Systemic effects of periodontitis treatment in patients with type 2 diabetes: a 12 month, single-centre, investigator-masked, randomised trial

Periodontitis and implant complications in diabetes

Epidemiologic evidence indicates that periodontitis is more frequent in patients with uncontrolled diabetes mellitus than in healthy controls, suggesting that it could be considered the "sixth complication" of diabetes. Actually, diabetes mellitus and periodontitis are two extraordinarily prevalent chronic diseases that share a number of comorbidities all converging toward an increased risk of cardiovascular disease. Periodontal treatment has recently been shown to have the potential to improve the metabolic control of diabetes, although long-term studies are lacking. Uncontrolled diabetes also seems to affect the response to periodontal treatment, as well as the risk to develop peri-implant diseases. Mechanisms of associations between diabetes mellitus and periodontal disease include the release of advanced glycation end products as a result of hyperglycemia and a range of shared predisposing factors of genetic, microbial, and lifestyle nature. This review discusses the evidence for the risk of periodontal and peri-implant disease in diabetic patients and the potential role of the dental professional in the diabetes-periodontal interface.

Multiprotein Inhibitory Effect of Dietary Polyphenol Rutin from Whole Green Jackfruit Flour Targeting Different Stages of Diabetes Mellitus: Defining a Bio-Computational Stratagem

The anti-diabetic potential of whole unripe jackfruit (peel with pulp, flake, and seed) was investigated using inhibitory assays for α-glucosidase, α-amylase, aldose reductase, and glycation at multiple stages. Using activity-guided repeated fractionation on a silica gel column chromatography, dietary flavonoid rutin with potent antihyperglycemic activity was extracted from the methanol extract of whole jackfruit flour (MJ). Rutin was found to inhibit both α-glucosidase (IC50: 7.86 µg/mL) and α-amylase (IC50: 22.00 µg/mL) in a competitive manner of inhibition with low Ki values. In addition, in vitro glycation experiments revealed that rutin prevented each stage of protein glycation as well as the production of intermediate molecules. Furthermore, rutin significantly inhibited aldose reductase (IC50: 2.75 µg/mL) in a non-competitive manner. During in silico studies, molecular docking and molecular dynamics simulation studies have suggested that rutin has a high binding affinity for the enzymes studied, which could explain its inhibitory effects. Rutin interacted with the key residues of the target enzymes’ inhibitor binding sites. Compared to the controls used, rutin had a higher binding efficiency as well as stability in the inhibitor binding pocket of the target enzymes. According to our findings, the presence of rutin is more likely to be associated with the potential of MJ in antihyperglycemic activity via inhibition of α-glucosidase and in anti-diabetic action via inhibition of the polyol pathway and protein glycation. The bio-computational study indicates rutin as a potential lead inhibitor of all the target enzymes used and could be used as an effective anti-diabetic drug in the near future.

Psychologically informed oral health interventions in pregnancy and type 2 diabetes: a scoping review protocol

INTRODUCTION

Periodontal health is becoming a recognised component in managing gestational diabetes. Gestational diabetes is characterised as raised blood glucose levels first discovered in pregnancy and managed similarly to type 2 diabetes. Currently, the standard intervention for gestational diabetes in the UK entails dietary modifications and physical activity interventions. However, considering the literature discussed in this review, it is argued that oral health advice and support should also become an integrated part of gestational diabetes management.

OBJECTIVE

The objective of this scoping review is to map out psychologically informed oral health interventions in pregnancy and type 2 diabetes. This will inform the development of a new behavioural intervention to promote oral health-related behaviours in women with gestational diabetes. As no literature exists on oral health interventions in gestational diabetes, it was deemed appropriate to synthesise the evidence on oral health interventions designed for pregnant women and individuals with type 2 diabetes.

METHODOLOGY

The scoping review will be conducted using the Joanna Briggs Institute's methodology for scoping reviews. Studies including pregnant women and individuals with type 2 diabetes over 18 years of age will be included. Only studies including a psychologically informed oral health intervention will be considered. The authors will consider experimental and quasi-experimental research designs. The Ovid Interface including EMBASE, Medline, Global Health, APA PsychInfo, Health Management Information, Maternity, Infant Care Database and the Cochrane Library will be used as information sources. The planned searches will commence on the week of the 25 July 2022. Only articles in Danish and English will be considered. The study selection will follow the Preferred Reporting Items for Scoping Reviews process. The data will be presented using narrative synthesis.

ETHICS AND DISSEMINATION

No ethical approval is needed for this review. The results will be published in a relevant scientific journal.

Effects of One-Stage Full-Mouth Scaling and Root Planing with Azithromycin on Diabetes and Periodontal Disease: A Randomized Controlled Trial

Recent reports show that hemoglobin A1c (HbA1c) can be lowered by improving chronic inflammation in periodontal patients with diabetes mellitus and that full-mouth scaling and root planing (FM-SRP), in combination with azithromycin (AZM) treatment, can reduce early periodontal inflammation. However, the association of FM-SRP and AZM with periodontitis and HbA1c in patients with diabetes is largely unknown. This study investigated periodontitis and HbA1c in patients with diabetes after receiving FM-SRP and AZM to evaluate which clinical parameters most reflect the diabetic condition. Fifty-one periodontal patients with diabetes mellitus were included in this study. In total, 25 patients were assigned to the FM-SRP group in which patients were treated with FM-SRP in combination with AZM, and 26 patients were assigned to the control group in which only supragingival calculus removal was performed along with the provision of oral hygiene instructions. We evaluated periodontal parameters (probing pocket depth, periodontal inflamed surface area (PISA), bleeding on probing), and periodontal bacteria and biochemical parameters (HbA1c, high-sensitive C-reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1)) at baseline (BL) and 1, 3, 6, and 9 months after treatment. Compared with BL values, the FM-SRP group showed improved clinical parameters, reduced periodontal pathogens, and significantly lower HbA1c. Inflammatory cytokines (hs-CRP, TNF-α, IL-6) were significantly reduced one month after treatment and remained low thereafter. MCP-1 did not change significantly during the experimental period. PISA showed a strong correlation with HbA1c, hs-CRP, and TNF-α. FM-SRP, in combination with AZM, produced clinical, microbiological, and HbA1c improvements in periodontal patients with previously diagnosed diabetes mellitus. Additionally, PISA was shown to be a useful index for assessing the diabetic status of patients with periodontal disease.

Oral Lesions Associated with COVID-19 and the Participation of the Buccal Cavity as a Key Player for Establishment of Immunity against SARS-CoV-2

BACKGROUND

Some oral lesions have been described in patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); the possibility has been raised that the buccal lesions observed in patients with the coronavirus disease 2019 (COVID-19) are due to this virus and the patient's systemic condition. The aim of this review was to integrate the knowledge related to the oral lesions associated with COVID-19 and the participation of the buccal cavity in the establishment of immunity against SARS-CoV-2.

METHODS

A literature search on the manifestations of buccal lesions from the beginning of the pandemic until October 2021 was carried out by using the PubMed database. A total of 157 scientific articles were selected from the library, which included case reports and reports of lesions appearing in patients with COVID-19.

RESULTS

Oral lesions included erosions, ulcers, vesicles, pustules, plaques, depapillated tongue, and pigmentations, among others. The oral cavity is a conducive environment for the interaction of SARS-CoV-2 with the mucosal immune system and target cells; direct effects of the virus in this cavity worsen the antiviral inflammatory response of underlying oral disorders, immunodeficiencies, and autoimmunity primarily.

CONCLUSIONS

The oral cavity is an accessible and privileged environment for the interaction of SARS-CoV-2 with the mucosal immune system and target cells; the direct effects of the virus in this cavity worsen the antiviral inflammatory response of underlying oral disorders, in particular those related to immunodeficiencies and autoimmunity.

Compare the physicochemical and biological properties of engineered polymer-functionalized silver nanoparticles against Porphyromonas gingivalis

Background

Some polymer-functionalized AgNPs (P-AgNPs) have been developed to optimize the biological properties of AgNPs. However, there are no studies in the literature comparing the differences in physicochemical and biological properties of AgNPs caused by various polymer-functionalizations and providing evidence for the selection of polymers to optimize AgNPs.

Methods

Two AgNPs with similar nano-size and opposite surface charges were synthesized and functionalized by seven polymers. Their physicochemical properties were evaluated by UV-Visible absorption, dynamic light scattering, transmission electron microscopy and inductively coupled plasma optical emission spectroscopy. Their biological properties against Porphyromonas gingivalis and human gingival fibroblast were investigated by MIC determination, time-dependent antibacterial assay, antibiofilm activity and cell viability assay. Silver diamine fluoride, AgNO3 and metronidazole were used as positive controls.

Results

Comparative analysis found that there were no significant differences between P-AgNPs and AgNPs in nano-size and in surface charge. Raman spectroscopy analysis provided evidence about the attachment of polymers on AgNPs. For antibacterial property, among the negatively charged AgNPs, only polyvinylpyrrolidone (PVP)-functionalized AgNPs-1 showed a significant lower MIC value than AgNPs-1 (0.79 vs. 4.72 μg/ml). Among the positively charged AgNPs, the MIC values of all P-AgNPs (0.34–4.37 μg/ml) were lower than that of AgNPs-2 (13.89 μg/ml), especially PVP- and Pluronic127-AgNPs-2 (1.75 and 0.34 μg/ml). For antibiofilm property, PVP-AgNPs-1 (7.86 μg/ml, P = 0.002) and all P-AgNPs-2 (3.42–31.14 μg/ml, P < 0.001) showed great antibiofilm effect against P. gingivalis biofilm at 5* to 10*MIC level. For cytotoxicity, all negatively charged AgNPs and PVP-AgNPs-2 showed no cytotoxicity at MIC level, but significant cytotoxicity was detected at 2.5* to 10*MIC levels.

Conclusion

Among the polymers studied, polymer functionalization does not significantly alter the physical properties of AgNPs, but modifies their surface chemical property. These modifications, especially the functionalization of PVP, contribute to optimize the antibacterial and antibiofilm properties of AgNPs, while not causing cytotoxicity at the MIC level.

Host Response Modulation Therapy in the Diabetes Mellitus—Periodontitis Conjuncture: A Narrative Review

The inflammatory response of the host in periodontitis is the phenomenon that underlies the onset and evolution of periodontal destructive phenomena. A number of systemic factors, such as diabetes mellitus (DM), can negatively affect the patient with periodontitis, just as the periodontal disease can aggravate the status of the DM patient. Host response modulation therapy involves the use of anti-inflammatory and anti-oxidant products aimed at resolving inflammation, stopping destructive processes, and promoting periodontal healing, all important aspects in patients with high tissue loss rates, such as diabetic patients. This paper reviews the data available in the literature on the relationship between DM and periodontitis, the main substances modulating the inflammatory response (nonsteroidal anti-inflammatory drugs, sub-antimicrobial doses of doxycycline, or omega-3 fatty acids and their products, specialized pro-resolving mediators), as well as their application in diabetic patients.

Oral health associated with incident diabetes but not other chronic diseases: A register-based cohort study

Introduction

Oral infectious diseases are common chronic oral diseases characterized by a chronic inflammatory condition. We investigated chronic oral diseases as potential risk factors for systemic chronic diseases, diabetes mellitus, connective tissue diseases, seropositive rheumatoid arthritis, ulcerative colitis, and Crohn's disease, as well as severe psychotic and other severe mental disorders.

Methods

The cohort comprised 68,273 patients aged ≥ 29 years with at least one dental visit to the Helsinki City Health Services between 2001 and 2002. The cohort was linked to the data on death (Statistics Finland), cancer (Finnish Cancer Registry), and drug reimbursement (Finnish Social Insurance Institution) and followed until death or the end of 2013. The outcomes of interest were the incidences of chronic diseases measured starting with special refund medication, which means Social Insurance Institution partly or fully reimburses medication costs. Outcomes of interest were diabetes mellitus, connective tissue diseases, seropositive rheumatoid arthritis, ulcerative colitis and Crohn's disease, and severe mental disorders.

Results

The mean follow-up time was 9.8 years. About 25% of the study population had periodontitis, 17% caries, over 70% apical periodontitis, and 9% <24 teeth at the start of follow-up. Diabetes was the only chronic systemic condition associated with oral health variables. Having 24 to 27 teeth was associated with a higher incidence rate ratio (IRR) (1.21, 95% confidence interval 1.09-1.33) compared to having 28 or more teeth; the IRR for having 23 or less was 1.40 (1.22-1.60). Having periodontitis (1.10, 1.01-1.20), caries (1.12, 1.01-1.23), or apical periodontitis (1.16, 1.04-1.30) is also associated with a higher risk of diabetes.

Conclusion

Our epidemiological 10 years follow-up study suggests that the association exists between chronic oral diseases and diabetes, warranting close collaboration among patient's healthcare professionals.

Encounters and management of oral conditions at general medical practices in Australia

Background

Poor oral health has been widely recognised as an ongoing public health issue. Patients with oral conditions may visit either a general practitioner (GP) or a dental practitioner for management. The aims of this study are to report (i) the GP management rate of oral health conditions by patient and GP demographics, (ii) what specific oral conditions were managed, and (iii) how GPs managed oral conditions.

Methods

Data from the Bettering the Evaluation and Care of Health study (2006 to 2016 inclusive) were analysed. Descriptive statistics with 95% confidence intervals around point estimates were used to summarise data. Multivariate logistic regression was performed to determine the independent effect of patient and GP characteristics.

Results

A total of 972,100 GP encounters were included in the dataset, with oral condition-related encounters managed at a rate of 1.19 oral conditions per 100 GP encounters. Patients who were aged 54 years or younger, resided in a socioeconomically disadvantaged area, came from a non-English speaking background or Indigenous background were more likely to have oral conditions managed by GPs. The most commonly reported oral conditions were dental and oral mucosa-related. Over 60% of oral conditions were managed by GPs through prescribed medications.

Conclusions

This study provided an overview of management of oral conditions by GPs in Australia. Patients from certain vulnerable demographic groups were more likely to attend a GP for management of oral conditions. Common oral conditions and management approaches were identified. The findings of this study contribute to public health and health policy discussions around optimising primary care provision in oral health.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-08299-2.

The Roles of Neutrophils Linking Periodontitis and Atherosclerotic Cardiovascular Diseases

Inflammation plays a crucial role in the onset and development of atherosclerosis. Periodontitis is a common chronic disease linked to other chronic inflammatory diseases such as atherosclerotic cardiovascular disease (ASCVD). The mechanistic pathways underlying this association are yet to be fully understood. This critical review aims at discuss the role of neutrophils in mediating the relationship between periodontitis and ASCVD. Systemic inflammation triggered by periodontitis could lead to adaptations in hematopoietic stem and progenitor cells (HSPCs) resulting in trained granulopoiesis in the bone marrow, thereby increasing the production of neutrophils and driving the hyper-responsiveness of these abundant innate-immune cells. These alterations may contribute to the onset, progression, and complications of atherosclerosis. Despite the emerging evidence suggesting that the treatment of periodontitis improves surrogate markers of cardiovascular disease, the resolution of periodontitis may not necessarily reverse neutrophil hyper-responsiveness since the hyper-inflammatory re-programming of granulopoiesis can persist long after the inflammatory inducers are removed. Novel and targeted approaches to manipulate neutrophil numbers and functions are warranted within the context of the treatment of periodontitis and also to mitigate its potential impact on ASCVD.

Evaluation of an Oral Care Program to Improve the Oral Health of Home-Dwelling Older People

The aim of this study was to evaluate the impact of the implementation of an Oral Care Program on home care nurses’ attitudes and knowledge about oral health (care) and the impact on older people’s oral health. A pre–post study, without a control group, was conducted. A preventive Oral Care Program (OCP) was designed, focusing on home care nurses and older people, in collaboration with dental hygienists. Implementation was measured with questionnaires at baseline and after 6 months for home care nurses; for older people, implementation was measured at baseline and after 3 months with the Oral Health Assessment Tool and a questionnaire about oral (self) care between January 2018 and September 2019. Although the study design has limitations, the oral health of older people improved significantly after 3 months and the OCP was most beneficial for people with full dentures. The OCP improved knowledge and attitude of home care nurses. The program fitted well with the daily work routines of home care nurses. Individual-centered care plans for older people, education of home care nurses and the expertise of the dental hygienists have added value in home care nursing. Future implementations should focus on older people with natural teeth.

Single-Cell Transcriptomic Atlas of Gingival Mucosa in Type 2 Diabetes

The oral gingival barrier is a constantly stimulated and dynamic environment where homeostasis is often disrupted, resulting in inflammatory periodontal diseases. Type 2 diabetes (T2D) has been reported to be associated with gingival barrier dysfunction, but the effect and underlying mechanism are inconclusive. Herein, we performed single-cell RNA sequencing (scRNA-seq) of gingiva from leptin receptor-deficient mice (db/db) to examine the gingival heterogeneity in the context of T2D. Periodontal health of control mice is characterized by populations of Krt14⁺-expressing epithelial cells and Col1a1⁺-fibroblasts mediating immune homeostasis primarily through the enrichment of innate lymphoid cells. The db/db gingiva exhibited decreased epithelial/stromal ratio and dysfunctional barrier. We further observed stromal, particularly fibroblast immune hyperresponsiveness, linked to the recruitment of myeloid-derived cells at the db/db gingiva. Both scRNA-seq and histological analysis suggested the inflammatory signaling between fibroblasts and neutrophils as a potential driver of diabetes-induced periodontal damage. Notably, the "immune-like" stromal cells were wired toward the induction of gingival γδ T hyperresponsiveness in db/db mice. Our work reveals that the "immune-like" fibroblasts with transcriptional diversity are involved in the innate immune homeostasis at the diabetic gingiva. It highlights a potentially significant role of these cell types in its pathogenesis.

Cardiovascular Diseases and Periodontitis

Periodontitis is a chronic inflammatory disease of the tooth-supporting connective tissue and alveolar bone that is initiated by a bacterial biofilm in periodontal pockets. It affects about half of adults in the Western world, and is associated with a range of systemic comorbidities, e.g., cardiovascular disease (CVD), diabetes and rheumatoid arthritis, and these diseases share overlapping systemic and target tissue inflammatory mechanisms. Indeed, mounting evidence has indicated that their association is causal and built on the presence of systemic low-grade inflammation (LGI). Prior research linking periodontitis to CVD has mainly been derived from experimental studies, observational data, and small interventional trials with surrogate markers of CVD, e.g., endothelial dysfunction. However, recent data from randomised studies have demonstrated that intensive treatment of periodontitis can reduce blood pressure in patients with hypertension in conjunction with reduction of systemic inflammatory markers. Furthermore, targeted anti-inflammatory therapy has been shown to reduce recurrent events in patients with established CVD and LGI. Along this line, the concept of residual inflammatory risk has emerged as an independent new risk factor for atherothrombotic CVD. The present review summarizes translational evidence indicating that periodontitis is a risk factor for CVD dependent on LGI, and we conclude that treatment of periodontitis is likely to contribute importantly to reduction of residual inflammatory risk.

Maladaptive innate immune training of myelopoiesis links inflammatory comorbidities

Bone marrow (BM)-mediated trained innate immunity (TII) is a state of heightened immune responsiveness of hematopoietic stem and progenitor cells (HSPC) and their myeloid progeny. We show here that maladaptive BM-mediated TII underlies inflammatory comorbidities, as exemplified by the periodontitis-arthritis axis. Experimental-periodontitis-related systemic inflammation in mice induced epigenetic rewiring of HSPC and led to sustained enhancement of production of myeloid cells with increased inflammatory preparedness. The periodontitis-induced trained phenotype was transmissible by BM transplantation to naive recipients, which exhibited increased inflammatory responsiveness and disease severity when subjected to inflammatory arthritis. IL-1 signaling in HSPC was essential for their maladaptive training by periodontitis. Therefore, maladaptive innate immune training of myelopoiesis underlies inflammatory comorbidities and may be pharmacologically targeted to treat them via a holistic approach.

Are Inflamed Periodontal Tissues Endogenous Source of Advanced Glycation End-Products (AGEs) in Individuals with and without Diabetes Mellitus? A Systematic Review

Advanced glycation end-products (AGEs) are heterogeneous compounds formed when excess sugars condense with the amino groups of nucleic acids and proteins. Increased AGEs are associated with insulin resistance and poor glycemic control. Recently, inflamed periodontal tissues and certain oral bacteria were observed to increase the local and systemic AGE levels in both normoglycemic and hyperglycemic individuals. Although hyperglycemia induced AGE and its effect on the periodontal tissues is known, periodontitis as an endogenous source of AGE formation is not well explored. Hence, this systematic review is aimed to explore, for the first time, whether inflamed periodontal tissues and periodontal pathogens have the capacity to modulate AGE levels in individuals with or without T2DM and how this affects the glycemic load. Six electronic databases were searched using the following keywords: (Periodontitis OR Periodontal disease OR Periodontal Inflammation) AND (Diabetes mellitus OR Hyperglycemia OR Insulin resistance) AND Advanced glycation end products. The results yielded 1140 articles, of which 13 articles were included for the review. The results showed that the mean AGE levels in gingival crevicular fluid was higher in individuals with diabetes mellitus and periodontitis (521.9 pg/mL) compared to healthy individuals with periodontitis (234.84 pg/mL). The serum AGE levels in normoglycemic subjects having periodontitis was higher compared to those without periodontitis (15.91 ng/mL vs. 6.60 ng/mL). Tannerella forsythia, a common gram-negative anaerobe periodontal pathogen in the oral biofilm, was observed to produce methylglyoxal (precursor of AGE) in the gingival tissues. Increased AGE deposition and activate of AGE receptors was noted in the presence of periodontitis in both normoglycemic and hyperglycemic individuals. Hence, it can be concluded that periodontitis can modulate the local and systemic levels of AGE levels even in absence of hyperglycemia. This explains the bidirectional relationship between periodontitis and development of prediabetes, incident diabetes, poor glycemic control, and insulin resistance.

Periodontitis exacerbates endothelial dysfunctions partly via endothelial-mesenchymal transition in streptozotocin-induced diabetes rats

OBJECTIVES

Periodontal infections are related to the expansion of diabetes cardiovascular problems. However, the pathological process and probable mechanism remain unexplained. This study investigated the impact of periodontitis on streptozotocin (STZ)-induced diabetes rats' carotid artery.

METHODS

We randomized 24 Sprague-Dawley (SD) rats into four groups: control, chronic periodontitis (CP), diabetes mellitus (DM), and DM +CP groups. Fasting blood glucose (FBG) and hemoglobin A_1c (HBA_1c ) were measured to verify the establishment of the DM model. After euthanasia, the maxillary was collected for further studies like hematoxylin-eosin (HE), Masson staining, and micro-computed tomography (micro-CT) analysis. Immunofluorescence (IF) staining was used to detect endothelial-mesenchymal transition (EndMT)-related markers in carotid artery wall. We further used ELISA and quantitative real-time PCR to investigate the effect of high glucose (HG) and Porphyromonas gingivalis lipopolysaccharide (P.g-LPS) on human umbilical vein endothelial cells (HUVECs).

RESULTS

Compared with DM and CP groups, bone resorption and pathological changes of the vascular wall were the most serious in the DM+CP group. The vascular wall of the DM+CP group had a higher level of interleukin (IL)-6 and vascular cell adhesion molecule 1 (VCAM-1). The carotid artery vascular wall of the DM+CP group contained more cells that expressed both mesenchymal and endothelial cell markers, along with elevated transcription factor levels. Furthermore, P.g-LPS and HG upregulated the inflammatory cytokines expression and caused phenotypic changes of HUVECs in vitro.

CONCLUSION

Periodontitis exacerbates endothelial dysfunctions partly via endothelial-mesenchymal transition in STZ-induced diabetes rats.

Treatment of periodontitis for glycaemic control in people with diabetes mellitus

BACKGROUND

Glycaemic control is a key component in diabetes mellitus (diabetes) management. Periodontitis is the inflammation and destruction of the underlying supporting tissues of the teeth. Some studies have suggested a bidirectional relationship between glycaemic control and periodontitis.  Treatment for periodontitis involves subgingival instrumentation, which is the professional removal of plaque, calculus, and debris from below the gumline using hand or ultrasonic instruments. This is known variously as scaling and root planing, mechanical debridement, or non-surgical periodontal treatment. Subgingival instrumentation is sometimes accompanied by local or systemic antimicrobials, and occasionally by surgical intervention to cut away gum tissue when periodontitis is severe. This review is part one of an update of a review published in 2010 and first updated in 2015, and evaluates periodontal treatment versus no intervention or usual care.  OBJECTIVES: To investigate the effects of periodontal treatment on glycaemic control in people with diabetes mellitus and periodontitis.

SEARCH METHODS

An information specialist searched six bibliographic databases up to 7 September 2021 and additional search methods were used to identify published, unpublished, and ongoing studies.  SELECTION CRITERIA: We searched for randomised controlled trials (RCTs) of people with type 1 or type 2 diabetes mellitus and a diagnosis of periodontitis that compared subgingival instrumentation (sometimes with surgical treatment or adjunctive antimicrobial therapy or both) to no active intervention or 'usual care' (oral hygiene instruction, education or support interventions, and/or supragingival scaling (also known as PMPR, professional mechanical plaque removal)). To be included, the RCTs had to have lasted at least 3 months and have measured HbA1c (glycated haemoglobin).

DATA COLLECTION AND ANALYSIS

At least two review authors independently examined the titles and abstracts retrieved by the search, selected the included trials, extracted data from included trials, and assessed included trials for risk of bias. Where necessary and possible, we attempted to contact study authors. Our primary outcome was blood glucose levels measured as glycated (glycosylated) haemoglobin assay (HbA1c), which can be reported as a percentage of total haemoglobin or as millimoles per mole (mmol/mol). Our secondary outcomes included adverse effects, periodontal indices (bleeding on probing, clinical attachment level, gingival index, plaque index, and probing pocket depth), quality of life, cost implications, and diabetic complications.

MAIN RESULTS

We included 35 studies, which randomised 3249 participants to periodontal treatment or control. All studies used a parallel-RCT design and followed up participants for between 3 and 12 months. The studies focused on people with type 2 diabetes, other than one study that included participants with type 1 or type 2 diabetes. Most studies were mixed in terms of whether metabolic control of participants at baseline was good, fair, or poor. Most studies were carried out in secondary care.  We assessed two studies as being at low risk of bias, 14 studies at high risk of bias, and the risk of bias in 19 studies was unclear. We undertook a sensitivity analysis for our primary outcome based on studies at low risk of bias and this supported the main findings. Moderate-certainty evidence from 30 studies (2443 analysed participants) showed an absolute reduction in HbA1c of 0.43% (4.7 mmol/mol) 3 to 4 months after treatment of periodontitis (95% confidence interval (CI) -0.59% to -0.28%; -6.4 mmol/mol to -3.0 mmol/mol). Similarly, after 6 months, we found an absolute reduction in HbA1c of 0.30% (3.3 mmol/mol) (95% CI -0.52% to -0.08%; -5.7 mmol/mol to -0.9 mmol/mol; 12 studies, 1457 participants), and after 12 months, an absolute reduction of 0.50% (5.4 mmol/mol) (95% CI -0.55% to -0.45%; -6.0 mmol/mol to -4.9 mmol/mol; 1 study, 264 participants). Studies that measured adverse effects generally reported that no or only mild harms occurred, and any serious adverse events were similar in intervention and control arms. However, adverse effects of periodontal treatments were not evaluated in most studies.

AUTHORS' CONCLUSIONS

Our 2022 update of this review has doubled the number of included studies and participants, which has led to a change in our conclusions about the primary outcome of glycaemic control and in our level of certainty in this conclusion. We now have moderate-certainty evidence that periodontal treatment using subgingival instrumentation improves glycaemic control in people with both periodontitis and diabetes by a clinically significant amount when compared to no treatment or usual care. Further trials evaluating periodontal treatment versus no treatment/usual care are unlikely to change the overall conclusion reached in this review.

Efficacy of Antioxidant Supplementation to Non-Surgical Periodontal Therapy on Metabolic Control in Type 2 Diabetes Patients: A Network Meta-Analysis

This network meta-analysis (NMA) investigated the effectiveness of antioxidants as adjuncts to non-surgical periodontal therapy (NSPT) in the glycated hemoglobin (HbA1c) control of type 2 diabetes (T2D) patients with periodontitis. PubMed, Cochrane, LILACS, Web of Science, Scopus, Embase, LIVIVO, and grey literature were searched. Risk of bias was assessed with the RoB v2.0 tool. A frequentist NMA assessed HbA1c improvement, through standardized mean difference under a random-effects model. Certainty of evidence was addressed through the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) partially contextualized framework. Ten randomized controlled clinical trials were included, with 234 patients receiving alpha lipoic acid (ALA), cranberry juice, cranberry juice enriched with omega-3, fenugreek, ginger, grape seed, lycopene, melatonin, omega-3, propolis or vitamin C supplementation to NSPT, and 220 patients receiving NSPT alone or with placebo. Nine studies were meta-analyzed. HbA1c improved when NSPT was combined with propolis, ALA and melatonin supplementation (moderate-to-low certainty), compared to NSPT alone or with placebo. Risk of bias issues were found in eight studies. In conclusion, the use of propolis supplementation to NSPT probably results in HbA1c improvement in T2D patients with periodontitis (large effect with moderate certainty), while ALA and melatonin supplementation may contribute to reduce the HbA1c in T2D patients with periodontitis (large effects with low certainty).

Acute Myocardial Infarction and Periodontitis: Importance of Awareness and Prevention in Latin America

By 2030, non-communicable diseases will have accounted for more than three-quarters of deaths worldwide. Cardiovascular diseases (CVDs) have been the leading cause of death worldwide for several years. Acute myocardial infarction (AMI) is a CVD characterized by necrosis of the heart at the myocardial level due to prolonged ischemia caused by the reduction or sudden absence of coronary blood supply. The prevalence of AMI is higher in men at all ages. The incidence of AMI has decreased in industrialized nations; however, it has been on the rise in Latin America (LATAM) due to lifestyle changes. These changes have caused the combined incidence of CVDs and unresolved health concerns in LATAM, such as infections and malnutrition. It is well known that periodontitis, a highly prevalent chronic infectious inflammatory disease, has been associated with systemic diseases, such as diabetes, kidney diseases, and AMI. This review addresses proposed aspects of the correlation between periodontitis and AMI, explains the importance of preventing periodontitis and CVDs, and analyzes the preventative measures being implemented in LATAM, particularly in Mexico.

Periodontitis-Related Knowledge and Its Relationship with Oral Health Behavior among Adult Patients Seeking Professional Periodontal Care

Background: Periodontitis is a chronic inflammatory disease that not only damages the stomatognathic system, but may also adversely influence other systems and organs. Patients with low oral health literacy levels are more prone to gingivitis/periodontitis and have a more severe disease course. Methods: A written questionnaire was carried out to assess the knowledge of patients of the Outpatient Clinic of Department of Periodontal and Oral Mucosa Diseases, Medical University of Bialystok, Poland. The questions concerned knowledge regarding the causes of periodontal disease, its risk factors, and the connection between periodontal disease and general health status. To analyze the population, patients were divided according to gender, age and if they were first-time or regular outpatients. Results: Written questionnaires were completed by a total of 302 patients. In the studied population, we noted knowledge deficits, particularly related to weaker periodontal disease risk factors (stress, diabetes, osteoporosis, obesity) and the genetic factor, which is the determinant of periodontitis. The patients’ awareness of the role of plaque bacteria and the effect of smoking on the periodontium was at a relatively high level. The respondents were also aware of the impact of periodontal disease on general health as well as the role of oral hygiene in preventing the disease. At the same time, few of them (26%) used interdental brushes or an irrigator (8%). Conclusions: We demonstrated that patients have an insufficient level of knowledge related to risk factors as well as the prevention of periodontal disease. Awareness of the extent of oral health literacy among patients will help to identify key issues connected with health education interventions

Number of teeth lost on diet quality and glycemic control in patients with type 2 diabetes mellitus

OBJECTIVE

To describe the oral health profile and evaluate the impact of tooth loss on diet quality and glycemic control among 66 patients with type 2 diabetes (T2DM) treated in an endocrinology outpatient clinic at a teaching hospital.

METHODS

Questionnaires about diabetes self-care (SDSCA), masticatory ability, diet quality, anxiety level about dental treatment, and oral health were applied. Laboratory tests were retrieved from medical records or newly collected samples.

RESULTS

The presence of fewer than 21 teeth was associated with an unsatisfactory self-perceived masticatory ability (r = 0.44; p = 0.007). Most participants reported not having received guidance on oral health from their endocrinologists (81.8%) and having had the last visit to the dentist 2 years or more before the study (36.8%). The mean HbA1c level in the group with fewer than 21 teeth was comparable to that in the group with functional dentition (8.9 ± 1.5 and 8.7 ± 1.6%, respectively; p = 0.60).

CONCLUSION

Adults with T2DM have a high prevalence of tooth loss and lack of information about oral hygiene care. Our results reinforce the need for more effective communication between medical and dental care teams.

Interconnection of periodontal disease and comorbidities: Evidence, mechanisms, and implications

Periodontitis, a microbiome-driven inflammatory disease of the tooth-attachment apparatus, is epidemiologically linked with other disorders, including cardio-metabolic, cognitive neurodegenerative and autoimmune diseases, respiratory infections, and certain cancers. These associations may, in part, be causal, as suggested by interventional studies showing that local treatment of periodontitis reduces systemic inflammation and surrogate markers of comorbid diseases. The potential cause-and-effect connection between periodontitis and comorbidities is corroborated by studies in preclinical models of disease, which additionally provided mechanistic insights into these associations. This overview discusses recent advances in our understanding of the periodontitis-systemic disease connection, which may potentially lead to innovative therapeutic options to reduce the risk of periodontitis-linked comorbidities.

Maladaptive trained immunity and clonal hematopoiesis as potential mechanistic links between periodontitis and inflammatory comorbidities

Periodontitis is bidirectionally associated with systemic inflammatory disorders. The prevalence and severity of this oral disease and linked comorbidities increases with aging. Here, we review two newly emerged concepts, trained innate immunity (TII) and clonal hematopoiesis of indeterminate potential (CHIP), which together support a potential hypothesis on how periodontitis affects and is affected by comorbidities and why the susceptibility to periodontitis and comorbidities increases with aging. Given that chronic diseases are largely triggered by the action of inflammatory immune cells, modulation of their bone marrow precursors, the hematopoietic stem and progenitor cells (HSPCs), may affect multiple disorders that emerge as comorbidities. Such alterations in HSPCs can be mediated by TII and/or CHIP, two non-mutually exclusive processes sharing a bias for enhanced myelopoiesis and production of innate immune cells with heightened proinflammatory potential. TII is a state of elevated immune responsiveness based on innate immune (epigenetic) memory. Systemic inflammation can initiate TII in the bone marrow via sustained rewiring of HSPCs, which thereby display a skewing toward the myeloid lineage, resulting in generation of hyper-reactive or "trained" myeloid cells. CHIP arises from aging-related somatic mutations in HSPCs, which confer a survival and proliferation advantage to the mutant HSPCs and give rise to an outsized fraction of hyper-inflammatory mutant myeloid cells in the circulation and tissues. This review discusses emerging evidence that supports the notion that TII and CHIP may underlie a causal and age-related association between periodontitis and comorbidities. A holistic mechanistic understanding of the periodontitis-systemic disease connection may offer novel diagnostic and therapeutic targets for treating inflammatory comorbidities.

Links between Insulin Resistance and Periodontal Bacteria: Insights on Molecular Players and Therapeutic Potential of Polyphenols

Type 2 diabetes is a metabolic disease mainly associated with insulin resistance during obesity and constitutes a major public health problem worldwide. A strong link has been established between type 2 diabetes and periodontitis, an infectious dental disease characterized by chronic inflammation and destruction of the tooth-supporting tissue or periodontium. However, the molecular mechanisms linking periodontal bacteria and insulin resistance remain poorly elucidated. This study aims to summarize the mechanisms possibly involved based on in vivo and in vitro studies and targets them for innovative therapies. Indeed, during periodontitis, inflammatory lesions of the periodontal tissue may allow periodontal bacteria to disseminate into the bloodstream and reach tissues, including adipose tissue and skeletal muscles that store glucose in response to insulin. Locally, periodontal bacteria and their components, such as lipopolysaccharides and gingipains, may deregulate inflammatory pathways, altering the production of pro-inflammatory cytokines/chemokines. Moreover, periodontal bacteria may promote ROS overproduction via downregulation of the enzymatic antioxidant defense system, leading to oxidative stress. Crosstalk between players of inflammation and oxidative stress contributes to disruption of the insulin signaling pathway and promotes insulin resistance. In parallel, periodontal bacteria alter glucose and lipid metabolism in the liver and deregulate insulin production by pancreatic β-cells, contributing to hyperglycemia. Interestingly, therapeutic management of periodontitis reduces systemic inflammation markers and ameliorates insulin sensitivity in type 2 diabetic patients. Of note, plant polyphenols exert anti-inflammatory and antioxidant activities as well as insulin-sensitizing and anti-bacterial actions. Thus, polyphenol-based therapies are of high interest for helping to counteract the deleterious effects of periodontal bacteria and improve insulin resistance.

Association between Pre-Pregnancy BMI and Inflammatory Profile Trajectories during Pregnancy and Postpartum in Brazilian Women with Periodontitis: The IMPROVE Trial

This study aimed to explore the association between pre-pregnancy BMI and longitudinal changes in inflammatory markers from the second trimester of pregnancy to 6-8 weeks postpartum in women with periodontitis. This is a secondary exploratory analysis of 68 women who took part in a feasibility clinical trial in Rio de Janeiro, Brazil. Inflammatory markers included C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-10 (IL-10), and matrix metalloproteinase-9 (MMP-9) blood concentrations at 11-22 (T0) and 30-36 gestational weeks (T1), and 6-8 weeks postpartum (T3). Longitudinal generalised linear mixed-effects models were used to identify possible associations between pre-pregnancy BMI and changes in concentrations of inflammatory markers. Pre-pregnancy excess weight (β = 4.39; 95% CI, 2.12-6.65) was significantly associated with increased CRP levels from pregnancy to postpartum. There were no significant associations between pre-pregnancy BMI and longitudinal changes in IL-6, IL-10 and MMP-9. Our findings provide evidence that a higher pre-pregnancy BMI may lead to increases in CRP levels during pregnancy in women with periodontitis, irrespective of the severity of clinical periodontal parameters. Further studies need to investigate if predictors of changes in inflammatory markers can be used as prognostic factors for gestational outcomes.

Antibodies to Porphyromonas gingivalis Are Increased in Patients with Severe Periodontitis, and Associate with Presence of Specific Autoantibodies and Myocardial Infarction

There is accumulating data suggesting that periodontitis is associated with increased risk of systemic and autoimmune diseases, including cardiovascular disease, rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), and there is an unmet need to identify these individuals early. With the periodontal bacteria Porphyromonas gingivalis (Pg) as one of the key drivers of periodontitis, we set out to investigate whether antibodies to Pg virulence factor arginine gingipain (Rgp) could serve as a biomarker for periodontitis patients at increased risk of autoimmunity and systemic disease. We measured serum anti-Rgp IgG in three study populations: PAROKRANK (779 individuals with myocardial infarction (MI); 719 controls), where 557 had periodontitis, and 312 were positive for autoantibodies associated with RA/SLE; the PerioGene North pilot (41 periodontitis; 39 controls); and an SLE case/control study (101 SLE; 100 controls). Anti-Rgp IgG levels were increased in severe periodontitis compared to controls (p < 0.0001), in individuals positive for anti-citrullinated protein antibodies (p = 0.04) and anti-dsDNA antibodies (p = 0.035), compared to autoantibody-negative individuals; and in MI patients versus matched controls (p = 0.035). Our data support longitudinal studies addressing the role of anti-Rgp antibodies as biomarkers for periodontitis patients at increased risk of developing autoimmunity linked to RA and SLE, and mechanisms underpinning these associations.

Unexpected Relationships: Periodontal Diseases: Atherosclerosis-Plaque Destabilization? From the Teeth to a Coronary Event

Atherosclerotic cardiovascular disease (ASCVD) and periodontal disease (PD) are global health problems. High frequency of ASCVD is associated with the spread of many risk factors, including poor diet, sedentary lifestyle, diabetes, hyperlipidemia, obesity, smoking, hypertension, chronic kidney disease, hypertension, hyperhomocysteinemia, hyperuricemia, excessive stress, virus infection, genetic predisposition, etc. The pathogenesis of ASCVD is complex, while inflammation plays an important role. PD is a chronic, multifactorial inflammatory disease caused by dysbiosis of the oral microbiota, causing the progressive destruction of the bone and periodontal tissues surrounding the teeth. The main etiological factor of PD is the bacteria, which are capable of activating the immune response of the host inducing an inflammatory response. PD is associated with a mixed microbiota, with the evident predominance of anaerobic bacteria and microaerophilic. The "red complex" is an aggregate of three oral bacteria: Tannerella forsythia Treponema denticola and Porphyromonas gingivalis responsible for severe clinical manifestation of PD. ASCVD and PD share a number of risk factors, and it is difficult to establish a causal relationship between these diseases. The influence of PD on ASCVD should be treated as a factor increasing the risk of atherosclerotic plaque destabilization and cardiovascular events. The results of observational studies indicate that PD significantly increases the risk of ASCVD. In interventional studies, PD treatment was found to have a beneficial effect in the prevention and control of ASCVD. This comprehensive review summarizes the current knowledge of the relationship between PD and ASCVD.

Interplay Among the Oral Microbiome, Oral Cavity Conditions, the Host Immune Response, Diabetes Mellitus, and Its Associated-Risk Factors-An Overview

This comprehensive review of the literature aimed to investigate the interplay between the oral microbiome, oral cavity conditions, and host immune response in Diabetes mellitus (DM). Moreover, this review also aimed to investigate how DM related risk factors, such as advanced age, hyperglycemia, hyperlipidemia, obesity, hypertension and polycystic ovary syndrome (PCOS), act in promoting or modifying specific mechanisms that could potentially perpetuate both altered systemic and oral conditions. We found that poorly controlled glycemic index may exert a negative effect on the immune system of affected individuals, leading to a deficient immune response or to an exacerbation of the inflammatory response exacerbating DM-related complications. Hyperglycemia induces alterations in the oral microbiome since poor glycemic control is associated with increased levels and frequencies of periodontal pathogens in the subgingival biofilm of individuals with DM. A bidirectional relationship between periodontal diseases and DM has been suggested: DM patients may have an exaggerated inflammatory response, poor repair and bone resorption that aggravates periodontal disease whereas the increased levels of systemic pro-inflammatory mediators found in individuals affected with periodontal disease exacerbates insulin resistance. SARS-CoV-2 infection may represent an aggravating factor for individuals with DM. Individuals with DM tend to have low salivary flow and a high prevalence of xerostomia, but the association between prevalence/experience of dental caries and DM is still unclear. DM has also been associated to the development of lesions in the oral mucosa, especially potentially malignant ones and those associated with fungal infections. Obesity plays an important role in the induction and progression of DM. Co-affected obese and DM individuals tend to present worse oral health conditions. A decrease in HDL and, an increase in triglycerides bloodstream levels seem to be associated with an increase on the load of periodontopathogens on oral cavity. Moreover, DM may increase the likelihood of halitosis. Prevalence of impaired taste perception and impaired smell recognition tend to be greater in DM patients. An important interplay among oral cavity microbiome, DM, obesity and hypertension has been proposed as the reduction of nitrate into nitrite, in addition to contribute to lowering of blood pressure, reduces oxidative stress and increases insulin secretion, being these effects desirable for the control of obesity and DM. Women with PCOS tend to present a distinct oral microbial composition and an elevated systemic response to selective members of this microbial community, but the association between oral microbiome, PCOS are DM is still unknown. The results of the studies presented in this review suggest the interplay among the oral microbiome, oral cavity conditions, host immune response and DM and some of the DM associated risk factors exist. DM individuals need to be encouraged and motivated for an adequate oral health care. In addition, these results show the importance of adopting multidisciplinary management of DM and of strengthening physicians-dentists relationship focusing on both systemic and on oral cavity conditions of DM patients.

The Relationships Among Periodontitis, Pneumonia and COVID-19

Periodontitis is a chronic inflammatory disease of the supporting structures of the teeth that affects approximately half of adults 30 years and older. There is increasing interest in the direct and indirect relationships between periodontitis and systemic diseases, including respiratory diseases. The aim of this study was to assess the evidence on links among periodontitis, pneumonia, and COVID-19. Oral and periodontal bacteria may be linked to respiratory disease directly by aspiration of pathogens into the lungs causing pneumonia. As SARS-CoV-2 began to spread worldwide in 2020, questions have arisen of how periodontal disease may also be connected to SARS-CoV-2 infection and severity, including potential replication and dissemination of the virus from periodontal pockets. Some proposed mechanisms include the oral cavity acting as a reservoir or point of entry for SARS-CoV-2, overgrowth of periodontal pathogens, and increased production of proinflammatory cytokines. Due to potential links between periodontal disease and respiratory infections like pneumonia and SARS-CoV-2, oral hygiene and management of periodontitis remain essential to help reduce infection and transmission of SARS-CoV-2.

Oral Health and Liver Disease: Bidirectional Associations—A Narrative Review

Several links between chronic liver disease and oral health have been described and are discussed in this narrative review. Oral manifestations such as lichen planus, ulcers, xerostomia, erosion and tongue abnormalities seem to be particularly prevalent among patients with chronic liver disease. These may be causal, coincidental, secondary to therapeutic interventions, or attributable to other factors commonly observed in liver disease patients. In addition, findings from both experimental and epidemiological studies suggest that periodontitis can induce liver injury and contribute to the progression of chronic liver disease through periodontitis-induced systemic inflammation, endotoxemia, and gut dysbiosis with increased intestinal translocation. This has brought forward the hypothesis of an oral-gut-liver axis. Preliminary clinical intervention studies indicate that local periodontal treatments may lead to beneficial liver effects, but more human studies are needed to clarify if treatment of periodontitis truly can halt or reverse progression of liver disease and improve liver-related outcomes.

Novel Insight into the Mechanisms of the Bidirectional Relationship between Diabetes and Periodontitis

Periodontitis and diabetes are two major global health problems despite their prevalence being significantly underreported and underestimated. Both epidemiological and intervention studies show a bidirectional relationship between periodontitis and diabetes. The hypothesis of a potential causal link between the two diseases is corroborated by recent studies in experimental animals that identified mechanisms whereby periodontitis and diabetes can adversely affect each other. Herein, we will review clinical data on the existence of a two-way relationship between periodontitis and diabetes and discuss possible mechanistic interactions in both directions, focusing in particular on new data highlighting the importance of the host response. Moreover, we will address the hypothesis that trained immunity may represent the unifying mechanism explaining the intertwined association between diabetes and periodontitis. Achieving a better mechanistic insight on clustering of infectious, inflammatory, and metabolic diseases may provide new therapeutic options to reduce the risk of diabetes and diabetes-associated comorbidities.

Incidence of Arterial Hypertension in People With Periodontitis and Characterization of the Oral and Subgingival Microbiome: A Study Protocol

Cardiovascular diseases are the leading cause of morbidity and mortality worldwide. High blood pressure in particular, continues to increase throughout the global population at an increasingly fast pace. The relationship between arterial hypertension and periodontitis has been recently discussed in the context of its origins and implications. Particularly relevant is the role of the periodontal microbiome linked to persistent local and systemic inflammation, along with other risk factors and social determinants of health. The present protocol will investigate/assess the association between periodontal disease and its microbiome on the onset of hypertension, within a cohort from Mexico City. One thousand two hundred twelve participants will be studied during a 60-month period. Studies will include analysis of periodontal conditions, sampling and sequencing of the salivary and subgingival microbiome, interviews on nutritional and lifestyle habits, social determinants of health, blood pressure and anthropometric measurements. Statistical associations and several classic epidemiology and machine learning approaches will be performed to analyze the data. Implications for the generation of public policy—by early public health interventions or epidemiological surveillance approaches—and for the population empowerment—via the establishment of primary prevention recommendations, highlighting the relationship between oral and cardiovascular health—will be considered. This latter set of interventions will be supported by a carefully planned science communication and health promotion strategy. This study has been registered and approved by the Research and Ethics Committee of the School of Dentistry, Universidad Nacional Autónoma de México (CIE/0308/05/2019) and the National Institute of Genomic Medicine (CEI/2020/12). The umbrella cohort was approved by the Institutional Bioethics Committee of the National Institute of Cardiology-Ignacio Chavez (INC-ICh) under code 13-802.

C3-targeted host-modulation approaches to oral inflammatory conditions

Periodontitis is an inflammatory disease caused by biofilm accumulation and dysbiosis in subgingival areas surrounding the teeth. If not properly treated, this oral disease may result in tooth loss and consequently poor esthetics, deteriorated masticatory function and compromised quality of life. Epidemiological and clinical intervention studies indicate that periodontitis can potentially aggravate systemic diseases, such as, cardiovascular disease, type 2 diabetes mellitus, rheumatoid arthritis, and Alzheimer disease. Therefore, improvements in the treatment of periodontal disease may benefit not only oral health but also systemic health. The complement system is an ancient host defense system that plays pivotal roles in immunosurveillance and tissue homeostasis. However, complement has unwanted consequences if not controlled appropriately or excessively activated. Complement overactivation has been observed in patients with periodontitis and in animal models of periodontitis and drives periodontal inflammation and tissue destruction. This review places emphasis on a promising periodontal host-modulation therapy targeting the complement system, namely the complement C3-targeting drug, AMY-101. AMY-101 has shown safety and efficacy in reducing gingival inflammation in a recent Phase 2a clinical study. We also discuss the potential of AMY-101 to treat peri-implant inflammatory conditions, where complement also seems to be involved and there is an urgent unmet need for effective treatment.

Candidate loci shared among periodontal disease, diabetes and bone density

INTRODUCTION

While periodontal disease (PD) has been associated with type 2 diabetes (T2D) and osteoporosis, the underlying genetic mechanisms for these associations remain largely unknown. The aim of this study is to apply cross-trait genetic analyses to investigate the potentially shared biology among PD, T2D, and bone mineral density (BMD) by assessing pairwise genetic correlations and searching for shared polymorphisms.

METHODS

We applied cross-trait genetic analyses leveraging genome-wide association study (GWAS) summary statistics for: Periodontitis/loose teeth from the UKBB/GLIDE consortium (PerioLT, N=506594), T2D from the DIAGRAM consortium (N_eff=228825), and BMD from the GEFOS consortium (N=426824). Among all three, pair-wise genetic correlations were estimated with linkage disequilibrium (LD) score regression. Multi-trait meta-analysis of GWAS (MTAG) and colocalization analyses were performed to discover shared genome-wide significant variants (p_MTAG <5x10^-8). For replication, we conducted independent genetic analyses in the Women's Genome Health Study (WGHS), a prospective cohort study of middle-aged women of whom 14711 provided self-reported periodontal disease diagnosis, oral health measures, and periodontal risk factor data including incident T2D.

RESULTS

Significant genetic correlations were identified between PerioLT/T2D (Rg=0.23; SE=0.04; p=7.4e^-09) and T2D/BMD (Rg=0.09; SE=0.02; p=9.8e^-06). Twenty-one independent pleiotropic variants were identified via MTAG (p_MTAG<5x10^-8 across all traits). Of these variants, genetic signals for PerioLT and T2D colocalized at one candidate variant (rs17522122; Prob_{H4 =} 0.58), a 3'UTR variant of AKAP6. Colocalization between T2D/BMD and the original PerioLT GWAS p-values suggested 14 additional loci. In the independent WGHS sample, which includes responses to a validated oral health questionnaire for PD surveillance, the primary shared candidate (rs17522122) was associated with less frequent dental flossing [OR(95%CI)= 0.92 (0.87-0.98), p=0.007], a response that is correlated with worse PD status. Moreover, 4 additional candidate variants were indirectly supported by associations with less frequent dental flossing [rs75933965, 1.17(1.04-1.31), p=0.008], less frequent dental visits [rs77464186, 0.82(0.75-0.91), p=0.0002], less frequent dental prophylaxis [rs67111375, 0.91(0.83-0.99), p=0.03; rs77464186, 0.80(0.72-0.89), p=3.8e^-05], or having bone loss around teeth [rs8047395, 1.09(1.03-1.15), p=0.005].

DISCUSSION

This integrative approach identified one colocalized locus and 14 additional candidate loci that are shared between T2D and PD/oral health by comparing effects across PD, T2D and BMD. Future research is needed to independently validate our findings.

4. Comprehensive Medical Evaluation and Assessment of Comorbidities: Standards of Medical Care in Diabetes-2022

The American Diabetes Association (ADA) "Standards of Medical Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee (https://doi.org/10.2337/dc22-SPPC), are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations, please refer to the Standards of Care Introduction (https://doi.org/10.2337/dc22-SINT). Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Ligature induced periodontitis in rats causes gut dysbiosis leading to hepatic injury through SCD1/AMPK signalling pathway

AIMS

Previous studies have demonstrated that chronic periodontitis (CP) is closely associated with the occurrence and development of a variety of systemic diseases. In this study, we successfully constructed a rat CP model through dental silk ligation, and the corresponding inflammatory reactions and fatty lesions were observed in the liver.

MAIN METHODS

Sprague-Dawley rats (n = 6) underwent tooth ligation at the bilateral first molars with silk thread to induce CP and were sacrificed 8 weeks later and compared to non-ligated rats (n = 6). RNA sequencing and 16S rRNA analysis were performed to determine the molecular mechanisms of CP involved in inducing liver disease. Alveolar bone loss, liver enzymes, mandible and liver histopathology, and inflammatory responses were compared between groups.

KEY FINDINGS

RNA sequencing of liver tissue showed that the expression of SCD1 increased significantly in CP rats compared to controls. KEGG enrichment analysis showed that the AMPK signalling pathway may be involved in liver steatosis. The intestinal flora of faecal samples of rats were analysed by 16S rRNA sequencing, and the results indicated that the intestinal flora of the CP group was evidently imbalanced. The expression levels of tight junction proteins (ZO-1, occludin, and claudin-1) were significantly reduced in CP rats. Meanwhile, increases in serum IL-1β and lipopolysaccharide in CP rats reflected a systemic inflammatory response.

SIGNIFICANCE

CP may be involved in the occurrence and development of hepatic injury and liver steatosis, and its mechanism may be related to the oral-gut-liver axis and SCD1/AMPK signal activation in the liver.

Mendelian randomization supports the causal role of fasting glucose on periodontitis

PURPOSE

The effect of hyperglycemia on periodontitis is mainly based on observational studies, and inconsistent results were found whether periodontal treatment favors glycemic control. The two-way relationship between periodontitis and hyperglycemia needs to be further elucidated. This study aims to evaluate the causal association of periodontitis with glycemic traits using bi-directional Mendelian randomization (MR) approach.

METHODS

Summary statistics were sourced from large-scale genome-wide association study conducted for fasting glucose (N = 133,010), HbA1c (N = 123,665), type 2 diabetes (T2D, N = 659,316), and periodontitis (N = 506,594) among European ancestry. The causal relationship was estimated using the inverse-variance weighted (IVW) model and further validated through extensive complementary and sensitivity analyses.

RESULTS

Overall, IVW showed that a genetically higher level of fasting glucose was significantly associated with periodontitis (OR = 1.119; 95% CI = 1.045-1.197; P_FDR= 0.007) after removing the outlying instruments. Such association was robust and consistent through other MR models. Limited evidence was found suggesting the association of HbA1C with periodontitis after excluding the outliers (IVW OR = 1.123; 95% CI = 1.026-1.229; P_FDR= 0.048). These linkages remained statistically significant in multivariate MR analyses, after adjusting for body mass index. The reverse direction MR analyses did not exhibit the causal association of genetic liability to periodontitis with any of the glycemic trait tested.

CONCLUSIONS

Our MR study reaffirms previous findings and extends evidence to substantiate the causal effect of hyperglycemia on periodontitis. Future studies with robust genetic instruments are needed to confirm the causal association of periodontitis with glycemic traits.

Burden of chronic diseases associated with periodontal diseases: a retrospective cohort study using UK primary care data

OBJECTIVES

To identify the association between periodontal diseases (gingivitis and periodontitis) and chronic diseases including cardiovascular disease, cardiometabolic disease, autoimmune disease and mental ill health.

DESIGN

Retrospective cohort.

SETTING

IQVIA Medical Research Data-UK between 1 January 1995 and 1 January 2019.

PARTICIPANTS

64 379 adult patients with a general practitioner recorded diagnosis of periodontal disease (exposed patients) were matched to 251 161 unexposed patients by age, sex, deprivation and registration date.

MAIN OUTCOME MEASURES

Logistic regression models accounting for covariates of clinical importance were undertaken to estimate the adjusted OR (aOR) of having chronic diseases at baseline in the exposed compared with the unexposed group. Incidence rates for each outcome of interest were then provided followed by the calculation of adjusted HRs using cox regression modelling to describe the risk of outcome development in each group.

RESULTS

The average age at cohort entry was 45 years and the median follow-up was 3.4 years. At study entry, the exposed cohort had an increased likelihood of having a diagnosis of cardiovascular disease (aOR 1.43; 95% CI 1.38 to 1.48), cardiometabolic disease (aOR 1.16; 95% CI 1.13 to 1.19), autoimmune disease (aOR 1.33; 95% CI 1.28 to 1.37) and mental ill health (aOR 1.79; 95% CI 1.75 to 1.83) compared with the unexposed group. During the follow-up of individuals without pre-existing outcomes of interest, the exposed group had an increased risk of developing cardiovascular disease (HR 1.18; 95% CI 1.13 to 1.23), cardiometabolic disease (HR 1.07; 95% CI 1.03 to 1.10), autoimmune disease (HR 1.33; 95% CI 1.26 to 1.40) and mental ill health (HR 1.37; 95% CI 1.33 to 1.42) compared with the unexposed group.

CONCLUSIONS

In this cohort, periodontal diseases appeared to be associated with an increased risk of developing cardiovascular, cardiometabolic, autoimmune diseases and mental ill health. Periodontal diseases are very common; therefore, an increased risk of other chronic diseases represent a substantial public health burden.

LncRNA LOXL1-AS1 inhibits proliferation of PDLSCs and downregulates IL-1β in periodontitis patients

BACKGROUND

The carcinogenic role of lncRNA LOXL1-AS1 in thoracic aortic aneurysm has been confirmed, but its role in the pathogenesis of periodontitis remains unclear. Our preliminary deep sequencing data revealed LOXL1-AS1 downregulation in periodontitis and its inverse correlation with IL-1β, a critical inflammatory mediator in periodontitis. This study was therefore performed to investigate the potential interaction between LOXL1-AS1 and IL-1β in periodontitis.

METHODS

The study included 30 periodontitis patients (18 males and 12 females at the age of 34 to 44 years, with a mean of 39.3 ± 2.1 years) and 30 healthy controls (18 males and 12 females at the age of 33 to 44 years with a mean of 39.2 ± 2.0 years). The effects of LOXL1-AS1 overexpression on IL-1β were evaluated by RT-qPCR and Western blot. CCK-8 assay was used to analyze cell proliferation.

RESULTS

LOXL1-AS1 was downregulated in periodontitis-affected periodontal ligament stem cells (PDLSCs) compared with healthy PDLSCs, while IL-1β was upregulated in periodontitis-affected PDLSCs and was inversely correlated with LOXL1-AS1. LOXL1-AS1 overexpression mediated IL-1β downregulation in PDLSCs. IL-1β treatment did not affect LOXL1-AS1 expression. Moreover, LOXL1-AS1 overexpression inhibited the proliferation of periodontitis-affected PDLSCs. LOXL1-AS1 overexpression and IL-1β knockdown increased Bax/Bcl-2 ratio and caspase-3 level.

CONCLUSION

This study is the first to report LOXL1-AS1 downregulation in periodontitis. Moreover, LOXL1-AS1 might inhibit the proliferation of periodontitis-affected PDLSCs and downregulate IL-1β to improve periodontitis.

Effect of periodontal treatments on blood pressure

BACKGROUND

An association has been hypothesized between periodontitis and hypertension. Periodontal therapy is believed to reduce systemic inflammatory mediators and increase endothelial function, thus having the potential to prevent and treat hypertension.

OBJECTIVES

To assess the effect and safety of different periodontal treatment modalities on blood pressure (BP) in people with chronic periodontitis.

SEARCH METHODS

The Cochrane Hypertension Information Specialist searched for randomized controlled trials (RCTs) up to November 2020 in the Cochrane Hypertension Specialised Register, CENTRAL, MEDLINE, Embase, seven other databases, and two clinical trials registries. We contacted the authors of relevant papers regarding further published and unpublished work.

SELECTION CRITERIA

RCTs and quasi-RCTs aiming to detect the effect of periodontal treatment on BP were eligible. Participants should have been diagnosed with chronic periodontitis and hypertension (or no hypertension if the study explored the preventive effect of periodontal treatment). Participants in the intervention group should have undergone subgingival scaling and root planing (SRP) and any other type of periodontal treatments, compared with either no periodontal treatment or alternative periodontal treatment in the control group.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane for study identification, data extraction, and risk of bias assessment. We used a formal pilot-tested data extraction form for data extraction, and the Cochrane risk of bias tool for risk of bias assessment. We planned the meta-analysis, test for heterogeneity, sensitivity analysis, and subgroup analysis. We assessed the certainty of evidence using GRADE. The primary outcome was change in systolic BP (SBP) and diastolic BP (DBP).

MAIN RESULTS

We included eight RCTs. Five had low risk of bias, one had unclear risk of bias, and two had high risk of bias. Four trials compared periodontal treatment with no treatment. We found no evidence of a difference in the short-term change of SBP and DBP for people diagnosed with periodontitis and other cardiovascular diseases except hypertension (very low-certainty evidence). We found no evidence of a difference in long-term changes in SBP (mean difference [MD] -2.25 mmHg, 95% confidence interval [CI] -9.41 to 4.92; P = 0.54; studies = 2, participants = 108; low-certainty evidence) and DBP (MD -2.55 mmHg, 95% CI -6.90 to 1.80; P = 0.25; studies = 2, participants = 103; low-certainty evidence). Concerning people diagnosed with periodontitis, in the short term, two studies of low certainty reported no changes in SBP (MD -0.14 mmHg, 95% CI -4.05 to 3.77; P = 0.94; participants = 294) and DBP (MD -0.15 mmHg, 95% CI -2.47 to 2.17; P = 0.90; participants = 294), and we found no evidence of a difference in SBP and DBP over a long period based on low certainty of evidence. Three studies compared intensive periodontal treatment with supra-gingival scaling. We found no evidence of a difference in changes in SBP and DBP for any length of time in people diagnosed with periodontitis (very low-certainty evidence). In people diagnosed with periodontitis and hypertension, we found one study reporting a significant reduction in the short term in SBP (MD -11.20 mmHg, 95% CI -15.40 to -7.00; P < 0.001; participants = 101; moderate-certainty evidence) and DBP (MD -8.40 mmHg, 95% CI -12.19 to -4.61; P < 0.0001; participants = 101; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

We found no evidence of a difference of an impact of periodontal treatments on BP in most comparisons assessed in this review, and given the low certainty of evidence and the lack of relevant studies we could not draw conclusions about the effect of periodontal treatment on BP in people with chronic periodontitis. We found only one study suggesting that periodontal treatment may reduce SBP and DBP over a short period in people with hypertension and chronic periodontitis, but the certainty of evidence was moderate.

Periodontal Disease: The Good, The Bad, and The Unknown

Periodontal disease is classically characterized by progressive destruction of the soft and hard tissues of the periodontal complex, mediated by an interplay between dysbiotic microbial communities and aberrant immune responses within gingival and periodontal tissues. Putative periodontal pathogens are enriched as the resident oral microbiota becomes dysbiotic and inflammatory responses evoke tissue destruction, thus inducing an unremitting positive feedback loop of proteolysis, inflammation, and enrichment for periodontal pathogens. Keystone microbial pathogens and sustained gingival inflammation are critical to periodontal disease progression. However, recent studies have revealed the importance of previously unidentified microbes involved in disease progression, including various viruses, phages and bacterial species. Moreover, newly identified immunological and genetic mechanisms, as well as environmental host factors, including diet and lifestyle, have been discerned in recent years as further contributory factors in periodontitis. These factors have collectively expanded the established narrative of periodontal disease progression. In line with this, new ideologies related to maintaining periodontal health and treating existing disease have been explored, such as the application of oral probiotics, to limit and attenuate disease progression. The role of systemic host pathologies, such as autoimmune disorders and diabetes, in periodontal disease pathogenesis has been well noted. Recent studies have additionally identified the reciprocated importance of periodontal disease in potentiating systemic disease states at distal sites, such as in Alzheimer's disease, inflammatory bowel diseases, and oral cancer, further highlighting the importance of the oral cavity in systemic health. Here we review long-standing knowledge of periodontal disease progression while integrating novel research concepts that have broadened our understanding of periodontal health and disease. Further, we delve into innovative hypotheses that may evolve to address significant gaps in the foundational knowledge of periodontal disease.

External validation of a rapid, non-invasive tool for periodontitis screening in a medical care setting

OBJECTIVES

Medical professionals should advise their patients to visit a dentist if necessary. Due to the lack of time and knowledge, screening for periodontitis is often not done. To alleviate this problem, a screening model for total (own teeth/gum health, gum treatment, loose teeth, mouthwash use, and age)/severe periodontitis (gum treatment, loose teeth, tooth appearance, mouthwash use, age, and sex) in a medical care setting was developed in the Academic Center of Dentistry Amsterdam (ACTA) [1]. The purpose of the present study was to externally validate this tool in an outpatient medical setting.

MATERIALS AND METHODS

Patients were requited in an outpatient medical setting as the validation cohort. The self-reported oral health questionnaire was conducted, demographic data were collected, and periodontal examination was performed. Algorithm discrimination was expressed as the area under the receiver operating characteristic curve (AUROCC). Sensitivity, specificity, and positive and negative predictive values were calculated. Calibration plots were made.

RESULTS

For predicting total periodontitis, the AUROCC was 0.59 with a sensitivity of 49% and specificity of 68%. The PPV was 57% and the NPV scored 55%. For predicting severe periodontitis, the AUROCC was 0.73 with a sensitivity of 71% and specificity of 63%. The PPV was 39% and the NPV 87%.

CONCLUSIONS

The performance of the algorithm for severe periodontitis is found to be sufficient in the current medical study population. Further external validation of periodontitis algorithms in non-dental school populations is recommended.

CLINICAL RELEVANCE

Because general physicians are obligated to screen patients for periodontitis, it is our general goal that they can use a prediction model in medical settings without an oral examination.

Effects of l-arginine and l-ornithine supplementations on the treatment of chronic periodontitis: A preliminary randomized short-term clinical trial

The growing interest in the possibilities of modulating macrophages in inflammatory diseases with therapeutic purpose has prompted the development of new approaches for the treatment of periodontitis. This randomized add-on open preliminary clinical study evaluated the short-term effects of L-arginine or L-ornithine as an adjuvant to scaling and root planing (SRP) in patients with chronic periodontitis.

Materials and methods

Seventy-five periodontitis patients were recruited and monitored clinically and immunologically at baseline (before SRP) and 30 ± 5 days after SRP. All patients were assigned by stratified randomization to SRP (SRP only, n = 25), Arg (SRP + L-arginine, n = 25) or Control (SRP + L-ornithine, n = 25) Group. The medicines were used according to available instructions for 10 and 15 days, respectively. During the study, all patients were on a stable diet, without changing their rations and regiments. As immunological monitoring immunohistochemical study of CD68+ and CD163 + single positive gingival macrophages for 5 patients per group in the same time-point was conducted. The data were statistically analyzed.

Results

Reduction of periodontal pocket depth (PPD) and bleeding on probing (BoP) was observed in all groups, with significant between-group differences for BoP in the Arg Group (p < 0.0001) at 30 days. The SRP and Arg groups demonstrated nonsignificantly increased density of CD68+ and CD163 + cells. The Orn Group showed an increase in the density of CD68+ and CD163 + macrophages at intragroup (p = 0.0066 and p < 0.0001) and between-group levels (p = 0.001 and p < 0.0001), and these changes corresponded to clinical PPD and BoP reduction. In the Arg and Orn groups at 30 days, CD163 + macrophages significantly predominated over CD68+ (p = 0.013, p < 0.0001).

Conclusion

The use of L-arginine and L-ornithine as an adjunct to SRP promotes additional limited immunological benefit in the treatment of periodontitis. Metabolic stimulation with L-ornithine, but not L-arginine, is preferable for CD163+ Mφs subpopulation in periodontitis-affected gingiva.

Association between maternal periodontal disease and adverse pregnancy outcomes: an analysis of claims data

BACKGROUND

While a number of studies have explored the link between periodontal disease and adverse pregnancy outcomes, both epidemiological studies and intervention trials have reached contradictory results with relatively small sample sizes. Utilizing large-scale claims data, we aim to investigate the association between maternal periodontal disease and adverse pregnancy outcomes.

OBJECTIVE

Utilizing large-scale claims data, we aim to investigate the association between maternal periodontal disease and adverse pregnancy outcomes.

METHODS

Using de-identified claims data from a national commercial insurer in the USA, records of all observed pregnancies from 2015 to 2019 were included in this retrospective cohort study. Adverse pregnancy outcomes, including low birthweight (LBW) of the newborn, preterm birth (PTB) and spontaneous abortion, were primary outcomes. To evaluate the association between periodontal disease and pregnancy outcomes, logistic mixed-effect model was estimated with periodontal disease status, age, existing clinical conditions of mothers and geographic location as covariates.

RESULTS

Out of 748 792 observed pregnancy records, 18.66% resulted in adverse pregnancy outcomes; 5.92% in LBW, 14.46% in PTB and 2.22 % in spontaneous abortion. Adjusting for individual-level risk factors, periodontal disease was significantly associated with maternal complications with odds ratios of 1.19 (95% CI:1.15, 1.24) for any adverse pregnancy outcomes, 1.10 (95% CI:1.03, 1.17) for LBW, 1.15 (95% CI:1.10, 1.19) for PTB and 1.34 (95% CI:1.23, 1.46) for spontaneous abortions.

CONCLUSIONS

Maternal periodontal disease may be associated with an increased risk of maternal complications and neonatal morbidity. A timely diagnosis and treatment of periodontal disease during pregnancy should be encouraged by considering oral health as part of routine prenatal care.

Active matrix metalloproteinase-8: A potential biomarker of oral systemic link

OBJECTIVES

This mini review aims to address some possible gaps in periodontal diagnosis in clinical studies particularly involving the oral-systemic connection with a view to minimize such gaps, and thus improve patient treatment experiences and outcomes.

METHODS

The conventional assessment of periodontitis has traditionally been by clinical and radiographic oral parameters. We reviewed numerous studies published mainly within the past decade, to affirm the oral-systemic link, the contribution of periodontitis to the inflammatory burden in various systemic diseases and conditions, and the potential role of active matrix metalloproteinase-8 (aMMP-8).

RESULTS

While it is established that periodontal pathogens in dental plaque biofilm are the primary initiating agents in periodontitis, it has become clear from the appraisal of recent studies that the host inflammation, including biomarkers such as aMMP-8 play a major role, being the driving underlying pathological mechanism in both periodontitis and systemic diseases.

CONCLUSIONS

The apparent limitations of conventional diagnostic tools have led researchers to seek alternative methods of evaluation such as the quantification of biomarkers including aMMP-8, which can be a bridge between oral/periodontal and systemic diseases; aMMP-8 can form a mouth-body connection.