMMP-8 levels (p = 0.0017), but no genotype effect on GI was observed. MQH showed associations with pathogens from the orange and green complexes, including Capnocytophaga spp. and Fusobacterium spp.

CONCLUSIONS

Clear aligner treatment in adolescents, including those with an unfavorable genotype, does not increase periodontal inflammation when accompanied by good oral hygiene.

CLINICAL RELEVANCE

Regular periodontal monitoring and hygiene reinforcement is important during orthodontic treatment, especially in adolescent patients.

Subgingival 0.75% boric acid vs 1% povidone-iodine adjunctive to subgingival instrumentation in stage II and III periodontitis-A double-blind randomized clinical trial

PURPOSE

To compare the effects of subgingival irrigation with 0.75% boric acid (BA) and 1% povidone-iodine (PVP-I) as an adjunct to scaling and root planing (SRP) on clinical and microbiologic parameters in the management of patients with periodontitis after a 12-month follow-up.

METHODS

Sixty systemically healthy individuals diagnosed with periodontitis were included in this double-blind randomised clinical trial. The patients were randomly allocated to treatment groups: (1) SRP plus 0.75% BA and (2) SRP plus 1% PVP-I. Whole-mouth periodontals were clinically examined, and the counts of bacteria including Aggregatibacter actinomycetemcomitans (Aa), Fusobacterium nucleatum (Fn), Porphyromonas gingivalis (Pg), Treponema denticola (Td), Tannerella forsythia (Tf), Solobacterium moorei (Sm) and Streptococcus salivarius (Ss) were tested by real-time polymerase chain reaction (PCR).

RESULTS

All periodontal parameters and the counts of Aa, Fn, Pg, Td, Tf, Sm and Ss in both groups showed statistically significant reductions at T3, T6 and T12 compared to T0. Whole-mouth or moderate or severe PD and CAL improvements were significantly found in the 0.75% BA group compared to the 1% PVP-I group at T3, T6 and T12. The reduction in Aa or Fn and the reduction in Ss were significantly higher in the 0.75% BA group at T6 and T12 than in the 1% PVP-I group.

CONCLUSION

This study shows that subgingival irrigation with 0.75% BA may be an alternative to 1% PVP-I because it promotes greater PD reductions and CAL gain, particularly up to 12 months after treatment.

The Microbial Diversity and Biofilm Characteristics of d-PTFE Membranes Used for Socket Preservation: A Randomized Controlled Clinical Trial

BACKGROUND

Understanding microbial colonization on different membranes is critical for guided bone regeneration procedures such as socket preservation, as biofilm formation may affect healing and clinical outcomes. This randomized controlled clinical trial (RCT) investigates, for the first time, the microbiome of two different high-density polytetrafluoroethylene (d-PTFE) membranes that are used in socket preservation on a highly molecular level and in vivo.

METHODS

This RCT enrolled 39 participants, with a total of 48 extraction sites, requiring subsequent implant placement. Sites were assigned to two groups, each receiving socket grafting with a composite bone graft (50% autogenous bone, 50% bovine xenograft) and covered by either a permamem® (group P) or a Cytoplast™ (group C). The membranes were removed after four weeks and analyzed using scanning electron microscopy (SEM) for bacterial adherence, qPCR for bacterial species quantification, and next-generation sequencing (NGS) for microbial diversity and composition assessment.

RESULTS

The four-week healing period was uneventful in both groups. The SEM analysis revealed multispecies biofilms on both membranes, with membranes from group C showing a denser extracellular matrix compared with membranes from group P. The qPCR analysis indicated a higher overall bacterial load on group C membranes. The NGS demonstrated significantly higher alpha diversity on group C membranes, while beta diversity indicated comparable microbiota compositions between the groups.

CONCLUSION

This study highlights the distinct microbial profiles of two d-PTFE membranes during the four-week socket preservation period. Therefore, the membrane type and design do, indeed, influence the biofilm composition and microbial diversity. These findings may have implications for healing outcomes and the risk of infection in the dental implant bed and should therefore be further explored.

Evaluation of leukocyte-platelet rich fibrin as an antibiotic slow-release biological device in the treatment of moderate periodontitis: a randomized controlled clinical trial

BACKGROUND

Periodontitis is a chronic inflammatory disease caused by the accumulation of biofilm. Antimicrobials have been used as adjuncts to non-surgical periodontal therapy. However, systemic antibiotics often require large dosages to achieve suitable concentrations at the disease site. Leukocyte platelet-rich fibrin (L-PRF) is a promising bio-material, with antimicrobial, anti-inflammatory, and wound-healing enhancement effects. This study aimed to evaluate the efficacy of L-PRF as a locally sustained released device for metronidazole antimicrobial.

METHODS

Twenty-four patients with eighty periodontal pockets had moderate periodontitis with attachment loss of 3-4 mm, and probing depth ≤ 5, which was equally divided into two groups: Group (I) underwent scaling and root planing with intra-pocket application of L-PRF loaded with Metronidazole, while Group (II) was treated by scaling and root planing with intra-pocket application of L-PRF alone. Microbiological measurements were taken at baseline and after one month to analyze the relative count of Porphyromonas gingivalis (P. gingivalis) using real time PCR. Clinical parameters were measured at baseline and after 1, 3, and 6 months. These parameters included probing depth (PD), clinical attachment loss (CAL), plaque index (PI), modified gingival index (MGI), and bleeding index (BI).

RESULTS

Microbiological and clinical findings revealed that both treatment methods resulted in a reduction in P. gingivalis counts, in addition to improvements in the clinical parameters: PD reduction, CAL gain, PI reduction, BI decrease and MGI reduction compared to baseline. However, L-PRF-metronidazole group showed superior results in the studied parameters over the study period. Nonetheless, there was no statistically significant improvement. (p < .001).

CONCLUSION

The intra-pocket application of both L-PRF loaded with Metronidazole and L-PRF alone contributed to the successful treatment of moderate periodontitis.

TRIAL REGISTRATION

NCT06153706 ( http://www.clinical-trials.gov/ ); 1/12/2023, retrospective registration.

Role of DDR1 in Regulating MMPs in External Root Resorption

Human periodontal ligament cells (hPDLCs) express matrix metalloproteinases (MMPs), a group of enzymes responsible for the destruction of most extracellular matrix proteins in dental tissues, especially MMP-1, MMP-2, and MMP-13. Exploring the regulatory mechanism of MMPs is crucial for understanding external root resorption (ERR), one of the most severe complications, along with substantial loss of dental tissue, induced by trauma, pulpal infection, tooth bleaching, and orthodontic treatment, etc. Discoidin domain receptor 1 (DDR1), a cell surface receptor binding to collagen, has the potential to regulate the expression of MMP-1, MMP-2, and MMP-13, but the mechanism remains unclear. Thus, the present study aimed to investigate the connection and underlying mechanism between MMP-1, MMP-2, MMP-13, and DDR1 in hPDLCs. Our post-replantation ERR model revealed that Mmp-1, Mmp-2, Mmp-13, and Ddr1 all increased in the sites of ERR. hPDLCs with DDR1 knockdown exhibited a substantial reduction in MMP-1, MMP-2, and MMP-13 expression. To further confirm the underlying mechanism, we conducted further in vitro experiments, including RNA sequencing, RNA interference, RT-qPCR, Western blotting, and ELISA. Based on our results, MMP-1 was positively regulated by the Smad2/3 and MEK-ERK1/2 pathways and negatively regulated by the PI3K-Akt pathway through CCN2. MMP-2 and MMP-13 were positively regulated by the Smad2/3 pathway. MMP-13 was positively regulated by the MEK-ERK1/2 and PI3K/Akt signaling pathways. Collectively, DDR1 is a potent regulator of MMP-1, MMP-2, and MMP-13 expression through the Smad2/3, MEK-ERK1/2, and PI3K/Akt signaling pathways. Clarifying the significance and underlying mechanism by which DDR1 is involved in ERR might bring the chances to hinder the pathogenic process of ERR, hence reducing its incidence rate.

Evaluation of antimicrobial activity of platelet-rich fibrin and titanium platelet-rich fibrin with and without incorporation of antibiotics on Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans: An in vitro study

Background

Infection control is of paramount importance after any periodontal therapy to achieve proper wound healing and regeneration of periodontal tissues. Clinicians continuously strive to provide procedures and/or materials that allow for enhanced and rapid wound healing. The regenerative potential of platelet concentrates like platelet-rich fibrin (PRF) has been explored for their anti-inflammatory action and liberation of growth factors; however, research is lacking on the antibacterial properties of platelet-rich gels. The present in vitro study was done to assess the antimicrobial activity of PRF and titanium PRF (T-PRF) alone or with antibiotics on periodontal pathogens.

Materials and Methods

Thirty-three individuals who were willing to donate blood (12 ml) were included in the study. Amoxicillin (AMOX) + metronidazole (METRO) combination or clindamycin (CLINDA) was incorporated into the blood drawn, and this blood was subjected to centrifugation so as to obtain T-PRF and PRF with antibiotics. The antibacterial activity of all the groups was tested on both bacteria that were cultured in their respective media for up to a 4-day period. The data were subjected to independent t-test, Tukey post hoc test, repeated analysis of variance (ANOVA), and ANOVA.

Results

All individual parameters were compared for antimicrobial activity on both bacteria on all 4 days. A highly statistical difference (P = 0.0001) was observed in all the groups, with the highest inhibition zone produced by PRF-CLINDA, followed by T-PRF-CLINDA. Antimicrobial activity was evident for the observed 4-day period, which declined from day 1 to day 4.

Conclusion

T-PRF/PRF with and without antibiotics exhibited antimicrobial activity on Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis over the observed 4-day period.

Chronic periodontitis and risk of cerebro-cardiovascular diseases among older Koreans

BACKGROUND AND OBJECTIVE

There is a relative lack of evidence from observational studies of older populations investigating the association between chronic periodontitis and cerebro-cardiovascular diseases. Accordingly, we investigated the risk of cerebro-cardiovascular diseases according to the severity of chronic periodontitis among older adults.

METHODS

Data on older adults with chronic periodontitis were extracted from the Korea National Health Insurance Service-Senior Cohort Database using diagnosis codes and dental procedures. Participants were divided into two exposure groups. Among 46 737 participants eligible for inclusion, 21 905 (46.9%) had newly diagnosed mild chronic periodontitis, and 24 832 (53.1%) had newly diagnosed severe chronic periodontitis. To determine the risk of cerebro-cardiovascular diseases, including ischemic stroke, haemorrhagic stroke, and myocardial infarction, multivariable-adjusted Cox proportional hazards modelling was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) in this retrospective follow-up study.

RESULTS

A total of 3453 (7.4%) outcomes were identified during a mean follow-up of 6.1 years. Kaplan-Meier analysis revealed that disease-free probability was lower in the severe group than in the mild group (log-rank P < .001). In the multivariable-adjusted model, the HR for cerebro-cardiovascular diseases in the severe group (relative to the mild group) was 1.16 (95% CI: 1.09-1.25). In individual outcome analysis, ischemic stroke and myocardial infarction were associated with chronic periodontitis severity, but haemorrhagic stroke was not.

CONCLUSION

The severity of chronic periodontitis could be associated with the risk of cerebro-cardiovascular diseases in older adults.

Association between gingivitis, tooth loss and cardiovascular risk: Insights from a 10-year nationwide cohort study of 3.7 million Koreans

BACKGROUND

While studies have suggested an association between periodontal disease and an increased risk of cardiovascular disease, the strength of this association and its specific links to various types of cardiovascular disease have not been thoroughly investigated. This study aimed to examine how gingivitis and tooth loss affect cardiovascular diseases, probing their individual impacts.

METHODS

A retrospective cohort study was conducted, encompassing 3,779,490 individuals with no history of cardiovascular disease, utilizing data from the National Health Examination and the Korean National Health Insurance database from 2006 to 2019. Cox proportional hazards models were applied to estimate the association between tooth loss, gingivitis, and cardiovascular disease.

RESULTS

Following a median follow-up of 10.38 years, 17,942 new cardiovascular disease cases were identified, comprising 10,224 cases of angina pectoris, 6,182 cases of acute myocardial infarction, and 9,536 cases of stroke. It was observed that the risk of stroke was significantly higher in the tooth loss group compared to the control group (adjusted hazard ratio [aHR]: 1.09, 95% confidence interval [CI]: 1.04-1.15). In the group with gingivitis and tooth loss, the risk of stroke and cardiovascular disease was significantly higher than in the control group (aHR: 1.12, 95% CI: 1.04-1.20; aHR: 1.08, 95% CI: 1.03-1.14). The gingivitis group exhibited a higher risk associated with stroke (aHR: 1.05, 95% CI: 1.01-1.10) among individuals aged 50 and above. However, statistically significant associations between periodontal disease and angina pectoris were not observed, nor between periodontal disease and acute myocardial infarction except among those aged above 50. Furthermore, the association between periodontal disease and cardiovascular disease was found to be stronger among individuals over the age of 50, males, those with obesity, and smokers compared to the control group.

CONCLUSIONS

Our results emphasize the association of tooth loss and gingivitis with cardiovascular disease, specifically stroke, underlining the critical need for preventive oral healthcare. Tailored interventions are necessary to reduce the heightened risk of cardiovascular disease events, especially stroke, among older, obese individuals and smokers.

Bacterial Protein Signatures Identified in Porphyromonas gingivalis Containing-Autophagic Vacuoles Reveal Co-Evolution Between Oral Red/Orange Complex Bacteria and Gut Bacteria

Modern oral bacterial species present as a concoction of commensal and opportunistic pathogens originating from their evolution in humans. Due to the intricate colonization mechanisms shared amongst oral and gut bacteria, these bacteria have likely evolved together to establish and adapt in the human oro-digestive tract, resulting in the transfer of genetic information. Our liquid chromatography-with-tandem-mass-spectrometry (LC-MS-MS) analyses have revealed protein signatures, Elongation Factor Tu, RagB/SusD nutrient uptake outer membrane protein and DnaK, specifically from Porphyromonas gingivalis -containing autophagic vacuoles isolated from the infected human primary gingival epithelial cells. Interestingly, our Mass-Spectrometry analysis reported similar proteins from closely related oral bacteria, Tannerella forsythia and Prevotella intermedia . In our phylogenetic study of these key protein signatures, we have established that pathogenic oral bacteria share extensive relatedness to each other and gut resident bacteria. We show that in the virulence factors identified from gut bacteria, Elongation Factor Tu and DnaK, there are several structural similarities and conservations with proteins from oral pathogenic bacteria. There are also major similarities in the RagB/SusD proteins of oral bacteria to prominent gut bacteria. These findings not only highlight the shared virulence mechanisms amongst oral bacterial pathogens/pathobionts but also gut bacteria and elucidate their co-evolutions in the human host.

Quality Assessment of Internet Information Regarding Periodontitis in Persons Living with HIV

The Internet is the most used source of HIV information second to information received from healthcare professionals. The aim of this study was to assess the quality of Internet information about periodontitis in people living with HIV (PLWH). An Internet search was performed on 18 April 2024 using the search terms "Periodontitis", "Periodontal disease", and "Gum disease" in combination with "HIV" in the most popular search engines (Google™, Bing™, and YAHOO!®). The first 20 results from each search term engine were pooled for analysis. Quality was assessed by JAMA benchmarks. Readability was assessed using the Flesch reading ease score (FRES). Origin of the site, type of author, and information details were also recorded. The quality of Internet information about periodontitis in PLWH varied. The mean JAMA score was 2.81 (SD = 1.0). The websites were generally fairly difficult to read (mean FRES = 57.1, SD = 15.0). Most websites provided some advice about self-treatment of oral problems, accompanied by a strong recommendation to seek professional dental care. In conclusion, advanced reading skills on periodontitis in PLWH were required and quality features were mostly not provided. Therefore, healthcare professionals should be actively involved in developing high-quality information resources and direct patients to evidence-based materials on the Internet.

Antibacterial activities of phytochemicals against Porphyromonas gingivalis with and without experimental fluoride varnish for periodontal disease prevention

We aimed to evaluate the antibacterial activity of phytochemicals with or without an experimental fluoride varnish against Porphyromonas gingivalis. Five phytochemicals, chrysophanol (CHR), emodin (EMO), anthrarufin (ANT), bavachalcone (BCC), and isobavachromene (IBC), were tested using agar diffusion, minimal inhibition concentration (MIC), and minimum bacterial concentration (MBC) assays. We also assessed the cell viability and cytotoxicity of phytochemicals. All phytochemicals showed clear inhibition zones in the agar diffusion test. The inhibition zones of all phytochemical-containing fluoride varnishes were similar to or larger than that of the positive control, excluding that of 1 mM EMO. With or without the fluoride varnish, BCC exhibited the lowest MIC and MBC levels. Cell viability was high in the presence of all phytochemicals except 200 μM EMO. In conclusion, BCC was most effective as a phytochemical alone, while all phytochemical-containing fluoride varnishes inhibited P. gingivalis growth without cytotoxicity.

Therapeutic Effects of Hinokitiol through Regulating the SIRT1/NOX4 against Ligature-Induced Experimental Periodontitis

Hinokitiol (HKT) is one of the essential oil components found in the heartwood of Cupressaceae plants, and has been reported to have various bioactive effects, including anti-inflammatory effects. However, the improving effect of HKT on periodontitis, which is characterized by periodontal tissue inflammation and alveolar bone loss, has not been clearly revealed. Therefore, we investigated the periodontitis-alleviating effect of HKT and the related molecular mechanisms in human periodontal ligament cells. According to the study results, HKT downregulated SIRT1 and NOX4, which were increased by Porphyromonas gingivalis Lipopolysaccharide (PG-LPS) stimulation and were found to regulate pro-inflammatory mediators and oxidative stress through SIRT1/NOX4 signals. Additionally, by increasing the expression of osteogenic makers such as alkaline phosphatase, osteogenic induction of human periodontal ligament (HPDL) cells, which had been reduced by PG-LPS, was restored. Furthermore, we confirmed that NOX4 expression was regulated through regulation of SIRT1 expression with HKT. The in vitro effect of HKT on improving periodontitis was proven using the periodontal inflammation model, which induces periodontal inflammation using ligature, a representative in vivo model. According to in vivo results, HKT alleviated periodontal inflammation and restored damaged alveolar bone in a concentration-dependent manner in the periodontal inflammation model. Through this experiment, the positive effects of HKT on relieving periodontal tissue inflammation and recovering damaged alveolar bone, which are important treatment strategies for periodontitis, were confirmed. Therefore, these results suggest that HKT has potential in the treatment of periodontitis.

The Role of Sulfhydryl (Thiols) Groups in Oral and Periodontal Diseases

AIM

The sulfhydryl (thiols) group of glutathione plays an important role in the neutralization of foreign organic compounds and the reduction in peroxides. The purpose of the study is to evaluate the concentration of sulfhydryl groups in the gingival tissue of healthy individuals and those with gingivitis or periodontitis, and to examine the differences between these groups.

MATERIAL AND METHODS

To assess the concentration of sulfhydryl groups (thiols) in the gingival tissue of healthy individuals and those with gingivitis or periodontitis, we used spectrophotometric analysis using dithionitrobenzoate (DTNB) as a reagent to measure the accessible sulfhydryl groups present in gingival tissue proteins. The sample was divided into three distinct groups: individuals with periodontal health, gingivitis, and periodontitis, and different indices were used to assess the periodontal status of the participants. Next, a statistical analysis was conducted to compare the concentrations of sulfhydryl groups among the different groups of patients.

CONCLUSIONS

The results of this study showed significantly decreased levels of sulfhydryl (thiols) groups in gingival tissue from patients with gingivitis and periodontitis, compared with healthy people (control group). These results confirm the role of sulfhydryl (thiols) groups in defense against free radicals. They share a significant role in detoxification, signal transduction, apoptosis, and various other functions at the molecular level.

Association of F. alocis and D. pneumosintes with Periodontitis Disease Severity and Red Complex Bacteria

Oral biofilms are considered the principal etiological agent in the development of periodontitis. Novel species that may contribute to periodontitis and dysbiosis have been identified recently. The study aims to evaluate the presence of F. alocis and D. pneumosintes in healthy and diseased patients and their association with clinical parameters and with red complex bacteria. The study included 60 subjects, with 30 patients each in the healthy and periodontitis groups. The clinical parameters were noted, and samples were subjected to DNA extraction followed by a polymerase chain reaction. Statistical analysis was performed using the Graph Pad Prism software. Results: F. alocis and D. pneumosintes were detected at a significantly higher percentage in the periodontitis group compared to the healthy group (p < 0.05). D. pneumosintes was significantly associated with T. forsythia in the periodontitis group (p < 0.05). Both of these organisms were present in sites with higher clinical attachment loss (p < 0.05). This study demonstrated that both F. alocis and D. pneumosintes were detected at a significantly higher percentage in periodontitis subjects and were detected more frequently in sites with a greater clinical attachment loss. It was also evident that both F. alocis and D. pneumosintes can be present independently of other putative periodontal pathogens.

Influence of the severity of periodontal disease on the outcome of non-surgical endodontic therapy: A prospective cohort study

OBJECTIVE

To investigate the influence of severity of periodontal disease on periapical healing after non-surgical endodontic therapy (NSET).

MATERIAL AND METHODS

In this prospective study, subjects (n = 45) requiring NSET in a mandibular molar tooth with the diagnosis of pulp necrosis and asymptomatic apical periodontitis exhibiting radiographic periapical index (PAI) score ≥ 3 and concomitant endodontic periodontal lesion (CEPL) without communication were enrolled. After dividing as per the classification of Periodontal and Peri-Implant Diseases and Conditions, subjects were equally allocated into three groups. Group I- only endodontic lesion {control: healthy periodontium (n = 15)}, Group II- CEPL having stage I and II periodontitis (n = 15) and Group III- CEPL having stage III periodontitis (n = 15). Standardized two-visit NSET was performed with 2% chlorhexidine gel as an intracanal medicament. Periodontal therapy was instituted wherever required. Subjects were recalled at 6-and 12-months for clinical and radiographic assessment. Chi-square test was performed to evaluate the difference between the groups.

RESULTS

At 12-month follow-up, all teeth in the three study groups were asymptomatic. On radiographic evaluation of the periapical region, healing was observed in 80%, 47% and 50% of teeth in Groups I, Group II and Group III, respectively. However, the difference was not statistically significant between the groups (p = 0.150).

CONCLUSION

The severity of periodontal disease had no influence on periapical healing after NSET in teeth with concomitant endodontic periodontal lesions without communication.

CLINICAL RELEVANCE

Periodontal disease has significant impact on apical periodontitis however severity of the periodontitis does not negatively impact the apical periodontitis.

Acquired Pellicle and Biofilm Engineering by Rinsing with Hemoglobin Solution

INTRODUCTION

The identification of acid-resistant proteins, including hemoglobin (Hb), within the acquired enamel pellicle (AEP) led to the proposition of the "acquired pellicle engineering" concept, which involves the modification of the AEP by incorporating specific proteins, presenting a novel strategy to prevent dental demineralization.

OBJECTIVE

Combining in vivo and in vitro proof-of-concept protocols, we sought to reveal the impact of AEP engineering with Hb protein on the biofilm microbiome and enamel demineralization.

METHODS

In the in vivo studies, 10 volunteers, in 2 independent experiments, rinsed (10 mL,1 min) with deionized water-negative control or 1.0 mg/mL Hb. The AEP and biofilm formed along 2 or 3 h, respectively, were collected. AEP was analyzed by quantitative shotgun-label-free proteomics and biofilm by 16S-rRNA next-generation sequencing (NGS). In in vitro study, a microcosm biofilm protocol was employed. Seventy-two bovine enamel specimens were treated with (1) phosphate-buffered solution (PBS), (2) 0.12% chlorhexidine, (3) 500 ppm NaF, (4) 1.0 mg/mL Hb, (5) 2.0 mg/mL Hb, and (6) 4.0 mg/mL Hb. The biofilm was cultivated for 5 days. Resazurin, colony forming units (CFU), and transversal microradiography were performed.

RESULTS

Proteomics and NGS analysis revealed that Hb increased proteins with antioxidant, antimicrobial, acid-resistance, hydroxyapatite-affinity, calcium-binding properties and showed a reduction in oral pathogenic bacteria. In vitro experiments demonstrated that the lowest Hb concentration was the most effective in reducing bacterial activity, CFU, and enamel demineralization compared to PBS.

CONCLUSION

These findings suggest that Hb could be incorporated into anticaries dental products to modify the oral microbiome and control caries, highlighting its potential for AEP and biofilm microbiome engineering.

Effects of mouthwash on periodontal pathogens and glycemic control in patients with type 2 diabetes mellitus

Periodontitis is known to be associated with type 2 diabetes mellitus (T2DM), and gargling with mouthwash is known to reduce the incidence of periodontitis by inhibiting periodontal pathogens. However, the effects of mouthwash on oral and systemic conditions in patients with T2DM remain unknown. In this study, we investigated the effects of gargling with mouthwash on the number of red complex species, including Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, and HbA1c levels in patients with T2DM. Patients were instructed to gargle with water for 6 months, followed by gargling with mouthwash containing chlorhexidine gluconate for the subsequent 6 months. At each clinic visit, saliva was collected and bacterial DNA was extracted to detect red complex species using the polymerase chain reaction technique. The HbA1c level was determined using a blood sample. The number of red complex species significantly decreased in younger or male patients who gargled with mouthwash. Furthermore, HbA1c levels significantly decreased in younger patients or patients with higher HbA1c levels who gargled with mouthwash. These results suggest that gargling with mouthwash reduces the number of red complex species and improves the hyperglycemic status in patients with T2DM, especially younger patients.

Personalized antibiotic selection in periodontal treatment improves clinical and microbiological outputs

Introduction

Periodontitis is a biofilm-mediated disease that is usually treated by non-surgical biofilm elimination with or without antibiotics. Antibiotic treatment in periodontal patients is typically selected empirically or using qPCR or DNA hybridization methods. These approaches are directed towards establishing the levels of different periodontal pathogens in periodontal pockets to infer the antibiotic treatment. However, current methods are costly and do not consider the antibiotic susceptibility of the whole subgingival biofilm.

Methods

In the current manuscript, we have developed a method to culture subgingival samples ex vivo in a fast, label-free impedance-based system where biofilm growth is monitored in real-time under exposure to different antibiotics, producing results in 4 hours. To test its efficacy, we performed a double-blind, randomized clinical trial where patients were treated with an antibiotic either selected by the hybridization method (n=32) or by the one with the best effect in the ex vivo growth system (n=32).

Results

Antibiotic selection was different in over 80% of the cases. Clinical parameters such as periodontal pocket depth, attachment level, and bleeding upon probing improved in both groups. However, dental plaque was significantly reduced only in the group where antibiotics were selected according to the ex vivo growth. In addition, 16S rRNA sequencing showed a larger reduction in periodontal pathogens and a larger increase in health-associated bacteria in the ex vivo growth group.

Discussion

The results of clinical and microbiological parameters, together with the reduced cost and low analysis time, support the use of the impedance system for improved individualized antibiotic selection.

Association between rheumatoid arthritis and pulpal-periapical pathology: a systematic review

OBJECTIVES

Rheumatoid arthritis (RA) is a debilitating disease where numerous pro-inflammatory cytokines have a proven role in its pathology. These cytokines are also involved in the pathogenesis of apical periodontitis (AP) where they have a pro-inflammatory role and induce bone resorption. Patients with RA may therefore be more prone to develop pulpal-periapical pathology (PPP). This study systematically reviewed the existing literature evaluating the association between RA and PPP.

MATERIALS AND METHODS

Studies including human participants with both RA and PPP were included. The search was performed in PubMed, Web of Science, and The Cochrane Library databases using keywords and Medical Subject Headings (MeSH) search terms. The risk of bias was assessed using Newcastle-Ottawa Quality Assessment Scale. The following parameters were extracted and analyzed by the reviewers; author, journal, year, design of the study, diagnostic criteria for periapical pathology, the association between rheumatoid arthritis and periapical pathology, and the evidence level.

RESULTS

The search identified 142 records. Inclusion criteria were as follows; studies in the English language, including human participants only, including patients with RA and PPP, cohort studies, cross-sectional studies, clinical trials, and case-control studies. According to the inclusion criteria, 5 studies were included in this systematic review. Three of the five studies reported significant association between RA and PPP.

CONCLUSIONS

Existing evidence suggests there may be an association between RA and PPP.

CLINICAL RELEVANCE

Clinicians should be aware that RA patients can be more prone to develop PPP which may result in a reduced quality of life.

Application of Different Wavelengths of LED Lights in Antimicrobial Photodynamic Therapy for the Treatment of Periodontal Disease

Therapeutic light has been increasingly used in clinical dentistry for surgical ablation, disinfection, bio-stimulation, reduction in inflammation, and promotion of wound healing. Photodynamic therapy (PDT), a type of phototherapy, has been used to selectively destroy tumor cells. Antimicrobial PDT (a-PDT) is used to inactivate causative bacteria in infectious oral diseases, such as periodontitis. Several studies have reported that this minimally invasive technique has favorable therapeutic outcomes with a low probability of adverse effects. PDT is based on the photochemical reaction between light, a photosensitizer, and oxygen, which affects its efficacy. Low-power lasers have been predominantly used in phototherapy for periodontal treatments, while light-emitting diodes (LEDs) have received considerable attention as a novel light source in recent years. LEDs can emit broad wavelengths of light, from infrared to ultraviolet, and the lower directivity of LED light appears to be suitable for plaque control over large and complex surfaces. In addition, LED devices are small, lightweight, and less expensive than lasers. Although limited evidence exists on LED-based a-PDT for periodontitis, a-PDT using red or blue LED light could be effective in attenuating bacteria associated with periodontal diseases. LEDs have the potential to provide a new direction for light therapy in periodontics.

Ozone Therapy as an Adjuvant in the Treatment of Periodontitis

The current study aimed to assess the efficacy of ozone therapy in the treatment of stage II and stage III periodontitis. This prospective split-mouth study selected patients who were diagnosed with either stage II or stage III periodontitis. All patients were treated with scaling and root-planing (SRP) on the control side and SRP with ozone therapy on the test side. Probing depth (PD), clinical attachment loss (CAL), O'Leary plaque index (PI), and bleeding on probing (BOP) scores were recorded at baseline and six weeks after the SRP treatment. A total of 46 patients were selected for this study, including 31 males and 15 females. All periodontal variables (PD, CAL, PI, and BOP) showed significant changes (p < 0.0001) from baseline to six weeks. Moreover, significant changes (PD = 0.0001, CAL = 0.0001, PI = 0.042 and BOP = 0.0001) were also observed between the control and test sides. Gender showed no significance on periodontal variables (p > 0.05) except PD on the test side (p = 0.030). In addition, periodontal stages and grades showed no significant changes (p > 0.05) in any periodontal variables on both sides. Ozone therapy significantly improves the periodontal condition compared to SRP treatment alone. However, the stages and grades of periodontitis do not influence the outcome of ozone therapy.

Community dynamics of subgingival microbiome in periodontitis and targets for microbiome modulation therapy

The microbial aetiology for periodontitis has been widely studied and deciphered for more than a century. The evolving and changing concepts about periodontal microbiology can be attributed to continuously developing laboratory techniques. The current sequencing platforms have not only expanded the catalog of periodontal pathogens but have also facilitated the understanding of functional interactions of the ecological framework. However, the translation of this new knowledge to advance periodontal therapeutics is minimal. We contend that novel clinical interventions directed beyond conventional therapies need to be emphasized. A clear understanding of the structural and functional dynamics of subgingival microbiota is a pre-requisite for developing any microbiome-based interventions for applications in periodontal health care. In this review, we discuss the 16 s-rRNA gene sequencing-based knowledge of the subgingival microbial community structure, its interactions and functions, and our perspective on the potential to engineer it for periodontal therapeutics. Harnessing this next-generation sequencing-based knowledge, microbiome modulation therapies are poised to change microbiome therapeutics' face.

Implications of Gene Therapy in Dentistry and Periodontics: A Narrative Review

The relentless march of technological progress entails constant evolution and adaptation. A concerted effort is underway in medical research to unravel various diseases' cellular and molecular underpinnings. The traditional approaches to disease treatment often fall short of delivering entirely satisfactory outcomes, which has prompted a shifting spotlight on gene therapy as a versatile solution for many inherited and acquired disorders. Genes, intricate sequences of genetic code, are the complicated blueprints dictating the production of essential proteins within the human body. Remarkably, each individual's genetic makeup is uniquely distinct, with variations in these genetic sequences serving as the bedrock of our diversity. Gene therapy represents an innovative medical strategy that harnesses the power of genes themselves to function as therapeutic agents. It serves as a conduit through which defective genes are either substituted or mended with the introduction of remedial genetic material. This groundbreaking method can tackle various illnesses, from conditions originating from single-gene abnormalities to intricate disorders influenced by multiple genes. In dentistry and periodontics, gene therapy finds a promising array of applications. It contributes significantly to managing salivary gland disorders, autoimmune diseases, and the regeneration of damaged bone tissue, as well as addressing cancerous and precancerous conditions. Moreover, the possibilities extend into DNA vaccination and broader areas of oral health. The advent of gene therapy in dentistry represents a new era of significant progress, offering substantial advancements in the management of periodontal disease and the reconstruction of the dental alveolar apparatus. The aim of this narrative review is to provide a comprehensive overview of the landscape of gene therapy investigations in these disciplines, shedding light on its potential implications for oral health and treatment. With its potential to rectify the genetic underpinnings of various conditions, gene therapy offers a novel frontier in healthcare that continually shapes the landscape of medicine and holds the promise of more effective and personalised treatments.

Guided Bone Regeneration Using Barrier Membrane in Dental Applications

Guided bone regeneration (GBR) is a widely used technique in preclinical and clinical studies due to its predictability. Its main purpose is to prevent the migration of soft tissue into the osseous wound space, while allowing osseous cells to migrate to the site. GBR is classified into two main categories: resorbable and non-resorbable membranes. Resorbable membranes do not require a second surgery but tend to have a short resorption period. Conversely, non-resorbable membranes maintain their mechanical strength and prevent collapse. However, they require removal and are susceptible to membrane exposure. GBR is often used with bone substitute graft materials to fill the defect space and protect the bone graft. The membrane can also undergo various modifications, such as surface modification and biological factor loading, to improve barrier functions and bone regeneration. In addition, bone regeneration is largely related to osteoimmunology, a new field that focuses on the interactions between bone and the immune system. Understanding these interactions can help in developing new treatments for bone diseases and injuries. Overall, GBR has the potential to be a powerful tool in promoting bone regeneration. Further research in this area could lead to advancements in the field of bone healing. This review will highlight resorbable and non-resorbable membranes with cellular responses during bone regeneration, provide insights into immunological response during bone remodeling, and discuss antibacterial features.

Efficacy of hypochlorous acid as an alternative oral antimicrobial agent on human gingival fibroblasts, Aggregatibacter actinomycetemcomitans, and Candida albicans biofilms in vitro

This study compared the cytotoxicity and antimicrobial activity of hypochlorous acid (HOCl) at 50 ppm and 200 ppm and 0.2% chlorhexidine (CHX) at various time intervals, in vitro. Cell viability and cytotoxicity of human gingival fibroblasts (HGF) were evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test and the lactate dehydrogenase assay. Antimicrobial effects on Aggregatibacter actinomycetemcomitans and Candida albicans were determined using the time-kill method. All solutions exhibited a significant impact on HGFs in a dose- and time-dependent manner. 50 ppm HOCl demonstrated the highest cell viability, followed by 200 ppm HOCl. Both HOCl solutions were less cytotoxic to HGFs than 0.2% CHX. 50 ppm and 200 ppm HOCl demonstrated stronger efficiencies than CHX against A. actinomycetemcomitans and C. albicans. The data suggest that HOCl solutions have potential as an alternative antiseptic to CHX due to their lower cytotoxicity and superior antimicrobial activity, but optimal dosage of HOCl requires further investigations.

Recent progress in carbon dots for anti-pathogen applications in oral cavity

Background

Oral microbial infections are one of the most common diseases. Their progress not only results in the irreversible destruction of teeth and other oral tissues but also closely links to oral cancers and systemic diseases. However, traditional treatment against oral infections by antibiotics is not effective enough due to microbial resistance and drug blocking by oral biofilms, along with the passive dilution of the drug on the infection site in the oral environment.

Aim of review

Besides the traditional antibiotic treatment, carbon dots (CDs) recently became an emerging antimicrobial and microbial imaging agent because of their excellent (bio)physicochemical performance. Their application in treating oral infections has received widespread attention, as witnessed by increasing publication in this field. However, to date, there is no comprehensive review available yet to analyze their effectiveness and mechanism. Herein, as a step toward addressing the present gap, this review aims to discuss the recent advances in CDs against diverse oral pathogens and thus propose novel strategies in the treatment of oral microbial infections.

Key scientific concepts of review

In this manuscript, the recent progress of CDs against oral pathogens is summarized for the first time. We highlighted the antimicrobial abilities of CDs in terms of oral planktonic bacteria, intracellular bacteria, oral pathogenic biofilms, and fungi. Next, we introduced their microbial imaging and detection capabilities and proposed the prospects of CDs in early diagnosis of oral infection and pathogen microbiological examination. Lastly, we discussed the perspectives on clinical transformation and the current limitations of CDs in the treatment of oral microbial infections.

Parkinson's disease alters the composition of subgingival microbiome

Aim

The current study aimed to test the hypothesis that Parkinson's disease exacerbates periodontitis by altering its microbiome.

Materials and Methods

Clinical periodontal parameters were recorded. Subgingival samples from healthy controls, periodontitis patients (PD), and Parkinson's patients with periodontitis (PA+PD) were analyzed using the checkerboard DNA-DNA hybridization technique for targeting 40 bacterial species typically associated with periodontal disease and health. Next-generation sequencing (NGS) of the 16S ribosomal RNA gene (V1-V3 regions) was performed to analyze the microbiome comprehensively.

Results

Parkinson's patients had mild-to-moderate motor dysfunctions. Bleeding on probing was significantly increased in the PA+PD group compared to PD (p < 0.05). With checkerboard analysis, PA was associated with increased Treponema socranskii (p = 0.0062), Peptostreptococcaceae_[G-6] [Eubacterium]_nodatum (p = 0.0439), Parvimona micra (p < 0.0001), Prevotella melaninogenica (p = 0.0002), Lachnoanaerobaculum saburreum (p < 0.0001), and Streptococcus anginosus (p = 0.0020). Streptococcus intermedia (p = 0.0042), P.nodatum (p = 0.0022), P. micra (p = 0.0002), Treponema denticola (p = 0.0045), L.saburreum (p = 0.0267), P.melaninogenica (p = 0.0017), Campylobacter rectus (p = 0.0020), and T.socranskii (p = 0.0002) were higher; Aggregatibacter actinomycetemcomitans (p = 0.0072) was lower in deep pockets in the PA+PD compared to PD. Schaalia odontolytica (p = 0.0351) and A.actinomycetemcomitans (p = 0.002) were lower; C.rectus (p = 0.0002), P. micra (p = 0065), Streptococcus constellatus (p = 0.0151), T.denticola (p = 0.0141), P.melaninogenica (p = 0.0057), and T.socranskii (p = 0.0316) were higher in shallow pockets in the PA+PD. Diversity decreased in PD (p = 0.001) and PA+PD (p = 0.026) compared to control, with minimal differences in alpha and beta diversities among PD and PA+PD based on NGS results.

Conclusion

These data demonstrated that Parkinson's disease modifies PD-associated subgingival microbiome.

Link between Oral Health, Periodontal Disease, Smoking, and Systemic Diseases in Romanian Patients

(1) Background: The link between oral and systemic health is becoming increasingly obvious. Oral diseases, particularly periodontitis, have been linked to various diseases including diabetes and cardiovascular disease, among others. This survey aimed to assess the oral health condition of individuals, considering both their overall health and periodontal status, by performing oral examinations and collecting data using questionnaires. (2) Methods: After obtaining approval from the University's Ethics Committee, the study was carried out from 2021 to 2022 at the Department of Oral Health, located in the Emergency Municipal Hospital in Timisoara, Timis County, Romania. Bivariate correlations were performed using nonparametric Spearman's Rho using SPPS software version 23. To assess the importance of smoking frequency related to the severity of periodontitis diagnosis, the ANOVA Simple test (one-way) and Hochberg GT2 post hoc analysis were utilized. The chi-squared test was employed for nominal variables. A significance level of 0.05 (alpha = 0.05) was adopted for all statistical tests. (3) Results: There is a significant positive association between the frequency of systemic disease and the severity of the periodontitis diagnosis taken as a total, Rho (242) = 0.151, p < 0.05, and taken as a stage, Rho (242) = 0.199, p < 0.01, thus as the severity of the diagnosis increases, the patient presents comorbidities. Hochberg GT2 post hoc analysis indicates that the non-smoking group has statistically significantly lower diagnostic severity (Mdif = -0.81, p = 0.01), with a strong effect size (Cohen's d = 0.73). (4) Conclusions: The findings are increasingly indicating a potential association between oral diseases and a range of systemic diseases. The impact of periodontal disease on the quality of life is significant, especially in individuals with associated systemic conditions and present risk factors.

Temporal changes of periodontal tissue pathology in a periodontitis animal model

PURPOSE

This study aimed to characterize the early stages of periodontal disease and determine the optimal period for its evaluation in a mouse model. The association between the duration of ligation and its effect on the dentogingival area in mice was evaluated using micro-computed tomography (CT) and histological analysis.

METHODS

Ninety mice were allocated to an untreated control group or a ligation group in which periodontitis was induced by a 6-0 silk ligation around the left second maxillary molar. Mice were sacrificed at 1, 2, 3, 4, 5, 8, 11, and 14 days after ligature placement. Alveolar bone destruction was evaluated using micro-CT. Histological analysis was performed to assess the immune-inflammatory processes in the periodontal tissue.

RESULTS

No significant difference in alveolar bone loss was found compared to the control group until day 3 after ligature placement, and a gradual increase in alveolar bone loss was observed from 4 to 8 days following ligature placement. No significant between-group differences were observed after 8 days. The histological analysis demonstrated that the inflammatory response was evident from day 4.

CONCLUSIONS

Our findings in a mouse model provide experimental evidence that ligature-induced periodontitis models offer a consistent progression of disease with marginal attachment down-growth, inflammatory infiltration, and alveolar bone loss.

Methods for Evaluating the Effectiveness of Home Oral Hygiene Measures-A Narrative Review of Dental Biofilm Indices

Dental plaque is a biofilm structured in an extracellular matrix of polymers of host and microbial origin; the microorganisms can coexist in harmony with the host, thus guarantying oral health. Environmental modifications can lead to dysbiosis and onset of oral diseases; in fact, plaque is the etiological agent both of periodontal disease and dental decay. The use of an effective oral hygiene index should be considered as a relevant goal for the clinicians and the researchers, and consequently, numerous plaque indices have been proposed during the years. The present literature review aims primarily to obtain a complete summary of these scores to assess plaque deposits. It is useful because the clinician/researcher will select the right scoring method for the specific situation only if he knows the available options and if he is aware of both their strengths and weaknesses. This review applies a basic classification of plaque indices that distinguishes the ones that use non-quantitative methods from the ones that use quantitative methods. Non-quantitative methods are more subjective because they are based on the ability of the clinician to point out the presence or the entity of deposits, while quantitative methods introduce objectifiable means to measure plaque deposits.

Adjunctive use of locally delivered host-modulators in intra-bony defects as part of step 2 periodontal therapy: systematic review, meta-analysis and trial sequential analysis

BACKGROUND

This systematic review and meta-analysis aimed at investigate the role of locally delivered host-modulators in combination with step 2 of periodontal therapy in reducing probing pocket depth, improving clinical attachment level and reducing bone defect depth in intra-bony defects.

HIGHLIGHT

RCT with at least 6 months follow-up were included in this study. Risk of bias assessment was performed with Cochrane collaboration tool and Grade GRADEpro. In addition, meta-analysis and trial sequential analysis were used to aggregate the available evidence. 22 studies met the inclusion criteria and were included in this systematic review. At 6 months locally delivered host-modulators significantly improved PD and CAL and bone defect depth.

CONCLUSION

Considering the emerging role of host-inflammatory response in the treatment of periodontitis, several studies are exploring the role of locally delivered host modulators as an adjunct to step 2 of periodontal therapy.

Interactions between systemic diseases and oral microbiota shifts in the aging community: A narrative review

As a gateway to general health and a diverse microbial habitat, the oral cavity is colonized by numerous microorganisms such as bacteria, fungi, viruses, and archaea. Oral microbiota plays an essential role in preserving oral health. Besides, the oral cavity also significantly contributes to systemic health. Physiological aging influences all body systems, including the oral microbial inhabitants. The cited effect can cause diseases by forming dysbiotic communities. Since it has been demonstrated that microbial dysbiosis could disturb the symbiosis state between the host and the resident microorganism, shifting the condition toward a more pathogenic one, this study investigated how the oral microbial shifts in aging could associate with the development or progression of systemic diseases in older adults. The current study focused on the interactions between variations in the oral microbiome and prevalent diseases in older adults, including diabetes mellitus, Sjögren's syndrome, rheumatoid arthritis, pulmonary diseases, cardiovascular diseases, oral candidiasis, Parkinson's disease, Alzheimer's disease, and glaucoma. Underlying diseases can dynamically modify the oral ecology and the composition of its resident oral microbiome. Clinical, experimental, and epidemiological research suggests the associations of systemic disorders with bacteremia and inflammation after oral microbial changes in older adults.

Green Alternatives as Antimicrobial Agents in Mitigating Periodontal Diseases: A Narrative Review

Periodontal diseases and dental caries are the most common infectious oral diseases impacting oral health globally. Oral cavity health is crucial for enhancing life quality since it serves as the entranceway to general health. The oral microbiome and oral infectious diseases are strongly correlated. Gram-negative anaerobic bacteria have been associated with periodontal diseases. Due to the shortcomings of several antimicrobial medications frequently applied in dentistry, the lack of resources in developing countries, the prevalence of oral inflammatory conditions, and the rise in bacterial antibiotic resistance, there is a need for reliable, efficient, and affordable alternative solutions for the prevention and treatment of periodontal diseases. Several accessible chemical agents can alter the oral microbiota, although these substances also have unfavorable symptoms such as vomiting, diarrhea, and tooth discoloration. Natural phytochemicals generated from plants that have historically been used as medicines are categorized as prospective alternatives due to the ongoing quest for substitute products. This review concentrated on phytochemicals or herbal extracts that impact periodontal diseases by decreasing the formation of dental biofilms and plaques, preventing the proliferation of oral pathogens, and inhibiting bacterial adhesion to surfaces. Investigations examining the effectiveness and safety of plant-based medicines have also been presented, including those conducted over the past decade.

Better living through chemistry? A randomized, double-blind controlled study evaluating the efficacy of plaque control and gingival health impacts of a novel stannous fluoride-containing gel

BACKGROUND

Gingivitis is a nonspecific inflammatory lesion in response to the accumulation of oral biofilm and is a necessary precursor to periodontitis. Enhanced oral hygiene practices are necessary to reverse gingivitis and a dentifrice that could provide significant clinical reductions in plaque accumulation and gingival inflammation would be desirable to treat gingivitis and potentially prevent progression to periodontitis. This clinical study aimed to investigate the effect of a novel stannous fluoride-containing dentifrice with 2.6% ethylenediamine tetra-acetic acid (EDTA) as an antitartar agent to reduce Plaque Index (PI) and Gingival Index over a 3-month study period.

METHODS

This double-blind, randomized controlled clinical study evaluated plaque, gingival inflammation, and sulcular bleeding in patients using either a novel dental gel containing 0.454% stannous fluoride and 2.6% EDTA or a dentifrice with 0.24% sodium fluoride. Sixty subjects participated over a 3-month period. Co-primary endpoints were improvements in PI and Modified Gingival Index (mGI) from baseline values. No professional cleaning was performed during the study period.

RESULTS

All subjects in the study demonstrated statistically significant improvements in all measures of oral hygiene over the 3-month study period. Subjects using the novel dental gel showed statistically significantly greater reductions in PI (ΔPI) [(-1.43 ± 0.34; -0.49 ± 0.13) (p < 0.00001)], mGI (ΔmGI) [(-1.11 ± 0.22; -0.16 ± 0.12) (p < 0.00001)], and modified sulcular bleeding index (ΔmSBI) [(-1.15 ± 0.18; -0.20 ± 0.07) (p < 0.00001)].

CONCLUSIONS

The novel dental gel demonstrated significant improvements in clinical parameters associated with gingivitis compared to a commercially available sodium fluoride dentifrice.

Vasohibin-1 promotes osteoclast differentiation in periodontal disease by stimulating the expression of RANKL in gingival fibroblasts

Vasohibin-1 (VASH1) is a key inhibitor of vascular endothelial growth factor-induced angiogenesis. Although the involvement of VASH1 in various pathological processes has been extensively studied, its role in periodontal disease (PD) remains unclear. We aimed to investigate the role of VASH1 in PD by focusing on osteoclastogenesis regulation. We investigated VASH1 expression in PD by analyzing data from the online Gene Expression Omnibus (GEO) database and using a mouse ligature-induced periodontitis model. The effects of VASH1 on osteoclast differentiation and osteoclastogenesis-supporting cells were assessed in mouse bone marrow-derived macrophages (BMMs) and human gingival fibroblasts (GFs). To identify the stimulant of VASH1, we used culture broth from Porphyromonas gingivalis (Pg), a periopathogen. The GEO database and mouse periodontitis model revealed that VASH1 expression was upregulated in periodontitis-affected gingival tissues, which was further supported by immunohistochemistry and qRT-PCR analyses. VASH1 expression was significantly stimulated in GFs after treatment with the Pg broth. Direct treatment with recombinant VASH1 protein did not stimulate osteoclast differentiation in BMMs but did contribute to osteoclast differentiation by inducing RANKL expression in GFs through a paracrine mechanism. Small interfering RNA-mediated silencing of VASH1 in GFs abrogated RANKL-mediated osteoclast differentiation in BMMs. Additionally, VASH1-activated RANKL expression in GFs was significantly suppressed by MK-2206, a selective inhibitor of AKT. These results suggest that Pg-induced VASH1 may be associated with RANKL expression in GFs in a paracrine manner, contributing to osteoclastogenesis via an AKT-dependent mechanism during PD progression.

Immune markers and microbial factors are related with periodontitis severity in people with HIV

OBJECTIVE

The objective of the study is to assess systemic immune markers and microbial factors related to periodontitis severity in people living with HIV.

METHODS

Eighty people living with HIV (PLWH), who exhibited in the last two viral load measurements < 40 copies/mL, underwent full-mouth periodontal examinations and sub-gingival plaque sampling. Periodontitis was classified according to the CDC-AAP case definition. Inflammation, immune-activation, and immunosenescence markers were assessed, microbiological analyses were performed, and oral care routines and HIV characteristics were noted.

RESULTS

From our group of PLWH, 42.5% and 57.5% suffered from moderate and severe periodontitis, respectively. Oral care habits did not differ between PLWH with moderate and severe periodontitis. Bacterial subgingival plaque loads were higher, and Porphyromonas gingivalis was more prevalent in PLWH with severe periodontitis than with moderate periodontitis (53% vs 7%, respectively). Mean C-reactive protein levels [CRP, 1.6 mg/L versus 0.8 mg/L, p = 0.020] and percentages of senescent CD28-CD57 + CD8 + T-cells in peripheral blood [16.5 versus 8.9, p = 0.035] were higher with severe periodontitis. Infection duration, CD4 count, CD4/CD8 ratio and type of antiretroviral therapy did not differ between both groups.

CONCLUSIONS

Periodontitis severity is related to increased prevalence of Porphyromonas gingivalis, elevated CRP levels, and higher frequencies of circulating CD8 + senescent cells in PLWH.

Periodontal treatment and microbiome-targeted therapy in management of periodontitis-related nonalcoholic fatty liver disease with oral and gut dysbiosis

A growing body of evidence from multiple areas proposes that periodontal disease, accompanied by oral inflammation and pathological changes in the microbiome, induces gut dysbiosis and is involved in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). A subgroup of NAFLD patients have a severely progressive form, namely nonalcoholic steatohepatitis (NASH), which is characterized by histological findings that include inflammatory cell infiltration and fibrosis. NASH has a high risk of further progression to cirrhosis and hepatocellular carcinoma. The oral microbiota may serve as an endogenous reservoir for gut microbiota, and transport of oral bacteria through the gastro-intestinal tract can set up a gut microbiome dysbiosis. Gut dysbiosis increases the production of potential hepatotoxins, including lipopolysaccharide, ethanol, and other volatile organic compounds such as acetone, phenol and cyclopentane. Moreover, gut dysbiosis increases intestinal permeability by disrupting tight junctions in the intestinal wall, leading to enhanced translocation of these hepatotoxins and enteric bacteria into the liver through the portal circulation. In particular, many animal studies support that oral administration of Porphyromonas gingivalis, a typical periodontopathic bacterium, induces disturbances in glycolipid metabolism and inflammation in the liver with gut dysbiosis. NAFLD, also known as the hepatic phenotype of metabolic syndrome, is strongly associated with metabolic complications, such as obesity and diabetes. Periodontal disease also has a bidirectional relationship with metabolic syndrome, and both diseases may induce oral and gut microbiome dysbiosis with insulin resistance and systemic chronic inflammation cooperatively. In this review, we will describe the link between periodontal disease and NAFLD with a focus on basic, epidemiological, and clinical studies, and discuss potential mechanisms linking the two diseases and possible therapeutic approaches focused on the microbiome. In conclusion, it is presumed that the pathogenesis of NAFLD involves a complex crosstalk between periodontal disease, gut microbiota, and metabolic syndrome. Thus, the conventional periodontal treatment and novel microbiome-targeted therapies that include probiotics, prebiotics and bacteriocins would hold great promise for preventing the onset and progression of NAFLD and subsequent complications in patients with periodontal disease.

Oral hygiene, mouthwash usage and cardiovascular mortality during 18.8 years of follow-up

Aim(s) We tested the following hypotheses: would better oral hygiene self-care (OHS) influence cardiovascular (CVD) mortality? Will using mouthwash in addition to OHS affect CVD mortality? How does mouthwash usage impact the oral microbes?Design and methods Among 354 dentate subjects from the Kuopio Oral Health and Heart study, the association of OHS with CVD mortality was assessed using Cox regression analyses, adjusting for age, sex, smoking, dyslipidemia, diabetes, hypertension and education. Additionally, whether using mouthwash would affect this relationship was evaluated.Results In the multivariable-adjusted models, OHS was associated with a 51% reduction in the risk of CVD mortality (hazard ratio [HR] 0.49 [0.28-0.85]; p = 0.01). Even those who had coronary artery disease at baseline showed a marginally significant benefit (0.50 [0.24-1.06]; p = 0.07). However, mouthwash usage did not change OHS effects (HR = 0.49 [0.27-0.87]; p = 0.01), indicating no additional benefits nor detriments. All tested microbes trended to decrease with mouthwash usage in the short term, but none were statistically significant.Conclusion Good OHS significantly lowered the risk of CVD mortality relative to poor OHS. Mouthwash usage did not show any long-term harm or benefit on CVD mortality beyond the benefits rendered by brushing and flossing.

Probiotic consumption can modify the resilience of periodontal tissues in rats under experimental periodontitis

BACKGROUND

This study evaluated the effects of systemic administration of Bifidobacterium animalis subsp. lactis HN019 (B. lactis HN019) on experimental periodontitis (EP) in rats.

METHODS

Thirty-two rats were allocated to groups C (control), C-HN019 (probiotic), EP (EP only), and EP-HN019 (EP+probiotic). From day 0, the animals of C-HN019 and EP-HN019 groups received B. lactis HN019 (1 × 10⁹ CFU/ml) daily. On the 14th day, the animals of EP and EP-HN019 groups received silk ligature around mandibular molars. Animals were euthanized on the 28th day. Samples of oral biofilm, gingival tissues, blood serum, and mandible were obtained for microtomographic, histomorphometric, microbiological, and immunological analyses. Data were statistically analyzed (p < 0.05).

RESULTS

Group EP-HN019 presented significantly less alveolar bone loss when compared with Group EP in histomorphometric and microtomographic analyses. In gingival tissue and serum, Group EP-HN019 presented lower proinflammatory/anti-inflammatory cytokines ratios than Group EP. Group EP-HN019 showed higher expression of beta-defensins and less TRAP-positive cells than Group EP. Group EP presented higher gene expression of Ifng and lower gene expression of Foxp3 when compared with Group EP-HN019 in gingival tissue. In oral biofilm, EP-HN019 group presented a lower percentage of species similar to Fusobacterium periodonticum and a higher percentage of species similar to Actinomyces gereneseriae, Actinomyces israelli, and Streptococcus gordonii when compared with Group EP. There was a significant increase of B. lactis HN019 after administration of probiotic therapy in oral biofilm of Group EP-HN019.

CONCLUSION

The consumption of B. lactis HN019 promotes a protective effect against alveolar bone loss by modifying local and systemic microbiological and immunoinflammatory parameters.

Applications of Gene Therapy in Dentistry: A Review Article

Gene therapy promises to possess a good prospect in bridging the gap between dental applications and medicine. The dynamic therapeutic modalities of gene therapy have been advancing rapidly. Conventional approaches are being revamped to be more comprehensive and pre-emptive, which could do away with the need for surgery and medicine altogether. The complementary base sequences known as genes convey the instructions required to manufacture proteins. The oral cavity is one of the most accessible locations for the therapeutic intervention of gene therapy for several oral tissues. In 1990, the first significant trial of gene therapy was overseen to alleviate adenosine deaminase deficiency. The notion of genetic engineering has become increasingly appealing as a reflection of its benefits over conventional treatment modalities. An example of how this technology may alter dentistry is the implementation of gene therapy for dental and oral ailments. The objective of this article is to examine the effects of gene therapy on the field of dentistry, periodontology and implantology. Furthermore, the therapeutic factors of disease therapy, minimal invasion, and appropriate outcome have indeed been taken into consideration.

How Periodontitis or Periodontal Bacteria Can Influence Alzheimer's Disease Features? A Systematic Review of Pre-Clinical Studies

BACKGROUND

The negative effects of periodontitis on systemic diseases, including diabetes, cardiovascular diseases, and Alzheimer's disease (AD), have been widely described.

OBJECTIVE

This systematic review aimed to gather the current understanding of the pathophysiological mechanisms linking periodontitis to AD.

METHODS

An electronic systematic search of the PubMed/MEDLINE, Scopus, and Embase databases was performed using the following PECO question: How can periodontitis or periodontal bacteria influence Alzheimer's disease features?". Only preclinical studies exploring the biological links between periodontitis and AD pathology were included. This study was registered at the International Prospective Register of Systematic Reviews (PROSPERO), and the Syrcle and Camarades protocols were used to assess the risk of bias.

RESULTS

After a systematic screening of titles and abstracts (n = 3,307), thirty-six titles were selected for abstract reading, of which 13 were excluded (k = 1), resulting in the inclusion of 23 articles. Oral or systemic exposure to periodontopathogens or their byproducts is responsible for both in situ brain manifestations and systemic effects. Significant elevated rates of cytokines and amyloid peptides (Aβ) and derivate products were found in both serum and brain. Additionally, in infected animals, hyperphosphorylation of tau protein, hippocampal microgliosis, and neuronal death were observed. Exposure to periodontal infection negatively impairs cognitive behavior, leading to memory decline.

CONCLUSIONS

Systemic inflammation and brain metastatic infections induced by periodontal pathogens contribute to neuroinflammation, amyloidosis, and tau phosphorylation, leading to brain damage and subsequent cognitive impairment.

Antioxidant effect of spirulina in chronic periodontitis

BACKGROUND

Production of reactive oxygen species (ROS) by polymorpho nuclear neutrophils occurs in chronic periodontitis. These ROS are mainly involved in bacterial destruction. However, extracellular release of same results in destruction of surrounding tissue. Spirulina, a potent antioxidant when administered sub gingivally in pockets can offer improved results in chronic periodontitis patients. This study was conducted to evaluate the effect of Spirulina when delivered sub gingivally in patients with chronic periodontitis.

METHODS

Sixty chronic periodontitis patients were divided into 2 groups. Group I (n = 30) were treated with Scaling and Root planning (SRP) followed by placement of placebo (SRP-P) and in Group II (n = 30) Spirulina microspheres were placed sub gingivally (SRP-S) following SRP. Clinical parameters like bleeding on probing (BOP), clinical attachment level (CAL), gingival index (GI) and probing pocket depth (PPD) were evaluated. Levels of salivary and serum Malondialdehyde (MDA) were estimated using ultra violet spectrophotometer.

RESULTS

At baseline, in both groups there was no statistically significant difference in clinical and biochemical parameters. Intra group comparisons of parameters from baseline to 90 days were statistically significant in both groups. After 90 days difference in clinical parameters and salivary MDA levels were statistically significant in SRP-S compared to SRP-P group. Though serum MDA levels were reduced in both groups, they were not significant statistically.

CONCLUSIONS

Our study concluded that, local drug delivery of Spirulina adjunctive to SRP has potent antioxidant effect in treatment of chronic periodontitis.

Modifiable risk factors for the development and progression of periodontal tissue diseases

In this review, an analysis of modifiable risk factors for the development and progression of periodontal tissue diseases was carried out. The review highlights the data on the relationship of periodontal infection, tobacco smoking, diabetes mellitus, cardiovascular disease, drug-induced periodontal tissue damage, stress, and obesity with the risk of developing and progression of periodontal tissue diseases. A rather detailed analysis of the mechanisms of pathogenic influence of the microflora of the oral cavity, including in the subgingival plaque, was carried out. The mechanisms of the pathological effect of smoking on the state of periodontal tissues are described. Data on the effect of periodontal treatment on glycemic control in patients with diabetes mellitus are presented. The article emphasizes the importance of the presence of periodontal diseases as a risk factor for cardiovascular and cerebrovascular diseases, describes the mechanisms of the mutual influence of cardiovascular pathology and the inflammatory process in the periodontium. In addition, the article presents the possibilities of the iatrogenic effect of systemic drugs on the state of periodontal tissues. The data on the influence of stress loads on the development of dental diseases are presented. The review article describes in detail the mechanisms of influence of overweight and obesity on the risks of development and progression of periodontal tissue diseases. Based on the results of the scientific research publications presented in the article, it can be stated that not only the dentist, but also doctors of other specialties need to work to change the modifiable risk factors for the development and progression of periodontal diseases.

Plasma elaidic acid level is associated with periodontal health in American adults: A cross-sectional study

Background

Whether there is an association between TFAs and periodontitis is unclear. The purpose of this study was to investigate the relationship between moderate/severe periodontitis and plasma level of elaidic acid, a major trans-fatty acid component, in American adults.

Methods

The National Health and Nutrition Examination Survey (NHANES) years 2009-2010 were used to screen a total of 1,610 people. The independent variable of interest is plasma elaidic acid level, the dependent variable is periodontitis, and the covariates include socio-demographic variables, lifestyle variables, systemic diseases, etc. The distribution of variables in the covariate differences between the different independent groups according to tertile was investigated using a multiple linear regression model. To examine the association between plasma elaidic acid levels and moderate/severe periodontitis, three models were used.

Results

Multiple logistic regression analysis showed a significant association between plasma elaidic acid level and moderate/severe periodontitis after adjustment for potential confounders (OR = 1.021, 95%CI: 1.004-1.039, P = 0.01394). Subjects with the highest tertile of plasma elaidic acid levels were 51.9% more likely to have periodontitis compared with subjects with the lowest tertile of plasma elaidic acid levels (OR = 1.519, 95% CI: 1.136-2.030, P = 0.00477). No possible sources of heterogeneity were identified in the subgroup analyses.

Conclusion

Plasma elaidic acid levels are associated with periodontal disease in American adults.

Oral Microbiome in Pre-Rheumatoid Arthritis: The Role of Aggregatibacter Actinomycetemcomitans in Bacterial Composition

Rheumatoid arthritis (RA) is a chronic autoimmune disease that symmetrically affects the joints, eventually leading to cartilage and tissue destruction. While there are multiple etiologies for RA, from environmental to genetic risk factors, periodontal disease (PD) may contribute to the acceleration of RA symptoms in pre-rheumatoid arthritis (pre-RA) and RA patients. While PD is caused by multiple oral bacteria, this review explains the role of Aggregatibacter actinomycetemcomitans (Aa) in the pathogenesis of pre-RA and RA based on 13 primary articles. This paper focuses on the Aa virulence factor leukotoxin A (LtxA) because it has been reported to cause cellular destruction and inflammation in the oral cavity that can accelerate the development of RA. Individuals who are classified as pre-RA may benefit from periodontal screening to further reduce their risk of developing advanced RA. Additionally, they may benefit from earlier pharmacological therapy for RA using disease-modifying anti-rheumatic drugs (DMARD) and antibacterial treatment.

Risk of Periodontitis in Patients with Gastroesophageal Reflux Disease: A Nationwide Retrospective Cohort Study

Background: Gastroesophageal reflux disease (GERD) is the most common digestive clinical problem worldwide that affects approximately 20% of the adult populations in Western countries. Poor oral hygiene has been reported to be associated with GERD as an atypical clinical complication. However, evidence showing the relationship between GERD and the risk of periodontitis is less clear. The present study aimed to use a retrospective cohort study design to further clarify the association between GERD and the subsequent risk of periodontitis. Methods: The risk of periodontitis in patients with GERD was investigated by analyzing epidemiological data from the Taiwan National Health Insurance Research Database from 2008 to 2018. We selected 20,125 participants with a minimum age of 40 years in the GERD group and 1:1 propensity-matched these with non-GERD individuals by sex, age, and comorbidities. The incidence of periodontitis was determined at the end of 2018. A Cox proportional hazards regression model was used to evaluate the risk of periodontitis in patients with GERD. Results: The overall incidence rate of the periodontitis risk was 1.38-fold higher (30.0 vs. 21.7/1000 person years, adjusted hazard ratio (aHR) = 1.36, 95% confidence interval (CI) = 1.28−1.45) in patients with GERD than in those without GERD. After stratified analyses for sex, age, and comorbidity, patients with GERD had a higher risk of periodontitis for age (aHR = 1.31, 95% CI = 1.20−1.42 for 40−54 years and aHR = 1.42, 95% CI =1.28−1.57 for 55−69 years), sex (aHR = 1.40, 95% CI = 1.28−1.54 for men and aHR = 1.33, 95% CI = 1.23−1.45 for women), and presence (aHR = 1.36, 95% CI = 1.27−1.45) and absence (aHR = 1.40, 95% CI = 1.21−1.62) of comorbidity than those without GERD. Among the GERD cohort, the risk for periodontitis was increased with an increasing number of emergency room visits (≥ 1 vs. <1, aHR = 5.19, 95% CI = 2.16−12.5). Conclusions: Our results revealed that patients with GERD have a higher risk of periodontitis development than those without GERD. Clinicians should pay more attention to identifying and managing periodontitis in patients with GERD.

In vitro antibacterial effect of Pimpinella anisum essential oil on Enterococcus faecalis, Lactobacillus casei, Actinomyces naeslundii, and Aggregatibacter actinomycetemcomitans

INTRODUCTION

Pimpinellaanisum is a medicinal plant with antimicrobial, antifungal, and anti-oxidative properties. Limited studies have assessed the antibacterial properties of Pimpinellaanisum on oral and dental pathogens.

Photodynamic Therapy by Mean of 5-Aminolevulinic Acid for the Management of Periodontitis and Peri-Implantitis: A Retrospective Analysis of 20 Patients

Periodontitis and peri-implantitis are common in the population worldwide. Periodontal diseases affect approximately 50% of adults, while mucositis affects 80% of patients with implants, turning into peri-implantitis at a rate varying from 28 to 58%. If standardized treatments for all degrees and variety of periodontal diseases are known and codified, a consensus on the treatment of peri-implantitis still has to be found. Photodynamic therapy (PDT) has been used successfully in the medical field and was recently introduced as supportive therapy in dentistry. This paper reviews the results on 20 patients, 10 affected by periodontal disease (grades II to III) and 10 by peri-implantitis. Application of 5% 5-aminolevulinic acid gel (ALAD), as a support of causal therapy, in periodontal pockets and areas of peri-implantitis favored the maintenance of severely compromised teeth and significantly improved compromised implant conditions. Between baseline and 6 months, all teeth and implants remained functional. All patients confirmed that the scaling and root planning (SRP)+ALAD-PDT was not painful, and all perceived a benefit after the treatment at all timing points. For periodontal patients, a significant decrease in PPD after 3 (p < 0.001) and 6 months after SRP+ALAD-PDT respect baseline values were observed. For the implant patients, the SRP+ALAD-PDT was correlated to a decrease in PPD and BOP, and a slight increase in the number of exposed threads. However, the results were statistically significant only for PPD (p < 0.001).