An update on the evidence for pathogenic mechanisms that may link periodontitis and diabetes

The association of periodontal disease with the complications of diabetes mellitus. A systematic review

This review investigated the association of periodontal disease with diabetes mellitus (DM) and diabetic complications. PubMed/MEDLINE was searched including search terms "periodontal" OR "periodontitis" AND "diabetic complications" OR "diabetic retinopathy" OR "diabetic nephropathy" OR "diabetic neuropathy" OR "cardiovascular disease diabetes" OR "myocardial infarction diabetes" OR "cerebrovascular disease diabetes" OR "stroke diabetes" OR "peripheral vascular disease diabetes". Fourteen studies included in this review consistently reported an increased risk for diabetic complications including microvascular, macrovascular and death in the presence of periodontal disease. Higher risks for diabetic retinopathy (odds ratios: 2.8-8.7), neuropathy (3.2-6.6), nephropathy (1.9-8.5), cardiovascular complications (1.28-17.7) and mortality (2.3-8.5) were reported for people with diabetes with periodontitis compared to those with diabetes who have no periodontitis. This novel review summarizes current data providing further evidence of a link between poor oral health and DM and its complications. It has also drawn attention to major limitations of the available data linking periodontal disease and diabetic complications.

Association between periodontitis and pulmonary function based on the Third National Health and Nutrition Examination Survey (NHANES III)

OBJECTIVES

The purpose of this study was to investigate the association between impaired pulmonary function and periodontitis.

MATERIALS AND METHODS

From the Third National Health and Nutrition Examination Survey data, we examined the association between pulmonary function and severity of periodontitis using the univariate and multivariate regression models. Moreover, the association between obstructive or restrictive spirometry patterns and periodontitis status was also determined by multivariable logistic regression analysis.

RESULTS

A total of 10,645 participants were included in our study. The values of predicted FEV1%, predicted FVC%, and FEV1/FVC were found to gradually decline with increasing severity of periodontitis (p < .001). Obstructive and restrictive pulmonary functions were significantly associated with severity of periodontitis.

CONCLUSION

Individuals with a greater degree of periodontitis had poor pulmonary function. However, further long-term cohort studies are required for a comprehensive evaluation.

Porphyromonas gingivalis Inhibition of MicroRNA-205-5p Expression Modulates Proinflammatory Cytokines in Gingival Epithelial Cells

In this study, we strived to investigate the effect of miR-205-5p on JAK/STAT signaling way induced by P. gingivalis in periodontitis. Microarray analysis was conducted to find differentially expressed miRNAs in periodontitis patients. The miRNAs related to JAK/STAT signaling way were selected via DIANA TOOLS, and the targeted mRNAs of miRNAs were predicted by TargetScan. The expression of miRNAs and mRNAs, differentially expressed in periodontitis and related to JAK/STAT signaling, was detected by qRT-PCR or western blot. The relationship between miRNAs and mRNAs was confirmed by a dual luciferase assay. MiR-205-5p was downregulated and IL6ST was upregulated in periodontitis patients' clinical samples. MiR-205-5p had target binding sites of IL6ST 3' untranslated region. QRT-PCR and western blot analysis demonstrated poor expression of miR-205-5p, while IL6ST, pJAK2, p-STAT3 were extremely upregulated in gingival epithelial cells (GECs) with P. gingivalis induction. IL6ST expression in periodontitis tissue was also increased. P. gingivalis could inhibit miR-205-5p expression to activate JAK/STAT signaling in GECs and promote the occurrence and development of periodontitis.

The impact of diabetes on periodontal diseases

The susceptibility and severity of periodontal diseases is made more severe by diabetes, with the impact on the disease process inversely proportional to the level of glycemic control. Although type 1 diabetes mellitus and type 2 diabetes mellitus have different etiologies, and their impact on bone is not identical, they share many of the same complications. Studies in animals and humans agree that both forms of diabetes increase inflammatory events in periodontal tissue, impair new bone formation, and increase expression of RANKL in response to bacterial challenge. High levels of glucose, reactive oxygen species, and advanced glycation end-products are found in the periodontium of diabetic individuals and lead to increased activation of nuclear factor-kappa B and expression of inflammatory cytokines such as tumor necrosis factor and interleukin-1. Studies in animals, moreover, suggest that there are multiple cell types in periodontal tissues that are affected by diabetes, including leukocytes, vascular cells, mesenchymal stem cells, periodontal ligament fibroblasts, osteoblasts, and osteocytes. The etiology of periodontal disease involves the host response to bacterial challenge that is affected by diabetes, which increases the expression of RANKL and reduces coupled bone formation. In addition, the inflammatory response also modifies the oral microbiota to render it more pathogenic, as demonstrated by increased inflammation and bone loss in animals where bacteria are transferred from diabetic donors to germ-free hosts compared with transfer from normoglycemic donors. This approach has the advantage of not relying upon limited knowledge of the specific bacterial taxa to determine pathogenicity, and examines the overall impact of the microbiota rather than the presumed pathogenicity of a few bacterial groups. Thus, animal studies have provided new insights into pathogenic mechanisms that identify cause-and-effect relationships that are difficult to perform in human studies.

Association between Fatty Liver Index and Periodontitis: the Korea National Health and Nutrition Examination Survey

It has been suggested that periodontitis is associated with metabolic abnormalities including non-alcoholic fatty liver disease (NAFLD). The fatty liver index (FLI) is a non-invasive surrogate marker and predictor of NAFLD. We aimed to determine whether FLI itself would be associated with periodontitis through a secondary analysis of previously reported nationally representative probability sample data of the Korean population. FLI was calculated from a previously developed algorithm which combines measures of body mass index (BMI), waist circumference, triglyceride, and gamma-glutamyl transferase (GGT). Periodontitis was diagnosed based on the Community Periodontal Index (CPI) developed by the World Health Organization. Of 4,272 participants, 26.1% were diagnosed with periodontitis. Higher FLI was associated with a higher prevalence of periodontitis (Odds ratio (OR) _{highest vs. lowest quartile of FLI},1.63; 95% confidence interval (CI), 1.23–2.16; P = 0.001 for trend) adjusting for confounding factors. In the highest FLI quartile, prevalence of periodontitis was higher in individuals with diabetes (OR _{highest vs. lowest quartile of FLI}, 2.89; 95% CI, 1.01–8.27 for diabetic subgroup; OR _{highest vs. lowest quartile of FLI}, 1.45; 95% CI, 1.07–1.96 for non-diabetic subgroup). In summary, FLI was associated with prevalent periodontitis.

Awareness, practices, training, and confidence of Paediatric Diabetes Care Teams in relation to periodontitis

Diabetes and periodontal disease are non-communicable chronic diseases that have a bi-directional relationship. The European Federation of Periodontology and International Diabetes Federation recommend patients with diabetes should be screened for periodontal disease and referred to a dental professional where appropriate. This study investigated the awareness among Paediatric Diabetes Care Teams across England and Wales of diabetes as a risk factor for periodontal disease. The study enquired to the practices, training, and confidence of health care professionals in relation to periodontal disease. A semi-structured online questionnaire was sent to all health care professionals working within Paediatric Diabetes Care Teams across England and Wales. Findings showed that 76.2% of participants were aware that periodontitis is a possible complication of diabetes. Only 5.2% screened for periodontal issues, while 27% of respondents stated that oral advice is not typically given to patients at their clinics and 92.3% said that there is no access to a periodontal service within their clinics. There were 76.4% participants who stated that patients are rarely or never referred to an external dental service for their periodontal health. Only 4.8% of respondents said they have received training for recognizing patients who require dental care for their periodontal health, while 23.2% feel confident identifying children who require referral and 85.4% of participants feel they would benefit from further training in periodontal health. In conclusion, patients are not routinely being informed of the risk of periodontitis or being screened or referred for it. Further training would be perceived as beneficial.

Accelerated degradation of collagen membranes in type 1 diabetic rats is associated with increased expression and production of several inflammatory molecules

BACKGROUND

Membrane durability is critical for regenerative procedures. We reported previously that type 1-like diabetes in rats accelerates the degradation of collagen membranes and we tested here whether this is associated with increased local production of inflammatory molecules as part of a diabetes-induced chronic inflammation around and within the membranes.

METHODS

Collagen membrane discs were implanted under the scalp in diabetic (streptozotocin-induced) and control rats, which were sacrificed after 2 or 3 weeks. Total RNA and proteins were isolated from the membrane and its surrounding tissues and the expression and production of six inflammatory molecules (interleukin-6 [IL-6], tumor necrosis factor alpha [TNFα], matrix metalloproteinase [MMP]-9, macrophage migration inhibitory factor [MIF], MIP-1α, and MIP-2α) was measured using real-time PCR and western blotting, respectively. Minimal histological analysis of the membranes was conducted to conform to previous studies.

RESULTS

Hyperglycemia resulted in reduced membrane thickness (by 10% to 25%) and increased mononuclear infiltrate inside the membrane. mRNA and protein levels of IL-6, TNFα, and MMP-9 were elevated in diabetic rats both 2 and 3 weeks post-surgery. The levels (both mRNA and protein) of MIF were increased at 2 weeks post-surgery and those of MIP-1α and MIP-2α at 3 weeks. There was a very good match in the temporal changes of all examined genes between the mRNA and protein levels.

CONCLUSIONS

Elevated local production of inflammatory cytokines and MMPs, together with apparent mononuclear infiltrate and increased collagenolysis confirm that hyperglycemia leads to a chronic inflammation in and around the implanted collagen membranes, which reduces membrane longevity.

Uptake of best practice recommendations in the management of patients with diabetes and periodontitis: a cross-sectional survey of healthcare professionals in primary care

OBJECTIVES

To investigate the practices of healthcare professionals in relation to best practice recommendations for the multidisciplinary management of people with diabetes and periodontitis, focusing on two clinical behaviours: informing patients about the links between diabetes and periodontitis, and suggesting patients with poorly controlled diabetes go for a dental check-up.

DESIGN

Cross-sectional design utilising online questionnaires to assess self-reported performance and constructs from Social Cognitive Theory (SCT) and Normalisation Process Theory.

SETTING

Primary care medical practices (n=37) in North East, North Cumbria and South West of England Clinical Research Networks.

PARTICIPANTS

96 general practitioners (GPs), 48 nurses and 21 healthcare assistants (HCAs).

RESULTS

Participants reported little to no informing patients about the links between diabetes and periodontitis or suggesting that they go for a dental check-up. Regarding future intent, both GPs (7.60±3.38) and nurses (7.94±3.69) scored significantly higher than HCAs (4.29±5.07) for SCT proximal goals (intention) in relation to informing patients about the links (p<0.01); and nurses (8.56±3.12) scored significantly higher than HCAs (5.14±5.04) for suggesting patients go for a dental check-up (p<0.001). All professional groups agreed on the potential value of both behaviours, and nurses scored significantly higher than GPs for legitimation (conforms to perception of job role) in relation to informing (nurses 4.16±0.71; GPs 3.77±0.76) and suggesting (nurses 4.13±0.66; GPs 3.75±0.83) (both p<0.01). The covariate background information (OR=2.81; p=0.03) was statistically significant for informing patients about the links.

CONCLUSIONS

Despite evidence-informed best practice recommendations, healthcare professionals currently report low levels of informing patients with diabetes about the links between diabetes and periodontitis and suggesting patients go for a dental check-up. However, healthcare professionals, particularly nurses, value these behaviours and consider them appropriate to their role. While knowledge of the evidence is important, future guidelines should consider different strategies to enable implementation of the delivery of healthcare interventions.

Integrated hypothesis of dental caries and periodontal diseases

This review considers an integrated hypothesis of dental caries and periodontal diseases that builds on theoretical ecological principles. The backbone of the hypothesis is based on the dynamic stability stage of the oral microbiota, at which intrinsic (mainly saliva and gingival crevicular fluid) and bacterial (mainly metabolic) resilience factors maintain ecological dynamic stability, compatible with clinical health. However, loss of intrinsic resilience factors and/or prolonged changes in the availability of microbial metabolic substrates may shift the ecological balance of the microbiota into either saccharolytic (acidogenic) or amino acid-degrading/proteolytic (alkalinogenic) stages, depending on the nature of the predominant substrates, leading to clinical diseases. Therefore, to maintain and restore the dynamic stability of the oral microbiota, it is necessary to control the drivers of disease, such as salivary flow and influx of bacterial nutrients into the oral cavity. Contrary to conventional wisdom, excessive intake of fermentable carbohydrates may contribute to inflammation in periodontal tissues resulting from hyperglycaemia. An integrated hypothesis emphasizes that both dental caries and periodontal diseases originate in the dynamic stability stage and emerge in response to nutritional imbalances in the microbiota. Periodontal diseases may belong to the sugar driven inflammatory diseases, similar to diabetes, obesity, and cardiovascular diseases.

The Association of Periodontal Treatment and Decreased Pneumonia: A Nationwide Population-Based Cohort Study

Pneumonia is a common respiratory infectious disease that involves the inflammation of the pulmonary parenchyma. Periodontal disease is widespread and correlated with pneumonia. However, the relationship between periodontal treatment and clinical infectious outcomes in patients with pneumonia has remained undetermined. The aim of this study was to investigate the association between periodontal treatment and the risk of pneumonia events in the Taiwanese population. A nationwide population-based cohort study was conducted using data from the Taiwanese National Health Insurance Research Database (NHIRD). A total of 49,400 chronic periodontitis patients who received periodontal treatment from 2001 to 2012 were selected. In addition, 49,400 healthy individuals without periodontal diseases were picked randomly from the general population after propensity score matching according to age, gender, monthly income, urbanization, and comorbidities. The Cox proportional hazard regression analysis was adopted to assess the hazard ratio (HR) of pneumonia between the periodontal treatment cohort and the comparison cohort. The average ages of the periodontal treatment and comparison groups were 44.25 ± 14.82 years and 44.15 ± 14.5 years, respectively. The follow up durations were 7.66 and 7.41 years for the periodontal treatment and comparison groups, respectively. We found 2504 and 1922 patients with newly diagnosed pneumonia in the comparison cohort and the periodontal treatment cohort, respectively. The Kaplan–Meier plot revealed that the cumulative incidence of pneumonia was significantly lower over the 12 year follow-up period in the periodontal treatment group (using the log-rank test, p < 0.001). In conclusion, this nationwide population-based study indicated that the patients with periodontal treatment exhibited a significantly lower risk of pneumonia than the general population.

Diabetes, Diabetic Complications, and Phosphate Toxicity: A Scoping Review

This article presents a scoping review and synthesis of research findings investigating the toxic cellular accumulation of dysregulated inorganic phosphate-phosphate toxicity-as a pathophysiological determinant of diabetes and diabetic complications. Phosphorus, an essential micronutrient, is closely linked to the cellular metabolism of glucose for energy production, and serum inorganic phosphate is often transported into cells along with glucose during insulin therapy. Mitochondrial dysfunction and apoptosis, endoplasmic reticulum stress, neuronal degeneration, and pancreatic cancer are associated with dysregulated levels of phosphate in diabetes. Ectopic calcification involving deposition of calcium-phosphate crystals is prevalent throughout diabetic complications, including vascular calcification, nephropathy, retinopathy, and bone disorders. A low-glycemic, low-phosphate dietary intervention is proposed for further investigations in the treatment and prevention of diabetes and related diabetic pathologies.

Associação entre condições sistêmicas e gravidade da doença periodontal em pacientes atendidos na Clínica-Escola da UFCG

Resumo Introdução A doença periodontal é uma doença inflamatória crônica dos tecidos de proteção e suporte dos dentes. As doenças ou alterações de ordem sistêmica, como diabetes, alterações cardiovasculares e pulmonares, distúrbios hormonais e outras, não iniciam a doença periodontal, mas podem acelerar uma doença preexistente, aumentando sua progressão e destruição tecidual. Objetivo O presente estudo teve como objetivo avaliar, por meio de prontuários clínicos, uma possível associação entre as condições sistêmicas e a gravidade da doença periodontal em pacientes atendidos na Clínica-Escola de Odontologia da Universidade Federal de Campina Grande, campus CSTR (UFCG-CSTR). Material e método Para o estudo, foram avaliados 1.035 prontuários clínicos dos pacientes que procuraram atendimento na Clínica-Escola de Odontologia da UFCG-CSTR durante os anos de 2012 a 2017. Resultado A população estudada apresentou prevalência do sexo masculino (50,9%) e diagnóstico de doença gengival (63,6%) e periodontal (35,8%). As condições sistêmicas mais prevalentes foram hipertensão (15%), diabetes (7,5%) e cardiopatias (5,8%). Além disso, 20,2% relataram ser fumantes ou ex-fumantes, enquanto o uso de medicação foi observado em 28,3% dos casos. Foi verificada associação estatisticamente significativa entre doença periodontal, sexo masculino, faixa etária mais avançada, hipertensão arterial, tabagismo ou histórico de tabagismo e diabetes. Conclusão Foi observada uma quantidade de dentes igual ou menor do que 10 com maior frequência entre os pacientes com idade igual ou superior a 60 anos, hipertensos, diabéticos, cardiopatas e fumantes ou ex-fumantes, sugerindo, desse modo, uma maior gravidade da doença periodontal nesses indivíduos.

Periodontitis and diabetes

Periodontitis and diabetes are complex chronic diseases, linked by an established bidirectional relationship. Risk for periodontitis is increased two to three times in people with diabetes compared to individuals without, and the level of glycaemic control is key in determining risk. In people who do not have diabetes, periodontitis is associated with higher glycated haemoglobin (HbA1c) and fasting blood glucose levels, and severe periodontitis is associated with increased risk of developing diabetes. In people with type 2 diabetes, periodontitis is associated with higher HbA1c levels and worse diabetes complications. Treatment of periodontitis in people with diabetes has been shown to result in improved glycaemic control, with HbA1c reductions of 3-4 mmol/mol (0.3-0.4%) in the short term (3-4 months) post-treatment. Given that treatment of periodontitis results in clinically relevant reductions in HbA1c, the dental team has an important role in the management of patients with diabetes. Improved interprofessional working in relation to diabetes and periodontitis has been advocated by professional and scientific organisations, though practical and systemic barriers make this challenging. This paper reviews current evidence linking periodontitis and diabetes, and considers the role of the dental team in the wider context of management of patients with diabetes and periodontitis.

Periodontal manifestations of systemic diseases and developmental and acquired conditions: Consensus report of workgroup 3 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions

BACKGROUND

A variety of systemic diseases and conditions can affect the course of periodontitis or have a negative impact on the periodontal attachment apparatus. Gingival recessions are highly prevalent and often associated with hypersensitivity, the development of caries and non-carious cervical lesions on the exposed root surface and impaired esthetics. Occlusal forces can result in injury of teeth and periodontal attachment apparatus. Several developmental or acquired conditions associated with teeth or prostheses may predispose to diseases of the periodontium. The aim of this working group was to review and update the 1999 classification with regard to these diseases and conditions, and to develop case definitions and diagnostic considerations.

METHODS

Discussions were informed by four reviews on 1) periodontal manifestions of systemic diseases and conditions; 2) mucogingival conditions around natural teeth; 3) traumatic occlusal forces and occlusal trauma; and 4) dental prostheses and tooth related factors. This consensus report is based on the results of these reviews and on expert opinion of the participants.

RESULTS

Key findings included the following: 1) there are mainly rare systemic conditions (such as Papillon-Lefevre Syndrome, leucocyte adhesion deficiency, and others) with a major effect on the course of periodontitis and more common conditions (such as diabetes mellitus) with variable effects, as well as conditions affecting the periodontal apparatus independently of dental plaque biofilm-induced inflammation (such as neoplastic diseases); 2) diabetes-associated periodontitis should not be regarded as a distinct diagnosis, but diabetes should be recognized as an important modifying factor and included in a clinical diagnosis of periodontitis as a descriptor; 3) likewise, tobacco smoking - now considered a dependence to nicotine and a chronic relapsing medical disorder with major adverse effects on the periodontal supporting tissues - is an important modifier to be included in a clinical diagnosis of periodontitis as a descriptor; 4) the importance of the gingival phenotype, encompassing gingival thickness and width in the context of mucogingival conditions, is recognized and a novel classification for gingival recessions is introduced; 5) there is no evidence that traumatic occlusal forces lead to periodontal attachment loss, non-carious cervical lesions, or gingival recessions; 6) traumatic occlusal forces lead to adaptive mobility in teeth with normal support, whereas they lead to progressive mobility in teeth with reduced support, usually requiring splinting; 7) the term biologic width is replaced by supracrestal tissue attachment consisting of junctional epithelium and supracrestal connective tissue; 8) infringement of restorative margins within the supracrestal connective tissue attachment is associated with inflammation and/or loss of periodontal supporting tissue. However, it is not evident whether the negative effects on the periodontium are caused by dental plaque biofilm, trauma, toxicity of dental materials or a combination of these factors; 9) tooth anatomical factors are related to dental plaque biofilm-induced gingival inflammation and loss of periodontal supporting tissues.

CONCLUSION

An updated classification of the periodontal manifestations and conditions affecting the course of periodontitis and the periodontal attachment apparatus, as well as of developmental and acquired conditions, is introduced. Case definitions and diagnostic considerations are also presented.

Updates from the Evidence Base Examining Association between Periodontal Disease and Type 2 Diabetes Mellitus: Current Status and Clinical Relevance

PURPOSE OF THE REVIEW

Epidemiological surveillance documents an escalating epidemic prevalence of both type 2 diabetes (T2DM) and periodontal disease (PD). The principal goals of this review are to: 1) re-examine the clinical significance of associations between PD and T2DM, based on strength of collective evidence as determined by systematic review and meta-analysis, and 2) review findings of the systematic reviews and meta-analyses in light of the current understanding of PD-associated pathophysiology and intersection with T2DM pathophysiology.

RECENT FINDINGS

Tooth loss predicts risk for chronic disease and mortality. PD is significantly associated with complications of diabetes, including retinopathy. Based on systematic reviews and meta-analyses, the adjunctive use of certain antibiotics enhances non-surgical periodontal treatment (NSPT) in patients with T2DM. Systematic reviews and meta-analyses support NSPT efficacy in achieving metabolic control. Systematic reviews and meta-analyses support the association between PD and T2DM, albeit the effect size may be modest. PD-T2DM interactions have important clinical implications.

The cytokine network involved in the host immune response to periodontitis

Periodontitis is an inflammatory disease involving the destruction of both soft and hard tissue in the periodontal region. Although dysbiosis of the local microbial community initiates local inflammation, over-activation of the host immune response directly activates osteoclastic activity and alveolar bone loss. Many studies have reported on the cytokine network involved in periodontitis and its crucial and pleiotropic effect on the recruitment of specific immunocytes, control of pathobionts and induction or suppression of osteoclastic activity. Nonetheless, particularities in the stimulation of pathogens in the oral cavity that lead to the specific and complex periodontal cytokine network are far from clarified. Thus, in this review, we begin with an up-to-date aetiological hypothesis of periodontal disease and summarize the roles of cytokines in the host immune response. In addition, we also summarize the latest cytokine-related therapeutic measures for periodontal disease.

The effect of periodontal and prosthodontic therapy on glycemic control in patients with diabetes

PURPOSE

To evaluate the effect of periodontal and prosthodontic therapy on glycated hemoglobin A(HbA1c) level in patients with diabetes.

MATERIALS AND METHODS

This is a retrospective study of 70 patients suffering from diabetes who visited the Kyungpook National University Hospital between January 2016 and May 2018. Patients underwent medical evaluation for their routine check-up, which includes laboratory test for HbA1c levels. Among the 70 patients, 35 patients also visited Kyungpook National University Dental Hospital during the same period to receive periodontal and prosthodontic therapy, while the other 35 patients did not receive such therapy. The HbA1c levels were compared before and after periodontal and prosthodontic therapy. Comparisons between groups and within groups were performed using independent t-test.

RESULTS

The HbA1c levels in the group who have received periodontal and prosthodontic therapy decreased from 7.2 to 6.7 (P=.001). The HbA1c levels in the control group decreased from 7.2 to 7.1 (P=.580). The difference in changes between the two patient groups was statistically significant (P=.011).

CONCLUSION

Periodontal and prosthodontic therapy can be effective on glycemic control in patients with diabetes.

Manifestations of systemic diseases and conditions that affect the periodontal attachment apparatus: Case definitions and diagnostic considerations

OBJECTIVES

This review proposes case definitions and diagnostic considerations of systemic disorders and conditions that affect the periodontal attachment apparatus.

IMPORTANCE

Periodontal diseases and certain systemic disorders share similar genetic and/or environmental etiological factors, and affected patients may show manifestations of both diseases. Characterizing these diseases and the nature of the association between them could have important diagnostic value and therapeutic implications for patients.

FINDINGS

Numerous systemic disorders and certain medications can affect the periodontal attachment apparatus and cause loss of periodontal attachment and alveolar bone. Although many of these disorders are rare or uncommon, they often cause significant loss of periodontal tissue by influencing periodontal inflammation or through mechanisms distinct from periodontitis. Most of these disorders are due to innate mechanisms and some are acquired via environmental factors or lifestyle. Several disorders affect periodontal inflammation through alterations in the host immune response to periodontal infection; others cause defects in the gingiva or periodontal connective tissue, instigate metabolic changes in the host that affect various tissues of the periodontal apparatus, or operate by other mechanisms. For some systemic disorders that are more common, their contribution to the loss of periodontal tissue is modest, while for others, contribution is not supported by clear evidence. Few systemic medications are associated with increased loss of periodontal tissue, and these are typically medications used in the treatment of malignancies.

CONCLUSIONS

This review identifies systemic diseases and conditions that can affect the periodontal attachment apparatus and cause loss of periodontal supporting tissues and, where possible, presents case definitions for these. Many of these diseases are associated with a profound loss of periodontal attachment and alveolar bone, and for some of these disorders the periodontal manifestations may be among the first signs of the disease. These case definitions may be useful in the early diagnosis of these diseases and may contribute to an improvement in the management of periodontal manifestations and improve the quality of life for these patients.

Periodontal manifestations of systemic diseases and developmental and acquired conditions: Consensus report of workgroup 3 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions

BACKGROUND

A variety of systemic diseases and conditions can affect the course of periodontitis or have a negative impact on the periodontal attachment apparatus. Gingival recessions are highly prevalent and often associated with hypersensitivity, the development of caries and non-carious cervical lesions on the exposed root surface and impaired esthetics. Occlusal forces can result in injury of teeth and periodontal attachment apparatus. Several developmental or acquired conditions associated with teeth or prostheses may predispose to diseases of the periodontium. The aim of this working group was to review and update the 1999 classification with regard to these diseases and conditions, and to develop case definitions and diagnostic considerations.

METHODS

Discussions were informed by four reviews on 1) periodontal manifestions of systemic diseases and conditions; 2) mucogingival conditions around natural teeth; 3) traumatic occlusal forces and occlusal trauma; and 4) dental prostheses and tooth related factors. This consensus report is based on the results of these reviews and on expert opinion of the participants.

RESULTS

Key findings included the following: 1) there are mainly rare systemic conditions (such as Papillon-Lefevre Syndrome, leucocyte adhesion deficiency, and others) with a major effect on the course of periodontitis and more common conditions (such as diabetes mellitus) with variable effects, as well as conditions affecting the periodontal apparatus independently of dental plaque biofilm-induced inflammation (such as neoplastic diseases); 2) diabetes-associated periodontitis should not be regarded as a distinct diagnosis, but diabetes should be recognized as an important modifying factor and included in a clinical diagnosis of periodontitis as a descriptor; 3) likewise, tobacco smoking - now considered a dependence to nicotine and a chronic relapsing medical disorder with major adverse effects on the periodontal supporting tissues - is an important modifier to be included in a clinical diagnosis of periodontitis as a descriptor; 4) the importance of the gingival phenotype, encompassing gingival thickness and width in the context of mucogingival conditions, is recognized and a novel classification for gingival recessions is introduced; 5) there is no evidence that traumatic occlusal forces lead to periodontal attachment loss, non-carious cervical lesions, or gingival recessions; 6) traumatic occlusal forces lead to adaptive mobility in teeth with normal support, whereas they lead to progressive mobility in teeth with reduced support, usually requiring splinting; 7) the term biologic width is replaced by supracrestal tissue attachment consisting of junctional epithelium and supracrestal connective tissue; 8) infringement of restorative margins within the supracrestal connective tissue attachment is associated with inflammation and/or loss of periodontal supporting tissue. However, it is not evident whether the negative effects on the periodontium are caused by dental plaque biofilm, trauma, toxicity of dental materials or a combination of these factors; 9) tooth anatomical factors are related to dental plaque biofilm-induced gingival inflammation and loss of periodontal supporting tissues.

CONCLUSION

An updated classification of the periodontal manifestations and conditions affecting the course of periodontitis and the periodontal attachment apparatus, as well as of developmental and acquired conditions, is introduced. Case definitions and diagnostic considerations are also presented.

[Potential application of human microbiomes in the diagnosis and treatment of type 2 diabetes mellitus]

Human microbiome refers to the total microorganism genetic information of human body surface and internal, which is closely related to human health and disease. Oral and gut microbiomes are the most diverse microbial communities, which can interact and play a role in the development of the disease, and can reflect the health and disease state in real time. Type 2 diabetes mellitus is a metabolic disorder caused by both genetic and environmental factors. Recent research has shown a link between microbes and diabetes. This article reviewed the latest research on the changes of oral and gut microbiomes in type 2 diabetes mellitus patients, which expects to provide a reference for exploring the development of the disease model for prediction, diagnosis and prognosis of type 2 diabetes mellitus based on human microbiome characteristics.

Periodontal disease, smoking, cardiovascular complications and mortality in type 1 diabetes

AIM

To assess the role of periodontal disease (PD) as a predictor of coronary artery disease (CAD) and mortality in a prospective type 1 diabetes (T1D) cohort and to evaluate the role of smoking in this relationship.

METHODS

Data were based on 320 participants of the Pittsburgh Epidemiology of Diabetes Complications study of T1D who, during 1992-94, received a partial mouth periodontal exam, and who were followed for up to 19 years to ascertain complication incidence. PD was defined as clinical attachment loss of ≥4 mm for at least 10% of the examined sites. Predictors of all-cause mortality; Hard CAD (CAD death, myocardial infarction or revascularization), and Total CAD (Hard CAD, angina, ischemic ECG) were assessed using Cox models.

RESULTS

During 19 years of follow-up, 33.7% (97/288) developed CAD, 27.3% (83/304) developed Hard CAD, and 16.9% (54/320) died. Among current smokers, 46.4% (26/56) developed CAD, 42.7% (24/56) developed Hard CAD and 29.5% (18/61) died. PD was not associated with all-cause mortality, although it was a significant predictor of both CAD (HR = 1.12, CI = 1.01-1.23) and Hard CAD (HR = 1.30, CI = 1.11-1.51). As smoking modified the PD-CAD and PD-Hard CAD associations, analyses were stratified by smoking status. PD was associated with an increased risk of CAD (HR = 1.25, CI = 1.03-1.50) and Hard CAD (HR = 1.85, CI = 1.17-2.93) only among smokers.

CONCLUSION

PD was a significant predictor of CAD and Hard CAD among current smokers with T1D.

Subgingival Microbiota of Mexicans with Type 2 Diabetes with Different Periodontal and Metabolic Conditions

BACKGROUND

Type-2-Diabetes (T2D) and Periodontitis are major inflammatory diseases. However, not much is known about the specific subgingival microbiota in Mexicans with diabetes and metabolic dysbiosis. The aim of this study was to describe the subgingival microbiota of Mexicans with T2D and the different periodontal and metabolic conditions, through "Checkerboard" DNA-DNA hybridization.

METHODS

Subjects were divided into two groups-periodontal-health (PH) (PH_non-T2D; n = 59, PH_T2D; n = 14) and generalized-periodontitis (GP) (GP_non-T2D; n = 67, GP_T2D; n = 38). Obesity (BMI ≥ 30 kg/m2) and serum levels of glycated-hemoglobin (HbA1c), total-lipids, triglycerides, total-cholesterol, high-density-lipids, and low-density-lipids were measured for the T2D individuals. Subgingival microbial identification was processed for 40 species through DNA-probes.

RESULTS

Subjects with T2D harbored significantly higher mean total levels (PH: p < 0.001, and GP_NS), a lower proportion of "red" complex (GP: p < 0.01), a higher proportion of "yellow" (GP; p < 0.001), and "orange" (GP; p < 0.01) complex than the non-T2D. GP_T2D individuals exhibited a greater proportion of putative-species-Campylobacter gracilis and S. constellatus (p < 0.001), and Parvimonas micra and Prevotella nigrescens (p < 0.01), than GP_non-T2D. T2D individuals with HbA1c > 8% had presented significantly higher mean pocket-depth and higher levels of G. morbillorum (p < 0.05) and those with obesity or dyslipidemia harbored higher levels, prevalence, or proportion of Streptococcus sp., Actinomyces sp., and Capnocytophaga sp.

CONCLUSIONS

T2D individuals harbored a particular microbial profile different to non-T2D microbiota. Metabolic control was related to dysbiosis of microbiota-HbA1c>8% related to periodontitis and obesity or dyslipidemia with the predominance of saccharolytic bacteria, irrespective of their periodontal condition.

Evaluation of the effect of a toothpaste containing Pudilan extract on inhibiting plaques and reducing chronic gingivitis: A randomized, double-blinded, parallel controlled clinical trial

ETHNOPHARMACOLOGICAL RELEVANCE

Pudilan is a famous traditional Chinese medicine compound which contains several Chinese herbal ingredients, and has been wildly used to treat a variety of inflammatory diseases in China. Recently, it was reported that Pudilan extract had been used in the oral field, especially in the treatment of minor oral ulcers for its anti-inflammatory, pain relieving, antibacterial, clearing heat, and detoxifying effects.

AIM OF THE STUDY

To evaluate the effectiveness and safety of Pudilan extract-containing toothpaste in controlling plaques and reducing chronic gingivitis.

MATERIALS AND METHODS

A total of 120 patients with chronic gingivitis were randomized into an experiment group and a control group (n = 60 patients per group) based on a double-blinded method. Patients in the experiment group used a Pudilan extract-containing toothpaste, whereas patients in the control group used a Pudilan toothpaste simulator, which were identical as the toothpaste used by the experiment group, except for not containing the Pudilan extract. The Plaque Index (PI), Gingival Index (GI), Bleeding Index (BI), and Bleeding On Probing proportion (BOP%) were recorded at baseline, 4 weeks, 8 weeks and 12 weeks after using the toothpaste.

RESULTS

After using the toothpaste for 8 and 12 weeks, PI, BI, GI, and BOP% of the experiment group were significantly lower when compared to the control group (both p < 0.001). Moreover, after using the toothpaste for 4, 8, and 12 weeks, the decline of the PI and GI in the experiment group were significantly higher than the control group (p < 0.001, except 4weeks PI p = 0.011). After 12 weeks, the PI of the experiment group decreased 35.73% (p < 0.001) whereas the GI decreased 29.04% (p < 0.001). BI and BOP decline rates were statistically significant when compared to those of the control group at 8 and 12 weeks (both p < 0.001). Moreover, at 12 weeks, the BI of the experiment group decreased 34.33% (p < 0.001) and BOP% decreased 54.71% (p < 0.001).

CONCLUSION

Toothpaste with Pudilan extract demonstrated good effect on relieving symptoms of chronic gingivitis by inhibiting plaque formation, reducing gingival inflammation and the degree of bleeding, and the bleeding rate. Toothpaste containing Pudilan extract has prospective application potentials in the prevention and treatment of chronic gingivitis.

Synergistic alveolar bone resorption by diabetic advanced glycation end products and mechanical forces

BACKGROUND

The association between diabetes mellitus (DM) and bone diseases is acknowledged. However, the mechanistic pathways leading to the alveolar bone (AB) destruction remain unclear. This study aims to elucidate the mechanical forces (MF)-induced AB destruction in DM and its underlying mechanism.

METHODS

In vivo periodontal tissue responses to MF were evaluated in rats with diabetes. In vitro human periodontal ligament (PDL) cells were either treated with advanced glycation end products (AGEs) alone or with AGEs and MF.

RESULTS

In vivo, the transcription of VEGF-A, colony stimulating factor-1 (CSF-1), and Ager was upregulated in diabetes, whereas changes in DDOST and Glo1 mRNAs were negligible. DM induced VEGF-A protein in the vascular cells of the PDL and subsequent angiogenesis, but DM itself did not induce osteoclastogenesis. MF-induced AB resorption was augmented in DM, and such augmentation was morphologically substantiated by the occasional undermining resorption as well as the frontal resorption of the AB by osteoclasts. The mRNA levels of CSF-1 and vascular endothelial growth factor (VEGF) during MF application were highly elevated in diabetes, compared with those of the normal counterparts. In vitro, AGEs treatment elevated Glut-1 and CSF-1 mRNA levels via the p38 and JNK pathways, whereas OGT and VEGF levels remained unchanged. Compressive MF especially caused upregulation of VEGF, CSF-1, and Glut-1 levels, and such upregulation was further enhanced by AGEs treatment.

CONCLUSIONS

Overloaded MF and AGEs metabolites may synergistically aggravate AB destruction by upregulating CSF-1 and VEGF. Therefore, regulating the compressive overloading of teeth, as well as the levels of diabetic AGEs, may prove to be an effective therapeutic modality for managing DM-induced AB destruction.

Undetected Dysglycemia Is an Important Risk Factor for Two Common Diseases, Myocardial Infarction and Periodontitis: A Report From the PAROKRANK Study

OBJECTIVE

Information on the relationship among dysglycemia (prediabetes or diabetes), myocardial infarction (MI), and periodontitis (PD) is limited. This study tests the hypothesis that undetected dysglycemia is associated with both conditions.

RESEARCH DESIGN AND METHODS

The PAROKRANK (Periodontitis and Its Relation to Coronary Artery Disease) study included 805 patients with a first MI and 805 matched control subjects. All participants without diabetes (91%) were examined with an oral glucose tolerance test. Abnormal glucose tolerance (AGT) (impaired glucose tolerance or diabetes) was categorized according to the World Health Organization. Periodontal status was categorized from dental X-rays as healthy (≥80% remaining alveolar bone height), moderate (79-66%), or severe (<66%) PD. Odds ratios (ORs) and 95% CIs were calculated by logistic regression and were adjusted for age, sex, smoking, education, marital status, and explored associated risks of dysglycemia to PD and MI, respectively.

RESULTS

AGT was more common in patients than in control subjects (32% vs. 19%; P < 0.001) and was associated with MI (OR 2.03; 95% CI 1.58-2.60). Undetected diabetes was associated with severe PD (2.50; 1.36-4.63) and more strongly in patients (2.35; 1.15-4.80) than in control subjects (1.80; 0.48-6.78), but not when categorized as AGT (total cohort: 1.07; 0.67-1.72). Severe PD was most frequent in subjects with undetected diabetes, and reversely undetected diabetes was most frequent in patients with severe PD.

CONCLUSIONS

In this large case-control study previously undetected dysglycemia was independently associated to both MI and severe PD. In principal, it doubled the risk of a first MI and of severe PD. This supports the hypothesis that dysglycemia drives two common diseases, MI and PD.

Increased Risk of Carotid Atherosclerosis in Male Patients with Chronic Periodontitis: A Nationwide Population-Based Retrospective Cohort Study

Carotid artery stenosis is a narrowing or constriction of any part of the carotid arteries, usually caused by atherosclerosis. However, no studies have specifically evaluated the association between carotid atherosclerosis (CA) and chronic periodontitis (CP). This study was to investigate the role of CP in increasing the subsequent risk of CA in the overall Taiwanese population. We carried out this retrospective cohort study, employing data derived from the National Health Insurance Research Database. A total of 72,630 patients who were newly diagnosed with CP from 2001 to 2012 were selected. For a propensity-matched control group, 72,630 healthy patients without CP were picked at random, matched according to age, sex, and index year from the general population. Cox proportional hazard regression analysis, which included sex, age, and comorbidities, was adopted to assess the hazard ratio (HR) of CA between the CP cohort and non-CP cohort. The average ages of the CP and non-CP groups were 44.02 ± 14.63 years and 44.15 ± 14.41 years, respectively. The follow up durations were 8.65 and 8.59 years for CP and non-CP groups, respectively. The results demonstrated that 305 and 284 patients with newly diagnosed CA were found in the CP cohort and non-CP cohort, respectively. There was no significant difference of developing CA in the CP cohort compared with the non-CP cohort (adjusted HR) 1.01, 95% confidence interval (CI, 0.86-1.19). However, multivariate Cox regression analysis indicated that the male group had significantly higher incidence risk of CA (log rank p = 0.046). In conclusion, this nationwide retrospective cohort study indicated that male patients with CP exhibited a significantly higher risk of CA than those without CP.

Aliskiren Attenuates the Inflammatory Response and Wound Healing Process in Diabetic Mice With Periodontal Disease

The aim of this study was to characterize the role of local RAS (renin–angiotensin system) in the inflammatory response of normal (N) and diabetic (D) mice with periodontal disease (PD). Diabetes Mellitus (DM) was induced by peritoneal injection of streptozotocin in Balb/c mice. PD was induced by ligature around the first molar in both N and D, irrespective of whether they were treated with aliskiren (50 mg/kg, Alisk). Mandibles were harvested for histomorphometric analyses, and gingival tissue (GT) was collected to evaluate gene expression and extracellular matrix components (ECM). Immunohistochemical (IHC) analyses were used to localize RAS in GT. The production of C-reactive protein (CRP), IL-1β, CXCL2, and CCL8 was evaluated by enzyme-linked immunosorbent assay (ELISA). Renin was found to exacerbate the inflammation and periodontal bone loss at 14 days after PD, and Alisk inhibited this process in GT of N and D. PD increased CRP, CXCL2, CCL8, and IL-1β production in both animals. Alisk could inhibit CRP, CXCL2, and CCL8 primarily in D animals. However, only CCL8 was decreased in N animals after Alisk pretreatment. PD enhanced expression and production of AGT, ACE, AT1R, and AT2R in both N and D. AT1R expression was higher in D with PD, and AT2R expression was higher in N with PD. ACE2 and receptor Mas (MasR) expression and production was elevated in the control group of both animals. PD inhibited ACE2 in N but not in D. MasR expression was unaffected in both N and D with PD. Alisk reduced expression and production of all RAS components in GT of both animals, except for ACE2 in N. RAS staining was observed in all layers of epithelium, basal cell layer, and lamina propria and was higher in N with PD. Col1a1, Col1a2, Col3a1, and fibronectin (Fn1) were increased in both animals with PD. Alisk inhibited Col1a1 and Fn in both animals, Col1a2 was decreased only in D, while levels of Col3a1 remained unchanged in all animal groups. In conclusion, these data demonstrated the presence and functional role of local RAS in GT, exacerbating the inflammatory response, periodontal bone loss, and wound healing processes in both N and D animal groups. In addition, Alisk was able to significantly reduce gingival inflammation, excessive wound healing processes, and periodontal bone loss.

Efficacy of locally-delivered statins adjunct to non-surgical periodontal therapy for chronic periodontitis: a Bayesian network analysis

BACKGROUND

Studies indicate locally-delivered statins offer additional benefits to scaling and root planning (SRP), however, it is still hard to say which type of statins is better. This network meta-analysis aimed to assess the effect of locally-delivered statins and rank the most efficacious statin for treating chronic periodontitis (CP) in combination with SRP.

METHODS

We screened four literature databases (Pubmed, Embase, Cochrane Library, and Web of Science) for randomized controlled clinical trials (RCTs) published up to June 2018 that compared different statins in the treatment of chronic periodontitis. The outcomes analyzed were changes in intrabony defect depth (IBD), pocket depth (PD), and clinical attachment level (CAL). We carried out Bayesian network meta-analysis of CP without systemic diseases. Traditional and Bayesian network meta-analyses were conducted using random-effects models.

RESULTS

Greater filling of IBD, reduction in PD, and gain in CAL were observed for SRP treated in combination with statins when compared to SRP alone for treating CP without systemic diseases. Specifically, SRP+ Atorvastatin (ATV) (mean difference [MD]: 1.5 mm, 1.4 mm, 1.8 mm, respectively), SRP + Rosuvastatin (RSV) (MD: 1.8 mm, 2.0 mm, 2.1 mm, respectively), and SRP + Simvastatin (SMV) (MD: 1.1 mm, 2.2 mm, 2.1 mm, respectively) were identified. However, no difference was found among the statins tested. In CP patients with type 2 diabetic (T2DM) or in smokers, additional benefits were observed from locally delivered statins.

CONCLUSION

Local statin use adjunctive to SRP confers additional benefits in treating CP by SRP, even in T2DM and smokers. RSV may be the best one to fill in IBD. However, considering the limitations of this study, clinicians must use cautious when applying the results and further studies are required to explore the efficacy of statins in CP with or without the risk factors (T2DM comorbidity or smoking history).

Impact of systemic diseases and tooth-based factors on outcome of root canal treatment

AIM

To investigate the impact of systemic health and tooth-based factors on the outcome of root canal treatment (RCT).

METHODOLOGY

The target population consisted of all patients receiving RCT at the Helsinki University Clinic in 2008-2011. The inclusion criteria were diagnosable pre- and postoperative (minimum 6 months after root filling) radiographs and adequate patient records of RCT available. Teeth extracted for nonendodontic reasons were excluded. Patient documents including digital radiographs of 640 permanent teeth in 504 patients were scrutinized. The radiographs were assessed by two examiners under standardized conditions. The Periapical Index was used to define radiographically 'healthy' and 'healing' cases as successful. Data included systemic health, technical quality of root fillings, type of restoration and level of alveolar bone loss. Statistical evaluation of differences between groups included chi-squared tests and Fisher's exact tests. Logistic regression modelling utilizing robust standard errors to allow for clustering within patients was applied to analyse factors related to the outcome of RCT.

RESULTS

The mean age of patients was 51.5 years (standard deviation (SD) 15.0; range 10-83), and 49% were female. In 41 cases (6%), the patient had diabetes mellitus (DM), in 132 (21%) cardiovascular disease and in 284 (44%) no systemic disease. The follow-up period was 6-71 months (mean 22.7). In the primary analyses, the success rate of RCT was 73.2% in DM patients and 85.6% in patients with no systemic disease (P = 0.043); other systemic diseases had no impact on success. In the multifactorial analysis, the impact of DM became nonsignificant and RCTs were more likely to succeed in the absence of apical periodontitis (AP; odds ratio (OR) = 4.4; P < 0.001), in teeth with optimal root filling quality (OR = 2.5; P < 0.001), in teeth restored with indirect restorations (OR = 3.7; P = 0.002) and in teeth with none/mild alveolar bone loss (OR = 2.4; P = 0.003).

CONCLUSIONS

DM diminished the success of RCT, especially in teeth with apical periodontitis. However, tooth-based factors had a more profound impact on the outcome of RCT. This should be considered in clinical decision-making and in assessment of RCT prognosis.

Increased Risk of Polycystic Ovary Syndrome in Taiwanese Women with Chronic Periodontitis: A Nationwide Population-Based Retrospective Cohort Study

Background: Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders among women of reproductive age. Both hormonal and inflammatory influences are assumed to affect periodontal tissues. Previous studies have shown that PCOS patients could have higher prevalence of gingival inflammation. However, the relationship between PCOS and chronic periodontitis (CP) is not clear. Materials and Methods: In this study, we evaluated the risk of PCOS from CP exposure in a nationwide population-based retrospective cohort study in Taiwan. We studied the claims data of Taiwanese population from 2001 to 2012. The 24,410 female patients with CP were identified from the National Health Insurance Database. The 24,410 controls were selected with randomly frequency matched by age, sex, and index year from the general population. The risk of PCOS was analyzed by Cox proportional hazards regression models, including sex, age, and comorbidities. Results: In this study, 24,410 female patients with CP (mean age: 35.14 ± 8.81 years) and 24,410 controls (mean age: 35.14 ± 8.8 years) were observed for 8.89 and 8.85 years, respectively. A total of 441 cases of PCOS were identified in CP cohort and 304 cases in non-CP cohort. Multivariate Cox regression analysis indicated that the incidence rate of PCOS was significantly higher in CP cohort than those in non-CP cohort (adjusted hazard ratio: 1.44, 95% confidence interval: 1.24-1.67). Conclusions: Taken together, this nationwide retrospective cohort study demonstrated that the risk of PCOS was significantly higher in female patients with CP than those without CP in Taiwan.

Whole metagenomic shotgun sequencing of the subgingival microbiome of diabetics and non-diabetics with different periodontal conditions

OBJECTIVE

The aim of this study was to use high-resolution whole metagenomic shotgun sequencing to characterize the subgingival microbiome of patients with/without type 2 Diabetes Mellitus and with/without periodontitis.

DESIGN

Twelve subjects, falling into one of the four study groups based on the presence/absence of poorly controlled type 2 Diabetes Mellitus and moderate-severe periodontitis, were selected. For each eligible subject, subgingival plaque samples were collected at 4 sites, all representative of the periodontal condition of the individual (i.e., non-bleeding sulci in subjects without a history of periodontitis, bleeding pockets in patients with moderate-severe periodontitis). The subgingival microbiome was evaluated using high-resolution whole metagenomic shotgun sequencing.

RESULTS

The results showed that: (i) the presence of type 2 Diabetes Mellitus and/or periodontitis were associated with a tendency of the subgingival microbiome to decrease in richness and diversity; (ii) the presence of type 2 Diabetes Mellitus was not associated with significant differences in the relative abundance of one or more species in patients either with or without periodontitis; (iii) the presence of periodontitis was associated with a significantly higher relative abundance of Anaerolineaceae bacterium oral taxon 439 in type 2 Diabetes Mellitus patients.

CONCLUSIONS

Whole metagenomic shotgun sequencing of the subgingival microbiome was extremely effective in the detection of low-abundant taxon. Our results point out a significantly higher relative abundance of Anaerolineaceae bacterium oral taxon 439 in patients with moderate to severe periodontitis vs patients without history of periodontitis, which was maintained when the comparison was restricted to type 2 diabetics.

Prevalence of undiagnosed diabetes and pre-diabetes in chronic periodontitis patients assessed by an HbA1c chairside screening protocol

OBJECTIVES

The objective of the present study was to implement a chairside diabetes screening strategy for the identification of undiagnosed hyperglycaemia in periodontal patients.

MATERIALS AND METHODS

Measurement of HbA1c was performed in patients (n = 139) diagnosed with periodontal disease to determine possible unknown hyperglycaemia. Patients fulfilled the criteria for screening according to the questionnaire by the Centers for Disease Control and Prevention (CDC). The Cobas® b101 in vitro diagnostic system was used for the measurement of glycosylated haemoglobin (HbA1c) in capillary blood. Body mass index (BMI) and waist circumference were also measured to determine splanchnic obesity. Periodontal parameters were assessed with an automated probe and included probing depth, clinical attachment loss, bleeding on probing and presence/absence of plaque.

RESULTS

Most patients had moderate periodontitis. Almost 25% of the subjects tested were found to have unknown hyperglycaemia while 80.5% of them had splanchnic obesity. A significant association was found between HbA1c and BMI (Mann-Whitney test; p = 0.0021) as well as between HbA1c and waist circumference (Spearman rho test; p = 0.0007). No differences were observed regarding periodontal parameters between subjects exhibiting HbA1c ≥ 5.7% and those with HbA1c < 5.7% (Mann-Whitney test; p > 0.05) although those with HbA1c ≥ 5.7% displayed higher proportions of sites with clinical attachment loss > 5 mm (z test with Bonferroni corrections; p < 0.05).

CONCLUSIONS

Periodontal patients, especially those with a bigger than normal BMI and waist circumference, are a target group worth screening for diabetes.

CLINICAL RELEVANCE

The dental practitioner can contribute significantly to the worldwide effort of health care professionals in diabetes screening and referring for early diagnosis of the disease.

Periodontal Disease: A Risk Factor for Diabetes and Cardiovascular Disease

Periodontitis is a chronic inflammatory disease, initiated by the presence of a bacterial biofilm, called dental plaque, which affects both the periodontal ligaments and bone surrounding teeth. In the last decades, several lines of evidence have supported the existence of a relationship between periodontitis and systemic health. For instance, as periodontitis acts within the same chronic inflammatory model seen in cardiovascular disease (CVD), or other disorders, such as diabetes, several studies have suggested the existence of a bi-directional link between periodontal health and these pathologies. For instance, people with diabetes are more susceptible to infections and are more likely to suffer from periodontitis than people without this syndrome. Analogously, it is now evident that cardiac disorders are worsened by periodontitis, both experimentally and in humans. For all these reasons, it is very plausible that preventing periodontitis has an impact on the onset or progression of CVD and diabetes. On these grounds, in this review, we have provided an updated account on the current knowledge concerning periodontal disease and the adverse effects exerted on the cardiovascular system health and diabetes, informing readers on the most recent preclinical studies and epidemiological evidence.

Development and validation of a predictive model for periodontitis using NHANES 2011-2012 data

AIM

To develop and validate a predictive model for moderate-to-severe periodontitis in the adult USA population, with data from the 2011-2012 National Health and Nutrition Examination Survey (NHANES) cycle.

MATERIAL AND METHODS

A subset of 3017 subjects aged >30 years, with >14 teeth present and having received a periodontal examination in addition to data collected on cardio-metabolic risk measures (smoking habit, body mass index [BMI], blood pressure, total cholesterol and glycated haemoglobin [HbA1c]) were used for model development by multivariable logistic regression.

RESULTS

The prevalence of moderate and severe periodontitis using CDC/AAP classification was 37.1% and 13.2%, respectively. A multivariable logistic regression model revealed that HbA1c ≥5.7% was significantly associated with moderate-to-severe periodontitis (odds ratio, OR = 1.29; p < 0.01). A predictive model including age, gender, ethnicity, HbA1c and smoking habit as variables had 70.0% sensitivity and 67.6% specificity in detecting moderate-to-severe periodontitis in US adults.

CONCLUSIONS

Periodontitis is a common disease in North American adults, and its prevalence is significantly higher in individuals with pre-diabetes or diabetes. The present study demonstrates that a model including age, gender, ethnicity, HbA1c and smoking habit could be used as a reliable screening tool for periodontitis in primary medical care settings to facilitate referral of patients at risk for periodontal examination and diagnosis.

An Adiponectin Receptor Agonist Reduces Type 2 Diabetic Periodontitis

Periodontitis is twice as prevalent in diabetics as in nondiabetics, and type 2 diabetes (T2D)-associated periodontitis is severe in many cases due to the altered and aberrant functions of bone cells in hyperglycemic conditions. Therefore, developing an effective method to halt the disease process, as well as restore and regenerate lost alveolar bone to reserve the natural teeth in diabetics, is critically important. In the current study, we applied a newly discovered adiponectin receptor agonist AdipoRon (APR) in experimental periodontitis in diabetic animal models and demonstrated the underlying molecular mechanisms. We found that when APR systemically quenched the blood sugar level in diet-induced obesity (DIO) diabetic mice, it reduced osteoclast numbers and alveolar bone loss significantly due to APR's inhibition on osteoclast differentiation shown in our in vitro studies. APR also decreased the production of proinflammatory molecules CC chemokine ligand 2 and interleukin 6 in diseased gingival tissues. On the other hand, APR promoted alveolar bone regeneration through enhancing osteogenic differentiation and decreasing stromal cell-derived factor 1 in the bone marrow that facilitates stem cell migration. Same results were achieved by APR treatment of periodontitis induced in adiponectin (APN) knockout mice, indicating the ability of APR to activate the endogenous APN receptors to exert osteoanabolic effects. In summary, our study supports the notion that APR could be used as an effective multipronged approach to target T2D-associated periodontitis.

Periodontitis and mechanisms of cardiometabolic risk: Novel insights and future perspectives

Periodontitis is an infectious and inflammatory disease of the tooth-supporting tissues caused by the accumulation of subgingival plaque and the action of specific periodontopathogenic bacteria. Periodontitis has been associated with cardiovascular diseases and considered a cardiovascular risk factor. Several mechanisms have been proposed to explain this association, such as the infection of atherosclerotic plaques by periodontal pathogens, the pro-atherogenic effect on the lipid profile, the systemic dissemination of pro-inflammatory mediators or the contribution to type 2 diabetes mellitus. Periodontal treatment has also been related to improvement in cardiometabolic risk variables, and oral hygiene techniques may be useful in reducing cardiometabolic risk. The aim of this review is to provide new and recent insights on the relationship between periodontitis and cardiometabolic risk, focusing on recent evidence. Comments on shared potential therapeutic targets, such as the role of glucagon-like peptide 1, are also highlighted.

Enhanced Oxidative Damage and Nrf2 Downregulation Contribute to the Aggravation of Periodontitis by Diabetes Mellitus

Diabetes mellitus is a well-recognized risk factor for periodontitis. The goal of the present study was to elucidate whether oxidative stress and nuclear factor erythroid 2-related factor 2 (Nrf2) participate in the aggravation of periodontitis by diabetes. For this purpose, we assigned Wistar rats to control, periodontitis, diabetes, and diabetic periodontitis groups. Two weeks after induction of diabetes by streptozotocin, periodontitis was induced by ligation. Two weeks later, periodontal tissues and blood were harvested and analyzed by stereomicroscopy, immunohistochemistry, and real-time polymerase chain reaction. We found that ligation induced more severe bone loss and periodontal cell apoptosis in diabetic rats than in normal rats (p < 0.05). Compared with the control group, periodontitis significantly enhanced local oxidative damage (elevated expression of 3-nitrotyrosine, 4-hydroxy-2-nonenal, and 8-hydroxy-deoxyguanosine), whereas diabetes significantly increased systemic oxidative damage and suppressed antioxidant capacity (increased malondialdehyde expression and decreased superoxide dismutase activity) (p < 0.05). Simultaneous periodontitis and diabetes synergistically aggravated both local and systemic oxidative damage (p < 0.05); this finding was strongly correlated with the more severe periodontal destruction in diabetic periodontitis. Furthermore, gene and protein expression of Nrf2 was significantly downregulated in diabetic periodontitis (p < 0.05). Multiple regression analysis indicated that the reduced Nrf2 expression was strongly correlated with the aggravated periodontal destruction and oxidative damage in diabetic periodontitis. We conclude that enhanced local and systemic oxidative damage and Nrf2 downregulation contribute to the development and progression of diabetic periodontitis.

Simvastatin attenuates tibial bone loss in rats with type 1 diabetes and periodontitis

Background

Diabetes induces long bone loss and aggravation of periodontitis-induced alveolar bone loss. Simvastatin (SIM), which is a lipid-lowering agent is known to have an anabolic effect on bone. Therefore, we investigated effect of SIM on tibial and alveolar bone loss in type 1 diabetic rats with periodontitis.

Methods

Rats were divided into control (C), diabetes with periodontitis (DP), and diabetes with periodontitis treated with SIM (DPS) groups. DP and DPS groups were intravenously injected with streptozotocin (50 mg/kg), and C group was injected with citrate buffer. Seven days later (day 0), periodontitis was induced by ligatures of mandibular first molars. DP and DPS groups were orally administered vehicle or SIM (30 mg/kg) from day 0 to days 3, 10, or 20. Alveolar and tibial bone loss was measured using histological and m-CT analysis alone or in combination. Osteoclast number and sclerostin-positive osteocytes in tibiae were evaluated by tartrate-resistant acid phosphatase and immunohistochemical staining, respectively. Glucose, triglyceride (TG), cholesterol (CHO), and low-density lipoprotein (LDL) were evaluated.

Results

Consistent with diabetes induction, the DP group showed higher glucose and TG levels at all timepoints and higher CHO levels on day 20 than C group. Compared to the DP group, the DPS group exhibited reduced levels of glucose (day 3), TG (days 10 and 20), CHO, and LDL levels (day 20). Bone loss analysis revealed that the DP group had lower bone volume fraction, bone mineral density, bone surface density, and trabecular number in tibiae than C group at all timepoints. Interestingly, the DPS group exhibited elevation of these indices at early stages compared to the DP group. The DPS group showed reduction of osteoclasts (day 3) and sclerostin-positive osteocytes (days 3 and 20) compared with the DP group. There was no difference in alveolar bone loss between DP and DPS groups.

Conclusions

These results suggest that SIM attenuates tibial, but not alveolar bone loss in type 1 diabetic rats with periodontitis. Moreover, attenuation of tibial bone loss by SIM may be related to inhibition of osteoclast formation and reduction of sclerostin expression.

Potential risk factors for dental caries in Type 2 diabetic patients

BACKGROUND

Diabetic patients are known to be at higher risk for dental caries. However, the role of potential risk factors such as blood glucose, salivary glucose and glycaemic control in the occurrence of dental caries in type 2 diabetes (T2D) is not clearly understood so far, and therefore, it was evaluated in this study.

MATERIALS AND METHODS

This cross-sectional study was conducted on 100 T2D patients from Saudi Arabia. The caries risk assessment was evaluated using the guidelines of Caries Management by Risk Assessment (CAMBRA). Cariogenic bacteria load in saliva was determined by a chair-side test kit. The levels of fasting blood glucose (FBG), salivary glucose and HbA1c were analysed.

RESULTS

Majority of the patients had dental caries (84%), exposed root surfaces (92%) and heavy plaque (73%), whereas 66% of patients suffered from xerostomia. The frequency of patients with high counts of Streptococcus mutans and Lactobacilli (LB) were 78% and 42%, respectively. There were significant associations between dental caries risk and FBG, HbA1c and salivary glucose. After categorizing the patients into 3 categories of glycaemic control, we observed a significant association between glycaemic control and dental caries risk.

CONCLUSION

Type 2 diabetes patients are at high risk for dental caries, which is directly associated with FBG, HbA1c and salivary glucose. This is the first study measuring dental caries and its risk factors in T2D patients from Saudi Arabia.

Differences in Interleukin-8 Plasma Levels between Diabetic Patients and Healthy Individuals Independently on Their Periodontal Status

Chronic periodontitis (CP) and diabetes mellitus (DM) involve several aspects of immune functions, including neutrophil activity and cytokine biology. Considering the critical function of chemokine interleukin-8 (IL-8) in the inflammatory process, the aims of this study were to determine: (i) IL-8 plasma levels; (ii) IL-8 (-251A/T, rs4073) and its receptor 2 (CXCR2, +1208C/T, rs1126579) polymorphisms, and (iii) the presence of the selected periodontal bacteria in types 1 and 2 DM patients (T1DM and T2DM) and systemically healthy controls (HC) with known periodontal status. This case⁻control study comprises of 153 unrelated individuals: 36/44 patients suffering from T1DM+CP/T2DM+CP and 32/41 from HC+CP/non-periodontitis HC. Both the clinical and biochemical parameters were monitored. The genotypes were determined using qPCR, IL-8 plasma levels were measured using an ELISA kit. Subgingival bacterial colonization was analyzed with a DNA microarray detection kit. The IL-8 plasma levels differed significantly between non-periodontitis HC and T1DM+CP/T2DM+CP patients (P < 0.01). Even in HC+CP, IL-8 concentrations were significantly lower than in T1DM+CP/T2DM+CP patients (P ≤ 0.05). No significant associations between the IL-8 plasma levels and the studied IL-8 and CXCR2 polymorphisms or the occurrence of selected periodontal bacteria (P > 0.05) were found. CP does not influence the circulating IL-8 levels. Patients with T1DM+CP/T2DM+CP had higher circulating IL-8 levels than HC+CP/non-periodontitis HC.

Obesity alters composition and diversity of the oral microbiota in patients with type 2 diabetes mellitus independently of glycemic control

Background and objective

The involvement of the oral microbiota as a possible link between periodontitis, type 2 diabetes mellitus and obesity is still not well understood. The objective of the study was to investigate if glycemic control and obesity play a role in modulating the composition and diversity of the oral microbial ecology.

Material and methods

A cohort of patients with type 2 diabetes mellitus (n = 18) was recruited. Participants demonstrating improved glycemic control after 3 months (n = 6) were included in a second examination. A full mouth examination was performed to estimate periodontitis severity followed by sample collection (subgingival plaque and saliva). Generation of large sequence libraries was performed using the high-throughput Illumina MiSeq sequencing platform.

Results

The majority of participants (94.4%, n = 17) presented with moderate or severe forms of periodontitis. Differences in microbial composition and diversity between obese (BMI ≥ 30 kg/m²) and non-obese (BMI < 30 kg/m²) groups were statistically significant. Cross-sectional and longitudinal approaches failed to reveal statistically significant associations between HbA_1c level and species composition or diversity.

Conclusions

Obesity was significantly associated with the oral microbial composition. The impact of glycemic control on oral microbiota, however, could not be assured statistically.

Importance of Mechanical Periodontal Therapy in Patients with Diabetes Type 2 and Periodontitis

Periodontitis is an infectious and inflammatory disease of high prevalence worldwide and constitutes a significant oral health problem. It can lead to tooth loss. In addition, the local inflammatory process can cause the release of inflammatory mediators in the bloodstream and, consequently, contribute to the emergence of systemic effects as cardiovascular and diabetic complications. The purpose of this mini review is to alert health professionals about the risk that periodontitis represents for the onset or exacerbation of complications in individuals with type 2 diabetes mellitus and to emphasize that the mechanical treatment of periodontal disease and reestablishment of oral health are essential for the metabolic control of these patients. The periodontal therapy may help to reduce the risk of systemic complications in diabetes patients. Proper dental management should be suggested by health professionals, mainly from physicians to their patients, in order to improve the health conditions in these individuals.

The effects of periodontal treatment on diabetic patients: The DIAPERIO randomized controlled trial

AIM

To assess whether periodontal treatment can lead to clinical, glycaemic control and quality of life improvements in metabolically unbalanced diabetic patients (type 1 or type 2) diagnosed with periodontitis.

METHODS

In this open-labelled randomized controlled trial, diabetic subjects (n = 91) were given "immediate" or "delayed" periodontal treatment (full-mouth non-surgical scaling and root planing, systemic antibiotics, and oral health instructions). The main outcome was the effect on glycated haemoglobin (HbA_1C ) and fructosamine levels. The General Oral Health Assessment Index and the SF-36 index were used to assess quality of life (QoL).

RESULTS

Periodontal health significantly improved after periodontal treatment (p < 0.001). Periodontal treatment seemed to be safe but had no significant effects on glycaemic control based on HbA_1C (adjusted mean difference with a 95% confidence interval (aMD) of 0.04 [-0.16;0.24]) and fructosamine levels (aMD 5.0 [-10.2;20.2]). There was no obvious evidence of improvement in general QoL after periodontal treatment. However, there was significant improvement in oral health-related QoL (aMD 7.0 [2.4;11.6], p = 0.003).

CONCLUSION

Although periodontal treatment showed no clinical effect on glycaemic control in this trial, important data were provided to support periodontal care among diabetic patients. Periodontal treatment is safe and improves oral health-related QoL in patients living with diabetes. ISRCTN15334496.

SOD2 is upregulated in periodontitis to reduce further inflammation progression

OBJECTIVES

Periodontitis is a highly prevalent chronic inflammatory disease that results in destruction of tooth-supporting structures followed by tooth-loss. Until now, periodontitis has been regarded to be initiated by bacterial infection followed by aberrant host response. Although increasing evidence suggests a strong association between oxidative stress and periodontitis, precise molecular mechanism has been left unanswered. In this study, we investigated roles of SOD2, the main antioxidant enzyme maintaining reactive oxygen species (ROS) homeostasis, under inflammatory conditions.

METHODS

We computationally analyzed SOD2 expression in periodontitis. To confirm this data, immunoblot assay was performed with samples from periodontitis patients. The cellular mechanism of change in SOD2 expression was identified through immunoblot assay and immunofluorescence. To evaluate the molecular function of SOD2, we generated SOD2-deficient cells by utilizing the CRISPR/Cas9 system.

RESULTS

We first determined that SOD2 expression was significantly increased in periodontitis. We also confirmed that SOD2 expression was upregulated through the NF-κB pathway when the inflammatory signal was stronger and extended. Gene manipulation against SOD2 through the CRISPR/Cas9 system showed that the absence of SOD2 increased production of NLRP3 inflammasome components.

CONCLUSIONS

Our study demonstrates that intracellular SOD2 has a protective role by suppressing NLRP inflammasome-caspase-1-IL-1β axis under inflammatory conditions.