Control of tissue homeostasis by the extracellular matrix: Synthetic heparan sulfate as a promising therapeutic for periodontal health and bone regeneration.

Proteoglycans are core proteins associated with carbohydrate/sugar moieties that are highly variable in disaccharide composition, which dictates their function. These carbohydrates are named glycosaminoglycans, and they can be attached to proteoglycans or found free in tissues or on cell surfaces. Glycosaminoglycans such as hyaluronan, chondroitin sulfate, dermatan sulfate, keratan sulfate, and heparin/heparan sulfate have multiple functions including involvement in inflammation, immunity and connective tissue structure, and integrity. Heparan sulfate is a highly sulfated polysaccharide that is abundant in the periodontium including alveolar bone. Recent evidence supports the contention that heparan sulfate is an important player in modulating interactions between damage associated molecular patterns and inflammatory receptors expressed by various cell types. The structure of heparan sulfate is reported to dictate its function, thus, the utilization of a homogenous and structurally defined heparan sulfate polysaccharide for modulation of cell function offers therapeutic potential. Recently, a chemoenzymatic approach was developed to allow production of many structurally defined heparan sulfate carbohydrates. These oligosaccharides have been studied in various pathological inflammatory conditions to better understand their function and their potential application in promoting tissue homeostasis. We have observed that specific size and sulfation patterns can modulate inflammation and promote tissue maintenance including an anabolic effect in alveolar bone. Thus, new evidence provides a strong impetus to explore heparan sulfate as a potential novel therapeutic agent to treat periodontitis, support alveolar bone maintenance, and promote bone formation.

Development and External Validation of a Multivariable Prediction Model to Identify Nondiabetic Hyperglycemia and Undiagnosed Type 2 Diabetes: Diabetes Risk Assessment in Dentistry Score (DDS).

The aim of this study was to develop and externally validate a score for use in dental settings to identify those at risk of undiagnosed nondiabetic hyperglycemia (NDH) or type 2 diabetes (T2D). The Studies of Health in Pomerania (SHIP) project comprises 2 representative population-based cohort studies conducted in northeast Germany. SHIP-TREND-0, 2008 to 2012 (the development data set) had 3,339 eligible participants, with 329 having undiagnosed NDH or T2D. Missing data were replaced using multiple imputation. Potential covariates were selected for inclusion in the model using backward elimination. Heuristic shrinkage was used to reduce overfitting, and the final model was adjusted for optimism. We report the full model and a simplified paper-based point-score system. External validation of the model and score employed an independent data set comprising 2,359 participants with 357 events. Predictive performance, discrimination, calibration, and clinical utility were assessed. The final model included age, sex, body mass index, smoking status, first-degree relative with diabetes, presence of a dental prosthesis, presence of mobile teeth, history of periodontal treatment, and probing pocket depths ≥5 mm as well as prespecified interaction terms. In SHIP-TREND-0, the model area under the curve (AUC) was 0.72 (95% confidence interval [CI] 0.69, 0.75), calibration in the large was -0.025. The point score AUC was 0.69 (95% CI 0.65, 0.72), with sensitivity of 77.0 (95% CI 76.8, 77.2), specificity of 51.5 (95% CI 51.4, 51.7), negative predictive value of 94.5 (95% CI 94.5, 94.6), and positive predictive value of 17.0 (95% CI 17.0, 17.1). External validation of the point score gave an AUC of 0.69 (95% CI 0.66, 0.71), sensitivity of 79.2 (95% CI 79.0, 79.4), specificity of 49.9 (95% CI 49.8, 50.00), negative predictive value 91.5 (95% CI 91.5, 91.6), and positive predictive value of 25.9 (95% CI 25.8, 26.0). A validated prediction model involving dental variables can identify NDH or undiagnosed T2DM. Further studies are required to validate the model for different European populations.

Concordance of three point of care testing devices with clinical chemistry laboratory standard assays and patient-reported outcomes of blood sampling methods.

BACKGROUND: Point of care testing (POCT) devices have been developed to facilitate immediate results with the potential to aid screening for new disease and enable patients to self-monitor their disease. Non-communicable diseases (NCDs) are the major cause of mortality globally and are increasing in prevalence as the population ages. Allied health care professionals (AHPs) are skilled in undertaking risk assessment and delivering preventative advice, providing opportunities to access large proportions of the population who may not visit their doctor, within non-traditional community settings. There is evidence of high levels of support from public, patients and health professionals for engaging AHPs in risk-targeted early case detection of certain NCDs. Thus, POCT devices offer a potential alternative to traditional venous blood collection, as novel care pathways for increasing early case detection and access to preventative care. The objectives of this study were to: (i) determine the concordance of the specific POCT devices with laboratory-based standard assays employed within clinical biochemistry laboratories. (ii) compare the sampling experience of both methods via patient-reported experiences. METHODS: A prospective, two-centre study was undertaken involving 158 participants who provided informed consent. Venous blood was collected for traditional assays of HbA1c, creatinine/ estimated Glomerular-Filtration-Rate (eGFR) and vitamin-D. Capillary blood was collected by finger prick test and also assayed for the same biochemical indices (Nova StatSensor (creatinine/eGFR); Siemens DCA-Vantage (HbA1C); CityAssays (vitamin-D)). All users were provided with device training. Participants reported any discomfort experienced by each simultaneously applied method (randomised in order) via a 100 mm Visual-Analogue-Scale. RESULTS: Results for each POCT device and the laboratory standard were analysed by Bland-Altman plots to determine assay concordance. POCT devices demonstrated good concordance with laboratory testing, with at least 95% of all samples being within two standard deviations, for each of the devices tested. The majority of participants reported less discomfort with POCT than venepuncture, with the average reported discomfort being 17/100 mm less for POCT compared to venous blood sample collection on the visual analogue scale. CONCLUSIONS: The POCT devices demonstrated acceptable concordance with laboratory-based assays, and patients reported lower levels of discomfort compared to traditional means of blood collection. This study demonstrates the potential of using these devices as acceptable methods for opportunistic testing of "at-risk" individuals within non-traditional community care settings.

COVID-19: Seroprevalence and Vaccine Responses in UK Dental Care Professionals.

Dental care professionals (DCPs) are thought to be at enhanced risk of occupational exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, robust data to support this from large-scale seroepidemiological studies are lacking. We report a longitudinal seroprevalence analysis of antibodies to SARS-CoV-2 spike glycoprotein, with baseline sampling prior to large-scale practice reopening in July 2020 and follow-up postimplementation of new public health guidance on infection prevention control (IPC) and enhanced personal protective equipment (PPE). In total, 1,507 West Midlands DCPs were recruited into this study in June 2020. Baseline seroprevalence was determined using a combined IgGAM enzyme-linked immunosorbent assay and the cohort followed longitudinally for 6 mo until January/February 2021 through the second wave of the coronavirus disease 2019 pandemic in the United Kingdom and vaccination commencement. Baseline seroprevalence was 16.3%, compared to estimates in the regional population of 6% to 7%. Seropositivity was retained in over 70% of participants at 3- and 6-mo follow-up and conferred a 75% reduced risk of infection. Nonwhite ethnicity and living in areas of greater deprivation were associated with increased baseline seroprevalence. During follow-up, no polymerase chain reaction-proven infections occurred in individuals with a baseline anti-SARS-CoV-2 IgG level greater than 147.6 IU/ml with respect to the World Health Organization international standard 20-136. After vaccination, antibody responses were more rapid and of higher magnitude in those individuals who were seropositive at baseline. Natural infection with SARS-CoV-2 prior to enhanced PPE was significantly higher in DCPs than the regional population. Natural infection leads to a serological response that remains detectable in over 70% of individuals 6 mo after initial sampling and 9 mo from the peak of the first wave of the pandemic. This response is associated with protection from future infection. Even if serological responses wane, a single dose of the Pfizer-BioNTech 162b vaccine is associated with an antibody response indicative of immunological memory.

Attitudes towards Oral Health in Patients with Rheumatoid Arthritis: A Qualitative Study Nested within a Randomized Controlled Trial.

INTRODUCTION: Patients with rheumatoid arthritis (RA) present a higher incidence and severity of periodontitis than the general population. Our study, Outcomes of Periodontal Treatment in Patients with Rheumatoid Arthritis (OPERA), was a randomized waiting-list controlled trial using mixed methods. Patients randomized to the intervention arm received intensive periodontal treatment, and those in the control arm received the same treatment with a 6-mo delay. AIM: The nested qualitative component aimed to explore patients' experiences and priorities concerning oral health and barriers and facilitators for trial participation. METHODS: Using purposive sampling until thematic saturation was reached, we conducted 21 one-to-one semistructured interviews with randomized patients in either of the 2 treatment arms as well as with patients who did not consent for trial participation. RESULTS: The patients described their experiences about RA, oral health, and study participation. Previous experiences with dental care professionals shaped patients' current perceptions about oral health and the place of oral health on their list of priorities compared with other conditions. Patients also highlighted some of the barriers and facilitators for study participation and for compliance with oral health maintenance. The patients, in the control arm, presented their views regarding the acceptable length of waiting time for the intervention. CONCLUSION: The associations between periodontal and systemic health are increasingly recognized by the literature. Our study provided an insight into RA patients' experiences and perceptions about oral health. It also highlighted some of the barriers and facilitators for participating in a periodontal interventional study for this group. We hope that our findings will support the design of larger interventional periodontal studies in patients with RA. The complex challenges faced by the burden of RA and the associated multimorbidities in this patient group might highlight opportunities to improve access to oral health services in this patient population. KNOWLEDGE TRANSFER STATEMENT: This article provided insights into the experiences and perceptions of rheumatoid arthritis patients about their oral health to improve patient participation in a definitive clinical trial.

Periodontal diagnosis in the context of the 2017 classification system of periodontal diseases and conditions: presentation of a patient with periodontitis localised to the molar teeth.

The objective of this case report is to illustrate the diagnosis and classification of periodontitis, according to the 2017 classification system, as recommended in the British Society of Periodontology (BSP) implementation plan. A 37-year-old female was diagnosed with periodontitis (molar-incisor pattern), stage III, grade C, currently unstable. Several issues pertinent to the diagnosis of localised forms of periodontitis in young patients are discussed in relation to the current and previous classification systems. Periodontitis can be limited to a few sites and this case highlights the importance of the careful application of the basic periodontal examination (BPE).

Periodontal diagnosis in the context of the 2017 classification system of periodontal diseases and conditions - implementation in clinical practice.

The 2017 World Workshop Classification system for periodontal and peri-implant diseases and conditions was developed in order to accommodate advances in knowledge derived from both biological and clinical research, that have emerged since the 1999 International Classification of Periodontal Diseases. Importantly, it defines clinical health for the first time, and distinguishes an intact and a reduced periodontium throughout. The term 'aggressive periodontitis' was removed, creating a staging and grading system for periodontitis that is based primarily upon attachment and bone loss and classifies the disease into four stages based on severity (I, II, III or IV) and three grades based on disease susceptibility (A, B or C). The British Society of Periodontology (BSP) convened an implementation group to develop guidance on how the new classification system should be implemented in clinical practice. A particular focus was to describe how the new classification system integrates with established diagnostic parameters and pathways, such as the basic periodontal examination (BPE). This implementation plan focuses on clinical practice; for research, readers are advised to follow the international classification system. In this paper we describe a diagnostic pathway for plaque-induced periodontal diseases that is consistent with established guidance and accommodates the novel 2017 classification system, as recommended by the BSP implementation group. Subsequent case reports will provide examples of the application of this guidance in clinical practice.

Periodontal diagnosis in the context of the BSP implementation plan for the 2017 classification system of periodontal diseases and conditions: presentation of a pair of young siblings with periodontitis.

The objective of this case report is to illustrate the diagnosis and classification of periodontitis according to the 2017 classification system as recommended in the British Society of Periodontology (BSP) implementation plan. We describe two cases in the form of a pair of siblings, who developed periodontitis very early in life. A 19-year-old female was diagnosed with 'generalised periodontitis; stage III/grade C; currently unstable'. Her 14-year-old sister was diagnosed with 'localised periodontitis; stage II, grade C; currently unstable'. The present case report presents an example for the application of the new classification system and illustrates the importance of a periodontal check for children and adolescents and/or their relatives.

Periodontal diagnosis in the context of the 2017 classification system of periodontal diseases and conditions: Presentation of a middle-aged patient with localised periodontitis.

The objective of this case report is to illustrate the diagnosis and classification of periodontitis according to the 2017 classification system as recommended in the British Society of Periodontology (BSP) implementation plan. We describe a case of a patient who was diagnosed with 'localised periodontitis; stage II, grade B; currently unstable'. The present case report presents an example for the application of the new classification system and illustrates how the new classification system captures disease severity, extent and disease susceptibility by staging and grading periodontitis.

A randomised clinical study comparing the effect of Steareth 30 and SLS containing toothpastes on oral epithelial integrity (desquamation).

OBJECTIVE: To compare the clinical effect of toothpastes containing Steareth 30 and SLS (sodium lauryl sulphate) surfactants on oral epithelial integrity (desquamation) using a new Oral Mucosal Sloughing Index (OMSI). METHODS: 30 volunteers participated in a single centre, double-blind, randomised, crossover clinical study. After a lead-in, subjects were allocated to the first test toothpaste, which was applied to the maxilla via a cap splint, followed by whole mouth brushing with the respective toothpaste and rinsing with the toothpaste slurry. Soft desquamation (lesion status) was assessed using a novel Oral Mucosal Sloughing Index (OMSI). Soft tissue status was measured at baseline (prior to test product use), 30 min following test product application and 4 days later following "at home" use of test toothpaste. After a wash out period, soft tissue assessment and product use were repeated for the remaining toothpaste. RESULTS: Using the OMSI, 30 min post-application, significantly fewer lesion counts (all sites) were observed for the Steareth 30 toothpaste compared to SLS toothpaste (p < 0.0001). Additionally, 30 min after toothpaste use, the average lesion severity score was significantly lower for the Steareth 30 toothpaste compared to SLS toothpaste (p < 0.0001). There were no significant differences in lesion status at baseline or following 4 days of "at home" use of the toothpastes. No product related adverse events were reported. CONCLUSION: Using an Oral Mucosal Sloughing Index for assessment, application of a toothpaste containing Steareth 30 generated significantly less transient soft tissue desquamation (fewer lesion counts and lower severity) than a toothpaste containing SLS. CLINICAL SIGNIFICANCE: Treatment with a toothpaste containing Steareth 30 surfactant generated fewer transient soft tissue lesions (lower desquamation) compared to a toothpaste containing SLS surfactant.

Cigarette smoke modifies neutrophil chemotaxis, neutrophil extracellular trap formation and inflammatory response-related gene expression.

BACKGROUND AND OBJECTIVE: Cigarette smoking is a major risk factor for periodontitis, and smoking perturbs neutrophil reactive oxygen species production. This study tested the hypothesis that cigarette smoke extract (CSE) and its components/metabolites nicotine, cotinine and thiocyanate (SCN-), may influence neutrophil functions. MATERIAL AND METHODS: Chemotaxis was assessed in neutrophils pre-treated with CSE using real-time video microscopy. Neutrophil extracellular trap (NET) release in response to CSE, nicotine, cotinine, SCN- as well as to phorbol 12-myristate-13-acetate and hypochlorous acid following pre-treatment with CSE, nicotine, cotinine or SCN- was assessed using fluorescence-based assays. The impact of CSE and SCN- treatment on neutrophil respiratory burst- and inflammation-related gene expression (NFKBIE, DNAJB1, CXCL8, NCF1, NCF2, CYBB) was determined by real-time polymerase chain reaction. RESULTS: Both CSE and SCN- pre-treatment inhibited phorbol 12-myristate-13-acetate-stimulated NET release. Additionally, SCN- inhibited hypochlorous acid-stimulated NET formation, while SCN- alone stimulated NET release. Overall, neutrophils pre-treated with CSE exhibited reduced speed, velocity and directionality relative to untreated neutrophils. Although CSE and SCN- promoted DNAJB1 expression, increased redox-related gene expression was only detected in response to SCN-. CONCLUSION: These results suggest that CSE can alter ex vivo neutrophil activation by mechanisms independent of SCN- and nicotine, and SCN- may contribute to the perturbed innate immune responses observed in smokers.

The oral microbiome - an update for oral healthcare professionals.

For millions of years, our resident microbes have coevolved and coexisted with us in a mostly harmonious symbiotic relationship. We are not distinct entities from our microbiome, but together we form a 'superorganism' or holobiont, with the microbiome playing a significant role in our physiology and health. The mouth houses the second most diverse microbial community in the body, harbouring over 700 species of bacteria that colonise the hard surfaces of teeth and the soft tissues of the oral mucosa. Through recent advances in technology, we have started to unravel the complexities of the oral microbiome and gained new insights into its role during both health and disease. Perturbations of the oral microbiome through modern-day lifestyles can have detrimental consequences for our general and oral health. In dysbiosis, the finely-tuned equilibrium of the oral ecosystem is disrupted, allowing disease-promoting bacteria to manifest and cause conditions such as caries, gingivitis and periodontitis. For practitioners and patients alike, promoting a balanced microbiome is therefore important to effectively maintain or restore oral health. This article aims to give an update on our current knowledge of the oral microbiome in health and disease and to discuss implications for modern-day oral healthcare.

Birmingham's new dental school and hospital - A real Peter Pan of dentistry.

A look at the history of Birmingham Dental Hospital which, since it was first founded in 1858 as Birmingham Dental Dispensary, has moved six times, the sixth move being to its new Pebble Mill site on 1 April 2016.

Neutrophil Extracellular Traps in Periodontitis: A Web of Intrigue.

Neutrophil extracellular traps (NETs) represent a novel paradigm in neutrophil-mediated immunity. NETs are believed to constitute a highly conserved antimicrobial strategy comprising decondensed nuclear DNA and associated histones that are extruded into the extracellular space. Associated with the web-like strands of DNA is an array of antimicrobial peptides (AMPs), which facilitate the extracellular destruction of microorganisms that become entrapped within the NETs. NETs can be released by cells that remain viable or following a unique form of programmed cell death known as NETosis, which is dependent on the production of reactive oxygen species (ROS) and the decondensing of the nuclear DNA catalyzed by peptidyl arginine deiminase-4. NETs are produced in response to a range of pathogens, including bacteria, viruses, fungi, and protozoa, as well as host-derived mediators. NET release is, however, not without cost, as the concomitant release of cytotoxic molecules can also cause host tissue damage. This is evidenced by a number of immune-mediated diseases, in which excess or dysfunctional NET production, bacterial NET evasion, and decreased NET removal are associated with disease pathogenesis. Periodontitis is the most prevalent infectious-inflammatory disease of humans, characterized by a dysregulated neutrophilic response to specific bacterial species within the subgingival plaque biofilm. Neutrophils are the predominant inflammatory cell involved in periodontitis and have previously been found to exhibit hyperactivity and hyperreactivity in terms of ROS production in chronic periodontitis patients. However, the contribution of ROS-dependent NET formation to periodontal health or disease remains unclear. In this focused review, we discuss the mechanisms, stimuli, and requirements for NET production; the ability of NET-DNA and NET-associated AMPs to entrap and kill pathogens; and the potential immunogenicity of NETs in disease. We also speculate on the potential role of NETs in the pathogenesis of periodontitis.

Manifesto for a paradigm shift: periodontal health for a better life.

This article outlines the European Federation of Periodontology's (EFP) manifesto Periodontal Health for a Better Life which was informed by the first joint EFP/American Academy of Periodontology workshop on periodontitis and systemic health. The EFP manifesto calls upon the dental profession to engage in screening and providing preventive advice to patients who are at risk of common chronic diseases and conditions such as cardiovascular disease, diabetes and cancer. In particular, the article emphasises the dental team's role in promoting behaviour change in their patients aimed at reducing smoking and obesity levels, by promoting healthy nutrition and exercise. The chairman of the National Association of Primary Care Medicine, Dr Charles Alessi, has strongly endorsed this model and highlighted the important opportunities offered by a capitation-based new contract for the dental team to engage fully in preventive medicine in support of medical colleagues and in the best interests of public health and patients across England.

Practitioner evaluation of a novel online integrated oral health and risk assessment tool: a practice pilot.

AIM: To report the development and evaluation of an evidence-based, online, patient assessment tool, capable of measuring oral health status, future disease risk and capitation fee guidance. METHODS: An online integrated oral health and risk assessment tool called DEPPA was developed, incorporating 1) PreViser(™) risk scores for periodontal disease, caries, non-carious tooth surface loss and oral cancer, 2) revised versions of Denplan Excel's Oral Health Score and 3) capitation fee guidance score. DEPPA was piloted by 25 dentists who provided quantitative and qualitative feedback. RESULTS: Six hundred and forty assessments were performed. There was strong agreement on the need for such a tool, that it constituted a comprehensive assessment and supported good patient communication. The validity of the system was perceived as sound and the revised capitation fee guidance broadly welcomed. While some deemed the caries risk scoring algorithm to be too sensitive, the 30% high/very high risk rating is consistent with current rates of active caries in UK adults. CONCLUSIONS: A viable online oral health and risk-assessment tool has been developed (DEPPA) that will allow dental teams to measure oral health status, future disease risk and receive ongoing guidance on capitation fee setting. The indications are that DEPPA could be a valuable audit, care planning and patient communication tool.

Late diagnosis of an occult tumour - what lessons can we learn?

OBJECTIVE: Malignant tumours of the nasal cavity and paranasal sinuses are rare and late presentation of a maxillary sinus tumour is common due to the vague nature of the symptoms which can delay diagnosis. METHODS: We report a female with a maxillary sinus tumour who was initially diagnosed with chronic idiopathic facial pain (CIFP) and sinusitis, which subsequently led to a delay in diagnosis and treatment of her tumour. RESULTS: There was no clinical extra- or intra-oral pathology, however, she had varying clinical presentations of facial pain, anosmia, loss of gustatory function, and infra-orbital nerve paraesthesia. CT and MRI scans confirmed obliteration of the left maxillary sinus by a solid mass involving ethmoid and sphenoid sinuses and some cranial nerves. Biopsy confirmed a poorly differentiated carcinoma of the ethmoid and sphenoid sinuses and invasion of the cavernous sinus. CONCLUSION: A morbid, but hidden tumour was left undiagnosed due to the unusual presentation of the patient's symptoms. It is essential that all patients are managed holistically and thorough historical, clinical and radiographic examination and appropriate investigations are carried out to prevent unnecessary and potentially time-wasting treatment.

Hypochlorous acid regulates neutrophil extracellular trap release in humans.

Neutrophil extracellular traps (NETs) comprise extracellular chromatin and granule protein complexes that immobilize and kill bacteria. NET release represents a recently discovered, novel anti-microbial strategy regulated non-exclusively by nicotinamide adenine dinucleotide phosphate (NADPH) oxidase generation of reactive oxygen intermediates (ROIs), particularly hydrogen peroxide. This study aimed to characterize the role of ROIs in the process of NET release and to identify the dominant ROI trigger. We employed various enzymes, inhibitors and ROIs to record their effect fluorometrically on in vitro NET release by human peripheral blood neutrophils. Treatment with exogenous superoxide dismutase (SOD) supported the established link between hydrogen peroxide and NET production. However, treatment with myeloperoxidase inhibitors and direct addition of hypochlorous acid (HOCl; generated in situ from sodium hypochlorite) established that HOCl was a necessary and sufficient ROI for NET release. This was confirmed by the ability of HOCl to stimulate NET release in chronic granulomatous disease (CGD) patient neutrophils which, due to the lack of a functional NADPH oxidase, also lack the capacity for NET release in response to classical stimuli. Moreover, the exogenous addition of taurine, abundantly present within the neutrophil cytosol, abrogated NET production stimulated by phorbol myristate acetate (PMA) and HOCl, providing a novel mode of cytoprotection by taurine against oxidative stress by taurine.

Extracellular deoxyribonuclease production by periodontal bacteria.

BACKGROUND AND OBJECTIVE: Whilst certain bacteria have long been known to secrete extracellular deoxyribonuclease (DNase), the purpose in microbial physiology was unclear. Recently, however, this enzyme has been demonstrated to confer enhanced virulence, enabling bacteria to evade the host's immune defence of extruded DNA/chromatin filaments, termed neutrophil extracellular traps (NETs). As NETs have recently been identified in infected periodontal tissue, the aim of this study was to screen periodontal bacteria for extracellular DNase activity. MATERIAL AND METHODS: To determine whether DNase activity was membrane bound or secreted, 34 periodontal bacteria were cultured in broth and on agar plates. Pelleted bacteria and supernatants from broth cultures were analysed for their ability to degrade DNA, with relative activity levels determined using an agarose gel electrophoresis assay. Following culture on DNA-supplemented agar, expression was determined by the presence of a zone of hydrolysis and DNase activity related to colony size. RESULTS: Twenty-seven bacteria, including red and orange complex members Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium nucleatum, Parvimonas micra, Prevotella intermedia, Streptococcus constellatus, Campylobacter rectus and Prevotella nigrescens, were observed to express extracellular DNase activity. Differences in DNase activity were noted, however, when bacteria were assayed in different culture states. Analysis of the activity of secreted DNase from bacterial broth cultures confirmed their ability to degrade NETs. CONCLUSION: The present study demonstrates, for the first time, that DNase activity is a relatively common property of bacteria associated with advanced periodontal disease. Further work is required to determine the importance of this bacterial DNase activity in the pathogenesis of periodontitis.