Submitted:
11 April 2024
Posted:
15 April 2024
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Abstract
Keywords:
Introduction
Type 1 Diabetes Mellitus
Clinical Phenotype Of T1DM
Pathogenesis of Type 1 Diabetes Mellitus
Preclinical and Clinical Evidence
Type 1 Diabetes Mellitus and Oral Microbiota
| References | Type of study | Methodology | Types of Samples & Microbiological Analysis | Results | Conclusions |
|---|---|---|---|---|---|
|
Arangann et al., 2013 |
Comparative case-control clinical study | ● Dental and medical examination ● Subgingival plaque sampling from permanent first molars |
Polymerase chain reaction assay for 6S rRNA gene detection | ● No significant statistical difference regarding the prevalence of P. Gingivalis, T. Denticola, and A. actinomycetemcomitans among T1DM and healthy children ● T. Forsythia was less prevalent in diabetic children compared to healthy children |
Similar microbiologic findings in T1DM patients and healthy children |
| Carelli et al., 2023 | Cross-sectional study | ● HbA1c ● Continuous glucose monitoring metrics (GCM) of glycemic control and glucose variability ● Saliva sampling |
● DNA extraction ● Bacterial culture-based analysis ● PCR |
● Actinomyces spp., A. actinomycetemcomitans, P. intermedia, and Lactobacillus spp. in all subjects ● S. mutans present in approximately 49.4% of samples ● Higher presence of S. mutans and Veillonella spp. in subjects with poorer glycemic control (HbA1c, %TIR, %TAR). ● Association observed even after adjusting for age, sex, and hygiene habits ● Virtuous habits (toothbrush changes, professional oral hygiene) negatively correlated with T. forsythia, T. denticola, and P. gingivalis |
Importance of glycemic control and regular oral hygiene in preventing oral microbiota linked to dental and periodontal issues in individuals with T1DM since childhood |
| Castrillon CA et al., 2015 | Comparative case-control clinical study | ● Periodontal examination ● Subgingival plaque samples from the three deepest sites |
DNA extraction by silica |
● Diabetic patients showed significantly higher levels of periodontal attachment loss than non-diabetic patients ● A. actinomycetemcomitans was more prevalent in diabetic patients with periodontitis compared to systemically healthy patients without periodontitis ● P. gingivalis was associated with periodontitis in non-diabetic patients, while A. actinomycetemcomitans was linked to periodontitis in diabetic patients |
● Subgingival microbiota differences exist between diabetic and non-diabetic patients ● P.gingivalis and A. actinomycetemcomitans are associated with periodontitis in non-diabetic and diabetic patients, respectively |
| Chakraborty et al., 2021 | Cross-sectional study | Gingival plaque sampling | Culture based microbial identification and biofilm assay | ● Higher microbial diversity in diabetes with periodontal disease group ● S. warneri found only in diabetes with periodontal disease group ● Higher incidence of S. vitulinus, S. sanguinis, and P. aeruginosa in diabetes with periodontal disease group ● Strong positive correlation between poor glycemic control and biofilm formation in both diabetes with and without periodontal disease |
T1DM children with worse glycemic control, especially with periodontitis, showed increased biofilm formation and microbial diversity |
| Duque et al., 2016 | Comparative case-control clinical study | ● Periodontal status ● Glycemic and lipid profiles ● Subgingival plaque samples from periodontal sites ● Blood samples for IL-1b, TNF- and IL-6 |
● PCR ● ELISA |
● Similar periodontal conditions in T1DM and non-diabetic patients ● Higher lipid parameters in DM group among patients with gingivitis ● Increased prevalence of C. sputigena and C. ochracea in periodontal sites of DM children ● Limited detection of "Red complex" bacteria in both groups ● Frequent occurrence of F. nucleatum and C. rectus ● Comparable levels of TNF-α and IL-6 in both groups |
● Gingivitis in type 1 diabetes children associated with C. sputigena and C. ochracea ● Overall periodontal health and inflammatory markers similar between the two groups |
|
Gregorczyk-Maga et al., 2023 |
Pilot study | Samples from the mucosa of the buccal and soft palate, tongue, palatal and buccal dental surfaces, and gingival pockets in adult patients with type 1 diabetes mellitus undergoing treatment with insulin pump therapy |
Microbiologival cultures with dilution method or qualitative culture method |
● Dominant oral microbiota included Streptococcus and Neisseria ● Low incidence of cariogenic S. mutans, Lactobacillus, and periodontal pathogens like Prevotella ● Significant differences in CFU counts observed between mucosal and dental surface sites for all strains, Gram-positive, Staphylococci, Streptococci, and Streptococcus oralis strain ● Candida species were rare ● Mucosal sites exhibited lower diversity and bacterial counts |
● Adult T1DM patients treated with insulin pomp, distinct differences in oral microbiota were observed in specific niches ● Identified optimal sampling sites for oral microflora: buccal and palatal mucosa, dental surface, and gingival pockets |
| Jensen et al., 2020 | Cross-sectional study | ● Dental and periodontal examination ● Buccal and gingival bacterial sampling |
16S rRNA sequencing |
● 49% had early markers of periodontal disease ● Positive correlations between HbA1c and plaque index, gingival index, bleeding on probing, and periodontal pocket depth >3 mm ● A 1% increase in HbA1c associated with a 25% increase in bleeding on probing and a 54% increase in sites with pocket depth >3 mm ● Higher HbA1c independently related to increased phylogenetic alpha diversity and compositional variation in gingival microbiota ● Brushing frequency, plaque index, and gingival index affected microbiota composition, independent of HbA1c |
● Relationship between less favorable glycemic control and increased early markers of periodontal disease ● Glycemic control is linked to the complexity and richness of plaque microbiota, with diversity increasing as HbA1c levels rise |
| Kumar et al., 2012 | Comparative parallel group clinical study | ● Dental and periodontal examination ● Sub gingival plaque sampling |
Bacterial cultures with ‘standard loop semiquantitative method’. |
No statistical difference between the three groups ( insulin-dependent, non-insulin dependent diabetics and non-diabetic periodontitis patients) | The microbial flora of the periodontitis patients is not influenced by their diabetic status |
| Lalla et al., 2006 | Comparative case-control clinical study | ● Periodontal examination ● Blood samples ● Subgingival plaque sampling |
● DNA–DNA hybridization ● Cytokine multiplex analyses ● Checkboard immunoblotting |
● Elevated levels of E. nodatum in diabetic patients among the i ● IgG titres showed no significant differences between diabetic and non-diabetic groups, both before and after adjustments for microbial load ● Diabetic patients exhibited higher serum levels of soluble E-selectin, vascular cell adhesion molecule-1, and adiponectin ● Diabetic patients had lower levels of plasminogen activator inhibitor-1 |
● Controlling for the severity of periodontal disease, both T1DM patients and non-diabetic controls displayed comparable subgingival infection patterns ● Serum antibody responses were similar between diabetic and non-diabetic groups after adjusting for periodontal disease severity |
| Mahalakshmi et al., 2019 | Comparative case-control clinical study | ● Periodontal examination ● Subgingival plaque sampling |
PCR | No statistically significant difference in the prevalence of C. rectus, E. corrodens, P. intermedia, P. nigrescens between type 1 diabetic and healthy children |
Negative correlation of T1DM with periodontitis in association to 4 periopathogenic bacteria |
| Mandell et al., 1992 | Cross-sectional study | ● Periodontal examination ● Subgingival plaque sampling |
Bacterial cultures | ● Elevated levels of periodontal pathogens at diseased sites, including P. intermedia, P. melaninogenica spp., and others ● Higher prevalence of P. intermedia and melaninogenica spp., and Campylobacter rectus at diseased sites ● Significantly higher percentage of P. intermedia at sites with deep pockets and attachment loss |
Correlation observed between periodontal disease in insulin dependent diabetes patients (T1DM) and increased levels of specific pathogens |
| Mashimo et al., 1982 | Cross-sectional study | ● Periodontal examination ● Subgingival plaque sampling |
● Bacterial cultures ● Immunofluorescence microscopy ● ELISA |
● Predominance of Capnocytophaga and anaerobic vibrios in cultivable microflora of individuals with insulin-dependent diabetes and periodontitis ● Presence of A. actinomycetemcomitans in some individuals with insulin-dependent diabetes (T1DM) ● Distinct subgingival flora in individuals with insulin-dependent diabetes and periodontitis compared to patients periodontitis ● Periodontitis lesions in nondiabetic adults often contain black-pigmented Bacteroides such as gingivalis or melaninogenicus subspecies intermedius ● Antibiotic susceptibility patterns suggest the potential effectiveness of penicillin, tetracycline, or its analogs like minocycline against the predominant cultivable microflora in periodontal lesions of individuals with with insulin-dependent diabetes (T1DM) |
The subgingival organisms identified in periodontal lesions of individuals with insulin-dependent diabetes (T1DM) exhibit quantitative distinctions from those observed in cases of periodontitis |
| Moskovitz et al., 2021 | Comparative case-control clinical study | ● Periodontal examination ● Unstimulated saliva sampling |
● DNA extraction ● qPCR ● 16S rRNA library preparation ● Sequencing |
● Identified 105 genera and 211 species in salivary microbiome ● Abondant genera: Streptococcus, Prevotella, Veillonella, Haemophilus, Neisseria ● Streptococcus more abundant in type 1 diabetes children ● Catonella, Fusobacterium, Mogibacterium differed between healthy and T1DM subjects ● Porphyromonas and Mogibacterium correlated with salivary parameters |
● Salivary microbiome analysis revealed unique taxa in T1DM children ● Association between certain salivary genera and gut microbiome in T1DM patients |
| Olczak-Kowalczyk et al., 2015 | Comparative parallel group clinical study | ● General medical examination ● Periodontal examination ● Oral bacterial swabs |
● Bacterial cultures ● Tests for enzymic profiles |
● Candida spp. detected in healthy and nephrotic syndrome/T1DM patients ● Oral candidiasis found in nephrotic syndrome and T1DM patients ● Gingivitis is more common in nephrotic syndrome/T1DM patients ● In diabetes, severity linked to blood glucose and glycated haemoglobin >8% |
● Gingivitis mainly caused by poor hygiene ● Severity associated with age, lipid disorders, and increased body mass ● Candida spp. may worsen plaque-related gingivitis in diabetes and immunosuppressed patients |
| Pachoński et al., 2021 | Comparative case-control clinical study | Oral bacterial swabs | ● Bacterial cultures ● Sets of reagents for species identification |
● Statistically significant differences in the total number of isolated microorganisms were found between poorly controlled T1DM patients and healthy controls ● Statistically significant differences in the total number of isolated microorganisms were found between well controlled T1DM patients and healthy controls ● No statistically significant differences were observed in the number of isolated microorganisms between poorly and well controlled T1DM patients |
Oral microbiome in T1DM children differs quantitatively and qualitatively from healthy children |
| Sakalauskiene et al., 2014 | Comparative case-control clinical study | ● Periodontal and radiographic examination ● Blood samples ● Supra and subgingival plaque sampling |
● Bacterial cultures ● Molecular genetic assay |
● F. nucleatum, Capnocytophaga species, and E. corrodens were the most frequently identified bacteria in dental plaque samples ( ● A. actinomycetemcomitans was 40.7% less frequently identified in the diabetes type 1 group compared to the healthy group ● Periodontal disease was more pronounced IN T1DM patients ● The prevalence of periodontitis significantly increased in subjects with poorer metabolic control |
The presence of two periodontal pathogens, F. nucleatum and Capnocytophaga spp., showed the strongest relationship with poorer metabolic control in T1DM patients and all clinical parameters of periodontal pathology |
| Sandholm et al., 1989 | Comparative case-control clinical study | Subgingival plaque sampling | ● Bacterial cultures ● Microscopic observation |
● Significantly more Gram-negative rods and fusiforms, total Gram-negative bacteria, and Rhodes-stained straight and curved rods in patients compared to controls ● Controls have significantly more Gram-positive and Gram-negative cocci, total Gram-positive bacteria, and Rhodes-stained fusiforms than in insulin dependent diabetes patients ● Controls exhibit higher percentages of spirochetes and flagellated bacteria compared to in insulin dependent diabetes patients ● The distribution of morphotypes is not influenced by age, duration of diabetes, or metabolic control measured by HbA1c scores in patients |
Diabetes patients exhibited lower proportions of cocci and total Gram-positive bacteria but higher proportions of periodontally more pathogenic forms, Gram-negative rods, and total Gram-negative bacteria compared to controls even if they had comparable hygiene |
| Sastrowijoto et al., 1989 | Comparative case-control clinical study | ● General medical examination ● Periodontal examination ● Subgingival plaque sampling |
Bacterial cultures and use of isolation and identification media | ● No significant difference in periodontal condition between patients in the poorly and well controlled T1DM patients ● Age of diabetic patients and duration of diabetes mellitus did not influence periodontal parameters ● Proportionally high percentages of cultivable bacteria were found in diseased periodontal pockets |
● Metabolic control had no direct effect on the periodontium ● The role of Capnocytophaga species in the pathogenesis of infectious periodontal disease in T1DM patients might be overestimated |
| Sbordone et al., 1995 | Comparative case-control clinical study in siblings | ● General medical examination ● Periodontal examination ● Subgingival plaque sampling |
● Bacterial cultures and use of isolation and identification media ● Biochemical tests |
No significant differences detected in any clinical and microbiological data | Limited distinctions were noted between individuals with T1DM and their healthy counterparts within this population |
| Selway et al., 2023 | Post-hoc cross-sectional study | ● Periodontal examination ● Medical and dental history ● Gingival swab samples |
16S rRNA gene sequencing |
● Children with a family history of dyslipidemia exhibited distinct bacterial diversity and composition compared to those without a family history ● Differences were not observed in children with periodontal risk, irrespective of a family history of hyperlipidemia |
In children diagnosed with T1DM, findings highlight an association between oral microbiota and two distinct exposure variables: familial history of hyperlipidemia and periodontal risk factors |
| Singh-Hüsgen et al., 2016 | Cross-sectional study | ● Periodontal and dental examination ● Medical examination ● Supra and subgingival plaque sampling |
PCR | ● A statistically significant difference in the decayed, missing, and filled surfaces (dmfs) index value was observed among the three groups ( healthy, type 1 diabetes and phenylketonuria group) ● When comparing diabetics to healthy children, a small but statistically significant difference in the Periodontal Index (PBI) score was revealed ● Statistically significant differences were found in the counts of Lactobacillus , Leptotrichia , and P. gingivalis among the three groups |
Diabetic children displayed a lower caries experience in their primary dentition but were found to have a slightly higher risk of developing periodontal disease |
| Sjdödin et al., 2012 | Comparative case-control clinical study | ● Periodontal, dental aand radiographic examination and history ● Medical examination and history ● Subgingival plaque sampling |
Checkboard DNA-DNA hybridization | ● Periodontal health indicators, including probing pocket depths and marginal bone loss, were generally favorable in all patients ● The distribution of various microbiological species was similar between the study and control groups |
Periodontal and microbiological status in young adults with insulin dependent diabetes (T1DM) does not differ significantly from that of healthy controls |
| Author | Type of study | Methodology | Types of Samples & Immune Analysis | Results | Conclusions |
|---|---|---|---|---|---|
| Aral et al., 2017 |
Prospective case-control study |
32 T1DM patients at diagnosis, and age- and gender-matched 36 systemically healthy children with (G) and without (H) gingivitis were enrolled for periodontal exam and oxidative stress markers. The diabetic patients who took insulin therapy (1.5 units/kg/day totally) and periodontal treatment (oral hygiene education with professional scaling) were re-evaluated after 3 months. |
Total antioxidant status (Pachonski et al.), total oxidant status (TOS), and oxidative stress index (OSI) were measured in saliva, GCF and serum. |
● GCF, salivary, and serum oxidative stress index (OSI) were higher in group T1DM compared to the other groups at baseline (p < 0.05). ● GCF, salivary, and serum oxidative stress index (OSI) decreased 3 months after periodontal treatment in T1DM patients. |
A substantial level of oxidative stress may occur in children with T1DM, with increased oxidative stress index (OSI) in GCF, salivary, and serum samples. |
| Aroonrangsee et al., 2023 |
Cross-sectional case–control study |
40 participants from 15-23 years old. 20 T1DM patients and 20 age- matched non-T1DM subjects were enrolled. An average HbA1c level of less than 8% was considered the cut-off between well-controlled and poorly-controlled T1DM . Unstimulated whole saliva was collected before clinical periodontal exam. |
Salivary levels of OS biomarkers including malondialdehyde, protein carbonyl, total oxidant status (TOS), and total antioxidant capacity were determined using oxidative and antioxidative assays followed by spectrophotometric measurement at 375–532 nm. |
● T1DM was significantly associated with lower total oxidant status (TOS) in saliva (p<0.05). ● Increased TOS levels were significantly correlated with BOP. ● No relationship was found between OS biomarkers and HbA1c levels. |
Salivary total oxidant status (TOS) levels were related to both diabetes status and the extent of gingival inflammation. |
| Lappin et al., 2015 |
Cross-sectional study |
104 participants in the study: 19 healthy volunteers, 23 patients with periodontitis, 28 patients with T1DM, and 34 patients with T1DM and periodontitis. |
Levels of blood HbA1C were determined by high-performance liquid chromatography. Levels of IL-6, IL-8, and CXCL5 in plasma were determined by ELISA. |
● Higher levels of serum IL-8 in patients with T1DM and periodontitis compared to periodontitis alone. ● Higher serum levels of CXCL5 in T1DM patients compared to non-T1DM. ● No difference in plasma levels of IL-6 among the four groups. |
Elevated plasma levels of IL-8 potentially contribute to the cross-susceptibility between periodontitis and T1DM. |
| Passoja et al., 2011 |
Prospective clinical study |
80 subjects with T1DM (age 38.6 ± 12.3 y.o.) participated in the baseline study visit, while 58 subjects (age 39.5±12.6 y.o.) completed the visit after periodontal therapy. Periodontal therapy included oral hygiene education, scaling and root planning and patients were re-evaluated 8 weeks after periodontal therapy. Periodontal exam and blood samples were drawn at the baseline and in the follow-up visits. |
Serum IL-6 levels were measured using ELISA. | ● Significant association between the level of serum IL-6 and the number of sites with bleeding and PD ≥ 4mm at the baseline and after periodontal therapy. ● The reduction in the number of sites with bleeding and PD ≥ 4mm was lower in patients with higher serum IL-6 levels after periodontal therapy. |
Subjects with a high IL-6 serum level after therapy presented poorer periodontal healing than those with a low level. IL-6 may have a modulatory effect on host immune response in T1DM patients. |
| Salvi et al., 2010 | Prospective cohort study of experimental gingivitis (EG) |
A total of 18 Caucasian subjects (9 patients with T1DM and 9 without diabetes) (age 25.6 ± 5.8 y.o.) were included. EG: Patients were instructed to refrain from all oralhygiene practices for 21 days, resuming oral hygiene practices following the 21-day exam, continuing for an additional 2 weeks until Day 35. |
Periodontal exam and GCF was collected at baseline, Day 7, Day 14, Day 21 and Day 35. IL-1β, IL-8, MMP-8, and MMP-9 levels were determined by ELISA. |
● IL-1β levels in T1DM patients were higher compared to healthy individuals, and showed differences between groups at 7–21 days, while healthy patients showed IL-1b increases from baseline to 14–21 days (p<0.05). ● MMP-9 levels between patients with and without T1DM at 7–14 days (p<0.05). |
GCF IL-1β and MMP-9 were most significantly elevated in T1DM subjects compared with healthy individuals during EG, not resulting from differences in the plaque index (PI) or microbial composition. |
| Aspriello et al., 2011 |
Cross-sectional study |
Plasma C-reactive protein and GCF IL-1β, IL-6 and TNF- α were measured in periodontitis patients affected by T1DM (n=24) and type 2 diabetes mellitus (T2DM) (n=24). T1DM patients had a significantly lower age (43.5± 6.5 y.o) compared to T2DM ones (63.5± 15.5 y.o). |
Plasma high-sensitive C-reactive protein (hs-CRP) concentrations were measured by a particle-enhanced immunoturbidimetric assay. GCF mediators were measured with ELISA. |
● No differences in any clinical periodontal parameters between T1DM and T2DM periodontitis patients. ● GCF IL-1β and TNF- α were higher in T1DM periodontitis patients compared to T2DM periodontitis ones. ● GCF IL-1β and TNF-α levels were negatively correlated with diabetes duration and are higher in cases of recent onset of diabetes mellitus. |
GCF IL-1β and TNF-α levels were higher in T1DM periodontitis patients compared to T2DM periodontitis ones. GCF IL-1β and TNF-α levels higher in cases of recent onset of diabetes mellitus highlighting the need for periodontal therapy at the early stages of T1DM development. |
| Musial et al., 2021 |
Cross-sectional study |
20 T1DM patients after simultaneous pancreas and kidney transplantation (SPK) and 16 after kidney transplantation (KTx), and 15 non-diabetic kidney recipients (control) were included. The minimal post-transplant follow-up period was 12 months. |
GCF samples were collected and IL-1β, TNF-α, resistin, YKL-40 were measured with ELISA. | ● GCF concentration of all analyzed inflammation markers was lower in the SPK group than in the group of T1D patients after KTx (P<0.001) ● Patients with T1DM after SPK showed lower GCF levels of all inflammatory markers and presented reduced intensity of periodontitis compared to kidney recipients treated with insulin but also to T1DM patients without any therapy. |
Good metabolic control achieved by simultaneous pancreas and kidney transplantation (SPK) can decrease severity of periodontal inflammation in patients with end-stage renal disease caused by T1DM. |
| Lappin et al., 2009 |
Cross-sectional study |
Plasma concentrations of receptor activator of nuclear factor-kB ligand (RANKL), osteoprotegerin (OPG), C-terminal telopeptide of type 1 collagen and osteocalcin were measured in T1DM patients (n=63) and non-diabetics (n=38). The age range of the subjects was 22–56 years. |
Plasma levels of RANKL, OPG, C-terminal telopeptide of type 1 collagen and osteocalcin were measured with ELISA. | ● T1DM patients had significantly lower osteocalcin concentrations, lower RANKL to OPG ratios and higher OPG concentrations than non-diabetics. ● Osteocalcin had a negative correlation while OPG had a positive correlation with HbA1C. |
T1DM patients with periodontitis showed lower serum osteocalcin and higher OPG levels than non-diabetic periodontitis patients, suggesting that T1DM patients have a decreased intrinsic ability to replace bone when that has been destroyed during ‘‘acute bursts’’ of periodontitis. |
|
Chairatnathrongporn et al., 2022 |
Cross-sectional study |
Twenty patients with T1DM and twenty age-matched non-T1DM patients participated (age: 18.35 ± 2.01 years). Periodontal exams and unstimulated whole saliva was collected. |
RNA analysis of salivary samples for RANK, RANKL and OPG gene expression was conducted. |
● Patients with T1DM had more gingival inflammation and a higher percentage of full mouth gingival bleeding than the non-T1DM group, while plaque index (PI) was not significantly different. ● The relative mean mRNA levels of the RANK and RANKL genes, and the RANKL:OPG ratio demonstrated higher in the T1DM group than in the non-T1DM group. |
More studies aiming to understand the role of bone metabolism by exploring bone markers are needed in patients with T1DM and periodontal diseases. |
Type I Diabetes Mellitus & Host Immune Response
Oxidative Stress
Host Immune Markers
General Conclusions and Future Suggestions
References
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