Effect of Periodontal Treatment on Reducing Chronic Inflammation in Systemically Healthy Patients With Periodontal Disease.

BACKGROUND: We determined the effects and an accurate marker of periodontal treatment on serum interleukin (IL)-6 and high-sensitivity C-reactive protein (HsCRP) levels in systemically healthy individuals with periodontal disease. METHODS: This multicenter study included systemically healthy individuals with periodontal disease who received initial periodontal treatment and had no periodontal treatment history. Periodontal parameters, including periodontal inflamed surface area, masticatory efficiency, and periodontal disease classification; serum IL-6 and HsCRP levels; and serum immunoglobulin (Ig)G titers against periodontal pathogens were evaluated at baseline and after treatment. Subjects were classified as low or high responders (group) based on periodontal inflamed surface area changes. RESULTS: There were 153 participants. Only periodontal inflamed surface area changes were markedly different between low and high responders. Periodontal treatment (time point) decreased both serum IL-6 and HsCRP levels. The interaction between group and time point was remarkable only for serum IL-6 levels. Changes in serum immunoglobulin (Ig)G titers against periodontal pathogens were not associated with IL-6 changes in high responders. We analyzed the indirect effect of serum anti-Porphyromonas gingivalis type 2 IgG titer changes using mediation analysis and found no significance. However, the direct effect of group (low or high responder) on IL-6 changes was considerable. CONCLUSIONS: Periodontal treatment effectively decreased serum IL-6 levels, independent of periodontal pathogen infection, in systemically healthy individuals with periodontal disease.

Periodontal Pathogens Inhabit Root Caries Lesions Extending beyond the Gingival Margin: A Next-Generation Sequencing Analysis.

We performed a comprehensive microbiome analysis of root caries lesions using 22 teeth extracted from patients with severe periodontitis. The carious lesions were mechanically collected and cryo-pulverized following tooth extraction. Differences in the microbiome were compared between independent lesions at the supragingival site (SG) and lesions extending beyond the gingival margin (GCB). DNA was extracted and the microbiome was characterized on the basis of the V3-V4 hypervariable region of the 16S rRNA gene using paired-end sequencing on an Illumina MiSeq device. The microbiota in root caries lesions showed compositionally distinct microbiota depending on the location. The most abundant OTUs in the SG group were Streptococcus (26.0%), Actinomyces (10.6%), and Prevotella (7.6%). GCB presented Prevotella (11.1%) as the most abundant genus, followed by Fusobacterium (9.6%) and Actinomyces (8.7%). The SG group showed a lack of uniformity in microbiota compared with the GCB group. The bacterial profiles of GCB varied considerably among patients, including periodontal pathogens such as Porphyromonas, Selenomonas, Filifactor, Peptococcus, and Tannerella. Periodontal pathogens inhabit root caries lesions that extend beyond the gingival margin. This study provides a new perspective for elucidating the microbial etiology of root caries.

Efficacy of Erbium:YAG Laser for Regenerative Surgical Treatment of Peri-implantitis: Clinical, Microbiological, and Biomarker Analyses.

This paper reports on a study undertaken to ascertain the efficacy of the erbium:YAG laser (EYL) for peri-implantitis treatment. A total of 12 patients with bone loss resulting from peri-implantitis were involved in this study. The treatment protocol consisted of using the EYL for implant surface debridement and deproteinized bovine bone mineral (DBBM) for bone grafting. The following parameters were analyzed: probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing (BOP), bone levels (BLs), and the lipopolysaccharide levels before and after debridement with the EYL. This study found a statistically significant improvement in PPD, CAL, BOP, and BL at 3 and 12 months postoperative. Furthermore, a statistically significant decrease in implant-surface LPS levels was observed following debridement with the EYL. These findings show that using the EYL for debridement in peri-implantitis cases is effective in decreasing LPS levels. Moreover, after partial reconstruction with DBBM grafting, BLs were restored for at least 12 months. It was shown in one case that BLs had remained stable over 6 years, which also attests to the efficacy of this treatment. The combined use of EYL and DBBM could be effective for regenerative surgical peri-implantitis treatment.

ß 2-Microglobulin and Neutrophil Gelatinase-Associated Lipocalin, Potential Novel Urine Biomarkers in Periodontitis: A Cross-Sectional Study in Japanese.

OBJECTIVES: Several serum biomarkers have been reported to increase in periodontitis patients as possible mediators linking periodontal inflammation to systemic diseases. However, the relationship between periodontitis and urine biomarkers is still unclear. The aim of this cross-sectional study was to investigate potential urine biomarkers of periodontitis in a Japanese population. MATERIALS AND METHODS: This study included 108 male subjects, and microbiological and clinical parameters were evaluated as a periodontitis marker. The correlation between nine urine biomarkers (typically used to diagnose kidney disease) and periodontal parameters was analyzed. Based on the findings, ß 2-microglobulin (ß 2-MG) and neutrophil gelatinase-associated lipocalin (NGAL) were selected for comparison and multivariate regression analysis, and the Kruskal-Wallis test followed by Bonferroni correction was used to identify differences in their concentrations between the three periodontitis groups (severe, moderate, and no/mild periodontitis). RESULTS: ß 2-MG and NGAL exhibited a significant correlation with clinical parameters of periodontitis. The prevalence of clinical parameters such as bleeding on probing and number of sites with probing depth (PD) ≥ 6 mm were greater in the ß 2-MG high group (≥300 µg/g creatinine) than in the normal group (P=0.017 and 0.019, respectively). Multivariate regression analysis indicated that the number of sites with PD ≥ 6 mm was independently associated with urine ß 2-MG. Moreover, the number of sites with the clinical attachment level (CAL) ≥ 6 mm was greater in the NGAL high group (highest quartile) (P=0.041). Multivariate regression analysis showed that the number of sites with CAL ≥ 6 mm was associated independently with urine NGAL. Finally, ß 2-MG was significantly higher in the severe periodontitis subjects compared to the no/mild periodontitis subjects. CONCLUSION: The significant association between urine ß 2-MG or NGAL and periodontitis was revealed. These biomarkers can potentially be used to screen for or diagnose periodontitis. This trial is registered with the UMIN Clinical Trials Registry UMIN000013485.

Effectiveness of an erbium-doped: yttrium, aluminum and garnet laser for treatment of peri-implant disease: Clinical, microbiological, and biochemical marker analyses.

BACKGROUND: The effectiveness of an erbium-doped: yttrium, aluminum and garnet (Er: YAG) laser (EYL) for the treatment of peri-implant disease (PID) remains unclear. The aim of this study was to compare non-surgical EYL therapy for PID with locally delivered minocycline hydrochloride (MC) ointment therapy by evaluating clinical, microbiological, and biochemical markers. MATERIAL AND METHODS: Thirty-seven patients with PID were randomly assigned to either the EYL group (n = 18) or the MC group (n = 19). The clinical, microbiological, and biochemical markers at baseline and at 1 and 3 months after treatment were compared between the two groups. Subgingival plaque and peri-implant crevicular fluid (PICF) were collected from the diseased pockets. RESULTS: In the EYL group, probing pocket depth (PPD) was significantly decreased after treatment when compared with baseline. On the other hand, in the MC group, there was no significant decrease in PPD after treatment. Specific bacteria associated with PID were not determined. The counts of both Gram-positive and -negative species did not significantly decrease in the EYL group at 3 months after treatment. In the MC group, the counts of almost all bacterial species were significantly decreased after treatment. Biochemical marker analysis of PICF revealed significantly lower levels of metalloproteinase (MMP)-9 in the EYL group, as compared with the MC group at 3 months after treatment (p= 0.009). CONCLUSIONS: Non-surgical therapy with an EYL for PID was clinically effective, with decreased MMP-9 levels in PICF, which may lead to reduced peri-implant tissue destruction. Key words:Er: YAG laser; peri-implant disease; biomarker; peri-implant crevicular fluid.

Effects of Antimicrobial Photodynamic Therapy and Local Administration of Minocycline on Clinical, Microbiological, and Inflammatory Markers of Periodontal Pockets: A Pilot Study.

OBJECTIVE: We evaluated the efficacies of antimicrobial photodynamic therapy (aPDT) and minocycline ointment (MO) on clinical and bacteriological markers and the local host inflammatory response. MATERIALS AND METHODS: A total of 30 patients with chronic periodontitis were randomly assigned to two groups. Selected periodontal pockets (probing depth 5-7 mm with bleeding on probing) were treated with aPDT or MO. Measurements of clinical parameters and the collection of gingival crevicular fluid (GCF) and subgingival plaque were performed at baseline, and at 1 and 4 weeks after treatment. Quantification of periodontopathic bacteria in the sulcus and a multiplex bead immunoassay of ten inflammatory cytokines in the GCF were performed. RESULTS: Local MO administration exhibited a significant decrease in scores for clinical parameters (P < 0.01) and a significant reduction in bacterial counts (P < 0.01) and interleukin-1ß and interferon-γ levels at 1 and 4 weeks after treatment (P < 0.01). No significant changes were observed in the aPDT group, except in clinical parameters. CONCLUSIONS: Although our study had some limitations, we found that while local administration of MO may slightly help to improve clinical, microbiological, and crevicular cytokine levels in periodontal pockets, aPDT did not show any effects. This trial is registered with the UMIN Clinical Trials Registry UMIN000013376.

Interleukin-6 gene promoter methylation in rheumatoid arthritis and chronic periodontitis.

BACKGROUND: Methylation status of the cytokine genes may play a role in the pathogenesis of inflammatory diseases, such as rheumatoid arthritis (RA) and chronic periodontitis (CP). This study was undertaken to evaluate whether the DNA methylation profile of the interleukin-6 (IL-6) gene promoter was unique to individuals with RA and CP. METHODS: The study participants consisted of 30 patients with RA, 30 patients with CP, and 30 age-, sex-, and smoking status-balanced healthy controls. Genomic DNA isolated from peripheral blood was modified by sodium bisulfite and analyzed for DNA methylation levels of IL-6 gene with direct sequencing. Levels of IL-6 were determined by an enzyme-linked immunosorbent assay. RESULTS: The region of IL-6 gene promoter from -1200 to +27 bp was shown to contain 19 CpG motifs. The methylation levels of the CpG motif at -74 bp were significantly lower in patients with RA and CP than those in controls (P = 0.0001). Both levels of serum IL-6 and IL-6 production by mononuclear cells were significantly different between individuals with and without the methylation at -74 bp (P = 0.03). The +19 bp motif exhibited differential levels of the methylation among the groups, which was not associated with serum levels of IL-6. The other 17 CpG motifs exhibited comparable levels of the methylation between the groups. CONCLUSION: These results suggest that hypomethylated status of a single CpG in the IL-6 promoter region may lead to increased levels of serum IL-6, implicating a role in the pathogenesis of RA and CP.

Antibody responses to periodontopathic bacteria in relation to rheumatoid arthritis in Japanese adults.

BACKGROUND: Periodontopathic bacteria have been implicated as contributory to the etiology of rheumatoid arthritis (RA). Anticyclic citrullinated peptide (CCP) antibodies and rheumatoid factor (RF) were shown to be associated with RA. This study examines whether serum levels of antibodies to periodontopathic bacteria may affect clinical and laboratory profiles of RA. METHODS: The study participants consisted of 80 patients with RA, and 38 age-, sex-, smoking status-, and periodontal condition-balanced healthy controls. After periodontal and rheumatologic examination, serum levels of immunoglobulin G (IgG) antibodies to Porphyromonas gingivalis (Pg), Prevotella intermedia, Aggregatibacter actinomycetemcomitans (Aa) (previously Actinobacillus actinomycetemcomitans), and Eikenella corrodens (Ec) and those of anti-CCP antibodies and RF were determined by an enzyme-linked immunosorbent assay. RESULTS: Patients with RA showed significantly higher levels of anti-Pg and anti-CCP antibodies than controls (P = 0.04 and P <0.0001). In contrast, IgG responses to Aa and Ec in patients with RA were significantly lower than those in controls (P <0.0001 and P = 0.0001). Multiple logistic regression analysis revealed a significant association of anti-Pg and anti-Aa IgG responses with RA, after adjustment for age, sex, and smoking (P = 0.005 and P = 0.02). Anti-Pg titer displayed a significant correlation with RF levels, probing depth, and clinical attachment level (P = 0.03, P = 0.03, and P = 0.02). CONCLUSION: These results suggest that serum levels of anti-Pg IgG antibodies were associated with RA, and might affect serum levels of RF and periodontal condition in patients with RA.

Effects of irrigation with an antiseptic and oral administration of azithromycin on bacteremia caused by scaling and root planing.

BACKGROUND: Transient bacteremia frequently occur secondary to several periodontal procedures. The purpose of the present study is to investigate the effects of irrigation with an essential oil-containing antiseptic (EO) and oral administration of azithromycin (AZM) on bacteremia caused by scaling and root planing (SRP). METHODS: Thirty patients with chronic periodontitis were randomly assigned to three groups (control, EO, and AZM). The EO group received quadrant subgingival irrigation with EO, and mouthrinsing was continued at home for 1 week. Oral administration of AZM was started 3 days before SRP in the AZM group. No adjunctive treatment was performed before SRP in the control group. Peripheral blood and subgingival plaque were collected at baseline and after 1 week. The second blood sample was taken 6 minutes after the initiation of quadrant SRP. The blood samples were cultured and analyzed for bacteremia. Quantitative analysis of periodontopathic bacteria in the sulcus was performed using the polymerase chain reaction Invader method. RESULTS: Bacteremia incidence rates were 90%, 70%, and 20% for the control, EO, and AZM groups, respectively. Significant reduction of the incidence of bacteremia was shown in the AZM group only (P <0.01). Subgingival bacterial counts significantly decreased in both the EO and AZM groups (P <0.01). CONCLUSIONS: Quadrant SRP frequently induced bacteremia. Although AZM was effective in reducing bacteremia incidence, EO showed less effectiveness.

Serum cytokine and periodontal profiles in relation to disease activity of rheumatoid arthritis in Japanese adults.

BACKGROUND: Rheumatoid arthritis (RA) and periodontitis are common chronic inflammatory conditions and share many pathologic features. A similar profile of cytokines is involved in the pathogenesis of the two diseases. The relationship between the disease activity of RA and the periodontal condition remains unclear. This study examines whether the disease activity of RA affects serum cytokine and periodontal profiles. METHODS: The study subjects consisted of 84 Japanese adults with RA and 22 race-matched control individuals. After periodontal and rheumatologic examination, the disease activity of RA was determined with the Disease Activity Score including 28 joints using C-reactive protein (DAS28-CRP). Serum levels of cytokines including interleukin (IL)-1beta, IL-6, IL-12, IL-12 p40, IL-18, and tumor necrosis factor-alpha (TNF-alpha) were determined by an enzyme-linked immunosorbent assay. High-sensitive CRP was also measured with a latex particle-enhanced nephelometric method. RESULTS: Of 84 patients with RA, 28 and 56 patients exhibited low and moderate to high disease activity, respectively. Serum levels of IL-6, TNF-alpha, and CRP were significantly different between the two groups (P <0.05). Additionally, a significant correlation was observed between DAS28-CRP and percentage of sites with bleeding on probing (BOP) (P = 0.008) and between serum TNF-alpha levels and percentage of sites with BOP (P = 0.01) in 56 patients with RA with moderate to high activity. CONCLUSION: These results suggest that the disease activity of RA correlated with serum levels of IL-6, TNF-alpha, and CRP, and it might influence BOP in the patients with moderate to high disease activity.

The effect of periodontal treatment on serum leptin, interleukin-6, and C-reactive protein.

BACKGROUND: Previous studies suggest that periodontitis is closely related to obesity and metabolic syndrome. Leptin, a pleiotrophic hormone produced by adipose tissue, has been reported to be related to periodontitis. This study investigates the effects of periodontal treatment on the serum levels of leptin and other cytokines in patients with chronic periodontitis (CP). METHODS: Serum samples were taken from 33 CP patients (22 non-smokers, 11 smokers) and 18 healthy subjects. The serum leptin, adiponectin, tumor necrosis factor-alpha, interleukin (IL)-6, and C-reactive protein (CRP) levels were measured before and after non-surgical periodontal treatment. RESULTS: Significant differences between healthy and CP patients were found in serum leptin, IL-6, and CRP levels (P = 0.0018, P = 0.0064, and P = 0.0095, respectively). The serum leptin level was associated with mean probing depth, mean clinical attachment level, mean alveolar bone loss, and body mass index. There were significant associations between serum leptin levels and IL-6 and CRP levels. After non-surgical periodontal treatment, serum leptin, IL-6, and CRP levels were significantly decreased (mean +/- SD before and after, P value, respectively: leptin, 8.02 +/- 5.5, 7.10 +/- 4.4, P = 0.015; IL-6, 1.73 +/- 1.02, 1.36 +/- 0.73, P = 0.048; and CRP, 802.0 +/- 1065, 491.2 +/- 479.3, P = 0.047). CONCLUSIONS: Periodontal treatment is effective in reducing serum leptin, IL-6, and CRP levels. The results suggest that leptin, IL-6, and CRP could be mediating factors that connect metabolic syndrome and periodontitis.

Cytokine gene polymorphisms associated with rheumatoid arthritis and periodontitis in Japanese adults.

BACKGROUND: Cytokines play a major role in the pathogenesis of rheumatoid arthritis (RA) and periodontitis. Both diseases were previously shown to be partly influenced by cytokine gene polymorphisms. Therefore, we evaluated whether the distributions of the cytokine genotypes were unique to subjects with both diseases. METHODS: The study subjects consisted of Japanese adults with RA (RA group; n = 153), periodontitis only (P group; n = 117), and healthy individuals (H group; n = 108). Clinical periodontal condition was defined by measurements of probing depth, clinical attachment level, and bleeding on probing. Genomic DNA was isolated from peripheral blood and analyzed for the determination of 16 gene polymorphisms encoding interleukin (IL)-1, -2, -4, -6, and -10, tumor necrosis factor-alpha, and transforming growth factor-beta 1. RESULTS: The frequency of patients with RA who exhibited periodontitis was 89.5% (RA + P group; n = 137). No significant differences were observed in any of the frequencies of cytokine genotypes and alleles among the subject groups. After adjustment for age, gender, and smoking status, multiple logistic regression analysis revealed a significant difference in the distribution of IL-1B +3954 genotypes between RA + P and P groups (P = 0.006) and between RA + P and H groups (P = 0.008). CONCLUSION: Japanese individuals with RA and periodontitis may exhibit different distributions of IL-1B +3954 genotypes than healthy controls and subjects with periodontitis only.

Effects of treatment on soluble tumour necrosis factor receptor type 1 and 2 in chronic periodontitis.

AIM: We reported that soluble tumour necrosis factor receptor type 2 (sTNFR2)/type 1 (sTNFR1) ratios in gingival crevicular fluid (GCF) decreased as the severity of chronic periodontitis (CP) increased. This study investigated the effects of the periodontal treatment on TNF-alpha, sTNFR1 and R2 in GCF and serum of CP patients. MATERIAL AND METHODS: Thirty-five serum and 90 GCF samples were obtained from 35 CP patients (23 non-smokers and 12 smokers) at baseline and after treatment. The levels of TNF-alpha, sTNFR1 and R2 in serum and GCF were quantified by enzyme-linked immunosorbant assay. RESULTS: No significant differences were found in the serum levels of TNF-alpha, sTNFR1 and R2 and the ratio of sTNFR2/R1 between baseline and after treatment. After treatment, sTNFR1 and R2 levels in GCF of non-smokers and smokers were significantly decreased compared with baseline. However, the sTNFR2/R1 ratio was significantly increased (non-smoker: 0.56+/-0.03-0.84+/-0.03, p<0.0001; smoker: 0.59+/-0.06-0.85+/-0.04, p=0.0019). There were no significant differences between non-smoking and smoking CP groups in serum and GCF. CONCLUSION: The ratio of sTNFR2/R1 in GCF significantly increased after treatment, and could be related to the clinical state of CP.

Interleukin-6 receptor gene polymorphisms and periodontitis in a non-smoking Japanese population.

AIM: The indispensable role of interleukin-6 receptor (IL-6R) in regulating IL-6 responses has been clearly established. We have previously reported that IL6R polymorphisms strongly influenced the serum levels of soluble IL-6R. In this study, we investigated the association between these genetic variations and periodontitis. MATERIAL AND METHODS: Among the seven novel IL6R single-nucleotide polymorphisms (SNPs) reported, we genotyped two important sites: the +48892 A/C in exon 9 and the -183 G/A in the promoter region. The SNP in exon 9 results in Asp-->Ala substitution in the proteolytic cleavage site of IL-6Ralpha. In total, 212 periodontitis cases and 210 healthy controls were genotyped using polymerase chain reaction, restriction fragment length polymorphisms and direct sequencing methods. RESULTS: Analysis of the genotype distribution of the +48892 A/C SNP in periodontitis patients and in controls revealed a suggestive association with aggressive (p = 0.04) and chronic periodontitis (p = 0.04). In addition, the carriage rate for the A allele was significantly higher in chronic periodontitis patients [p = 0.02, odds ratio (OR) = 2.25]. No association was found in the -183 G/A SNP. The two markers were in linkage disequilibrium (LD) (|D'| = 0.53). CONCLUSION: The IL6R+48892 A/C polymorphism could act as a risk factor for periodontitis; however, further association and biological studies are needed.

Imbalance between soluble tumour necrosis factor receptors type 1 and 2 in chronic periodontitis.

BACKGROUND: Soluble types of tumour necrosis factor (TNF) receptors type 1 and 2 modulate the TNF-alpha-mediated inflammatory responses in chronic periodontitis (CP). OBJECTIVES: This study investigated the levels of TNF-alpha, soluble TNF receptor type 1 and 2 in gingival crevicular fluid (GCF) and serum of healthy subjects and CP patients. MATERIALS AND METHODS: Thirty-eight sera and 73 GCF samples were collected from 16 healthy subjects and 22 CP patients. GCF was collected from probing pocket depth (PPD)< or =3 mm sites of healthy subjects, PPD< or =3, 4-6 and > or =7 mm sites of CP patients. The levels of TNF-alpha, soluble TNF receptor type 1 and 2 in the serum and GCF were quantified by enzyme-linked immunosorbant assay. RESULTS: The total amounts of TNF-alpha, soluble TNF receptor type 1 and 2 in GCF significantly elevated with increasing PPD in both site-based (p<0.05) and subject-based (p<0.05) analyses. However, their levels progressively diverged as the pocket depths increased, with the soluble TNF receptor type 2 level being comparatively lower than type 1. On the other hand, soluble TNF receptor type 2/type 1 ratios in GCF decreased as the severity of periodontitis increased (p<0.0001). CONCLUSION: The imbalance between soluble TNF receptor type 1 and 2 levels in GCF could be related to CP severity.