Inflammatory cytokines, adiponectin, insulin resistance and metabolic control after periodontal intervention in patients with type 2 diabetes and chronic periodontitis

Effects of amoxicillin and metronidazole as an adjunct to scaling and root planing on glycemic control in patients with periodontitis and type 2 diabetes: A short-term randomized controlled trial

OBJECTIVE

To assess the effects of amoxicillin and metronidazole with scaling and root planing (SRP) on periodontal parameters and glycemic control in patients with severe periodontitis and diabetes mellitus.

BACKGROUND

Adjunctive antibiotics use is advantageous for treating periodontitis in patients with severe periodontitis and diabetes. However, the effects of adjunctive antibiotic use on hemoglobin A1c (HbA1c) levels remain unclear.

METHODS

This short-term, randomized controlled trial enrolled patients with severe periodontitis and type 2 diabetes. The patients were randomly allocated to SPR only (i.e., control) or SPR + antibiotics (500 mg of amoxicillin and 200 mg of metronidazole, three times daily for 7 days) groups. Periodontal and hematological parameters were assessed at baseline and 3 months after treatment. Inter- and intra-group analyses were performed using Student's t-tests, Mann-Whitney U tests, and the binary logistic regression models. p-values of <.05 were considered statistically significant.

RESULTS

This study enrolled 49 patients, with 23 and 26 patients in the SRP-only and SRP + antibiotics groups, respectively. The periodontal parameters improved significantly and similarly in both groups after treatment (p < .05). The SRP + antibiotics group had more sites of improvement than the SRP-only group when the initial probing depth was >6 mm. (698 [78.96%] vs. 545 [73.35%], p = .008). The HbA1c levels decreased in the SRP-only and SRP + antibiotics groups after treatment (0.39% and 0.53%, respectively). The multivariable binary logistic regression model demonstrated that antibiotics administration and a high baseline HbA1c level were associated with a greater reduction in the HbA1c level (odds ratio = 4.551, 95% confidence interval: 1.012-20.463; odds ratio = 7.162, 95% confidence interval: 1.359-37.753, respectively).

CONCLUSIONS

SRP and SRP plus systemic antibiotics were beneficial for glycemic control. Adjunctive antibiotic use slightly improved the outcome for patients with severe periodontitis and poorly controlled diabetes.

Salivary and serum asprosin hormone levels in the 2018 EFP/AAP classification of periodontitis stages and body mass index status: a case-control study

OBJECTIVES

A newly discovered adipokine known asprosin in serum and saliva in patients with periodontitis has not been explored. The aim of this study was to determine the relationship between serum and saliva asprosin levels and periodontitis by grouping it according to body mass index (BMI).

MATERIALS AND METHODS

The study was conducted on 65 systemically healthy patients (35 patients with periodontitis (periodontitis group), 30 periodontally healthy patients (control group)). In each patient, age, BMI, and clinical periodontal parameters (plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment level (CAL)) were evaluated. Statistical analyses were conducted utilizing the Student t-test, ANOVA, and Pearson correlation analysis. For the significance level of the tests, p<0.05 were accepted.

RESULTS

The serum and saliva were collected to assess asprosin levels. Both the serum and saliva asprosin levels were statistically significantly higher in the periodontitis group than in the control group (p<0.001). Saliva and serum asprosin levels were directly proportional to the severity of the periodontal disease (p<0.05). Asprosin levels were higher in patients with a higher BMI (p<0.05).

CONCLUSION

Asprosin levels were increased in periodontitis, and even a high BMI status apparently affected the levels of this hormone. It is thought that asprosin may be a useful biomarker in evaluating the relationship between periodontal status and BMI.

CLINICAL RELEVANCE

Asprosin may be a useful parameter as a biomarker of periodontal disease progression. However, BMI status should be considered when evaluating asprosin levels in patients with periodontitis.

Endogenous and microbial biomarkers for periodontitis and type 2 diabetes mellitus

It has been well documented that there is a two-way relationship between diabetes mellitus and periodontitis. Diabetes mellitus represents an established risk factor for chronic periodontitis. Conversely, chronic periodontitis adversely modulates serum glucose levels in diabetic patients. Activated immune and inflammatory responses are noted during diabetes and periodontitis, under the modulation of similar biological mediators. These activated responses result in increased activity of certain immune-inflammatory mediators including adipokines and microRNAs in diabetic patients with periodontal disease. Notably, certain microbes in the oral cavity were identified to be involved in the occurrence of diabetes and periodontitis. In other words, these immune-inflammatory mediators and microbes may potentially serve as biomarkers for risk assessment and therapy selection in diabetes and periodontitis. In this review, we briefly provide an updated overview on different potential biomarkers, providing novel diagnostic and therapeutic insights on periodontal complications and diabetes mellitus.

Modulation of monocyte subtypes in diabetes after non-surgical periodontal treatment

OBJECTIVES

The current study aims to evaluate the effect of non-surgical periodontal treatment on the modulation of monocyte phenotype, in the presence or absence of diabetes.

MATERIALS AND METHODS

The identification, quantification, and phenotypic characterization of monocyte subtypes (classical, intermediate, and non-classical) were performed by flow cytometry, at baseline and 1 month after the end of non-surgical periodontal treatment, in patients with periodontitis, associated or not with diabetes.

RESULTS

There was an increase in non-classical monocytes after treatment and a reduction in intermediate monocytes, without differences for the classical subtype, regardless of the diabetes status. Furthermore, there was a reduction in intermediate monocytes and an increase in non-classical and classical monocytes after treatment in the diabetes group, while no significant differences were observed for classical, intermediate, and non-classical monocytes in the group without diabetes. Comparisons between the two groups showed significant differences for classical, intermediate, and non-classical monocytes at baseline; these differences were not found one month after treatment.

CONCLUSIONS

Non-surgical periodontal treatment leads to modulation of monocytes to a less inflammatory phenotype, especially in individuals with diabetes.

CLINICAL RELEVANCE

A better understanding of the role of these biomarkers in the periodontitis contex may constitute a new strategic target for a better treatment of patiens with diabetes associated to periodontitis.

CLINICAL TRIAL REGISTRATION

Brazilian Registry of Clinical Trials-RBR-35szwc. Jhefferson Miranda Alves and Danielle Borges Germano contributed equality to this study and should be considered first authors.

Effect of periodontal therapy on insulin resistance in adults with dysglycemia and periodontitis: a systematic review and meta-analysis

OBJECTIVES

This systematic review and meta-analysis aimed to address whether non-surgical periodontal therapy (NSPT) can affect insulin resistance, estimated by the homeostasis model assessment (HOMA), in adults with prediabetes or type 2 diabetes mellitus and periodontitis.

MATERIALS AND METHODS

Six electronic databases and the gray literature were systematically searched for interventional studies reporting NSPT effect on insulin resistance. Seven studies met the eligibility criteria to be synthesized in the qualitative analysis, six reporting change in HOMA-IR, three reporting change in HOMA-%S, and two in HOMA-β. Among them, four were pooled in a meta-analysis of standardized mean difference (SMD) of HOMA-IR; comparing pre- and post-intervention values, three were pooled considering HOMA-%S as outcome, and two studies were summarized considering SMD of HOMA-%S between intervention and control groups. HOMA-β results were qualitatively synthetized.

RESULTS

With low level of certainty, NSPT significantly reduced HOMA-IR, when compared with pre-intervention data (SMD, -0.35, 95% CI -0.63 to 0.07, p=0.02). There were no significant changes in HOMA-%S or in HOMA-β scores. The level of certainty was very low and moderate, respectively.

CONCLUSIONS

Assertions about a causal link between NSPT and insulin resistance are weak and conflicting, although our more robust results point out to the absence of effect. .

CLINICAL RELEVANCE

Because further high-quality studies assessing the relationship between periodontitis and insulin resistance are need, the findings of the current systematic review are limited to give recommendations for clinicians. However, while identifying a lack of research in humans with T2D concerning periodontitis and insulin resistance, this study reinforces the need of multicenter well-designed randomized clinical trials.

Periodontitis treatment (surgical and nonsurgical) effects on glycemic control: A review and meta-analysis

Background

Periodontitis is the sixth most prevalent chronic disease. Literature suggests a relationship between diabetes and periodontitis and when coexist may aggravate each other deleterious consequences. Therefore, we aimed to assess the effects of periodontitis treatment on glycemic control.

Materials and Methods

A systematic literature search was conducted in PubMed, Cochrane Library, and the first 100 articles in Google Scholar from January 2011 to October 2021. The terms periodontitis, periodontal treatment, diabetes mellitus, nonsurgical treatment, glycated hemoglobin (HbA1c) were used, with the Protean "AND" and "OR." The titles, abstracts, and references of the included studies were screened. Any discrepancy was solved by an agreement between researchers. Out of 1059 studies retrieved, 320 stands after the removal of duplication, from them, 31 full texts were screened and only 11 studies were included in the final meta-analysis.

Results

In the present meta-analysis, 11 studies (1469 patients included) were pooled, and the overall effect showed that periodontitis treatment improved the HbA1c, odd ratio, -0.024, 95% confidence interval, -0.42-.06, P value, 0.009, Chi-square, 52.99. However, substantial heterogeneity was observed, P value, < 0.001, I² for heterogeneity 81%.

Conclusion

Periodontitis treatment improved the HbA1c among patients with diabetes and poor glycemic control. Screening of this common disease is important in diabetes holistic care.

Nonsurgical periodontal treatment improved the type 2 diabetes mellitus status in smokers: A randomized controlled trial

AIM

Type 2 diabetes mellitus (T2D) and periodontal disease have bilateral associations. The effect of periodontal treatment on T2D patients who smoke is scarce. This study aimed to assess the effect of nonsurgical periodontal treatment (NSPT) in periodontitis smokers with T2D for a duration of 6 months of follow-up.

MATERIALS AND METHODS

Forty moderate to severe periodontitis smokers with T2D were randomly distributed into two different treatment groups: the test group (NSPT including oral hygiene instructions, scaling and root planing; and 0.05% Chlorhexidine mouthrinse) and the control group (treatment including oral hygiene instructions, supragingival removal of plaque and calculus and 0.05% Chlorhexidine mouthrinse). Periodontal parameters including plaque index (PI), gingival index (GI), bleeding on probing (BOP), periodontal probing depth (PPD) and clinical attachment loss (CAL) were examined. Metabolic parameters, including fasting plasma glucose (FPG) and glycated hemoglobin (HbA1c), and high-sensitivity C-reactive protein (hs-CRP) were evaluated at baseline and at 1, 3, and 6 months of follow-up.

RESULTS

The test group significantly improved all periodontal parameters and reduced metabolic parameters and hs-CRP, whereas improvements in PI and GI were observed in the control group at 1, 3 and 6 months of follow-up. However, the PPD, CAL, metabolic parameters and hs-CRP increased in the control group at 3 and 6 months of follow-up, but the differences were not significant.

CONCLUSIONS

NSPT improves the periodontal status of smokers with T2D, has a favorable effect on glycemic control and reduces pro-inflammatory mediators, which may limit complications due to T2D in these patients.

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

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

Periodontal disease and systemic health: An update for medical practitioners

INTRODUCTION

Chronic periodontal disease is a highly prevalent dental condition affecting tooth-supporting tissues. Scientific evidence is accumulating on links between periodontal disease and various systemic conditions. This narrative review provides a holistic yet succinct overview that would assist medical practitioners to deliver integrated care for better clinical outcomes.

METHOD

Scientific evidence on associations between periodontal disease and systemic conditions was synthesised and critically appraised. Key findings of latest prospective cohort studies, randomised clinical trials, and meta-analysis were closely assessed and compiled.

RESULTS

A bidirectional relationship has been established, indicating that diabetes and periodontal disease are closely linked and amplify one another, if not successfully controlled. Existing evidence also supports the associations of periodontal disease with cardiovascular diseases and adverse pregnancy outcomes. Successful treatment of periodontal disease and dental prophylaxis has been shown to improve clinical outcomes in these systemic conditions. Other systemic conditions associated with periodontal disease include respiratory diseases, Alzheimer's disease, rheumatoid arthritis and chronic kidney disease. Although the underlying mechanisms remain to be fully elucidated, it is generally accepted that the inflammatory burden of chronic periodontal disease has an important systemic impact.

CONCLUSION

Oral-systemic links are multifaceted and complex. While evidence linking periodontal disease with a variety of systemic conditions is still emerging, the nature of the relationship is becoming clearer. The updated understanding of these associations warrants the attention of medical experts and policymakers for a concerted effort to develop a patient-centric, integrated model for the treatment of comorbid dental and medical conditions.

The Effects of 810 nm Diode Laser and Indocyanine Green on Periodontal Parameters and HbA1c in Patients with Periodontitis and Type II Diabetes Mellitus: A Randomized Controlled Study

The aim of this study was to investigate the effects of adjunctive periodontal therapy of 5 mg/mL indocyanine green irradiation by an 810 nm diode laser (aPDT), supplementary to scaling and root planing (SRP) in patients with periodontitis and type II diabetes mellitus (DM) compared to the SRP alone, on periodontal clinical parameters and glycated hemoglobin A1c (HbA1c). The study was conducted on 49 subjects with type II DM and periodontitis, divided into two groups: the SRP group (n = 25), who followed SRP alone, and the SRP + aPDT group (n = 24), who followed SRP and four weekly sessions of indocyanine green irradiation by an 810 nm diode laser. Plaque Index (PI), Bleeding on Probing Index (BOP), probing depth (PD), clinical attachment loss (CAL) and HbA1c were investigated at baseline and after 6 months. At 6 months, both SRP alone and SRP + aPDT generated significant reductions in all the investigated parameters; SRP + aPDT produced more significant reductions for BOP, PD and CAL (p < 0.001) but not for PI and HbA1c, than SRP alone. aPDT with indocyanine green therapy was well tolerated, with two subjects reporting slight discomfort. Therefore, aPDT with indocyanine green might represent a good adjunctive periodontal treatment option for SRP in patients with type II DM and periodontitis.

Periodontal diseases assessed by average bone resorption are associated with microvascular complications in patients with type 2 diabetes

Periodontal disease often develops in patients with diabetes, and further exacerbated with diabetic complications. It would be clinically important to clarify the relationship between diabetic microvascular diseases and periodontal disease. This study aimed to evaluate the association between periodontal disease and diabetic complications in patients with type 2 diabetes with poor glycemic control. A total of 447 patients with type 2 diabetes hospitalized at Rakuwakai Otowa Hospital, Japan, were initially recruited in this study. After excluding 134 patients who lacked clinical data or were edentulous, 312 were included in our study. The severity of periodontal disease was evaluated based on the average bone resorption rate. Patients with diabetic nephropathy developed severe periodontal disease (multivariate-adjusted odds ratio, 3.00 [95% CI 1.41-5.19]). Diabetic neuropathy was positively associated with the severity of periodontal disease; the multivariate-adjusted odds ratio (95% CI) was 1.62 (0.87‒2.99) for moderate and 4.26 (2.21‒8.20) for severe periodontal disease. In contrast, diabetic retinopathy was linked with moderate periodontal disease (multivariate-adjusted odds ratio 2.23 [95% CI 1.10-4.10]), but not with severe conditions (multivariate-adjusted odds ratio 0.92 [95% CI 0.67-3.07]). In conclusion, periodontal disease, evaluated by average bone resorption rate, was associated with diabetic nephropathy and neuropathy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-022-00591-0.

Treatment of periodontitis for glycaemic control in people with diabetes mellitus

BACKGROUND

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

SEARCH METHODS

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Association between the frequency of toothbrushing and lifestyle in people with type 2 diabetes mellitus: at the baseline date of the Kamogawa-DM cohort study

It has been reported that oral health is associated with some co-morbid conditions, including cardiovascular disease, in people with type 2 diabetes mellitus. The present study investigated the association between the frequency of toothbrushing and lifestyle in people with type 2 diabetes mellitus. This cross-sectional study included 624 outpatients at the Kyoto Prefectural University of Medicine in Kyoto, Japan from January 2014 to January 2016. Lifestyle was evaluated using a self-administered questionnaire. The average age and hemoglobin A1c level were 67.6 ± 10.9 years and 7.2 ± 1.1%, respectively. The number of patients who brushed their teeth twice or more a day was 189 (50.3%) in men and 198 (79.8%) in women. Among men, the proportion of patients living alone was lower in those who brushed their teeth twice or more a day than those who brushed their teeth never/rarely or once a day. The logistic regression analysis, after adjusting for confounding factors, revealed that living alone (odds ratio 2.88; 95% confidence interval 1.53–5.66) was associated with the increased odds of the low frequency of toothbrushing (never/rarely or once a day) in men, but not in women. In conclusion, the results of our study suggest that living alone was associated with the low frequency of toothbrushing in people with type 2 diabetes mellitus, particularly in men.

Effects of Metronidazole as an Adjunct to Non-Surgical Periodontal Therapy on Insulin Resistance in Type 2 Diabetics

Treating periodontitis with metronidazole (MET) as an adjunct to scaling root planing (SRP) is suggested to have inconsistent effects on insulin resistance (IR) in type 2 diabetes mellitus (T2DM). This paper will present the effects of MET, in addition to SRP, on the homeostatis model assessment of IR (HOMA-IR). A three-arm clinical trial was conducted and analyses were performed on T2DM participants with periodontitis (n = 74) who completed follow-up visits at 3 and 6 months after the intervention. The observed between-group and within-group mean changes in IR were found using ANOVA with repeated measures, followed by a post-hoc analysis, and a p-value of ≤0.05 was considered significant. Between-group analyses showed no difference in the HOMA-IR at 3 months, but at 6 months the difference was significant (p = 0.046). Within-group analyses showed that the HOMA-IR was significantly reduced in both test groups (p ≤ 0.05) over the period of time. Adjunct use of MET may result in a sudden short-term lowering of the HOMA-IR level within 3 months that may not be retained over 6 months when compared to the sustained lowering of the HOMA-IR levels in T2DM when intervened with SRP without MET.

Physical activity as a proxy to ameliorate inflammation in patients with type 2 diabetes and periodontal disease at high cardiovascular risk

While the beneficial impact of physical activity has been ascertained in a variety of pathological scenarios, including diabetes and low-grade systemic inflammation, its potential remains still putative for periodontal health. Periodontal disease has been associated with inflammatory systemic alterations, which share a common denominator with type 2 diabetes mellitus and cardiovascular disease. Physical exercise, along with nutritional counseling, is a cornerstone in the treatment and prevention of type 2 diabetes, also able to reduce the prevalence of periodontal disease and cardiovascular risk. In addition, considering the higher incidence of periodontitis in patients with type 2 diabetes compared to healthy controls, the fascinating research question would be whether physical activity could relieve the inflammatory pressure exerted by the combination of these two diseases. This multi-disciplinary viewpoint discusses available literature in order to argument the hypothesis of a "three-way relationship" linking diabetes, periodontitis, and physical activity.

Characterization of salivary microbiota in elderly patients with type 2 diabetes mellitus: a matched case-control study

OBJECTIVE

The importance of oral health in type 2 diabetes mellitus (T2DM) is widely recognized; however, oral microbiota characteristics associated with T2DM in the elderly population are not well-understood. This study was conducted to evaluate the characteristics of the salivary microbiota in elderly Japanese patients with T2DM.

METHODS

Saliva samples were collected from 42 elderly Japanese patients with T2DM and 42 age- and sex-matched subjects without T2DM (control). 16S ribosomal RNA metagenomic analysis and comparative analysis of both groups were performed. Random forest classification by machine learning was performed to discriminate between the salivary microbiota in the two groups.

RESULTS

There were significant differences in the overall salivary microbiota structure between the T2DM and control groups (beta diversity; unweighted UniFrac distances, p = 0.001; weighted UniFrac distances, p = 0.001). The phylum Firmicutes was abundant in patients with T2DM, whereas the phylum Bacteroidetes was abundant in controls. The T2DM prediction model by random forest based on salivary microbiota data was verified with a high predictive potential in five cross-validation tests (area under the curve (AUC) = 0.938 (95% CI, 0.824-1.000)).

CONCLUSION

Characterization revealed that the salivary microbiota profile of the elderly patients with T2DM is significantly distinct from that of the controls.

CLINICAL RELEVANCE

These data indicate the necessity of oral health management based on the characteristics of the salivary microbiota in elderly patients with T2DM. Our findings will contribute to future research on the development of new diagnostic and therapeutic methods for this purpose.

Adiponectin inhibits lipoplysaccharide-induced inflammation and promotes osteogenesis in hPDLCs

Periodontal diseases are infections of the structures that surround and support the teeth; they are characterized by local inflammation and alveolar bone loss. Most treatments focus on only one aspect, inhibiting inflammation, or promoting osteoblasts. We set out to develop a new method that would intervene in the two aspects simultaneously. Adiponectin (APN), secreted by adipocytes, inhibits the inflammatory response and promotes osteogenesis. However, its role in human periodontal ligament cells (hPDLCs) is unclear. Therefore, we aim to investigate whether APN could suppress lipopolysaccharide (LPS)-induced inflammation and promote osteogenesis in hPDLCs. In the present study, we stimulated hPDLCs with LPS in the presence or absence of APN. Real-time PCR and Western blotting results demonstrated that APN partially inhibited the activation of the classical nuclear factor κ-B (NF-κB) pathway. These results were confirmed by a change of expressions of NF-κB downstream inflammatory genes, such as decreased cyclooxygenase (COX)-2 and tumor necrosis factor α (TNF-α), along with increased interleukin (IL)-10. As for the role of APN in osteogenesis, Alizarin Red S staining showed that APN treatment induced more calcium deposition nodules than controls. We also found that APN enhanced the expression of osteoblast-related genes (osteopontin (OPN), collagen 1, osteocalcin, alkaline phosphatase, runt-related transcription factor 2 (RUNX2), and bone morphogenetic protein 2) in hPDLCs via the APPL1 (the adaptor protein containing PH domain, PTB domain, and leucine zipper motif 1)/p38 signal transduction pathway. Therefore, APN inhibits LPS-induced inflammation and promotes osteogenesis in hPDLCs and may have potential therapeutic value in treating periodontitis by inhibiting the inflammatory lesions and contributing to bone tissue regeneration.

The role of adiponectin in periodontitis: Current state and future prospects

Adiponectin (APN), which is an adipokine primarily secreted by adipose tissue into the peripheral blood, exerts anti-inflammatory and metabolic regulatory functions in many systemic inflammatory diseases. Periodontitis is a localized inflammatory disease and is also the sixth-leading complication of diabetes. Uncontrolled periodontal inflammation gradually destructs the periodontal supporting apparatus and leads to the consequent loss of teeth. Recently, emerging evidence has revealed an association between APN and periodontitis. Herein, we summarize the basic information of APN and its receptor agonists. We also overview current studies considering the role of APN in periodontitis and discuss the potential mechanisms in terms of inflammation and bone metabolism. At last, we outline the correlation between APN and systemic diseases related periodontitis. Above all, APN and its agonists are promising candidates for the treatment of periodontitis, while the underlying mechanisms and clinical translational application require further exploration.

Short-term effect of non-surgical periodontal treatment on local and systemic cytokine levels: Role of hyperglycemia

BACKGROUND

The effect of non-surgical periodontal treatment on oral and systemic inflammatory mediators in subjects with periodontitis and hyperglycemia remains largely unknown. Therefore, the aim of this clinical study was to compare the short-term effect of non-surgical periodontal treatment on serum, saliva and GCF inflammatory markers levels in GP subjects with or without hyperglycemia.

METHODS

Sixty subjects divided into four groups of equal size were selected to participate: type 2 diabetics with generalized periodontitis (T2DM + GP), pre-diabetics with GP (PD + GP), normoglycemic subjects with GP (NG + GP), and healthy controls. GCF, serum, and saliva samples were obtained at baseline and 30 days after scaling and root planning (SRP) and the levels of interleukin-1β (IL-1 β), IL-8, IL-6, IL-2, IL-5, IL-4, IL-10, Interferon gamma (IFN-γ), Granulocyte macrophage colony-stimulating factor (GM-CSF) and Tumor necrosis factor-alpha (TNF-α) were determined by ultrasensitive multiplex assay. Clinical periodontal measurements were recorded.

RESULTS

SRP yielded significant improvement of all periodontal parameters for all GP groups (p < 0.01). A significant reduction in GCF levels of several cytokines were observed; however, only IL-1B and IFN-γ were consistently reduced post-treatment across all GP groups. Salivary levels of IL-1β were significantly reduced in all GP groups following treatment. No significant differences were observed for serum levels after SRP.

CONCLUSIONS

Periodontal treatment reduced local inflammatory markers, specifically IL-1B and IFN-γ, irrespective of the diabetes status. Periodontal treatment had no significant effect on serum levels of the inflammatory markers evaluated in this study.

Salivary biomarkers for discriminating periodontitis in the presence of diabetes

AIM

Salivary biomarkers can help in assessment of periodontitis; however, concentrations may be altered in the presence of diabetes. Hence, the ability of salivary biomarkers to discriminate periodontally healthy type II diabetics (T2DM) from T2DM who have periodontitis was examined.

METHODS

Ninety-two participants (29 with T2DM with chronic periodontitis, DWP; 32 T2DM without chronic periodontitis, DWoP; and 31 Not Periodontitis, NP) provided saliva and clinical parameters of periodontal health were recorded. Salivary concentrations of interleukin (IL)-1β, IL-6, matrix metalloproteinase-8 (MMP-8), macrophage inflammatory protein-1α (MIP-1α), adiponectin and resistin were measured by immunoassay.

RESULTS

Salivary analyte concentrations for IL-1β, MMP-8 and resistin correlated with clinical parameters of periodontitis, with MMP-8 demonstrating the strongest positive correlation with PD ≥5 mm (p < 0.0001). Periodontal health was reflected in salivary analyte concentrations by group, with concentrations of IL-1β and MMP-8 showing significant associations with periodontitis (p ≤ 0.04) that increased in concentration from health to DWoP to DWP. Odds ratio (OR) analyses showed that MMP-8 discriminated periodontitis from NP (OR of 8.12; 95% CI: 1.01-65.33; p = 0.03) and in the presence of T2DM (DWP vs DWoP, OR = 5.09; 95% CI: 1.24-20.92; p = 0.03).

CONCLUSION

Salivary MMP-8 and IL-1β discriminate periodontitis in T2DM.

A review of T helper 17 cell-related cytokines in serum and saliva in periodontitis

Periodontitis is a chronic inflammatory disease with a complex underlying immunopathology. Cytokines, as molecular mediators of inflammation, play a role in all stages of disease progression. T helper 17 (Th17) cells are thought to play a role in periodontitis. Th17 cell development and maintenance requires a pro-inflammatory cytokine milieu, with many of the cytokines implicated in the pathogenesis of periodontitis. Serum and saliva are easily accessible biofluids which can represent the systemic and local environment to promote the development of Th17 cells. Here we review human clinical studies that investigate IL-1β, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IFN-γ, sCD40L and TNF-α in serum and saliva in periodontitis. We highlight their putative role in the pathogenesis of periodontitis and place them within a wider context of animal and other clinical studies.

Acute and chronic diabetes complications associated with self-reported oral health: a retrospective cohort study

BACKGROUND

Oral health is associated with diabetes, but the chances of experiencing acute or chronic diabetes complications as per this association is unknown in Canada's most populous province, Ontario. This study assesses the impact of self-reported oral health on the likelihood of experiencing acute and chronic complications among a cohort of previously diagnosed diabetics.

METHODS

A retrospective cohort study was conducted of diabetics (n = 5183) who participated in the Canadian Community Health Survey 2003 and 2007-08. Self-reported oral health status was linked to health encounters in electronic medical records until March 31, 2016. Multinomial regression models determined the odds of the first acute or chronic complication after self-report of oral health status.

RESULTS

Thirty-eight percent of diabetics reporting "poor to fair" oral health experienced a diabetes complication, in comparison to 34% of those reporting "good to excellent" oral health. The odds of an acute or chronic complication among participants reporting "poor to fair" oral health status was 10% (OR 1.10; 95% CI 0.81, 1.51) and 34% (OR 1.34; 95% CI 1.11, 1.61) greater respectively, than among participants experiencing no complications and reporting "good to excellent" oral health.

CONCLUSION

Self-reporting "poor to fair" oral health status is associated with a greater likelihood of chronic complications than acute complications. Further research regarding the underlying causal mechanisms linking oral health and diabetes complications is needed.

Comparative In Vitro Resistance of Human Periodontal Bacterial Pathogens to Tinidazole and Four Other Antibiotics

The in vitro resistance of selected red/orange complex periodontal pathogens to tinidazole was compared with four other antibiotics. Subgingival biofilm samples from 88 adults with severe periodontitis were anaerobically incubated on enriched Brucella blood agar with and without supplementation with tinidazole (16 mg/L), metronidazole (16 mg/L), amoxicillin (8 mg/L), doxycycline (4 mg/L), or clindamycin (4 mg/L). Growth of Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia/nigrescens, Parvimonas micra, Fusobacterium nucleatum, Streptococcus constellatus, or Campylobacter rectus on antibiotic-supplemented plates indicated their in vitro antibiotic resistance. Tinidazole inhibited all test species, except P. intermedia/nigrescens, P. micra, and S. constellatus in 3.8%, 10.2%, and 88.9% of species-positive patients, respectively. Significantly fewer patients yielded tinidazole-resistant test species, and had significantly lower subgingival proportions of tinidazole-resistant organisms, than patients with amoxicillin, doxycycline, or clindamycin-resistant species, but not those with metronidazole-resistant strains. Joint in vitro species resistance to tinidazole and amoxicillin, or metronidazole and amoxicillin, was rare. Tinidazole performed in vitro similar to metronidazole, and markedly better than amoxicillin, doxycycline, or clindamycin, against fresh clinical isolates of red/orange complex periodontal pathogens. As a result of its similar antimicrobial spectrum, and more convenient once-a-day oral dosing, tinidazole should be considered in place of metronidazole for systemic periodontitis drug therapy.

Therapeutic significance of β-glucuronidase activity and its inhibitors: A review

The emergence of disease and dearth of effective pharmacological agents on most therapeutic fronts, constitutes a major threat to global public health and man's existence. Consequently, this has created an exigency in the search for new drugs with improved clinical utility or means of potentiating available ones. To this end, accumulating empirical evidence supports molecular target therapy as a plausible egress and, β-glucuronidase (βGLU) - a lysosomal acid hydrolase responsible for the catalytic deconjugation of β-d-glucuronides has emerged as a viable molecular target for several therapeutic applications. The enzyme's activity level in body fluids is also deemed a potential biomarker for the diagnosis of some pathological conditions. Moreover, due to its role in colon carcinogenesis and certain drug-induced dose-limiting toxicities, the development of potent inhibitors of βGLU in human intestinal microbiota has aroused increased attention over the years. Nevertheless, although our literature survey revealed both natural products and synthetic scaffolds as potential inhibitors of the enzyme, only few of these have found clinical utility, albeit with moderate to poor pharmacokinetic profile. Hence, in this review we present a compendium of exploits in the present millennium directed towards the inhibition of βGLU. The aim is to proffer a platform on which new scaffolds can be modelled for improved βGLU inhibitory potency and the development of new therapeutic agents in consequential.

Resistin Is Increased in Periodontal Cells and Tissues: In Vitro and In Vivo Studies

Resistin, a proinflammatory adipokine, is elevated in many inflammatory diseases. However, little is known about its performance in periodontitis. The present study is aimed at evaluating resistin expression and synthesis in periodontal cells and tissues under inflammatory/microbial stress in addition to its effects on the periodontium. In vivo, 24 male rats were randomly divided into two groups: control and ligature-induced periodontal disease. After 6 and 12 days, animals were sacrificed to analyze gene expression of adipokines, bone loss, inflammation, and resistin synthesis. In vitro, human periodontal ligament (PDL) fibroblasts were used to evaluate the expression of resistin after inflammatory stimuli. In addition, PDL fibroblasts were exposed to resistin to evaluate its role on soft and hard tissue metabolism markers. The periodontitis group demonstrated significant bone loss, an increase in the number of inflammatory cells and vascular structures, an increase in resistin expression and synthesis, and a decrease in the expression of adiponectin, leptin, and its functional receptor. PDL fibroblasts showed a significant increase in resistin expression and synthesis in response to the inflammatory stimulus by IL-1β. Resistin induced an increase in cytokine expression and a decrease in the regulation of some hard tissue and matrix formation genes in PDL fibroblasts. These data indicate that resistin is produced by periodontal cells and tissues, and this effect is enhanced by inflammatory stimuli. Moreover, resistin seems to interfere with soft and hard tissue metabolism during periodontitis by reducing markers related to matrix formation and bone tissue.

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.

Periodontal Therapy for Improving Lipid Profiles in Patients with Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

Periodontitis is a chronic inflammatory disorder often seen in patients with diabetes mellitus (DM). Individuals with diabetes are at a greater risk of developing cardiovascular complications and this may be related, in part, to lipid abnormalities observed in these individuals. The objective of this systematic review is to compile the current scientific evidence of the effects of periodontal treatment on lipid profiles in patients with type 2 diabetes mellitus. Through a systematic search using MEDLINE, EMBASE, PubMed, and Web of Science, 313 articles were identified. Of these, seven clinical trials which met all inclusion criteria were chosen for analysis. Between baseline and 3-month follow-up, there was a statistically significant reduction in the levels of total cholesterol (mean differences (MD) −0.47 mmol/L (95% confidence interval (CI), −0.75, −0.18, p = 0.001)), triglycerides (MD −0.20 mmol/L (95% CI −0.24, −0.16, p < 0.00001)) favouring the intervention arm, and a statistically significant reduction in levels of high density lipoprotein (HDL) (MD 0.06 mmol/L (95% CI 0.03, 0.08, p < 0.00001)) favouring the control arm. No significant differences were observed between baseline and 6-month follow-up levels for any lipid analysed. The heterogeneity between studies was high. This review foreshadows a potential benefit of periodontal therapy for lipid profiles in patients suffering from type 2 DM, however, well designed clinical trials using lipid profiles as primary outcome measures are warranted.

Effectiveness of an Oral Health Promotion Program for the Elderly in Khiri Mat District, Sukhothai Province: A Randomized Control Trial

Objectives:

Oral disease is one of the most common health problems among the elderly, which impacts the quality of life. Applying the Health Belief Model (HBM) in oral health promotion is expected to improve the effectiveness of prevention and promotion that restricts oral health problems. The aim of the present study was to determine the effectiveness of an oral health promotion program on oral health behavior and oral status among the elderly in Khiri Mat, Thailand.

Materials and Methods:

A prospective randomized control trial was carried out among 162 elderly people for 6 months. They were interviewed to gather oral health behaviors and perception information, followed by an oral health examination. The experimental group received oral health education based on the HBM theory and tooth brushing practice in a small group of 4–5 persons, and then they were remotivated to support behavior change at 1 and 3 months. The control group received traditional oral health activity. All the elderly were followed up at 6 months. Data were analyzed using the t-test, Mann–Whitney test, Chi-square, and logistic regression.

Results:

The elderly in the experimental group had significantly higher oral health perception, lower plaque scores, lower gingival inflammation, and lower clinical attachment loss than those in the control group (P < 0.05).

Conclusion:

This oral health promotion program improved oral health perception, behavior, and oral health status of the elderly.

Advanced glycosylated end products restrain the osteogenic differentiation of the periodontal ligament stem cell

BACKGROUND/PURPOSE

Many studies have confirmed that periodontal disease interacts with diabetes. The aim of this study was to examine whether the advanced glycosylated end products (AGEs), which are generated by diabetics, have important effects on the osteogenic differentiation of periodontal ligament stem cells (PDLSCs).

MATERIALS AND METHODS

In this study PDLSCs were isolated from the periodontal ligaments of extracted third molar teeth. The subjects were divided into two groups, which included the normal control group (N-PDLSCs) and the AGEs-stimulating group (A-PDLSCs). Changes of receptor of AGEs (RAGE) and cumulative ROS in PDLSCs were monitored by western blot and flow cytometry, respectively.

RESULTS

In the study AGEs noticeably inhibited the osteogenic differentiation of PDLSCs, with significant lower calcification nodules detected in A-PDLSCs (P < 0.01). RAGE expression level and ROS accumulation in A-PDLSCs were clearly higher than those in N-PDLSCs (P < 0.01).

CONCLUSION

Our conclusions were that AGEs may cause the apoptosis of stem cells, which could lead to the disorder of bone differentiation function of PDLSCs.

Interactions among moderate/severe periodontitis, ADIPOQ-rs1501299, and LEPR-rs1137100 polymorphisms on the risk of type 2 diabetes in a Chinese population

OBJECTIVE

Type 2 diabetes mellitus (T2DM) is a complex disease influenced by genes and the environment. Periodontitis a demonstrated risk factor of T2DM. Previous studies related to gene-environment interactions on the risk of T2DM mainly focused on gene-obesity interactions. However, the impact of gene-periodontitis interaction on the risk of T2DM has not yet been investigated. This study aimed to investigate gene-environment interactions among moderate/severe periodontitis, polymorphisms of adiponectin (ADIPOQ)-rs1501299, and leptin receptor (LEPR)-rs1137100 on T2DM risk in Chinese subjects.

DESIGN

A case-control study was conducted in 239 Chinese participants from Beijing Hypertension Association Institute (BHAL). After full-mouth periodontal examinations, the participants underwent bilateral buccal swabs for DNA testing. ADIPOQ-rs1501299 and LEPR-rs1137100 were used for genotyping. Generalised multifactor dimensionality reduction (GMDR) and logistic regression were used to examine the interactions among single nucleotide polymorphisms (SNPs) and moderate/severe periodontitis on the risk of T2DM.

RESULTS

The risk of T2DM was higher in moderate/severe periodontitis [adjusted odds ratio (AOR) = 3.67, 95% confidence interval (95%CI): 1.26-10.71] in ADIPOQ-rs1501299 GG genotype (AOR = 3.42, 95%CI: 1.81-6.46) and LEPR-rs1137100 GG genotype (AOR = 3.16, 95%CI: 1.56-6.39). The GMDR model indicated that there was a significant three-factor model (p = 0.001) involving rs1501299, rs1137100, and moderate/severe periodontitis, demonstrating a potential gene-environment interaction among periodontitis, polymorphisms of rs1501299, and rs1137100 influencing the risk of T2DM. Moderate/severe periodontitis patients with rs1501299-GG and rs1137100-GG have the highest T2DM risk after adjusting for age, gender, BMI, WHR, smoking status, alcohol consumption, economic status, and hypertension (AOR = 20.39, 95%CI: 2.64-157.26).

CONCLUSIONS

Interactions among moderate/severe periodontitis, rs1501299-GG, and rs1137100-GG were associated with an increased risk of T2DM. This study may provide a new insight into the effect of gene-environment interactions on T2DM.

Efficacy of Brief Lifestyle Change in conjunction with Dental Care (Brief-LCDC) Programs on glycemic and periodontal status among DM patients

Purpose

A global trend of type 2 diabetes prevalence is rising. Preventing and managing of systemic and dental complications is crucial to decrease negative effects on glycemic control. The purpose of this paper is to estimate the efficacy of Brief Lifestyle Change in conjunction with Dental Care (Brief-LCDC) Programs to decrease glycemic level and improve periodontal status in patients with type 2 diabetes.

Design/methodology/approach

Health Center 54 conducted randomized controlled trial among 192 patients (96 intervention and 96 control) from February to August 2018. Group education for lifestyle modification, individual oral hygiene instruction and lifestyle counseling by motivational interviewing was provided to the intervention group at baseline. Motivation of lifestyle modification every month by multimedia was also provided to the intervention group. The usual program was provided to the control group. At baseline and a six-month follow-up, glycemic level and periodontal status were assessed from participants. Data were analyzed by descriptive statistic, t-test, χ2 test, Fisher’s exact test, Repeated measure ANOVA and multiple linear regression.

Findings

Glycemic level and periodontal status were lower in the intervention group than the control group at the sixth-month followed up with statistical significances. Glycemic level and periodontal status had negatively correlated to intervention group with statistically significant.

Originality/value

Brief-LCDC Program which incorporated lifestyle modification and oral health care had efficacious to decrease glycemic level and improve periodontal status in patients with type 2 diabetes. Early prevention program by Brief-LCDC Program is crucial to prevent dental complications.

Effect of non-surgical periodontal therapy on insulin resistance and insulin sensitivity among individuals with borderline diabetes: A randomized controlled trial

OBJECTIVE

To investigate the effect of non-surgical periodontal therapy on insulin resistance and sensitivity among individuals with borderline diabetes not receiving medications.

METHODS

A crossover, randomized controlled trial was conducted among participants with borderline diabetes diagnosed by a 75-g oral glucose tolerance test. Participants were randomly assigned to either an early or later intervention group. The early intervention group underwent non-surgical periodontal therapy of scaling and root planing during the first 6 months, followed by a 6-month non-intervention period. The order was reversed in the later intervention group. Primary outcomes included: fasting or post-load serum glucose and insulin, body mass index (BMI), HOMA-IR, HOMA-β, and Matsuda Index.

RESULTS

Seventy-four participants were randomized, and 71 participants completed the trial. There were no significant differences between groups in glucose and insulin concentrations during the intervention and non-intervention periods. When analyzed within groups by median-split of bleeding on probing (BOP) levels before intervention, the lower BOP group showed improved changes in BMI, HOMA-IR, HOMA-β, and Matsuda Index (P < 0.05). Further, we observed a positive correlation between baseline BOP and change in BMI (P = 0.06). Change in BMI was positively correlated with changes in HbA_1c, HOMA-IR, and HOMA-β (P < 0.05), and inversely correlated with change in Matsuda Index (P = 0.001).

CONCLUSIONS

Periodontal therapy had no significant effect on markers related to insulin and glucose metabolism among individuals with borderline diabetes. However, participants with a lower BOP (%) showed significant improvements in BMI, fasting serum insulin, HOMA-IR, HOMA-β and Matsuda Index.

CLINICAL SIGNIFICANCE

Among individuals diagnosed with borderline diabetes, those who had <37% of a lower BOP (%) showed potential improvements in BMI, fasting serum insulin, HOMA-IR, HOMA-β and Matsuda Index following non-surgical periodontal therapy.

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

BACKGROUND

Chronic inflammation is believed to be a major mechanism underlying the pathophysiology of type 2 diabetes. Periodontitis is a cause of systemic inflammation. We aimed to assess the effects of periodontal treatment on glycaemic control in people with type 2 diabetes.

METHODS

In this 12 month, single-centre, parallel-group, investigator-masked, randomised trial, we recruited patients with type 2 diabetes, moderate-to-severe periodontitis, and at least 15 teeth from four local hospitals and 15 medical or dental practices in the UK. We randomly assigned patients (1:1) using a computer-generated table to receive intensive periodontal treatment (IPT; whole mouth subgingival scaling, surgical periodontal therapy [if the participants showed good oral hygiene practice; otherwise dental cleaning again], and supportive periodontal therapy every 3 months until completion of the study) or control periodontal treatment (CPT; supra-gingival scaling and polishing at the same timepoints as in the IPT group). Treatment allocation included a process of minimisation in terms of diabetes onset, smoking status, sex, and periodontitis severity. Allocation to treatment was concealed in an opaque envelope and revealed to the clinician on the day of first treatment. With the exception of dental staff who performed the treatment and clinical examinations, all study investigators were masked to group allocation. The primary outcome was between-group difference in HbA_1c at 12 months in the intention-to-treat population. This study is registered with the ISRCTN registry, number ISRCTN83229304.

FINDINGS

Between Oct 1, 2008, and Oct 31, 2012, we randomly assigned 264 patients to IPT (n=133) or CPT (n=131), all of whom were included in the intention-to-treat population. At baseline, mean HbA_1c was 8·1% (SD 1·7) in both groups. After 12 months, unadjusted mean HbA_1c was 8·3% (SE 0·2) in the CPT group and 7·8% (0·2) in the IPT group; with adjustment for baseline HbA_1c, age, sex, ethnicity, smoking status, duration of diabetes, and BMI, HbA_1c was 0·6% (95% CI 0·3-0·9; p<0·0001) lower in the IPT group than in the CPT group. At least one adverse event was reported in 30 (23%) of 133 patients in the IPT group and 23 (18%) of 131 patients in the CPT group. Serious adverse events were reported in 11 (8%) patients in the IPT group, including one (1%) death, and 11 (8%) patients in the CPT group, including three (2%) deaths.

INTERPRETATION

Compared with CPT, IPT reduced HbA_1c in patients with type 2 diabetes and moderate-to-severe periodontitis after 12 months. These results suggest that routine oral health assessment and treatment of periodontitis could be important for effective management of type 2 diabetes.

FUNDING

Diabetes UK and UK National Institute for Health Research.

Association between periodontal condition and the development of type 2 diabetes mellitus-Results from a 15-year follow-up study

AIM

To study whether periodontal condition is associated with the development of type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

A population-based follow-up study was conducted among persons born in 1935 and living in the city of Oulu, Finland (n = 395). The baseline examinations were done during 1990-1992, and the follow-up examinations were done during 2007-2008. The data were gathered by questionnaires, laboratory tests and clinical measurements. Poisson regression models were used in the data analyses.

RESULTS

The adjusted rate ratios (RR) with 95% confidence intervals (95% CI) for the incident T2DM among subjects with 4-5 mm deep periodontal pockets (n = 98), among subjects with 6 mm deep or deeper periodontal pockets (n = 91), and among edentulous subjects (n = 118) were 1.32 (95% CI: 0.69-2.53), 1.56 (95% CI: 0.84-2.92) and 1.00 (95% CI: 0.53-1.89), respectively, compared to dentate subjects without deepened (4 mm deep or deeper) periodontal pockets (n = 88). The adjusted RR per site (the number of sites with deepened periodontal pockets as a continuous variable) was 1.02 (95% CI: 1.00-1.04).

CONCLUSIONS

Poor periodontal condition may be a predictor of the development of T2DM. However, the causality between periodontal condition and the development of T2DM remains uncertain.

Increased Oral Porphyromonas gingivalis Prevalence in Cardiovascular Patients with Uncontrolled Diabetes Mellitus

The aim of this study was to determine the correlation between periodontopathic bacteria and diabetes mellitus (DM) status in cardiovascular disease (CVD) subjects.DM is associated with the progression of periodontitis. Several epidemiological studies have suggested that periodontitis may be a risk factor for CVD. However, no study has compared the periodontal condition between well-controlled and poorly-controlled DM patients with CVD.The subjects were well-controlled (n = 73) or poorly-controlled (n = 39) DM patients with CVD. Blood examinations and dental clinical measurements, including number of teeth, probing pocket depth, bleeding on probing (BOP), and clinical attachment level (CAL) were performed. Periodontopathic bacterial existence was evaluated.Worsened CAL and BOP rate were detected in the uncontrolled DM group compared to the controlled group. We found increased salivary Porphyromonas gingivalis counts in the uncontrolled DM group compared to well-controlled DM subjects.Specific periodontopathic bacterial infection may affect DM condition in CVD patients.

25-Hydroxyvitamin D3 -enhanced PTPN2 positively regulates periodontal inflammation through the JAK/STAT pathway in human oral keratinocytes and a mouse model of type 2 diabetes mellitus

BACKGROUND AND OBJECTIVE

Periodontitis is an increasingly prevalent complication of diabetes mellitus (known as diabetes mellitus-associated periodontitis), and 25-hydroxyvitamin D₃ (25VD₃ ) was recently found to be a critical regulator of innate immunity in this disease, but the underlying mechanisms remain poorly understood. T-cell protein tyrosine phosphatase non-receptor type 2 (PTPN2) is a potential downstream protein of the 25VD₃ /vitamin D receptor pathway. The aim of this study was to investigate the regulation of PTPN2 in periodontal inflammation in diabetes mellitus-associated periodontitis.

MATERIAL AND METHODS

Porphyromonas gingivalis-infected db/db mice were treated with 25VD₃ . Their fasting blood glucose and body weight were monitored every other week, and the levels of alveolar bone loss and serum inflammatory cytokines (tumor necrosis factor-α, interferon-γ and interleukin-6) were determined at the time of killing. The effect of PTPN2 on human OKF6-TERT2 oral keratinocytes was examined through the knockout of PTPN2 using the CRISPR/Cas9 knockout plasmid. The expression levels of the PTPN2, vitamin D receptor and JAK1/STAT3 signaling proteins in the gingival epithelium and OKF6-TERT2 cells were determined through western blot and immunohistochemical analyses.

RESULTS

After 25VD₃ treatment, db/db mice exhibited alleviated serum inflammatory cytokines and alveolar bone loss, and 25VD₃ -enhanced PTPN2 expression decreased the expression of the JAK1/STAT3 signaling proteins in the gingival epithelium. Analyses of human oral keratinocytes showed that 25VD₃ increased the expression of PTPN2, which dephosphorylates protein substrates in the JAK1/STAT3 signaling pathway.

CONCLUSION

PTPN2 contributed to a decrease in periodontal inflammation in type 2 diabetes mellitus via dephosphorylate protein substrates in the JAK1/STAT3 signaling pathway after 25VD₃ treatment in human oral keratinocytes and a mouse model of type 2 diabetes mellitus. A thorough understanding of PTPN2 and its involvement in inhibiting inflammation might provide alternative therapeutic approaches for the pathogenesis and treatment of diabetes mellitus-associated periodontitis.

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

AIM

To provide an update of the review by Taylor (Journal of Clinical Periodontology, 2013, 40, S113) regarding the scientific evidence of the biological association between periodontitis and diabetes.

METHODS

Literature searches were performed using MeSH terms, keywords and title words and were published between 2012 and November 2016. All publications were screened for their relevance. The data from the articles were extracted and summarized in tables and a narrative review.

RESULTS

Small-scale molecular periodontal microbiome studies indicate a possible association between altered glucose metabolism in pre-diabetes and diabetes and changes in the periodontal microbiome, with no evidence for casual relationships. Clinical and animal studies found elevated gingival levels of IL1-β, TNF-α, IL-6, RANKL/OPG and oxygen metabolites in poorly controlled diabetes. In addition, individuals with diabetes and periodontitis exhibit high levels of circulating TNF-α, CRP and mediators of oxidative stress, and successful periodontal treatment reduces their levels.

CONCLUSIONS

The elevated pro-inflammatory factors in the gingiva of patients with poorly controlled diabetes suggest a biological pathway that may aggravate periodontitis. Some evidence suggests that the systemic inflammatory burden in periodontitis has the potential to affect diabetes control, but no studies addressed the impact of successful periodontal therapy on the pathophysiological mechanisms involved in systemic complications of diabetes.

The effect of dental bleaching on pulpal tissue response in a diabetic animal model: a study of immunoregulatory cytokines

AIM

To evaluate the influence of tooth bleaching on immunoregulatory cytokines production (IL-6, Tumour necrosis factor (TNF)-α and IL-17) in the pulp tissue of normoglycaemic and diabetic rats.

METHODOLOGY

Twenty-eight rats were divided into normoglycaemic and diabetic rats (n = 14). Diabetes mellitus (DM) was induced with a single dose of alloxan diluted in citrate buffer via intramuscular injection. After DM confirmation, all rats were sedated and tooth bleaching was performed using 35% hydrogen peroxide on the right maxillary molars for 30 min. Left molars were used as controls. Bleaching resulted in four hemimaxillae groups: normoglycaemic (N), N-bleached (NBle), diabetic (D) and D-bleached (DBle). After 2 and 30 days, rats were euthanized and hemimaxillae processed for analysis by haematoxylin and eosin and immunohistochemistry. Results within and between animals were submitted to Wilcoxon signed-rank and Mann-Whitney tests (P < 0.05).

RESULTS

At 2 days, the NBle group had mild, and the DBle had severe inflammatory infiltration in the pulpal tissue (P < 0.05). TNF-α and IL-6 cytokines were associated with increased immunolabelling in the bleached groups compared to nonbleached (P < 0.05). However, IL-17 had increased immunolabelling in the NBle compared to the N and DBle group (P < 0.05). At 30 days, reactionary dentine was observed in the coronal pulp of all bleached teeth and no inflammation was present (P > 0.05). TNF-α cytokines had increased immunolabelling in the DBle group compared to the D group (P < 0.05). However, for IL-6 and IL-17, no difference was observed in this period (P > 0.05).

CONCLUSIONS

Tooth bleaching increased IL-6 and TNF-α in the pulp tissue regardless of diabetes mellitus; however, diabetic rats had higher TNF-α levels for longer periods. Tooth bleaching influenced the increase in IL-17 in the early periods in normoglycaemic rats.

Metformin in combination with rosiglitazone contribute to the increased serum adiponectin levels in people with type 2 diabetes mellitus

To evaluate how metformin plus rosiglitazone affect serum adiponectin levels in people suffering from type 2 diabetes mellitus (T2DM), 240 patients having T2DM were selected in this cohort study. Included subjects were randomly and equally separated into three subsets: i) Group A (rosiglitazone group); ii) group B (metformin group); and iii) group C (rosiglitazone + metformin group). Furthermore, meta-analysis of previous studies was performed by searching the general search engines and bibliographic databases. Compared with before treatment, the serum amount of adiponectin grew considerably in the three groups after treatment, and the levels in the group C was much greater than those of groups A and B (all P<0.05). Corresponding meta-analysis results suggested post-treatment serum adiponectin level to be greater than pretreatment level in T2DM patients (P<0.001). Further subgroup analyses indicated that combination therapy of metformin and rosiglitazone may increase the amount of serum adiponectin in T2DM sufferers among the majority subgroups (all P<0.05). The combination of metformin and rosiglitazone treatment increased serum adiponectin levels, suggesting that metformin plus rosiglitazone therapy is a suitable choice to treat T2DM.

Effects of nonsurgical periodontal therapy in patients with moderately controlled type 2 diabetes mellitus and chronic periodontitis in Nepalese population

Objectives

Despite several investigations, evidence is still controversial regarding the effect of periodontal treatment on diabetes. This study evaluates and compares the effect on glycemic control and periodontal status with or without nonsurgical periodontal therapy in patients with type 2 diabetes mellitus and chronic periodontitis in a Nepalese population.

Materials and methods

A total of 82 patients attending the diabetes clinic and fulfilling enrollment criteria with moderate to severe periodontitis were selected. They were assigned in an alternative sequence, into test and control group. Both groups were instructed to continue with their medical treatment without modifications. Scaling and root surface debridement were performed in the test group whereas the control group received oral hygiene instructions with no treatment during the 3-month study period.

Results

There were 41 participants in each group with the mean age of 50.66±7.70 and 53.80±9.16 years, average diabetes duration of 6.32±4.21 and 6.24±4.00 years, mean body mass index of 24.78±1.85 and 24.6±1.79 kg/m², and glycated hemoglobin (HbA1c) level of 6.71±0.50% and 6.80±0.45%, in the test and control group, respectively. After 3 months, there was significant reduction in HbA1c levels in the test group compared to the control group (p=0.029). Clinical periodontal parameters of gingival index, probing depth (PD), and clinical attachment level (CAL) significantly improved in the test group (p<0.001) with PD reduction by 0.9 mm and gain in CAL by 0.3 mm compared to the control group (p>0.001) who showed an increase by 0.05 mm.

Conclusion

This study showed that nonsurgical periodontal therapy may have a beneficial effect on HbA1c level in moderately controlled type 2 diabetic patients.

Association of circulating leptin and adiponectin with periodontitis: a systematic review and meta-analysis

BACKGROUND

This study aimed to assess the difference in serum levels of leptin and adiponectin in patients with periodontitis and in periodontally healthy individuals and evaluate the changes in circulating leptin and adiponectin after periodontal therapy. Leptin and adiponectin are the most generally studied adipokines that function as inflammatory cytokines. Although the association between periodontitis and serum levels of leptin and adiponectin has been studied extensively, the results were not consistent.

METHODS

A systematic search of the Pubmed, Embase, Web of Science, and Cochrane Library up to September 2016 was conducted. The studies were screened and selected by two writers according to the specific eligibility criteria. The quality of included cross-sectional studies was assessed using the quality assessment form recommended by the Agency for Healthcare Research and Quality and Methodological Index for Nonrandomized Studies. The meta-analyses were conducted using the STATA 12.0 software.

RESULTS

A total of 399 manuscripts were yielded and 25 studies were included in the present meta-analysis. Significantly elevated serum levels of leptin and decreased serum levels of adiponectin in patients with periodontitis were observed in the subgroup analysis of body mass index (BMI) <30. The overall and subgroup analyses showed no significant change in the serum levels of leptin in patients with periodontitis after periodontal treatment. The subgroup analysis of systemically healthy patients showed no significant change in serum levels of adiponectin in patients with periodontitis after periodontal treatment.

CONCLUSIONS

The present meta-analysis supported elevated serum levels of leptin and decreased serum levels of adiponectin in patients with periodontitis compared with controls in the BMI <30 population. In systemically healthy patients with periodontitis, serum levels of leptin and adiponectin do not significantly change after periodontal treatment.