Effect of Periodontitis and Periodontal Therapy on Oral and Gut Microbiota

Mounting evidence indicates that periodontitis-related oral bacteria may contribute to gut microbial dysbiosis. This clinical study aimed to explore the oral-gut microbial signatures associated with periodontitis and to longitudinally evaluate the effect of periodontal treatment on the oral and gut microbial composition. Stool and saliva samples from generalized stage III/IV periodontitis patients (n = 47) were collected and analyzed by 16S ribosomal RNA gene amplicon sequencing, before and 3 mo after steps I to II of periodontal therapy. Periodontally healthy matched subjects (n = 47) were used as controls. Principal component analysis was carried out to identify oral-gut microbial profiles between periodontitis patients at baseline and healthy subjects; periodontitis samples were longitudinally compared before and after treatment. β-Diversity of gut microbial profiles of periodontitis patients before treatment significantly differed from healthy controls (P < 0.001). Periodontal therapy was associated with a significant change in gut microbiota (P < 0.001), with post-treatment microbial profiles similar to healthy volunteers. A higher abundance of Bacteroides, Faecalibacterium, Fusobacterium, and Lachnospiraceae was noted in fecal samples of periodontitis patients at baseline compared to healthy controls. In contrast, Lactobacillus was the only genus more abundant in the latter. Additionally, periodontal therapy led to a parallel reduction in the salivary carriage of periodontal pathobionts, as well as gut Bacteroides, Lachnoclostridium, Lachnospiraceae, Oscillospiraceae, and Ruminococcaceae, to levels similar to healthy controls. Collectively, discriminating oral-gut microbial signatures of periodontitis were found. Periodontal treatment both mitigated oral dysbiosis and altered gut microbial composition, signifying potential broader implications for gastrointestinal health and disease.

Unraveling the Oral-Gut axis: Interconnection between Periodontitis and IBD, Current Challenges, and Future Perspective

As the opposite ends of the orodigestive tract, the oral cavity and the intestine share anatomical, microbial, and immunological ties that have bidirectional health implications. A growing body of evidence suggests an interconnection between oral pathologies and Inflammatory Bowel Disease (IBD), implying a shift from the traditional concept of independent diseases to a complex, reciprocal cycle. This review outlines the evidence supporting an "Oral-Gut" axis, marked by a higher prevalence of periodontitis and other oral conditions in IBD patients and vice versa. We present an in-depth examination of the interconnection between oral pathologies and IBD, highlighting the shared microbiological and immunological pathways, and proposing a "multi-hit" hypothesis in the pathogenesis of periodontitis-mediated intestinal inflammation. Furthermore, the review underscores the critical need for a collaborative approach between dentists and gastroenterologists to provide holistic oral-systemic healthcare.

Efficacy of a Solution Containing 33% Trichloroacetic Acid and Hydrogen Peroxide in Decontaminating Machined vs. Sand-Blasted Acid-Etched Titanium Surfaces

This in vitro study assessed the efficacy of a solution containing 33% trichloroacetic acid (CCl3COOH; TCA) and hydrogen peroxide (H2O2) in decontaminating machined (MAC) and sand-blasted acid-etched (SBAE) titanium surfaces. A total of 80 titanium disks were prepared (40 MAC and 40 SBAE). Streptococcus sanguinis and Enterococcus faecalis strains were incubated on 36 samples, while the remaining 44 were kept as controls. Roughness analysis and scanning electron microscopy were used to evaluate the surface features before and after TCAH2O2 treatment. The viability of human adipose-derived mesenchymal stem cells (ASCs) after TCAH2O2 decontamination was assessed with a chemiluminescent assay along with cell morphology through fluorescent staining. TCAH2O2 preserved the surface topography of MAC and SBAE specimens. It also effectively eradicated bacteria on both types of specimens without altering the surface roughness (p > 0.05). Also, no significant differences in protein adsorption between the pristine and TCAH2O2-treated surfaces were found (p = 0.71 and p = 0.94). While ASC proliferation remained unchanged on MAC surfaces, a decrease was observed on the decontaminated SBAE specimens at 24 and 48 h (p < 0.05), with no difference at 72 h (p > 0.05). Cell morphology showed no significant changes after 72 h on both surface types even after decontamination. This study suggests TCAH2O2 as a promising decontamination agent for titanium surfaces, with potential implications for peri-implant health and treatment outcomes.

Periodontitis and risk of cancer: Mechanistic evidence

This review aims to critically analyze the pathways of interaction and the pathogenic mechanisms linking periodontitis and oral bacteria with the initiation/progression of cancer at different body compartments. A higher risk of head and neck cancer has been consistently associated with periodontitis. This relationship has been explained by the local promotion of dysbiosis, chronic inflammation, immune evasion, and direct (epi)genetic damage to epithelial cells by periodontal pathobionts and their toxins. Epidemiological reports have also studied a possible link between periodontitis and the incidence of other malignancies at distant sites, such as lung, breast, prostate, and digestive tract cancers. Mechanistically, different pathways have been involved, including the induction of a chronic systemic inflammatory state and the spreading of oral pathobionts with carcinogenic potential. Indeed, periodontitis may promote low-grade systemic inflammation and phenotypic changes in the mononuclear cells, leading to the release of free radicals and cytokines, as well as extracellular matrix degradation, which are all mechanisms involved in carcinogenic and metastatic processes. Moreover, the transient hematogenous spill out or micro-aspiration/swallowing of periodontal bacteria and their virulence factors (i.e., lipopolysaccharides, fimbriae), may lead to non-indigenous bacterial colonization of multiple microenvironments. These events may in turn replenish the tumor-associated microbiome and thus influence the molecular hallmarks of cancer. Particularly, specific strains of oral pathobionts (e.g., Porphyromonas gingivalis and Fusobacterium nucleatum) may translocate through the hematogenous and enteral routes, being implicated in esophageal, gastric, pancreatic, and colorectal tumorigenesis through the modulation of the gastrointestinal antitumor immune system (i.e., tumor-infiltrating T cells) and the increased expression of pro-inflammatory/oncogenic genes. Ultimately, the potential influence of common risk factors, relevant comorbidities, and upstream drivers, such as gerovulnerability to multiple diseases, in explaining the relationship cannot be disregarded. The evidence analyzed here emphasizes the possible relevance of periodontitis in cancer initiation/progression and stimulates future research endeavors.

The co-occurrence of the two main oral diseases: periodontitis and dental caries

OBJECTIVES

Limited studies are available testing through multiple regression models the association between the two main oral diseases: dental caries and periodontitis. The aim of this cross-sectional population-based study was to verify whether dental caries and periodontitis co-occur in a representative sample of the South Korea population.

MATERIALS AND METHODS

A total of 23,405 subjects representative of 36.2 million of adults (KNHANES) were examined. Univariate and multiple regression analyses using 7 different models were applied, controlling for age, gender, smoking status, frequency of toothbrushing, use of interproximal toothbrushes and flossing, educational level, income, gum diseases treatment and tooth filling in the previous year, BMI, Vitamin D serum levels, alcoholism, diabetes status, stress and carbohydrates dietary intake.

RESULTS

In the fully adjusted model, participants with periodontitis had, respectively, a mean of 0.82 (95% CI: 0.41-1.23) and of 0.36 (95% CI: 0.22-0.50) more untreated decayed surfaces and teeth than participants without periodontitis, with an OR to have at least one untreated decayed surface of 1.96 (95% CI: 1.66-2.32). However, cumulative caries experience (DF scores) and periodontitis were not associated.

CONCLUSIONS

In this large nationally representative population, periodontitis and untreated dental caries co-occur. However, when considering cumulative caries experience (DF scores), the two diseases do not appear related.

CLINICAL RELEVANCE

In light of their possible co-occurrence, clinicians should implement integrative diagnostic, preventive and treatment strategies for both diseases.

Pocket closure after repeated subgingival instrumentation: a stress test to the EFP guideline for stage III-IV periodontitis

OBJECTIVES

To study the effects of one or two repeated subgingival instrumentations (RSI) in achieving the endpoints of therapy (EoT) in open pockets [residual probing pocket depth (PPD) ≥ 6 mm and PPD 4-5 mm with bleeding on probing (BoP)] after steps I-II of therapy.

MATERIALS AND METHODS

Twenty-five patients (3,552 total sites; 1,450 open pockets) with stage III-IV periodontitis received steps I-II of periodontal therapy and were re-evaluated after 4-6 weeks (T1). Residual pockets received RSI at T1 and at 3 months (T2). EoT (PPD < 4 or PPD < 6 BoP-) rate at T1, T2 and 6 months (T3) was computed. The number of needed surgeries and treatment costs were calculated.

RESULTS

At T1, 67.6% of open pockets achieved EoT. At residual PPD ≥ 6 mm at T1 (n = 172), one and two RSI resulted in 33.1% and 45.9% of EoT at T2 and T3, respectively. At residual PPD 4-5 mm with BoP at T1 (n = 298), one and two RSI resulted in 66.8% and 72.1% of EoT at T2 and T3, respectively. PPD at T1 predicted EoT after RSI in both cases, while tooth type only in residual PPD 4-5 mm BoP + . At T1, mean number of surgeries per patient and associated costs were significantly higher than after one/two RSI.

CONCLUSIONS

RSI may achieve EoT in residual PPD 4-5 mm BoP + and PPD ≥ 6 mm in a considerable number of cases.

CLINICAL RELEVANCE

These findings may support the administration of one/two cycles of RSI prior to surgical approach.

PROTOCOL REGISTRATION

ClinicalTrials.gov identification number: NCT04826926.

Denosumab and Zoledronic Acid Differently Affect Circulating Immune Subsets: A Possible Role in the Onset of MRONJ

This work investigated whether the anti-resorptive drugs (ARDs) zoledronic acid (Zol) and denosumab (Dmab) affect differently the levels of circulating immune cell subsets, possibly predicting the risk of developing medication-related ONJ (MRONJ) during the first 18 months of treatment. Blood samples were collected from 10 bone metastatic breast cancer patients receiving cyclin inhibitors at 0, 6, 12, and 18 months from the beginning of Dmab or Zol treatment. Eight breast cancer patients already diagnosed with MRONJ and treated with cyclin inhibitors and ARDs were in the control group. PBMCs were isolated; the trend of circulating immune subsets during the ARD treatment was monitored, and 12 pro-inflammatory cytokines were analyzed in sera using flow cytometry. In Dmab-treated patients, activated T cells were stable or increased, as were the levels of IL-12, TNF-α, GM-CSF, IL-5, and IL-10, sustaining them. In Zol-treated patients, CD8+T cells decreased, and the level of IFN-γ was undetectable. γδT cells were not altered in Dmab-treated patients, while they dramatically decreased in Zol-treated patients. In the MRONJ control group, Zol-ONJ patients showed a reduction in activated T cells and γδT cells compared to Dmab-ONJ patients. Dmab was less immunosuppressive than Zol, not affecting γδT cells and increasing activated T cells.

Influence of locally delivered doxycycline on the clinical and molecular inflammatory status of intrabony defects prior to periodontal regeneration: A double-blind randomized controlled trial

OBJECTIVES

To test the effect of locally delivered doxycycline (DOX) administered 2 weeks prior to minimally invasive periodontal regeneration in terms of presurgical inflammatory status and cytokine expression profile in the gingival crevicular fluid (GCF). Secondary aim was to assess the early wound healing index (EHI) at 2 weeks after surgery.

BACKGROUND

It is hypothesized that healing after periodontal regeneration is dependent on preoperative soft tissue condition, and that local antibiotics may improve the site-specific inflammatory status at short time.

METHODS

Sites associated with periodontal intrabony defects requiring regenerative surgery and showing bleeding on probing (BoP) were included. At T0, experimental sites were randomly treated with subgingival instrumentation with or without topic DOX application. After 2 weeks (T1), defects were approached by means of minimally invasive surgical technique. GCF was sampled at both T0 and T1 for inflammatory biomarker analysis. Two weeks after surgery, the EHI was evaluated (T2).

RESULTS

Forty-four patients were included. At T1, the number of BoP+ sites was statistically significantly less in the test group (27.3% vs. 72.7%; p < .01). The total amount of interleukin (IL)-1β (p < .001), matrix-metalloproteinases (MMP)-8 (p < .001), and MMP-9 (p = .010) in the GCF significantly decreased in the test group at T1, with relevant differences compared to controls. At T2, the EHI had an average value of 1.45 ± 0.86 in the test group while in the control, it was 2.31 ± 1.43 (p = .027). A statistically significantly positive correlation was observed between the amount of IL-1β and MMP-9 and EHI scores.

CONCLUSIONS

Within the limitations of this study, sites treated with DOX showed improved clinical and molecular inflammatory parameters before surgery, as well as soft tissue healing 2 weeks after surgery.

The Gum-Gut Axis: Periodontitis and the Risk of Gastrointestinal Cancers

Periodontitis has been linked to an increased risk of various chronic non-communicable diseases, including gastrointestinal cancers. Indeed, dysbiosis of the oral microbiome and immune-inflammatory pathways related to periodontitis may impact the pathophysiology of the gastrointestinal tract and its accessory organs through the so-called "gum-gut axis". In addition to the hematogenous spread of periodontal pathogens and inflammatory cytokines, recent research suggests that oral pathobionts may translocate to the gastrointestinal tract through saliva, possibly impacting neoplastic processes in the gastrointestinal, liver, and pancreatic systems. The exact mechanisms by which oral pathogens contribute to the development of digestive tract cancers are not fully understood but may involve dysbiosis of the gut microbiome, chronic inflammation, and immune modulation/evasion, mainly through the interaction with T-helper and monocytic cells. Specifically, keystone periodontal pathogens, including Porphyromonas gingivalis and Fusobacterium nucleatum, are known to interact with the molecular hallmarks of gastrointestinal cancers, inducing genomic mutations, and promote a permissive immune microenvironment by impairing anti-tumor checkpoints. The evidence gathered here suggests a possible role of periodontitis and oral dysbiosis in the carcinogenesis of the enteral tract. The "gum-gut axis" may therefore represent a promising target for the development of strategies for the prevention and treatment of gastrointestinal cancers.

Senescent Markers Expressed by Periodontal Ligament-Derived Stem Cells (PDLSCs) Harvested from Patients with Periodontitis Can Be Rejuvenated by RG108

Periodontal ligament (PDL) has become an elective source of mesenchymal stem cells (PDLSCs) in dentistry. This research aimed to compare healthy PDLSCs (hPDLSCs) and periodontitis PDLSCs (pPDLSCs) to ascertain any possible functional differences owing to their milieux of origin. Cells were tested in terms of colony-forming unit efficiency; multi differentiating capacity; immunophenotype, stemness, and senescent state were studied by flow cytometry, immunofluorescence, and β-galactosidase staining; gene expression using RT-PCR. Both hPDLSCs and pPDLSCs were comparable in terms of their immunophenotype and multilineage differentiation capabilities, but pPDLSCs showed a senescent phenotype more frequently. Thus, a selective small molecule inhibitor of DNA methyltransferase (DNMT), RG108, known for its effect on senescence, was used to possibly reverse this phenotype. RG108 did not affect the proliferation and apoptosis of PDLSCs, and it showed little effect on hPDLSCs, while a significant reduction of both p16 and p21 was detected along with an increase of SOX2 and OCT4 in pPDLSCs after treatment at 100 μM RG108. Moreover, the subset of PDLSCs co-expressing OCT4 and p21 decreased, and adipogenic potential increased in pPDLSCs after treatment. pPDLSCs displayed a senescent phenotype that could be reversed, opening new perspectives for the treatment of periodontitis.

One-Year Outcomes of Subcrestal Platform-Switched Implants With and Without Sterile Prosthetic Abutments: A Randomized Controlled Trial

Surface contaminants on customized implant abutments could trigger inflammatory response in the peri-implant tissues. The aim of this randomized controlled study was to assess the radiographic bone changes around implants restored with customized, platform-switched abutments, with and without autoclave treatment, 12 months after definitive restoration. Dental implants were placed 1 mm subcrestally in 64 systemically healthy patients (mean age 63.3 ± 10.0 years, 31 with history of periodontitis) to replace single or multiple missing teeth. According to a randomization list, abutments were subjected to steam and autoclave sterilization (43 implants, test group) or steam cleaning alone (44 implants, control group). Periapical standardized radiographs were taken at the time of implant insertion, prosthetic abutment connection and 12 months after definitive cement-retained restoration. All implants were clinically stable without any sign of infection at the 12-month follow-up. An average marginal bone loss of 0.25 ± 0.19 mm was found in the test group compared to 0.35 ± 0.23 mm in the control group without statistically significant difference, while the percentage of bleeding sites was significantly higher in the control group (8.7 ± 13.1% versus 19.1 ± 19.8%, P = .035). Autoclave treatment of customized abutments would seem to reduce the inflammatory response around subcrestally placed implants.

Unraveling the Link between Periodontitis and Inflammatory Bowel Disease: Challenges and Outlook

Periodontitis and Inflammatory Bowel Disease (IBD) are chronic inflammatory conditions, characterized by microbial dysbiosis and hyper-immunoinflammatory responses. Growing evidence suggest an interconnection between periodontitis and IBD, implying a shift from the traditional concept of independent diseases to a complex, reciprocal cycle. This review outlines the evidence supporting an "Oral-Gut" axis, marked by a higher prevalence of periodontitis in IBD patients and vice versa. The specific mechanisms linking periodontitis and IBD remain to be fully elucidated, but emerging evidence points to the ectopic colonization of the gut by oral bacteria, which promote intestinal inflammation by activating host immune responses. This review presents an in-depth examination of the interconnection between periodontitis and IBD, highlighting the shared microbiological and immunological pathways, and proposing a "multi-hit" hypothesis in the pathogenesis of periodontitis-mediated intestinal inflammation. Furthermore, the review underscores the critical need for a collaborative approach between dentists and gastroenterologists to provide holistic oral-systemic healthcare.

Effect of post-surgical flap position on soft tissue regrowth and keratinized tissue increase following fibre retention osseous resective surgery: a 6-month randomized study with multilevel analysis

BACKGROUND

The aim of this randomized split-mouth study was to assess the influence of primary flap position on the amount of coronal soft tissue regrowth and keratinized tissue (KT) 6 months after osseous resective surgery with fiber retention technique (FibReORS).

MATERIALS AND METHODS

Two contralateral posterior sextants in 16 patients were treated with FibReORS and randomly assigned to flap positioning either 2 mm below the bone crest (apical group) or at the level of bone crest (crestal group). Clinical parameters were recorded at 1, 3 and 6 months and patient-related outcomes during the first two post-operative weeks.

RESULTS

Healing period was uneventful. Patient's discomfort was similar in both groups. The overall soft tissue rebound was higher in the apical than in the crestal group (2.0 ± 1.3 mm versus 1.3 ± 0.7 mm), but the difference was statistically significant only interproximally (2.2 ± 1.3 mm versus 1.6 ± 0.8 mm). Multilevel analyses showed higher soft tissue rebound in sites with normal compared to thin phenotype (1.5 mm, p < 0.0001) and treated with flap positioned 2 mm apically to the bone crest (0.7 mm, p < 0.001). An additional 0.5 mm KT increase was observed at interdental sites in the apical group.

CONCLUSIONS

Apical flap positioning increases soft tissue rebound and KT width, mainly at the interdental sites, with reduced patient discomfort.

TRIAL REGISTRATION

The trial was registered at ClinicalTrials.gov (ID: NCT05140681, Registration date: 1/12/2021, retrospectively registered).

Pocket closure in stage III-IV grade C periodontitis: A multilevel analysis following non-surgical periodontal therapy

BACKGROUND

Risk of disease progression and tooth loss is higher in cases where deep probing pocket depths (PPDs) and bleeding on probing (BOP) persist after active periodontal treatment. This study aimed to investigate the efficacy of non-surgical periodontal therapy on pocket closure (PC), defined as PPD ≤4 mm without BOP (PC1) or PPD ≤4 mm solely (PC2) 3 months after non-surgical periodontal treatment and to compare PC between smokers and non-smokers.

METHODS

This cohort study is a secondary analysis from a controlled clinical trial consisting of systemically healthy patients with stage III or IV grade C periodontitis. All the sites with baseline PPD ≥5 mm are included as diseased sites and PC at 3 months after completion of non-surgical periodontal treatment was calculated. PC was compared between smokers and non-smokers at site and patient levels. Multilevel analysis is used to investigate factors at patient, tooth and site levels affecting PPD changes and the probability of PC.

RESULTS

A total of 1998 diseased sites in 27 patients were included in the analysis. The rates of PC1 and PC2 were 58.4% and 70.2% and were significantly correlated to smoking habits at site level (r (1) = 7.03, p = 0.008; r (1) = 36.17, p < 0.001). Tooth type, mobility, clinical attachment level (CAL) and PPD at baseline significantly affected PC.

CONCLUSIONS

The present findings indicate that non-surgical periodontal treatment is effective in PC, but its performance is influenced by baseline PPD and CAL and residual pockets may remain.

Periodontitis and low cognitive performance: A population-based study

AIM

To study the epidemiological association between periodontitis and low cognitive performance among older adults, within a representative sample of the U.S.

POPULATION

MATERIALS AND METHODS

Data from 2086 older adults (≥60 years old), representative of 77.1 million people, were retrieved from the NHANES 2011-2014 database. Periodontitis cases were identified and classified according to the AAP/CDC criteria (mild, moderate, and severe). Cognitive function was assessed through the Consortium to Establish a Registry for Alzheimer's disease (CERAD), the animal fluency test (AFT), the digit symbol substitution test (DSST), and the global cognition score. The lowest non-survey weighted quartile for each cognitive test was defined as low cognitive performance. Simple and multiple regression analyses were performed.

RESULTS

Moderate and severe periodontitis were significantly associated with a low DSST performance (OR = 1.66 and OR = 2.97, respectively). Each millimetre increase in mean CAL was associated with a lower AFT (OR = 1.44), DSST (OR = 1.86), and global cognition (OR = 1.50) performance.

CONCLUSIONS

The findings of the present study suggest the existence of an independent association between periodontitis and low cognitive performance among older adults (≥60 years old).

Effect of psychosocial stress and coping strategies on non-surgical periodontal therapy in patients with generalized stage III/IV periodontitis: a longitudinal intervention study

OBJECTIVES

The aim of this longitudinal intervention study was to assess the impact of psychosocial stress and coping response strategies on the clinical outcomes in periodontitis patients treated with non-surgical periodontal therapy (NSPT).

MATERIALS AND METHODS

After the administration of psychological questionnaires, patients diagnosed with generalized stage III-IV periodontitis were categorized into different groups depending on their stress levels (10-item perceived stress level (PSS-10)) and coping response strategies (coping responses inventory (CRI)). Clinical data were collected 1 week before and 3 months after the completion of NSPT.

RESULTS

Of the 90 patients included at baseline, 27 presented major and 63 minor stress levels, while 40 had avoidance and 50 approach coping behavior. All clinical parameters were similar at the baseline across different categories. At re-evaluation, full-mouth bleeding score (FMBS), mean probing pocket depth (PPD), and number of residual pathological pockets were significantly superior in groups with higher stress levels (p <0.001, p =0.001, and p =0.020, respectively), while higher full-mouth plaque scores (FMPS) and FMBS were found in patients with avoidance coping strategies (p =0.009 and p <0.001, respectively). When jointly evaluated, an added detrimental effect of coping styles on allostatic load was observed. Multivariate analysis confirmed a significant effect of stress levels and coping strategies on final FMBS, but not of coping on mean PPD.

CONCLUSION

Psychosocial stress and avoidance coping strategy seem to negatively influence the clinical outcomes of NSPT at short term (NCT04739475; 9/1/2017).

PRACTICAL IMPLICATIONS

Based on these findings, patients reflecting these psychological profiles should be considered at greater risk for poor NSPT response and may benefit from complementary stress management strategies.

Periodontitis prevalence and severity in inflammatory bowel disease: A case-control study

BACKGROUND

Recent evidence is supporting the notion of a microbiological and immunological continuum on the gum-gut axis in health and disease. Therefore, the purpose of this study was to assess the prevalence and risk indicators of periodontitis in patients with Crohn's disease (CD) or ulcerative colitis (UC) compared to age- and sex-matched controls without inflammatory bowel disease (IBD).

METHODS

A total of 180 IBD (117 CD, 60 UC, 3 IBD-unclassified) and 180 healthy controls were compared for their periodontitis diagnosis (Centers for Disease Control and Prevention/American Academy of Periodontology [CDC/AAP] case definition) and full-mouth periodontal parameters. In addition, explorative logistic regression models were performed.

RESULTS

Significantly more patients with IBD had moderate/severe periodontitis (85.6% vs. 65.6%, p < 0.001) and severe periodontitis (36.7% vs. 25.6%, p < 0.001) than controls. Differences were higher in the 35-50 and 51-65 age groups, without significant changes between CD and UC. IBD subjects presented chances ∼3.5 higher of having moderate/severe periodontitis (p < 0.001). Significant variables associated with periodontitis in the whole sample were older age, presence of IBD, and higher full-mouth plaque scores, whereas in the IBD group they were male sex, IBD-associated surgery, and IBD duration and localization (pancolitis). Positive risk indicators for IBD were periodontitis severity and higher bleeding scores, while smoking was negatively associated with UC.

CONCLUSIONS

Relevant associations between IBD and periodontitis were found, being modified by CD and UC clinical characteristics. Preventive and therapeutic strategies involving the gum-gut axis should be enforced in IBD patients.

Leisure-time and occupational physical activity demonstrate divergent associations with periodontitis: A population-based study

AIM

To evaluate the association between leisure-time/occupational physical activity (LTPA/OPA) and periodontitis in a nationally representative sample of the U.S.

POPULATION

MATERIALS AND METHODS

Data from 10,679 adults were retrieved from NHANES 2009-2014 database. Physical activity was assessed through the Global Physical Activity Questionnaire, and accordingly, subjects were classified as performing either high or low LTPA/OPA. Periodontal status was assessed through a full-mouth periodontal examination, and subjects were classified according to the AAP/CDC criteria (no, mild, moderate, or severe periodontitis). Simple and multiple regression analyses were applied to study the association between LTPA/OPA and periodontitis/severe periodontitis.

RESULTS

Multiple regression analyses identified high LTPA as a protective indicator for periodontitis (odds ratio [OR] = 0.81; 95% confidence interval [CI]: 0.72-0.92), while high OPA was found to be a significant risk indicator (OR = 1.16; 95% CI: 1.04-1.30). The combination low LTPA/high OPA showed a cumulative independent association with periodontitis (OR = 1.47; 95% CI: 1.26-1.72). Moreover, both high LTPA (OR = 0.72; 95% CI: 0.58-0.90) and high OPA (OR = 1.29; 95% CI: 1.09-1.53) were significantly associated with stronger estimates of severe periodontitis; the same was observed for the combination of low LTPA/high OPA (OR = 1.66; 95% CI: 1.29-2.15).

CONCLUSIONS

LTPA and OPA showed divergent associations with periodontitis.

Effect of sub-marginal instrumentation before surgical treatment of peri-implantitis: A multi-centre randomized clinical trial

AIM

The present multi-centre randomized clinical trial with 12 months of follow-up aimed at studying the added effect of sub-marginal instrumentation before surgical treatment of peri-implantitis.

MATERIALS AND METHODS

Forty-two patients diagnosed with peri-implantitis were recruited. After a behavioural intervention phase including oral hygiene instructions, patients were randomized to either receiving supra- and sub-marginal instrumentation on their affected implants (control group: 21 patients and 29 implants) or only supra-marginal instrumentation (test group: 21 patients and 24 implants), before undergoing surgery. Changes in the deepest probing pocket depth (PPD) with respect to baseline and a composite outcome of treatment success (no implant loss, no bone loss &gt; 0.5 mm, no bleeding or suppuration on probing [BoP/SoP], and PPD ≤ 5 mm) at the 12-month examination were regarded as the primary outcomes of the trial.

RESULTS

At the 12-month examination, changes in the deepest PPD with respect to baseline amounted to -2.96 mm in the control group and to -3.11 mm in the test one (MD = -0.16; SE = 0.56; p = .769), while 21.4% of the implants in the control group and 33.3% in the test group presented treatment success (OR = 1.83; SE = 1.15; p = .338). With the exception of a longer non-surgical treatment duration in the control group (differences in  = -14.29 min; SE = 2.91; p &lt; .001), no other secondary (e.g., soft-tissue recession, keratinized mucosa height, and bone level changes, as well as BoP, SoP, profuse bleeding and implant loss rates) or exploratory (i.e., early wound healing, aesthetics, surgical and total treatment duration, surgery difficulty, intra-operative bleeding, and adverse events) outcome demonstrated statistically significant differences between groups.

CONCLUSIONS

The present multi-centre randomized clinical trial did not demonstrate an added effect of performing sub-marginal instrumentation 6 weeks before the surgical treatment of peri-implantitis. Larger clinical trials are however needed to confirm the present findings (Clinicaltrials.gov: NCT03620331).

Surface decontamination protocols for surgical treatment of peri-implantitis: A systematic review with meta-analysis

OBJECTIVE

To answer the following PICO question: "In patients requiring surgical treatment of peri-implantitis (P), is any implant surface decontamination protocol (I) superior to others (C) in terms of clinical and radiographic parameters (O)?"

METHODS

Randomized clinical trials (RCTs) comparing two or more decontamination protocols as part of the surgical treatment of peri-implantitis were included. Two authors independently searched for eligible studies, screened titles and abstracts, did full-text analysis, extracted data, and performed the risk-of-bias assessment. Whenever possible, results were summarized through random effects meta-analyses.

RESULTS

Twenty-two manuscripts reporting on 16 RCTs were included, testing mechanical, chemical and physical decontamination protocols. All of them resulted in an improvement in clinical parameters; however, the superiority of specific protocols over others is mainly based on single RCTs. The use of titanium brushes and implantoplasty showed favorable results as single decontamination methods. Meta-analyses indicated a lack of added effect of Er:Yag laser on probing pocket depth (PPD) reduction (n = 2, WMD = -0.24 mm, 95% confidence interval [CI] [-1.10; 0.63], p = .59); while systemic antimicrobials (amoxicillin or azithromycin) showed an added effect on treatment success ([PPD ≤5 mm, no bleeding or suppuration, no progressive bone loss]; n = 2, RR = 1.84, 95% CI [1.17;2.91], p = .008), but not in terms of PPD reduction (n = 2, WMD = 0.93 mm, 95% CI [-0.69; 2.55], p = .26), even if with substantial heterogeneity.

CONCLUSIONS

No single decontamination method demonstrated clear evidence of superiority compared to the others. Systemic antibiotics, but not Er:Yag laser, may provide short-term clinical benefits in terms of treatment success (CRD42020182303).

Comparison of Different Chemical and Mechanical Modalities for Implant Surface Decontamination: Activity against Biofilm and Influence on Cellular Regrowth—An In Vitro Study

Objectives

The aim of this in vitro study was to compare the efficacy of chemical and mechanical methods for decontamination of titanium dental implant surfaces previously infected with polymicrobial biofilms in a model simulating a peri-implant defect. Furthermore, the effect of each decontamination protocol on MG-63 osteoblast-like cells morphology and adhesion to the treated implants was assessed.

Background

Peri-implantitis is a growing issue in dentistry, and evidence about implant surface decontamination procedures is lacking and inconclusive.

Methods

A total of 40 previously biofilm-contaminated implants were placed into a custom-made model simulating a peri-implant defect and randomly assigned to five treatment groups: (C) control (no treatment); (AW) air abrasion without any powder; (ESC) air abrasion with powder of erythritol, amorphous silica, and 0.3% chlorhexidine; (HBX) decontamination with a sulfonic/sulfuric acid solution in gel; and (HBX + ESC) a combination of HBX and ESC. Microbiological analysis was performed on five implants per treatment group, and the residual viable bacterial load measured in log 10 CFU/mL was counted for each bacterial strain and for the total number of colonies. The remaining three implants per group and three noncontaminated (NC) implants were used to assess surface biocompatibility using a scanning electron microscope and a backscattered electron microscope after seeding with MG-63 cells.

Results

A significant decontaminant effect was achieved using HBX or HBX + ESC, while no differences were observed among other groups. The percentage of implant surface covered by adherent MG-63 cells was influenced by the treatment method. Progressive increases in covered surfaces were observed in groups C, AW, ESC, HBX, HBX + ESC, and NC.

Conclusions

A combination of mechanical and chemical decontamination may provide more predictable results than mechanical cleaning alone.

Periodontitis and COVID-19: Biological Mechanisms and Meta-analyses of Epidemiological Evidence

Since the beginning of 2020, the entire global health care system has been severely challenged by the outbreak of coronavirus 2019 disease (COVID-19). Robust evidence has demonstrated a more severe course of COVID-19 in the presence of several comorbidities, such as cardiovascular diseases, diabetes mellitus, and obesity. Here, we critically appraise the recent research discoveries linking periodontitis to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and to severe COVID-19, with a special focus on the associated biological mechanisms and the available epidemiological evidence. SARS-CoV-2 main receptors and coreceptors (ACE2, TMPRSS2, furin, CD147) are overexpressed in periodontal tissues of periodontitis patients, with inflammation, periodontal pathogens, and damage-induced pyroptosis triggering a positive feedback loop. However, meta-analyses of epidemiological studies only indicated a nonstatistically significant tendency for an increased risk of SARS-CoV-2 infection in subjects with periodontitis (odds ratio [OR] = 1.69; 95% CI, 0.91-3.13, P = 0.09). Furthermore, periodontitis may worsen clinical COVID-19 courses through multiple direct and indirect pathways, including damage to lower airways due to aspiration of periodontal pathogens, exacerbation of the cytokine storm via the low-grade chronic systemic inflammation, and SARS-CoV-2 dissemination through the ulcerated gingival epithelium with consequent induced pulmonary vessels vasculopathy. Indeed, meta-analyses of epidemiological studies indicated that periodontitis subjects are more likely to experience a more severe course of COVID-19. Specifically, periodontitis was associated with a 4-fold increased odds of hospitalization (OR = 4.72; 95% CI, 1.11-20.03, P = 0.04), 6-fold of requiring assisted ventilation (OR = 6.24; 95% CI, 2.78-14.02, P = 0.00), and more than 7-fold of death due to COVID-19 complications (OR = 7.51; 95% CI, 2.16-26.10, P = 0.00). The breakthrough analyzed here emphasizes the relevance of the mouth-systemic connection as a target to mitigate the current COVID-19 emergency and the future predicted coronavirus pandemics.

Estimates and multivariable risk assessment of mid-buccal gingival recessions in an Italian adult population according to the 2018 World Workshop Classification System

OBJECTIVES

The aim of this cross-sectional study was to provide estimate of mid-buccal gingival recession (GR) according to the 2018 World Workshop Classification System and to explore GR risk indicators in a representative urban population in North-West of Italy.

MATERIAL AND METHODS

This is a secondary analysis using data collected in an epidemiological study enrolling a representative sample of 736 adults, living in Turin. GR prevalence was defined as the presence of at least one mid-buccal GR ≥ 1 mm. GRs were categorized according to the 2018 classification system (RT1, RT2, RT3) and to different severity cutoffs. Logistic regression analysis was performed to identify RT GR risk indicators.

RESULTS

Mid-buccal GR ≥ 1 mm affected 57.20% of subjects and 14.56% of teeth. When considering RT1 GRs, their prevalence was 40.90% and 6.29% at the patient and tooth level. RT2 and RT3 GRs affected 25.82% and 36.68% of the study population, respectively. RT1 GRs occurred mostly on maxillary and mandibular premolars and maxillary canines, while RT2 and RT3 GRs on maxillary molars and mandibular incisors. Older age, high education, and full-mouth plaque score (FMPS) < 30% were risk indicators for RT1 GRs, while older age, poor education, periodontitis, and FMPS > 60% were significant contributors to RT2 and RT3 GRs.

CONCLUSIONS

RT1 and RT3 are fairly common findings in this Italian population and are significantly associated to different contributing factors and tooth type distribution pattern.

CLINICAL RELEVANCE

Prevention strategies should target different socio-demographic, behavioral, and clinical risk indicators based on the RT classes.

Comparing Ionic Profile of Gingival Crevicular Fluid and Saliva as Distinctive Signature of Severe Periodontitis

Although increasing evidence is emerging on the contribution of chemical elements in periodontal health, no studies have concomitantly evaluated the ionic profile in gingival crevicular fluid (GCF) and saliva in relation to the underlying periodontal status. Our hypothesis is that these biofluids have distinctive ionic content. Therefore, the aim of this cross-sectional study was to analyze the elemental composition of GCF and saliva in order to explore which biological matrix and which combination of elements could discriminate between periodontitis and periodontal health. Twelve ions were analyzed in GCF and unstimulated saliva from 54 subjects (18 periodontally healthy, 18 untreated severe periodontitis and 18 treated severe periodontitis) using inductively coupled plasma–mass spectrometry (ICP-MS) and inductively coupled plasma–optical emission spectroscopy (ICP-OES). These analytical techniques were able to determine levels of sodium (Na), potassium (K), calcium (Ca) and magnesium (Mg), while the other elements were below the detection threshold. Na and K ions were detected at elevated concentration in untreated periodontitis compared with treated periodontitis and healthy periodontium. Ca was increased in untreated periodontitis, but the difference was not significant. In saliva, only Na was significantly associated with periodontitis. The combination of Na and K in GCF enabled the correct assignment of a subject to the periodontitis or healthy group. Based on these preliminary results, GCF demonstrated higher clustering potential than saliva.

Macro and trace elements signature of periodontitis in saliva: A systematic review with quality assessment of ionomics studies

Objectives

The present systematic review examined the available evidence on distinctive salivary ion profile in periodontitis compared to periodontal health and provided a qualitative assessment of the literature.

Background

Macro and trace elements are essential for cellular physiology, and their changes in biological fluids can be revelatory of an underlying pathological status.

Methods

Data from relevant studies identified from PubMed, Embase, and Scopus databases were retrieved to answer the following PECO question: “In systemically healthy individuals, are there any differences in any salivary macro or trace element concentration between periodontally healthy subjects (H) and patients with periodontitis (P)?” Quality of included studies was rated using a modified version of the QUADOMICS tool. A consistency analysis was performed to identify significantly discriminant chemical elements.

Results

After the screening of 873 titles, 13 studies were included reporting data on 22 different elements. Among them, levels of sodium and potassium were consistently and significantly higher in P compared to H. Conflicting results were found for all the other elements, despite concentration of calcium, copper, and manganese mostly increased in saliva of P. Levels of magnesium were found higher in P than in H in 2 studies but lower in 3. Zinc resulted significantly increased in saliva from H compared to P individuals in 2 studies, but one study reported opposite results. Four studies were considered as high quality, while reporting of operative protocols and statistical analysis was a major limitation for the others. Due to high methodologic heterogeneity, meta‐analysis was not performed.

Conclusions

Levels of macro or trace elements were differentially identified in saliva across diverse periodontal conditions, having a major potential for investigation of oral homeostasis and for high‐resolution periodontal diagnosis. Products of inflammatory physiologic cellular impairment, such as sodium and potassium, were the most consistently associated with periodontitis (PROSPERO CRD42021235744).

Periodontitis and Accelerated Biological Aging: A Geroscience Approach

As the whole world is epidemically aging, the burden of periodontitis and tooth loss is becoming a major health concern. Growing meta-epidemiological data implicate chronic systemic inflammation/infection due to periodontitis as an independent risk factor for aging-related diseases and mortality. However, because people age differently, chronological age is not a reliable marker of an individual's functional status. Recent advances in geroscience have shown that various biomarker signatures of biological aging are longitudinally associated with declined physical function, morbidity, and mortality due to major age-related diseases, including periodontitis. Here, we emphasize novel research developments bidirectionally linking periodontitis to accelerated biological aging. Using a composite biomarker age estimator, a striking increase in periodontitis and tooth loss was observed in subjects whose biological age at baseline was higher than their chronological age. Moreover, significantly shortened telomeres were encountered in populations affected by severe periodontitis. Second, we elucidate the cellular and molecular pillars of the aging process at the periodontal level. Accumulating evidence suggests that cellular senescence, stem cell exhaustion, and immunoaging are hallmarks of biological aging implicated in the impairment of periodontal homeostasis and the pathophysiology of periodontitis. Indeed, persistent bacteria-derived lipopolysaccharide stimulation influences cellular senescence in osteocytes, driving alveolar bone resorption. Moreover, inflammaging status induced by chronic hyperglycemia elevates the burden of senescent cells in gingival tissues, impairing their barrier function. Lastly, we reviewed a recent breakthrough in senotherapy to directly target the mechanisms of aging at the periodontal level. Physical exercise and intermittent fasting, together with natural compounds, senolytic drugs, and cell therapy, are increasingly being evaluated to rejuvenate the oral cavity. Following these innovations in geroscience, further advancements could provide oral clinicians the chance to intercept biological aging when still "subclinical" and set interventions for halting or delaying the trajectory toward aging-related diseases while patients are still chronologically young.

Pocket closure and residual pockets after non-surgical periodontal therapy: A systematic review and meta-analysis

Aim

To analyse the efficacy of non‐surgical therapy (NST) in terms of pocket closure (PC) and changes in percentage and number of pockets.

Materials and Methods

Three databases (PubMed, EMBASE, and Scopus) were searched up to January 2020. Prospective studies with a minimum follow‐up of 12 months and presenting data in terms of PC or number or percentage of pocket depths (PDs) before and after NST on systemically healthy patients were included. Random‐effect meta‐analyses were performed.

Results

After screening 4610 titles and abstracts, 27 studies were included. Of these, 63.9% of PC was reported by one study. The percentage of PDs ≤3 mm changed from 39.06% to 64.11% with a weighted mean difference (WMD) of 26.14% (p < .001). This accounted for a relative increase of healthy sites of 64.13%. The mean percentage of PD ≥5 mm was 28.23% and 11.71% before and after treatment, respectively, with a WMD of 15.50% (p < .001). The WMD in the number of PDs ≥5 mm before and after treatment was 24.42 (p = .036). The mean number of residual PPD ≥5 after NST was 14.13.

Conclusions

NST is able to eradicate the majority of the pockets. However, residual pockets after NST may remain and should be considered cautiously for further treatment planning.

Bidirectional Association between Metabolic Control in Type-2 Diabetes Mellitus and Periodontitis Inflammatory Burden: A Cross-Sectional Study in an Italian Population

This study assessed the periodontal conditions of type 2 diabetes (T2DM) patients attending an Outpatient Center in North Italy and explored the associations between metabolic control and periodontitis. Periodontal health of 104 T2DM patients (61 men and 43 women, mean age of 65.3 ± 10.1 years) was assessed according to CDC/AAP periodontitis case definitions and Periodontal Inflamed Surface Area (PISA) Index. Data on sociodemographic factors, lifestyle behaviors, laboratory tests, and glycated hemoglobin (HbA1c) levels were collected by interview and medical records. Poor glycemic control (HbA1c ≥ 7%), family history of T2DM, and C-reactive protein levels were predictors of severe periodontitis. An increase in HbA1c of 1% was associated with a rise in PISA of 89.6 mm². On the other hand, predictors of poor glycemic control were severe periodontitis, waist circumference, unbalanced diet, and sedentary lifestyle. A rise in PISA of 10 mm² increased the odds of having HbA1c ≥ 7% by 2%. There is a strong bidirectional connection between periodontitis and poor glycemic control. The inflammatory burden posed by periodontitis represents the strongest predictor of poor glycemic control.

Pocket resolution in regenerative treatment of intrabony defects with papilla preservation techniques: A systematic review and meta-analysis of randomized clinical trials

AIM

To systematically assess the clinical performance of different approaches for periodontal regeneration of intrabony defects in terms of pocket resolution compared to access surgery with papilla preservation techniques (PPTs).

MATERIAL AND METHODS

Systematic literature searches were conducted on PubMed, EMBASE, and CENTRAL up to April 2020 to identify RCTs on regenerative treatment [guided tissue regeneration (GTR) or enamel matrix derivative (EMD) with or without biomaterials] of intrabony defects using PPTs. Results were expressed as weighted mean percentages (WMP) or risk ratios of pocket resolution at 12 months (considering both final PD ≤ 3 mm and ≤4 mm).

RESULTS

A total of 12 RCTs were included. Based on a final PD ≤ 3 mm or PD ≤ 4 mm, the WMP of pocket resolution was 61.4% and 92.1%, respectively. EMD and GTR obtained comparable results. Pairwise meta-analysis identified a greater probability of achieving pocket resolution for GTR compared to PPTs. The number needed to treat for GTR to obtain one extra intrabony defect achieving PD ≤ 3 mm or PD ≤ 4 mm over PPTs was 2 and 4, respectively.

CONCLUSION

Regenerative surgery represents a viable approach to obtain final PD ≤ 4 mm in the short-term.

Metabolomics of gingival crevicular fluid to identify biomarkers for periodontitis: A systematic review with meta-analysis

The present systematic review aimed to examine periodontitis-specific biomarkers in the gingival crevicular fluid (GCF) that could have a diagnostic relevance, and to provide a qualitative assessment of the current literature. Metabolites are reliable indicators of pathophysiological statuses, and their quantification in the GCF can provide an outlook of the changes associated with periodontitis and have diagnostic value. Relevant studies identified from PubMed, Embase, Cochrane Library, and Scopus databases were examined to answer the following PECO question: "In systemically healthy individuals, can concentration of specific metabolites in the GCF be used to discriminate subjects with healthy periodontium (H) or gingivitis from patients with periodontitis (P) and which is the diagnostic accuracy?" Quality of included studies was rated using a modified version of the QUADOMICS tool. Meta-analysis was conducted whenever possible. After the screening of 1,554 titles, 15 studies were selected, with sample size ranging from 30 to 93 subjects. Eleven studies performed targeted metabolomics analysis and provided data for 10 metabolites. Among the most consistent markers, malondialdehyde levels were found higher in the P group compared with H group (SMD = 2.86; 95% CI: 1.64, 4.08). Also, a significant increase of 8-hydroxy-deoxyguanosine, 4-hydroxynonenal, and neopterin was detected in periodontally diseased sites, while glutathione showed an inverse trend. When considering data from untargeted metabolomic analysis in four studies, more than 40 metabolites were found significantly discriminant, mainly related to amino acids and lipids degradation pathways. Notably, only one study reported measures of diagnostic accuracy. Several metabolites were differentially expressed in GCF of subjects across different periodontal conditions, having a major potential for investigating periodontal pathophysiology and for site-specific diagnosis. Oxidative stress-related molecules, such as malondialdehyde and 8-hydroxy-deoxyguanosine, were the most consistently associated to periodontitis (PROSPERO CRD42020188482).

Shared microbiological and immunological patterns in periodontitis and IBD: A scoping review

OBJECTIVES

To extract the microbiological and immunological evidence underpinning the association between periodontitis and inflammatory bowel disease (IBD).

METHODS

Relevant articles were sorted through a systematic search on PubMed, Embase, Scopus and Web of Science up to October 2020. Available evidence was grouped in three different clusters: (a) studies that examined oral microbial alterations in IBD patients; (b) studies that investigated intestinal dysbiosis in patients with periodontitis; and (c) evidence for a shared immunological pattern between the two conditions.

RESULTS

A total of 15 studies involving 1,171 patients were included. Oral microbiome, either subgingival or salivary, was consistently altered in patients with IBD compared to healthy subjects (a) Additionally, gut dysbiotic microbiota of IBD patients was colonized by pathobionts from oral origin, either via haematogenous or enteric route. Suffering from periodontitis is associated with lower alpha diversity in the gut microbiome (b) Lastly, both IBD and periodontitis are characterized by similar expression patterns of inflammatory cytokines at the gingival and gut levels that are exacerbated when both diseases are present (c).

CONCLUSIONS

Periodontitis and IBD share common dysbiotic and immunological traits. Well-designed preclinical models and longitudinal cohort studies are required to better explore the causal pathways between the two conditions (PROSPERO CRD42020194379).

Salivary metabolomics for the diagnosis of periodontal diseases: a systematic review with methodological quality assessment

INTRODUCTION

Early diagnosis of periodontitis by means of a rapid, accurate and non-invasive method is highly desirable to reduce the individual and epidemiological burden of this largely prevalent disease.

OBJECTIVES

The aims of the present systematic review were to examine potential salivary metabolic biomarkers and pathways associated to periodontitis, and to assess the accuracy of salivary untargeted metabolomics for the diagnosis of periodontal diseases.

METHODS

Relevant studies identified from MEDLINE (PubMed), Embase and Scopus databases were systematically examined for analytical protocols, metabolic biomarkers and results from the multivariate analysis (MVA). Pathway analysis was performed using the MetaboAnalyst online software and quality assessment by means of a modified version of the QUADOMICS tool.

RESULTS

Twelve studies met the inclusion criteria, with sample sizes ranging from 19 to 130 subjects. Compared to periodontally healthy individuals, valine, phenylalanine, isoleucine, tyrosine and butyrate were found upregulated in periodontitis patients in most studies; while lactate, pyruvate and N-acetyl groups were the most significantly expressed in healthy individuals. Metabolic pathways that resulted dysregulated are mainly implicated in inflammation, oxidative stress, immune activation and bacterial energetic metabolism. The findings from MVA revealed that periodontitis is characterized by a specific metabolic signature in saliva, with coefficients of determination ranging from 0.52 to 0.99.

CONCLUSIONS

This systematic review summarizes candidate metabolic biomarkers and pathways related to periodontitis, which may provide opportunities for the validation of diagnostic or predictive models and the discovery of novel targets for monitoring and treating such a disease (PROSPERO CRD42020188482).

Periodontitis, Edentulism, and Risk of Mortality: A Systematic Review with Meta-analyses

Periodontitis has been independently associated with the chronic noncommunicable diseases that most frequently lead to death worldwide. The aim of the present systematic review was to study whether people with periodontitis/edentulism are at increased risk of all-cause and cause-specific mortality as compared with those without periodontitis/edentulism. Cohort studies were included that 1) evaluated periodontitis or edentulism as exposures in relation to all-cause or cause-specific mortality as an outcome and 2) reported effect estimates as hazard ratios, risk ratios, or odds ratios with 95% CIs or crude numbers. Two review authors independently searched for eligible studies, screened the titles and abstracts, did full-text analysis, extracted the data from the published reports, and performed the risk-of-bias assessment. In case of disagreement, a third review author was consulted. Study results were summarized through random effects meta-analyses. A total of 57 studies were included, involving 48 cohorts and 5.71 million participants. Periodontitis was associated with increased risk of all-cause mortality (risk ratio, 1.46 [95% CI, 1.15 to 1.85]) and mortality due to cardiovascular diseases (1.47 [1.14 to 1.90]), cancer (1.38 [1.24 to 1.53]), coronary heart disease (2.58 [2.20 to 3.03]), cerebrovascular diseases (3.11 [2.42 to 3.98]), but not pneumonia (0.98 [0.69 to 1.38]). Edentulism (all types) was associated with increased risk of all-cause mortality (1.66 [1.46 to 1.88]) and mortality due to cardiovascular diseases (2.03 [1.50 to 2.74]), cancer (1.55 [1.24 to 1.94]), pneumonia (1.72 [1.07 to 2.78]), coronary heart disease (2.98 [2.43 to 3.65]), and cerebrovascular diseases (3.18 [2.24 to 4.51]). Periodontitis and its ultimate sequela (edentulism) are associated with an increased risk of all-cause and cause-specific mortality (PROSPERO CRD42018100095).

Effect of non-surgical periodontal therapy on salivary metabolic fingerprint of generalized chronic periodontitis using nuclear magnetic resonance spectroscopy

OBJECTIVE

Metabolomic analysis of saliva proved its accuracy in discriminating patients with generalized chronic periodontitis (GCP) from healthy subjects by identifying specific molecular signatures of the disease. There is lack of investigations concerning the effect of periodontal treatment on individual metabolic fingerprints. Therefore, the aim of this study was to determine whether non-surgical periodontal therapy could change salivary metabolomic profile in GCP to one more similar to periodontal health.

DESIGN

Unstimulated whole saliva of 32 controls and 19 GCP patients were obtained prior to and 3 months after conventional staged non-surgical periodontal therapy. Metabolic profiling was performed using Nuclear Magnetic Resonance (NMR) spectroscopy, followed by univariate and multivariate paired approaches to assess the changes introduced by the therapy.

RESULTS

In GCP group, periodontal treatment led to an improvement in all clinical parameters (p < 0.001). The accuracy of the multivariate model in discriminating the metabolomic profile of each GCP patient at two time points was 92.5%. Despite the almost perfect separation of the spectra in the metabolic space, the univariate analysis failed to identify significant variations in single metabolite content. The post-treatment metabolic profile of GCP patients could not be assimilated to that of healthy controls who exhibited different levels of lactate, pyruvate, valine, proline, tyrosine, and formate.

CONCLUSIONS

Based on these data, NMR-spectroscopic analysis revealed that, despite significant changes in the overall metabolomic fingerprint after non-surgical therapy, GCP patients maintained a distinctive metabolic profile compared to healthy individuals.

Analysis of salivary phenotypes of generalized aggressive and chronic periodontitis through nuclear magnetic resonance-based metabolomics

BACKGROUND

Recent findings about the differential gene expression signature of periodontal lesions have raised the hypothesis of distinctive biological phenotypes expressed by generalized chronic periodontitis (GCP) and generalized aggressive periodontitis (GAgP) patients. Therefore, this cross-sectional investigation was planned, primarily, to determine the ability of nuclear magnetic resonance (NMR) spectroscopic analysis of unstimulated whole saliva to discriminate GCP and GAgP disease-specific metabolomic fingerprint and, secondarily, to assess potential metabolites discriminating periodontitis patients from periodontally healthy individuals (HI).

METHODS

NMR-metabolomics spectra were acquired from salivary samples of patients with a clinical diagnosis of GCP (n = 33) or GAgP (n = 28) and from HI (n = 39). The clustering of HI, GCP, and GAgP patients was achieved by using a combination of the Principal Component Analysis and Canonical Correlation Analysis on the NMR profiles.

RESULTS

These analyses revealed a significant predictive accuracy discriminating HI from GCP, and discriminating HI from GAgP patients (both 81%). In contrast, the GAgP and GCP saliva samples seem to belong to the same metabolic space (60% predictive accuracy). Significantly lower levels (P < 0.05) of pyruvate, N-acetyl groups and lactate and higher levels (P < 0.05) of proline, phenylalanine, and tyrosine were found in GCP and GAgP patients compared with HI.

CONCLUSIONS

Within the limitations of this study, CGP and GAgP metabolomic profiles were not unequivocally discriminated through a NMR-based spectroscopic analysis of saliva.