Correlation between periodontal disease management and metabolic control of type 2 diabetes mellitus. A systematic literature review

Effectiveness of periodontal treatment to improve glycemic control: an umbrella review

AIM

The aim of the present umbrella review was to systematically assess existing evidence on the effect of non-surgical periodontal therapy, both per se' and with adjuvants, on glycemic control in patients with type 2 diabetes and periodontitis and to combine quantitative data with a meta-analysis.

MATERIALS AND METHODS

A detailed study protocol was registered on PROSPERO (CRD42021222279). Four electronic databases (Medline via Pubmed, EMBASE, Cochrane Database of Systematic Reviews and Scielo) were searched independently and in duplicate to identify potentially eligible systematic reviews up to March 2022. Two pre-calibrated independent reviewers performed study selection, data extraction and quality assessment with two checklists (AMSTAR 2 and PRISMA). Moreover, general characteristics of primary studies included in each systematic review were abstracted, and JADAD scale was used to assess the risk of bias for included randomized controlled trials. Data from the individual studies included in each meta-analysis were analyzed, using both fixed and random effect model. The statistical heterogeneity was calculated using the Q test and the I² index. The publication bias was evaluated using a funnel plot and Egger's linear regression method.

RESULTS

Sixteen systematic reviews, published between 2010 and 2021, were included for qualitative synthesis. From these systematic reviews, a total of 27 studies were included in the meta-analysis: all of them were randomized clinical trials, except 1 controlled clinical study. A statistically significant mean difference of - 0.49% and of - 0.38% HbA1c reductions was seen respectively at 3- and 6-month post-treatment, favoring the treatment group (non-surgical periodontal therapy alone) compared to the control group (no treatment). The effect of periodontal treatment with the adjunctive use of antibiotics or laser on the glycemic control was not statistically significant compared to non-surgical periodontal therapy alone.

CONCLUSIONS

The findings of the present study, within its limitations, indicated that non-surgical treatment of periodontitis is an efficacious therapy for improving the glycemic control in type 2 diabetes mellitus patients, both at 3- and 6-month follow-up.

Study protocol for periodontal tissue regeneration with a mixture of autologous adipose-derived stem cells and platelet rich plasma: A multicenter, randomized, open-label clinical trial

Introduction

Adipose-derived stem cells (ASCs) secrete various growth factors to promote wound healing and to regenerate various tissues, such as bone, cartilage, and fat tissue. Subcutaneous adipose tissue is a considerable cell source in clinical practice and can be collected relatively easily and safely under local anesthesia. Moreover, platelet-rich plasma (PRP), a plasma component containing many platelets purified by centrifuging the collected blood, also promotes wound healing. PRP can be easily gelled and is therefore attracting attention as a scaffolding material for transplanted cells. The usefulness of a mixture of ASCs and PRP for periodontal tissue regeneration has been in vitro demonstrated in our previous study. The aim of this study is to present the protocol of translation of tissue regeneration with ASCs and PRP into practical use, evaluating its efficacy.

Methods

This study is a multicenter, randomized, open-label comparative clinical trial. Fifteen patients will be randomly assigned to the treatment with mixture of ASCs and PRP or enamel matrix derivate administration into periodontal tissue defects. Increase in height of new alveolar bone in the transplanted area will be evaluated. The evaluation will be performed using dental radiographs after 36 weeks of transplantation. Occurrence of adverse events will be evaluated as secondary outcome.

Results

This clinical study was initiated after meeting the regulations to be complied with, including ethical review and regulatory notifications.

Conclusions

If effective, this cell therapy using autologous mesenchymal stem cells can represent a useful medical technology for regeneration of periodontal defects.

An in vitro study on the degradation of multispecies biofilm of periodontitis-related microorganisms by bovine trypsin

To investigate the degradation effect of bovine trypsin on multispecies biofilm of periodontitis-related bacteria and to provide an experimental reference for exploring new methods for controlling biofilms of periodontitis-related microorganisms, the multispecies biofilm of periodontitis-related microorganisms was established. Standard strains of Porphyromonas gingivalis, Fusobacterium nucleatum subsp. polymorpha, Actinomyces viscosus, and Aggregatibacter actinomycetemcomitans were co-cultured to form the biofilm. The experimental groups were treated with bovine trypsin, distilled water was applied as the blank control group, and phosphate saline buffer (pH = 7.4) as the negative control group. Morphological observation and quantitative analysis of extracellular polymeric substances (EPS), live bacteria, and dead bacteria were conducted using a laser confocal microscope. The morphological changes of EPS and bacteria were also observed using a scanning electron microscope. The results of morphological observations of modeling were as follows. EPS aggregated as agglomerates, and bacteria flora were wrapped by them, showing a three-dimensional network structure, and channel-like structures were inside the biofilm. Live bacteria were distributed on the surface of the EPS or embedded in them, dead bacteria aggregated between live flora and the bottom layer of biofilms. After being treated with bovine trypsin, the three-dimensional network structure and the channel-like structure disappeared, and the EPS and live and dead bacteria decreased. Quantitative analysis results are as follows. When biofilm was treated for 30 s, 1 min, and 3 min, the minimum effective concentrations of bovine trypsin to reduce EPS were 2 mg/ml (P < 0.05), 0.5 mg/ml (P < 0.05), and 0.25 mg/ml (P < 0.05), respectively. The minimum effective concentrations of bovine trypsin to reduce the live or dead bacteria were 2 mg/ml (P < 0.05), 0.5 mg/ml (P < 0.05), and 0.5 mg/ml (P < 0.05), respectively. There was no significant difference in the ratio of live/dead bacteria after the biofilm was treated for 30 s with bovine trypsin at the concentration of 0.25, 0.5, 1, and 2 mg/ml (P > 0.05), and the minimum effective concentration to reduce the ratio of live bacteria/dead bacteria was 0.25 mg/ml (P < 0.05) after treatment for 1 min and 3 min. Therefore, bovine trypsin can destroy biofilm structure, disperse biofilm and bacteria flora, and reduce the EPS and bacterial biomass, which are positively correlated with the application time and concentration.

Diagnostic value of microbiome biomarkers of the periodonite microbiome in patients with the association of chronic periodontitis and diabetes mellitus type 2

The place of high-tech methods of molecular biology in clinical laboratory diagnostics of various diseases and the development of a system of biomarkers as an important component of diagnostic research is currently attracting the closest attention of the scientific community. In this paper, an attempt is made to use high-tech metagenomic analysis to solve problems that arise due to the high frequency of association of periodontal diseases with systemic pathology, in particular, with type 2 diabetes mellitus. The aim of the study was to determine the taxonomic and metabolic features of the microbiome of periodontal tissues in periodontal diseases associated with type 2 diabetes mellitus, as a model of the ratio of local and systemic effects of periodontal pathogenic bacteria. The study included 16S shotgun sequencing of bacterial DNA as part of biological material from periodontal pockets/dentoalveolar furrows of 46 people - 15 patients with chronic periodontitis associated with type 2 diabetes mellitus, 15 patients with chronic periodontitis unrelated to systemic pathology, as well as 16 healthy people in the control group, followed by bioinformatic processing of the data obtained. The obtained data allowed us to establish the taxonomic features of the periodontal microbiome in the association of chronic periodontitis with type 2 diabetes mellitus, which included the predominance of representatives of the families Prevotellaceae and Spirochaetaceae in its composition. The features of metabolic processes in periodontal tissues with the participation of the microbiome were also revealed, which consisted in an increase in the exchange of cysteine and methionine against the background of a decrease in the metabolism of pyrimidine, methane, sphingolipids, and the synthesis of fatty acids, which are of diagnostic value in assessing the condition of patients with type 2 diabetes mellitus.

Drift of the Subgingival Periodontal Microbiome during Chronic Periodontitis in Type 2 Diabetes Mellitus Patients

Since periodontitis and type 2 diabetes mellitus are complex diseases, a thorough understanding of their pathogenesis requires knowing the relationship of these pathologies with other disorders and environmental factors. In this study, the representability of the subgingival periodontal microbiome of 46 subjects was studied by 16S rRNA gene sequencing and shotgun sequencing of pooled samples. We examined 15 patients with chronic periodontitis (CP), 15 patients with chronic periodontitis associated with type 2 diabetes mellitus (CPT2DM), and 16 healthy subjects (Control). The severity of generalized chronic periodontitis in both periodontitis groups of patients (CP and CPT2DM) was moderate (stage II). The male to female ratios were approximately equal in each group (22 males and 24 females); the average age of the subjects was 53.9 ± 7.3 and 54.3 ± 7.2 years, respectively. The presence of overweight patients (Body Mass Index (BMI) 30–34.9 kg/m²) and patients with class 1–2 obesity (BMI 35–45.9 kg/m²) was significantly higher in the CPT2DM group than in patients having only chronic periodontitis or in the Control group. However, there was no statistically significant difference in all clinical indices between the CP and CPT2DM groups. An analysis of the metagenomic data revealed that the alpha diversity in the CPT2DM group was increased compared to that in the CP and Control groups. The microbiome biomarkers associated with experimental groups were evaluated. In both groups of patients with periodontitis, the relative abundance of Porphyromonadaceae was increased compared to that in the Control group. The CPT2DM group was characterized by a lower relative abundance of Streptococcaceae/Pasteurellaceae and a higher abundance of Leptotrichiaceae compared to those in the CP and Control groups. Furthermore, the CP and CPT2DM groups differed in terms of the relative abundance of Veillonellaceae (which was decreased in the CPT2DM group compared to CP) and Neisseriaceae (which was increased in the CPT2DM group compared to CP). In addition, differences in bacterial content were identified by a combination of shotgun sequencing of pooled samples and genome-resolved metagenomics. The results indicate that there are subgingival microbiome-specific features in patients with chronic periodontitis associated with type 2 diabetes mellitus.

Does Nonsurgical Periodontal Treatment Improve Systemic Health?

Clinicians frequently stress the importance of maintaining good oral health for multiple reasons, including its link to systemic health. Because periodontal treatment reduces inflammation in oral tissues, some hypothesize it may positively affect systemic outcomes by reducing inflammation in the body. A significant number of systematic reviews (SRs) and meta-analyses (MAs) have evaluated the effect of periodontal treatment on systemic outcomes. However, inconsistent findings and questionable methodological rigor make drawing conclusions difficult. We conducted a systematic review of reviews that studied the effect of nonsurgical periodontal treatment on systemic disease outcomes. We report on outcomes evaluated, categorizing them as biomarkers, and surrogate or clinical endpoints. In addition, we used A MeaSurement Tool to Access systematic Reviews 2 (AMSTAR 2) to evaluate the methodological quality of the reviews. Of the 52 studies included in our review, 21 focused on diabetes, 15 on adverse birth outcomes, 8 on cardiovascular disease, 3 each on obesity and rheumatoid arthritis, and 2 on chronic kidney disease. Across all studies, surrogate endpoints predominated as outcomes, followed by biomarkers and, rarely, actual disease endpoints. Ninety-two percent of studies had "low" or "critically low" AMSTAR 2 confidence ratings. Criteria not met most frequently included advance registration of the protocol, justification for excluding individual studies, risk of bias from individual studies being included in the review, and appropriateness of meta-analytical methods. There is a dearth of robust evidence on whether nonsurgical periodontal treatment improves systemic disease outcomes. Future reviews should adhere more closely to methodological guidelines for conducting and reporting SRs/MAs than has been the case to date. Beyond improved reviews, additional rigorous research on whether periodontal treatment affects systemic health is needed. We highlight the potential of large-scale databases containing matched medical and dental record data to inform and complement future clinical research studying the effect of periodontal treatment on systemic outcomes.

Adjunctive subantimicrobial dose doxycycline in the treatment of chronic periodontitis in type 2 diabetic patients: A unique combination therapy

Background/Aim: To evaluate the effectiveness of combination therapy including subantimicrobial dose doxycycline (SDD) and locally delivered doxycycline (LD) as adjuncts to scaling and root planing (SRP) in the treatment of chronic periodontitis in patients with type 2 diabetes mellitus (T2DM). Material and Methods: Forty patients with controlled T2DM (HbA1c ≤7%) and chronic periodontitis were selected. They were randomly divided into two groups, twenty patients each: Test group (TG, n=20) patients was treated with combination therapy of full mouth SRP, LD gel 10% and SDD 20 mg twice daily for 6 months. Control group (CG, n=20) patients was treated with full mouth SRP only. The periodontal parameters were recorded at baseline, 3, 6 and 9 months and included periodontal probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP). Gingival crevicular fluid (GCF) samples were collected and a quantitative measurement of matrix metalloproteinase-8 (MMP-8) was carried out by using Enzyme-Linked Immunosorbent Assay (ELIZA) at baseline, 3, 6 and 9 months. Results: Statistically significant reduction in all clinical parameters (PPD, CAL, and BOP) was observed at TG over CG at 3, 6, and 9 months (p<0.05). Moreover, combination therapy provided significant reductions in the amount of GCF MMP-8 for the TG compared to CG at 3, 6, and 9 months evaluation period (p<0.05). Conclusions: Combination therapy including SRP, SDD, and LD, provided significantly greater clinical benefits than SRP alone in the treatment of chronic periodontitis in patients with controlled T2DM.

The effect of triclosan on posttranslational modification of proteins through citrullination and carbamylation

OBJECTIVES

The aim of this study was evaluate the effect of triclosan on citrullination and carbamylation, two important protein posttranslational modifications associated with inflammatory conditions such as periodontitis and rheumatoid arthritis.

MATERIALS AND METHODS

A range of triclosan concentrations were incubated in the presence of appropriate substrates used for the generation of either citrullinated or carbamylated proteins. The effect of triclosan on protein citrullination and carbamylation in macrophages was also assessed.

RESULTS

Citrullination and carbamylation were both significantly decreased by triclosan at concentrations six times lower than the 0.3% triclosan approved by the FDA to use in mouthwash and toothpaste. When macrophages were exposed to triclosan, carbamylation was significantly deceased (p = 0.01), and while citrullination also decreased, this reduction was not statistically significant (p = 0.06).

CONCLUSION

Triclosan reduced the generation of protein citrullination and carbamylation in vitro.

CLINICAL RELEVANCE

Triclosan may be useful as an adjunct therapy in the management of inflammatory periodontal diseases and help to reduce posttranslational protein modification citrullination and carbamylation) in these tissues.

Integrated metagenomic data analysis demonstrates that a loss of diversity in oral microbiota is associated with periodontitis

Background

Periodontitis is an inflammatory disease affecting the tissues supporting teeth (periodontium). Integrative analysis of metagenomic samples from multiple periodontitis studies is a powerful way to examine microbiota diversity and interactions within host oral cavity.

Methods

A total of 43 subjects were recruited to participate in two previous studies profiling the microbial community of human subgingival plaque samples using shotgun metagenomic sequencing. We integrated metagenomic sequence data from those two studies, including six healthy controls, 14 sites representative of stable periodontitis, 16 sites representative of progressing periodontitis, and seven periodontal sites of unknown status. We applied phylogenetic diversity, differential abundance, and network analyses, as well as clustering, to the integrated dataset to compare microbiological community profiles among the different disease states.

Results

We found alpha-diversity, i.e., mean species diversity in sites or habitats at a local scale, to be the single strongest predictor of subjects’ periodontitis status (P < 0.011). More specifically, healthy subjects had the highest alpha-diversity, while subjects with stable sites had the lowest alpha-diversity. From these results, we developed an alpha-diversity logistic model-based naive classifier able to perfectly predict the disease status of the seven subjects with unknown periodontal status (not used in training). Phylogenetic profiling resulted in the discovery of nine marker microbes, and these species are able to differentiate between stable and progressing periodontitis, achieving an accuracy of 94.4%. Finally, we found that the reduction of negatively correlated species is a notable signature of disease progression.

Conclusions

Our results consistently show a strong association between the loss of oral microbiota diversity and the progression of periodontitis, suggesting that metagenomics sequencing and phylogenetic profiling are predictive of early periodontitis, leading to potential therapeutic intervention. Our results also support a keystone pathogen-mediated polymicrobial synergy and dysbiosis (PSD) model to explain the etiology of periodontitis. Apart from P. gingivalis, we identified three additional keystone species potentially mediating the progression of periodontitis progression based on pathogenic characteristics similar to those of known keystone pathogens.