Full-mouth treatment modalities (within 24 hours) for periodontitis in adults.

BACKGROUND: Periodontitis is a highly prevalent, chronic inflammation that causes damage to the soft tissues and bones supporting the teeth. Conventional treatment is quadrant scaling and root planing (the second step of periodontal therapy), which comprises scaling and root planing of teeth in one quadrant of the mouth at a time, with the four different sessions separated by at least one week. Alternative protocols for anti-infective periodontal therapy have been introduced to help enhance treatment outcomes: full-mouth scaling (subgingival instrumentation of all quadrants within 24 hours), or full-mouth disinfection (subgingival instrumentation of all quadrants in 24 hours plus adjunctive antiseptic). We use the older term 'scaling and root planing' (SRP) interchangeably with the newer term 'subgingival instrumentation' in this iteration of the review, which updates one originally published in 2008 and first updated in 2015. OBJECTIVES: To evaluate the clinical effects of full-mouth scaling or full-mouth disinfection (within 24 hours) for the treatment of periodontitis compared to conventional quadrant subgingival instrumentation (over a series of visits at least one week apart) and to evaluate whether there was a difference in clinical effects between full-mouth disinfection and full-mouth scaling. SEARCH METHODS: An information specialist searched five databases up to 17 June 2021 and used additional search methods to identify published, unpublished and ongoing studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) lasting at least three months that evaluated full-mouth scaling and root planing within 24 hours, with or without adjunctive use of an antiseptic, compared to conventional quadrant SRP (control). Participants had a clinical diagnosis of (chronic) periodontitis according to the International Classification of Periodontal Diseases from 1999. A new periodontitis classification was launched in 2018; however, we used the 1999 classification for inclusion or exclusion of studies, as most studies used it. We excluded studies of people with systemic disorders, taking antibiotics or with the older diagnosis of 'aggressive periodontitis'. DATA COLLECTION AND ANALYSIS: Several review authors independently conducted data extraction and risk of bias assessment (based on randomisation method, allocation concealment, examiner blinding and completeness of follow-up). Our primary outcomes were tooth loss and change in probing pocket depth (PPD); secondary outcomes were change in probing attachment (i.e. clinical attachment level (CAL)), bleeding on probing (BOP), adverse events and pocket closure (the number/proportion of sites with PPD of 4 mm or less after treatment). We followed Cochrane's methodological guidelines for data extraction and analysis. MAIN RESULTS: We included 20 RCTs, with 944 participants, in this updated review. No studies assessed the primary outcome tooth loss. Thirteen trials compared full-mouth scaling and root planing within 24 hours without the use of antiseptic (FMS) versus control, 13 trials compared full-mouth scaling and root planing within 24 hours with adjunctive use of an antiseptic (FMD) versus control, and six trials compared FMS with FMD. Of the 13 trials comparing FMS versus control, we assessed three at high risk of bias, six at low risk of bias and four at unclear risk of bias. We assessed our certainty about the evidence as low or very low for the outcomes in this comparison. There was no evidence for a benefit for FMS over control for change in PPD, gain in CAL or reduction in BOP at six to eight months (PPD: mean difference (MD) 0.03 mm, 95% confidence interval (CI) -0.14 to 0.20; 5 trials, 148 participants; CAL: MD 0.10 mm, 95% CI -0.05 to 0.26; 5 trials, 148 participants; BOP: MD 2.64%, 95% CI -8.81 to 14.09; 3 trials, 80 participants). There was evidence of heterogeneity for BOP (I² = 50%), but none for PPD and CAL. Of the 13 trials comparing FMD versus control, we judged four at high risk of bias, one at low risk of bias and eight at unclear risk of bias. At six to eight months, there was no evidence for a benefit for FMD over control for change in PPD or CAL (PPD: MD 0.11 mm, 95% CI -0.04 to 0.27; 6 trials, 224 participants; low-certainty evidence; CAL: 0.07 mm, 95% CI -0.11 to 0.24; 6 trials, 224 participants; low-certainty evidence). The analyses found no evidence of a benefit for FMD over control for BOP (very low-certainty evidence). There was no evidence of heterogeneity for PPD or CAL, but considerable evidence of heterogeneity for BOP, attributed to one study. There were no consistent differences in these outcomes between intervention and control (low- to very low-certainty evidence). Of the six trials comparing FMS and FMD, we judged two trials at high risk of bias, one at low risk of bias and three as unclear. At six to eight months, there was no evidence of a benefit of FMD over FMS for change in PPD or gain in CAL (PPD: MD -0.11 mm, 95% CI -0.30 to 0.07; P = 0.22; 4 trials, 112 participants; low-certainty evidence; CAL: MD -0.05 mm, 95% CI -0.23 to -0.13; P = 0.58; 4 trials, 112 participants; low-certainty evidence). There was no evidence of a difference between FMS and FMD for BOP at any time point (P = 0.98; 2 trials, 22 participants; low- to very low-certainty evidence). There was evidence of heterogeneity for BOP (I² = 52%), but not for PPD or CAL. Thirteen studies predefined adverse events as an outcome; three reported an event after FMD or FMS. The most important harm identified was an increase in body temperature. We assessed the certainty of the evidence for most comparisons and outcomes as low because of design limitations leading to risk of bias, and the small number of trials and participants, leading to imprecision in the effect estimates. AUTHORS' CONCLUSIONS: The inclusion of nine new RCTs in this updated review has not changed the conclusions of the previous version of the review. There is still no clear evidence that FMS or FMD approaches provide additional clinical benefit compared to conventional mechanical treatment for adult periodontitis. In practice, the decision to select one approach to non-surgical periodontal therapy over another should include patient preference and the convenience of the treatment schedule.

DIFFERENTIAL IMPACT OF PERIODONTAL TREATMENT STRATEGIES DURING PREGNANCY ON PERINATAL OUTCOMES: A SYSTEMATIC REVIEW AND META-ANALYSIS.

OBJECTIVES: This study aimed to evaluate the impact of different periodontal treatment strategies during pregnancy on perinatal outcomes. STUDY SELECTION: This systematic review and meta-analysis of clinical trials was conducted according to PRISMA guidelines to assess the effect of mouthwash in addition to scaling and root planning (SRPM) on pregnancy outcomes, including preterm birth, low birth weight, gestational age, and birth weight. Pooled risk ratios (RR), mean differences (MD), and 95% confidence intervals (CI) were calculated using the random effect model. RESULTS: Twenty trials involving 5938 participants, including thirteen trials comparing scaling and root planning (SRP) and seven trials comparing SRPM with control groups. SRPM was associated with reduced risk of preterm birth (RR = 0.37; 95%CI = 0.16-0.84; P = .017; I2=93.26%; P < .001; number needed to treat (NNT): 3), low birth weight (RR = 0.54; 95%CI = 0.40-0.74; P < .0001; I2 = 0%; P = .46; NNT: 13), increased gestational age (MD = 0.78; 95%CI: 0.19-1.37; P = .009; I2 = 87.15%; P < .001), and birth weight (MD = 121.77; 95%CI = 3.19-240.34; P = .044; I2 = 80.68%; P < .001). There were no statistically significant differences in the analysis of SRP group, except for the increased birth weight (MD = 93.85; 95% CI = 3.27-184.42; P = .042; I2 = 84.11%; P < .001). CONCLUSION: Using mouthwash in addition to scaling and root planning (SRPM) for the treatment of periodontal disease during pregnancy significantly improves perinatal outcomes.

Does Treatment of Gingivitis During Pregnancy Improve Pregnancy Outcomes? A Systematic Review and Meta-Analysis.

PURPOSE: This study aimed to investigate whether treatment of gingivitis in pregnant women affects pregnancy outcomes. MATERIALS AND METHODS: This was a systematic review and meta-analysis of clinical trials using PRISMA guidelines to appraise the treatment of gingivitis on pregnancy outcomes, including preterm birth (less than 37 weeks), low birth weight (less than 2,500 g), gestational age and birth weight. Pooled odds ratios (OR), mean difference, and 95% confidence intervals (CI) were calculated using the random effect model. A search was conducted in databases including Medline, Pubmed, Web of Science, Google Scholar and Embase without restrictions regarding language or date of publication. RESULTS: Three clinical trials comprising 1,031 participants were included in this review. Treatment of gingivitis during pregnancy was associated with a decreased risk of preterm birth (OR = 0.44, 95% CI [0.20-0.98], P = 0.045) and higher birth weight (weighted mean difference (WMD) =105.36 g, 95% CI [36.72-174.01], P = 0.003). Gestational age at birth in the treatment group (WMD = 0.31 weeks, 95% CI [-0.02-0.64], P = 0.64) as well as likelihood of low birth weight (OR = 0.92, 95% CI [0.38-2.21], P = 0.851) did not reach statistical significance. CONCLUSION: The results of this meta-analysis indicate that treatment of gingivitis in pregnancy may improve pregnancy outcomes including increased infants birth weight and reduced preterm births. Future trials are warranted to validate the true effect size of gingivitis treatment on pregnancy outcomes.

The effect of adjuvant oral irrigation on self-administered oral care in the management of peri-implant mucositis: A randomized controlled clinical trial.

OBJECTIVES: This single-blinded randomized clinical trial evaluated the effect of adjuvant oral irrigation in addition to self-administered oral care on prevalence and severity of peri-implant mucositis. MATERIAL & METHODS: After randomization, patients suffering from peri-implant mucositis were assigned to the following: Group 1 (control) received oral hygiene instruction following a standardized protocol, including a sub- and supramucosal mechanical debridement. Group 2 and 3 additionally were instructed to use an oral irrigator with either water or 0.06% CHX solution. One implant per patient was considered for examination. Clinical examinations included Probing Depth, Bleeding on Probing (BOP-positive sites), and Modified Plaque and Gingival Index. A surrogate variable (mucositis severity score) was applied measuring severity of disease. Statistical analysis included linear regression models and sensitivity analysis. RESULTS: Sixty periodontally healthy patients were examined for presence and severity of peri-implant mucositis. 70% of all patients reached complete resolution of disease after 12 weeks. The prevalence of peri-implant mucositis after 12 weeks was 50% in group 1, 35% in group 2, and 5% in group 3. Average BOP-positive sites were reduced in all groups after 12 weeks (mean change from baseline: group 1: -1.5; group 2: -1.8; group 3: -2.3). CONCLUSION: Within the limits of the study, adjuvant use of an oral irrigator with 0.06% CHX in addition to mechanical biofilm removal and oral hygiene instruction can reduce the presence and severity of peri-implant mucositis after 12 weeks.

In Vitro Effects of Streptococcus oralis Biofilm on Peri-Implant Soft Tissue Cells.

Human gingival epithelial cells (HGEps) and fibroblasts (HGFs) are the main cell types in peri-implant soft tissue. HGEps are constantly exposed to bacteria, but HGFs are protected by connective tissue as long as the mucosa-implant seal is intact. Streptococcus oralis is one of the commensal bacteria, is highly abundant at healthy implant sites, and might modulate soft tissue cells-as has been described for other streptococci. We have therefore investigated the effects of the S. oralis biofilm on HGEps and HGFs. HGEps or HGFs were grown separately on titanium disks and responded to challenge with S. oralis biofilm. HGFs were severely damaged after 4 h, exhibiting transcriptional inflammatory and stress responses. In contrast, challenge with S. oralis only induced a mild transcriptional inflammatory response in HGEps, without cellular damage. HGFs were more susceptible to the S. oralis biofilm than HGEps. The pro-inflammatory interleukin 6 (IL-6) was attenuated in HGFs, as was interleukin 8 (CXCL8) in HGEps. This indicates that S. oralis can actively protect tissue. In conclusion, commensal biofilms can promote homeostatic tissue protection, but only if the implant-mucosa interface is intact and HGFs are not directly exposed.

Effects of six month personalized endurance training on work ability in middle-aged sedentary women: a secondary analysis of a randomized controlled trial.

BACKGROUND: To test the effects of guided endurance training on work ability in middle-aged female hospital workers of various occupations. METHODS: We randomized 265 healthy, sedentary, middle-aged women (45-65 years) to an endurance training group (EG 210 min/week) or a wait-list control group (CG). At baseline and at 6-month follow-up, we assessed work ability (Work Ability Index [WAI]), physical activity (Freiburger activity questionnaire) and peak oxygen uptake (VO2peak) by cardiopulmonary exercise testing. To examine the influence of baseline work ability, participants were divided into poor-moderate (WAI 1, 7-36 points, n = 83), good (WAI 2, 37-43 points, n = 136) and excellent (WAI 3, 44-49 points, n = 46) WAI subgroups. RESULTS: Cardiorespiratory fitness improved significantly after 6 months in the EG but not in the CG. The WAI total score increased significantly in the EG (38.3 ± 5.0 to 39.8 ± 4.9 points) but not in the CG (39.4 ± 4.7 to 39.3 ± 4.9 points), with a significant difference between groups (p < 0.01). In the EG, only the poor-moderate subgroup (WAI 1, 33.0 ± 2.9 to 36.6 ± 4.8 points, p < 0.05) increased the WAI total score, with this increase being significantly higher compared to the good (WAI 2, 40.2 ± 2.1 to, 40.4 ± 3.7 points) and excellent (WAI 3, 45.6 ± 1.5 to 45.7 ± 1.8 points) subgroup. CONCLUSIONS: A 6-month guided exercise training intervention significantly increases cardiorespiratory fitness with concomitant improvements in work ability in middle-aged previously sedentary hospital employees. Women with low baseline work ability seem to particularly benefit from the intervention, which implies that similar interventions may be particularly beneficial for this group of individuals. TRIAL REGISTRATION: German Clinical Trails Register Identifier: DRKS00005159. Registered 25 September 2013.

Keratinized mucosa width is associated with severity of peri-implant mucositis. A cross-sectional study.

OBJECTIVES: This is a cross-sectional study designed with the aim to assess associations between the width of keratinized tissue and peri-implant mucositis. MATERIALS AND METHODS: Two hundred and thirty one dental implants in 52 patients were evaluated. The width of keratinized mucosa (KM), plaque index (mPI), gingival index (mGI), bleeding on probing index (BoP), and the probing depth (PD) were measured clinically. Reduced KM was defined as a width of KM below 2 mm and 1 mm, respectively. In the primary analysis, data were analyzed on the implant level with the help of a generalized estimating equations (GEE) model. In sensitivity analyses, an adjusted linear mixed model was performed. RESULTS: Forty four implants in 12 patients had less than 2 mm KM, and 187 implants in 40 patients had ≥ 2 mm KM. In the non-adjusted analysis on the implant level, reduced keratinized tissue width was significantly associated with peri-implant mucositis (OR 3.3, 95%-CI (1.3-8.0), p = 0.009) and severity of disease (mean difference 2.5, 95%-CI (0.8-4.2) p = 0.004). In sensitivity analyses, reduced keratinized tissue showed a significant association with severity of disease (OR 1.7, 95%-confidence interval = 0.1-34, p = 0.040). CONCLUSION: A reduced width of keratinized tissue around dental implants is a risk indicator for severity of peri-implant mucositis. The overall tendency of the results indicates that a sufficient amount of KM may contribute to reduce risk for and severity of peri-implant mucositis.

Probing depth is an independent risk factor for HbA1c levels in diabetic patients under physical training: a cross-sectional pilot-study.

BACKGROUND: This cross-sectional study investigates the potential association between active periodontal disease and high HbA1c levels in type-2-diabetes mellitus subjects under physical training. METHODS: Women and men with a diagnosis of non-insulin-dependent diabetes mellitus and ongoing physical and an ongoing exercise program were included. Periodontal conditions were assessed according to the CDC-AAP case definitions. Venous blood samples were collected for the quantitative analysis of HbA1c. Associations between the variables were examined with univariate and multivariate regression models. RESULTS: Forty-four subjects with a mean age of 63.4 ± 7.0 years were examined. Twenty-nine subjects had no periodontitis, 11 had a moderate and 4 had a severe form of periodontal disease. High fasting serum glucose (p < 0.0001), high BMI scores (p = 0.001), low diastolic blood pressure (p = 0.030) and high probing depth (p = 0.036) were significantly associated with high HbA1c levels. CONCLUSIONS: Within the limitations of this study HbA1c levels are positively associated with high probing pocket depth in patients with non-insulin-dependent diabetes mellitus under physical exercise training. Control and management of active periodontal diseases in non-insulin-dependent patients with diabetes mellitus is reasonable in order to maximize therapeutic outcome of lifestyle interventions.

Higher sensitivity of swab polymerase chain reaction compared with tissue cultures for diagnosing periprosthetic joint infection.

PURPOSE: The aim of this study was to assess the diagnostic accuracy of swab polymerase chain reaction (PCR) compared with tissue culture as the current gold standard. METHODS: Forty-one consecutive patients were prospectively enrolled undergoing revision arthroplasty due to septic and aseptic reasons. Infection classification was done according to the criteria of the Musculoskeletal Infection Society. Intraoperatively, tissue samples of the periprosthetic membrane were collected for culture analysis, and swabs were taken from the accessible implant surface to perform 16S ribosomal RNA PCR. The diagnostic performance of swab PCR and tissue cultures was determined. RESULTS: Of the 41 patients, 53.7% ( n = 22) had a periprosthetic joint infection (PJI) and 46.3% ( n = 19) an aseptic loosening. Swab PCR showed a higher sensitivity than tissue cultures (86.4% vs. 68.2%), while the specificity was equal (89.5%). The area under the curve was 0.79 for tissue cultures and 0.88 for swab PCR. CONCLUSIONS: In this first investigation of swab PCR for diagnosing PJI, this procedure revealed a higher sensitivity for diagnosing PJI compared with tissue cultures. Because swab PCR is easily implementable and does not require special equipment, it can potentially improve the diagnosis of PJI.

Transcriptome-Wide High-Density Microarray Analysis Reveals Differential Gene Transcription in Periprosthetic Tissue From Hips With Chronic Periprosthetic Joint Infection vs Aseptic Loosening.

BACKGROUND: Differentiating between periprosthetic hip infection and aseptic hip prosthesis loosening can be challenging, especially in patients with chronic infections. This study used whole-genome microarray analysis to investigate the transcriptomes of periprosthetic hip tissues to identify genes that are differentially transcripted between chronic periprosthetic hip infection and aseptic hip prosthesis loosening. METHODS: In this pilot study, a total of 24 patients with either chronic periprosthetic hip infection (n = 12) or aseptic hip prosthesis loosening (n = 12) were analyzed. Periprosthetic hip infection was diagnosed based on modified criteria of the Musculoskeletal Infection Society. To evaluate differences in gene transcription, whole-genome microarray analysis was performed on the mRNA of periprosthetic tissue. RESULTS: Microarray analysis revealed differential gene transcription in periprosthetic hip tissue affected by chronic hip infection vs aseptic hip prosthesis loosening. A total of 39 genes had area under the curve values greater than 0.9 for diagnosing chronic periprosthetic hip infection; 5 genes had annotations relevant to infection and metabolism. The 39 genes also included 7 genes that were differentially transcribed but that have no apparent connection to immune response processes plus 27 genes with unknown function. CONCLUSION: Differences in gene transcription profiles might represent novel diagnostic targets that can be used to differentiate between chronic periprosthetic hip infections and aseptic hip prosthesis loosening. Secondary metabolites of differentially transcripted genes might serve as easily accessible markers for detecting chronic periprosthetic joint infection in future.

Antimicrobial dental implant functionalization strategies -A systematic review.

Biofilm formation on dental implant surfaces is a serious threat. Up to 50% of all implants show signs of irreversible tissue destruction. The aim of the present systematic review was to summarize the state of the art of strategies to functionalize antimicrobial dental implant surfaces. We searched the following electronic database: SCOPUS, MEDLINE and GOOGLE SCHOLAR and identified relevant controlled trials that evaluated the efficiency of new biomaterial strategies to modify dental implant surfaces, in such a way that biofilm formation was inhibited. The search yielded 2,990 potentially relevant publications. A total of 142 publications met the inclusion criteria. Analysis found that it may be concluded that silver-implanted surfaces, drug-loaded surfaces, surfaces with antimicrobial peptides, bioactive and biopassive polymer coatings as well as nanoscale or UV-activatable surfaces enhance antimicrobial activity compared to commercial pure titanium.

Diagnostic performance of swab PCR as an alternative to tissue culture methods for diagnosing infections associated with fracture fixation devices.

BACKGROUND: Molecular procedures could potentially improve diagnoses of orthopaedic implant-related infections, but are not yet clinically implemented. Analysis of sonication fluid shows the highest sensitivity for diagnosing implant infections in cases of revision surgery with implant removal. However, there remains controversy regarding the best method for obtaining specimens in cases of revision surgery with implant retention. Tissue culture is the most common diagnostic method for pathogen identification in such cases. Here we aimed to assess the diagnostic performance of swab PCR analysis compared to tissue culture from patients undergoing revision surgery of fracture fixation devices. METHODS: We prospectively investigated 62 consecutive subjects who underwent revision surgery of fracture fixation devices during a two-year period. Tissue samples were collected for cultures, and swabs from the implant surface were obtained for 16S rRNA PCR analysis. Subjects were classified as having an implant-related infection if (1) they presented with a sinus tract or open wound in communication with the implant; or (2) purulence was encountered intraoperatively; or (3) two out of three tissue cultures tested positive for the presence of the same pathogen. Tissue culture and swab PCR results from the subjects were used to calculate the sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), and area under the ROC curve (AUC) for identifying an orthopaedic implant-related infection. RESULTS: Orthopaedic implant-related infections were detected in 51 subjects. Tissue culture identified infections in 47 cases, and swab PCR in 35 cases. Among the 11 aseptic cases, tissue culture was positive in 2 cases and swab PCR in 4 cases. Tissue culture showed a significantly higher area under the ROC curve for diagnosing infection (AUC=0.89; 95% CI, 0.67-0.96) compared to swab PCR (AUC=0.66; 95% CI, 0.46-0.80) (p=0.033). CONCLUSIONS: Compared to swab PCR, tissue culture showed better performance for diagnosing orthopaedic implant-related infection. Although molecular methods are expected to yield higher diagnostic accuracy than cultures, it appears that the method of obtaining specimens plays an important role. Improved methods of specimen collection are required before swab PCR can become a reliable alternative to tissue-consumptive methods.

Interaction between periodontal disease and atherosclerotic vascular disease--Fact or fiction?

C-reactive protein (CRP) level is associated with the 10-year risk of an atherosclerotic vascular disease (ASVD), suggesting presence of systemic inflammation probably long before ASVD is present. Where, however, does this systemic inflammation come from? One active area of research has been the study of dental infection and various forms of periodontal disease (PD), both of which are highly prevalent in populations at risk for ASVD. Recent data show that ASVD and PD interact with each other via systemic release of specific pro- and anti-inflammatory cytokines, small signal molecules and enzymes which modulate initiation and progression of the chronic inflammatory reaction involved in both diseases. In addition, periodontal pathogens were identified within atherosclerotic lesions and thrombi isolated from myocardial infarction patients. LDL cholesterol, a strong risk factor for ASVD, is also associated with PD; and statins, used to treat ASVD, are also active to prevent or reduce PD. Finally, there is growing evidence for common genetic susceptibility factors involved in both diseases. These findings support commonalities with respect to the pathogenic mechanisms involved in both inflammatory diseases. Conversely, a causative relationship cannot yet be concluded in the absence of data from large longitudinal cohort and randomized controlled intervention trials.

The Peri-Implant and Periodontal Microbiota in Patients with and without Clinical Signs of Inflammation.

Late implant failures, caused by the inflammation of surrounding tissues are a problem in implant dentistry. The path of bacterial transmission from teeth to implants is not completely understood. Therefore, the purpose of this study was to analyze intraindividual bacterial transmission characterizing subgingival microbiomes in teeth and implants, both in healthy subjects and in those with signs of periodontitis or peri-implantitis. Samples of peri-implant and dental sulcus fluid were collected. To identify the predominant microbiota, amplified fragments of bacterial 16S rRNA gene were separated by single strand conformation polymorphism analysis, sequenced and taxonomically classified. A total of 25 different predominant genera were found in the diseased group and 14 genera in the healthy group. Species richness did not differ significantly between implants, neighboring teeth and teeth with largest probing depth in the diseased group. Additionally, no differences between teeth and implants in the healthy group were detected. In contrast, microbial diversity varied between the different sampling points. Species richness is similar in healthy and diseased sites, but the composition of the bacterial community differed within the individual subjects. The underlying analyses strongly suggest that complete transmission from neighboring teeth to implants is unlikely.

Pyrosequencing of supra- and subgingival biofilms from inflamed peri-implant and periodontal sites.

BACKGROUND: To investigate the microbial composition of biofilms at inflamed peri-implant and periodontal tissues in the same subject, using 16S rRNA sequencing. METHODS: Supra- and submucosal, and supra- and subgingival plaque samples were collected from 7 subjects suffering from diseased peri-implant and periodontal tissues. Bacterial DNA was isolated and 16S rRNA genes were amplified, sequenced and aligned for the identification of bacterial genera. RESULTS: 43734 chimera-depleted, denoised sequences were identified, corresponding to 1 phylum, 8 classes, 10 orders, 44 families and 150 genera. The most abundant families or genera found in supramucosal or supragingival plaque were Streptoccocaceae, Rothia and Porphyromonas. In submucosal plaque, the most abundant family or genera found were Rothia, Streptococcaceae and Porphyromonas on implants. The most abundant subgingival bacteria on teeth were Prevotella, Streptococcaceae, and TG5. The number of sequences found for the genera Tannerella and Aggregatibacter on implants differed significantly between supra- and submucosal locations before multiple testing. The analyses demonstrated no significant differences between microbiomes on implants and teeth in supra- or submucosal and supra- or subgingival biofilms. CONCLUSION: Diseased peri-implant and periodontal tissues in the same subject share similiar bacterial genera and based on the analysis of taxa on a genus level biofilm compositions may not account for the potentially distinct pathologies at implants or teeth.

Evaluation of FTA ® paper for storage of oral meta-genomic DNA.

AIM: The purpose of the present study was to evaluate the short-term storage of meta-genomic DNA from native oral biofilms on FTA(®) paper. MATERIALS AND METHODS: Thirteen volunteers of both sexes received an acrylic splint for intraoral biofilm formation over a period of 48 hours. The biofilms were collected, resuspended in phosphate-buffered saline, and either stored on FTA(®) paper or directly processed by standard laboratory DNA extraction. The nucleic acid extraction efficiencies were evaluated by 16S rDNA targeted SSCP fingerprinting. The acquired banding pattern of FTA-derived meta-genomic DNA was compared to a standard DNA preparation protocol. Sensitivity and positive predictive values were calculated. RESULTS: The volunteers showed inter-individual differences in their bacterial species composition. A total of 200 bands were found for both methods and 85% of the banding patterns were equal, representing a sensitivity of 0.941 and a false-negative predictive value of 0.059. CONCLUSION: Meta-genomic DNA sampling, extraction, and adhesion using FTA(®) paper is a reliable method for storage of microbial DNA for a short period of time.

Health- and disease-associated species clusters in complex natural biofilms determine the innate immune response in oral epithelial cells during biofilm maturation.

The aim of the present study was to verify our hypothesis concerning the differential induction of various antimicrobial and immunomodulatory responses in oral epithelial cells by diverse bacterial species clusters. For this purpose, oral biofilms between 1 and 14 days of maturation (36 volunteers) were co-incubated with gingival epithelial cells. Subsequently, human ß-defensin (hBD)-2, hBD-3, LL-37, interleukin (IL)-1ß, IL-6, IL-8 and IL-10 mRNA expression profiles were quantified by quantitative reverse transcription PCR. The correlation between bacterial species and the host innate immune response was determined by relating these results to existing 16S rRNA phylogenetic analysis by amplicon sequencing (Langfeldt et al. 2014. PLoS One 9: e87449). Data were analysed by multiple factor analysis. Transcription of hBD-2 and hBD-3 was significantly associated with the abundance of species of the Prevotella cluster and the absence of species of the Streptococcus cluster. IL-1ß, -6, -8 and -10 mRNA syntheses were significant correlated with Leptotrichia species [Leptotrichia 302H02 (0.448, P < 0.0001), Leptotrichia nbw822e09c1 (0.214, P = 0.008) and Leptotrichia wadei (0.218, P = 0.007)] of the Prevotella cluster. In the third dimension IL-10 and members of the Prevotella cluster were negatively correlated, whereas hBD-3 and IL-1ß, IL-6 and IL-8 were positive correlated to axis 3, like members of the Proteobacteria cluster. In conclusion, distinct species of health- and disease-associated bacterial clusters induce antibacterial or immunomodulatory reactions in oral epithelial cells during early stages of bacteria-host interactions.

SLC23A1 polymorphism rs6596473 in the vitamin C transporter SVCT1 is associated with aggressive periodontitis.

AIM: Identification of variants within genes SLC23A1 and SLC23A2 coding for vitamin C transporter proteins associated with aggressive (AgP) and chronic periodontitis (CP). MATERIAL AND METHODS: Employment of three independent case-control samples of AgP (I. 283 cases, 979 controls; II. 417 cases, 1912 controls; III. 164 cases, 357 controls) and one sample of CP (1359 cases, 1296 controls). RESULTS: Stage 1: Among the tested single-nucleotide polymorphisms (SNPs), the rare allele (RA) of rs6596473 in SLC23A1 showed nominal significant association with AgP (p = 0.026, odds ratio [OR] 1.26, and a highly similar minor allele frequency between different control panels. Stage 2: rs6596473 showed no significant association with AgP in the replication with the German and Dutch case-control samples. After pooling the German AgP populations (674 cases, 2891 controls) to significantly increase the statistical power (SP = 0.81), rs6596473 RA showed significant association with AgP prior to and upon adjustment with the covariates smoking and gender with padj  = 0.005, OR = 1.35. Stage 3: RA of rs6596473 showed no significant association with severe CP. CONCLUSION: SNP rs6596473 of SLC23A1 is suggested to be associated with AgP. These results add to previous reports that vitamin C plays a role in the pathogenesis of periodontitis.

Composition of microbial oral biofilms during maturation in young healthy adults.

In the present study we aimed to analyze the bacterial community structure of oral biofilms at different maturation stages in young healthy adults. Oral biofilms established on membrane filters were collected from 32 human subjects after 5 different maturation intervals (1, 3, 5, 9 and 14 days) and the respective phylogenetic diversity was analyzed by 16S rDNA amplicon sequencing. Our analyses revealed highly diverse entire colonization profiles, spread into 8 phyla/candidate divisions and in 15 different bacterial classes. A large inter-individual difference in the subjects' microbiota was observed, comprising 35% of the total variance, but lacking conspicuous general temporal trends in both alpha and beta diversity. We further obtained strong evidence that subjects can be categorized into three clusters based on three differently occurring and mutually exclusive species clusters.