Effect Of Elastomeric Separator On Microbial Count In Gingival Crevicular Fluid.

BACKGROUND: The separators are a preliminary step for band insertion, but there is a potential risk of bacteraemia during their placement, particularly in susceptible patients. The objective of the study is to determine the effect of separators on the bacterial count in gingival crevicular fluid (GCF) and to assess the efficacy of chlorhexidine mouth rinse and saline irrigation in the reduction of the bacterial count. METHODS: This randomized controlled trial was conducted on 51 participants who were divided into three equal g roups randomly (brushing only/control, saline irrigation, and 2% chlorhexidine mouthwash rinse). The inclusion criteria were age between 18-25 years, good oral hygiene, gingival and plaque index <1, no previous orthodontic treatment, and healthy individuals. The bacterial count was obtained from GCF samples after two hours, on the third day, and on the seventh day. Kruskal Wallis test was used to compare the bacterial count among the three groups, and post hoc analysis was done using Dunn's test. Friedman test was applied to see the difference at three-time points in each group. RESULTS: In both saline and chlorhexidine groups the mean bacterial count decreased significantly from baseline to 3rd day and 7th day after separator placement (p<0.001). For the third day, a significant difference was found in control versus saline and control versus chlorhexidine. No significant difference was found between saline and chlorhexidine on the third day. Similar results were found on the 7 thday. For controls, the bacterial count increased with time and for both saline and chlorhexidine groups the bacterial count decreased. The highest decrease in the bacterial count was found for the chlorhexidine group. CONCLUSIONS: After the placement of separators, there was an increase in the bacterial count in GCF. Notably, chlorhexidine was found to be more effective than saline irrigation in reducing the bacterial count.

Prevalencia de Porphyromonas gingivalis en un grupo de pacientes con aparatología fija de ortodoncia / Prevalence of Porphyromonas gingivalis in a group of patients with fixed orthodontic appliances

Introducción: existen diversos patógenos que pueden afectar no sólo la salud periodontal, sino también la salud general de los pacientes. Objetivo: determinar la Porphyromonas gingivalis (PG) en el primer molar superior derecho de adolescentes, de entre 12 y 18 años, con al menos un mes de tratamiento de ortodoncia con aparatología fija. Material y métodos: se realizó un estudio observacional, descriptivo, transversal de casos en un grupo de 26 adolescentes con tratamiento de ortodoncia, compuesto de brackets metálicos, tubos o bandas, arcos NiTi termoactivos, módulos, cadenas o ligaduras; sin importar sexo, edad, tiempo de tratamiento o maloclusión. Se formaron dos pares de grupos 1 y 2 (15 mujeres y 11 hombres), A y B (13 mujeres y 13 hom- bres) comparando los resultados obtenidos entre los grupos. Resulta- dos: dentro del grupo 1 y 2 la detección molecular de microorganismos arroja que 80% fueron positivas a la PG, 58.33% presenta maloclusión y en promedio 89% de las pacientes son positivas a PG. La detección molecular del grupo A y B indica que 54.54% fueron positivos a PG, mientras que 83.3% presenta maloclusión y en promedio 47% son positivos a PG. Conclusión: la explicación de los eventos moleculares que se desencadenan en la cavidad oral y los sistemas afectados por PG contribuyen a la prevención de complicaciones al tener una mejor comprensión de los fenómenos infecciosos (AU)

Introduction: there are various pathogens that can affect not only periodontal health, but also the general health of patients. Objective: to determine Porphyromonas gingivalis (PG) in the upper right first molar of adolescents, between 12 and 18 years old, with at least one month of orthodontic treatment with fixed appliances. Material and methods: a cross-sectional descriptive observational study of cases was carried out in a group of 26 adolescents with orthodontic treatment, consisting of metal brackets, tubes or bands, thermoactive NiTi archwires, modules, chains or ligatures; regardless of sex, age, treatment time or malocclusion. Two pairs of groups 1 and 2 (15 women and 11 men), A and B (13 women and 13 men) were formed, comparing the results obtained between the groups. Results: within group 1 and 2, the molecular detection of microorganisms shows that 80% were positive for PG, 58.33% presented malocclusion and an average of 89% of patients were positive for PG. The molecular detection of group A and B indicates that 54.54% were positive for PG while 83.3% presented malocclusion and on average 47% were positive for PG. Conclusion: the explanation of the molecular events that are triggered in the oral cavity and the systems affected by PG contribute to the prevention of complications by having a better understanding of the infectious phenomena (AU)

Microbial Screening Reveals Oral Site-Specific Locations of the Periodontal Pathogen Selenomonas noxia.

INTRODUCTION: Selenomonas noxia (SN) is an important periodontal pathogen, associated with gingivitis and periodontitis. Many studies have found associations between SN and indicators of poor health outcomes, such as smoking, low socioeconomic status and obesity. However, less is known about the prevalence of this organism and more specifically about other oral site-specific locations that may harbor this organism. METHODS: Using an existing patient repository (n = 47) of DNA isolated from saliva and other oral sites (n = 235), including the dorsum of the tongue, lower lingual incisor, upper buccal molar and gingival crevicular fluid (GCF), molecular screening for SN was performed. Screening results were analyzed for associations between demographic variables (age, sex, race/ethnicity) and clinical information (body mass index or BMI, presence of orthodontic brackets, primary/mixed/permanent dentition). RESULTS: qPCR screening revealed a total of n = 62/235 sites or 26.3% harboring SN with saliva and GCF (either alone or in combination with one or more sites) most often observed (Saliva, n = 23/27 or 85.18%, GCF, n = 14/27 or 51%). Analysis of site-specific data revealed most positive results were found among saliva and GCF alone or in combination, with fewer positive results observed among the tongue (33.3%), lower lingual incisor (29.6%), and upper buccal molar (25.9%). No significant associations were found between demographic or clinical variables and presence of SN at any site. CONCLUSIONS: These results may be among the first to describe site-specific locations of S. noxia among various additional oral biofilm sites. These data may represent a significant advancement in our understanding of the sites and locations that harbor this organism, which may be important for our understanding of the prevalence and distribution of these organisms among patients of different ages undergoing different types of oral treatments, such as orthodontic treatment or therapy.

Bacteriological Evaluation of Gingival Crevicular Fluid in Teeth Restored Using Fixed Dental Prostheses: An In Vivo Study.

The present in vivo study determined the microbiological counts of the gingival crevicular fluid (GCF) among patients with fixed dental prostheses fabricated using three different techniques. A total of 129 subjects were divided into three study groups: first, cobalt-chrome-based, metal-ceramic prostheses fabricated by the conventional method (MC, n = 35); the second group consisted of cobalt-chrome-based, metal-ceramic prostheses fabricated by the computer-aided design and computer-aided manufacturing (CAD/CAM) technique (CC-MC, n = 35); the third group comprised zirconia-based ceramic prostheses fabricated using the CAD/CAM technique (CC-Zr, n = 35). The control consisted of 24 patients using prostheses fabricated with either MC, CC-MC, or CC-Zr. The GCF was obtained from the subjects before treatment, and 6 and 12 months after the prosthetic treatment. Bacteriological and bacterioscopic analysis of the GCF was performed to analyze the patients' GCF. The data were analyzed using SPSS V20 (IBM Company, Chicago, IL, USA). The number of microorganisms of the gingival crevicular fluid in all groups at 12 months of prosthetic treatment reduced dramatically compared with the data obtained before prosthetic treatment. Inflammatory processes in the periodontium occurred slowly in the case of zirconium oxide-based ceramic constructions due to their biocompatibility with the mucous membranes and tissues of the oral cavity as well as a reduced risk of dental biofilm formation. This should be considered by dentists and prosthodontists when choosing restoration materials for subjects with periodontal pathology.

Microbiota in Gingival Crevicular Fluid Before and After Mechanical Debridement With Antimicrobial Photodynamic Therapy in Peri-Implantitis.

OBJECTIVES: This study aims to compare the microbiota of gingival crevicular fluid (GCF) before and after mechanical debridement (MD) with antimicrobial photodynamic therapy (aPDT) and determine the core efficient microbiota in peri-implantitis after treatment. METHODS: We recruited 9 patients (14 implants) treated with MD+aPDT for peri-implantitis at our center from February 1, 2018, to February 1, 2019. GCF was collected using filter paper strip before and after the treatment. The bacterial 16S rRNA was amplified and sequenced using an Illumina MiSeq platform to characterize the GCF. Bioinformatics and statistical analyses were performed using QIIME2 and R. RESULTS: A total of 4,110,861 high-quality sequences were obtained from GCF samples. Based on the reference database, 1,120 amplicon sequence variants (ASVs) were finally harvested. Principal coordinates analysis indicated significant differences in the bacterial community structure between the 180 days after-treatment group and pre-treatment group. Difference analysis and least discriminant analysis showed that the differences were mainly reflected in non-dominant bacteria between these two groups. The non-dominant genera with significantly different distribution between the 180 days after-treatment group and the pre-treatment group included Lactobacillus, Pedobacter, Bulleidia, Centipeda, Desulfovibrio, Ochrobactrum, Staphylococcus, Microbacterium, Brevundimonas, Desulfobulbus, and Parvimonas. Moreover, a total of 29 predictive functional categories at KEGG level 2 were identified. The significant difference pathways at KEGG level 2 between after-treatment and pre-treatment were concentrated in infectious disease-related pathways. CONCLUSIONS: Patients with peri-implantitis have significant changes in the low-abundance bacteria of the GCF before and after MD+aPDT. MD+aPDT may change the composition of GCF microbiota by increasing the abundance of cluster 1 (beneficial) and decreasing that of cluster 4 (harmful), which may decrease metabolic response to infection and thus improve peri-implantitis.

Defining Metaniches in the Oral Cavity According to Their Microbial Composition and Cytokine Profile.

The human oral microbiota consists of over 700 widespread taxa colonizing the oral cavity in several anatomically diverse oral niches. Lately, sequencing of the 16S rRNA genes has become an acknowledged, culture-independent method to characterize the oral microbiota. However, only a small amount of data are available concerning microbial differences between oral niches in periodontal health and disease. In the context of periodontitis, the cytokine expression in the gingival crevicular fluid has been studied in detail, whereas little is known about the cytokine profile in hard and soft tissue biofilms. In order to characterize oral niches in periodontal health, the oral microbiota and cytokine pattern were analyzed at seven different sites (plaque (P), gingival crevicular fluid (GCF), saliva (S), tongue (T), hard palate (HP), cheek (C) and sublingual area (U)) of 20 young adults using next-generation sequencing and multiplex immunoassays. Site-specific microbial compositions were detected, which clustered into three distinct metaniches ("P-GCF", "S-T-HP" and "C-U") and were associated with niche-/metaniche-specific cytokine profiles. Our findings allow the definition of distinct metaniches according to their microbial composition, partly reflected by their cytokine profile, and provide new insights into microenvironmental similarities between anatomical diverse oral niches.

Treatment of Porphyromonas gulae infection and downstream pathology in the aged dog by lysine-gingipain inhibitor COR388.

COR388, a small-molecule lysine-gingipain inhibitor, is currently being investigated in a Phase 2/3 clinical trial for Alzheimer's disease (AD) with exploratory endpoints in periodontal disease. Gingipains are produced by two species of bacteria, Porphyromonas gingivalis and Porphyromonas gulae, typically associated with periodontal disease and systemic infections in humans and dogs, respectively. P. gulae infection in dogs is associated with periodontal disease, which provides a physiologically relevant model to investigate the pharmacology of COR388. In the current study, aged dogs with a natural oral infection of P. gulae and periodontal disease were treated with COR388 by oral administration for up to 90 days to assess lysine-gingipain target engagement and reduction of bacterial load and downstream pathology. In a 28-day dose-response study, COR388 inhibited the lysine-gingipain target and reduced P. gulae load in saliva, buccal cells, and gingival crevicular fluid. The lowest effective dose was continued for 90 days and was efficacious in continuous reduction of bacterial load and downstream periodontal disease pathology. In a separate histology study, dog brain tissue showed evidence of P. gulae DNA and neuronal lysine-gingipain, demonstrating that P. gulae infection is systemic and spreads beyond its oral reservoir, similar to recent observations of P. gingivalis in humans. Together, the pharmacokinetics and pharmacodynamics of COR388 lysine-gingipain inhibition, along with reduction of bacterial load and periodontal disease in naturally occurring P. gulae infection in the dog, support the use of COR388 in targeting lysine-gingipain and eliminating P. gingivalis infection in humans.

Levels of pro- and anti-inflammatory cytokines in cystic fibrosis patients with or without gingivitis.

BACKGROUND: Inflammatory periodontal diseases are caused by interaction between gram negative, anaerobic bacteria and host response. Persistent infection of Pseudomonas aeruginosa in cystic fibrosis (CF) patients also cause increased pro-inflammatory response and the imbalance of pro- and anti-inflammatory response in brochoalveolar lavage fluid which leads to destruction of lungs. The aim of this study is to evaluate periodontal status of CF patients, to measure level of cytokines and biochemical molecules in gingival crevicular fluid (GCF), and to detect presence of P. aeruginosa in dental plaque samples. MATERIALS AND METHODS: GCF samples were collected from 41 CF patients and 39 healthy (non-CF) subjects. Interleukin (IL)-1ß, IL-17, IL-10, human neutrophil elastase (HNE), cystic fibrosis transmembrane regulator (CFTR) protein, and human ß-defensin-1 (HBD1) in GCF were evaluated by ELISA method. Dental plaque samples were collected from 18 CF patients with history of P. aeruginosa colonization and 15 non-CF subjects. Presence of P. aeruginosa was evaluated by using conventional culture methods and molecular methods. RESULTS: Levels of IL-1ß, HNE, and HBD1 in CF patients were significantly higher than non-CF subjects. However, IL-10 level was significantly lower in CF patients. Increased pro-inflammatory (IL-1ß) and decreased anti-inflammatory (IL-10) cytokine levels were observed in GCF samples from CF patients, irrespective of their periodontal status. P. aeruginosa were detected in four samples of 18 CF patients, and all were negative in non-CF group. CONCLUSIONS: As a result of this study, CF coexists increasing pro-inflammatory and decreasing anti-inflammatory response locally. Due to increasing pro-inflammation, CF patients should be followed-up more often than non-CF children.

Local IL-10 level as a predictive factor in generalized aggressive periodontitis treatment response.

Generalized aggressive periodontitis (GAgP) presents a reduced response to non-surgical therapy. However, it is not clear if the initial clinical, microbiological or immunological characteristics are impacting the worse response to treatment. This study aimed to identify the predictive value of clinical, microbiological and immunological patterns on the clinical response to therapy in GAgP patients. Twenty-four GAgP patients were selected, and gingival crevicular fluid (GCF) and subgingival biofilm were collected. Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Tannerella forsythia levels were evaluated by qPCR, and IL-1ß and IL-10 concentration by ELISA. Twelve patients were treated with SRP (scaling and root planning), and twelve with SRP plus 375 mg amoxicillin and 250 mg metronidazole (8/8 hours, 7 days) (SRP + AM). The clinical changes (Probing Pocket Depth [PPD] reduction and Clinical Attachment Level [CAL] gain) 6 months post-treatment were correlated to the initial clinical, inflammatory and microbiological variables using stepwise logistic regression (α = 5%). CAL gain at 6 months was 1.16 ± 0.77 for SRP and 1.74 ± 0.57 mm for SRP + AM (P > .05). PPD reduction was 1.96 ± 0.82 for SRP and 2.45 ± 0.77 mm for SRP + AM (P < .05). In the SRP group, IL-10 showed a predictive value for clinical response. The higher the IL-10 concentration at baseline, the higher the reduction in PPD at 6 months (P = .01, r = .68). However, when antimicrobials were administered, no significant influence was detected (P > .05). It can be concluded that the IL-10 levels in GFC act as a predictor of clinical response to GAgP. Moreover, the intake of antimicrobials appears to overlap the influence of the inflammatory response on clinical response to treatment. Clinical trial registration number: NCT03933501.

A novel microbiological medium for the growth of periodontitis associated pathogens.

A novel microbiological medium designed to be more representative of gingival crevicular fluid. Chosen representative periodontal microorganisms showed good growth with minimal effect on human cell viability. This will enable more comparisons between different periodontitis associated organisms and their potential role in host health and systemic disease.

Influence of restorative margins position on one-stage laser-microgrooved implants-supported single screwed crowns: A clinical, biochemical, and microbiological analysis.

AIM: To clinically, biochemically, and microbiologically evaluate the influence of crown margins position on one-stage laser-microgrooved implants. MATERIALS AND METHODS: Twenty-one-stage titanium implants with a laser-microgrooved collar surface, supporting screwed, single crown restorations, were placed in 20 partially edentulous patients and evaluated. Clinical parameters included modified plaque index, modified gingival index, peri-implant probing pocket depth, bleeding on probing, and distance between implant shoulder and mucosal margin. The parameters were recorded at baseline (crowns delivery) and at every 6-month recall visit, until the end of the 3 years follow-up period. At the same time intervals, radiographic marginal bone levels were assessed at the mesial and distal aspect of the implant sites. For biochemical analysis, the volume of the peri-implant sulcus fluid, and its levels of interleukin-1beta (IL-1ß), interleukin-6 (IL-6), and of tumor necrosis factor-α, were utilized to evaluate the peri-implant health conditions at the end of the 3-year follow-up period. At the same time, microbiological analysis, including the concentration of five putative periodontal pathogens (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola, and Tannerella forsythensis), were assessed. The crown margins positions were classified into four groups (A = intracrevicular position >2 mm, B = intracrevicular position ≤2 mm/<1 mm, C = intracrevicular position ≤1 mm/<0 mm, and D = extracrevicular position), and the biochemical, and microbiological parameters were evaluated at 3 years. RESULTS: No statistical differences of clinical and biochemical parameters were found between the four groups. In group A, compared to groups B, C, and D, a statistically significant higher concentration of putative periodontal pathogens was found. CONCLUSIONS: Results showed that the intracrevicular deeper position of the restoration margin does not influence the clinical and biochemical peri-implant parameters. The deeper position of the crown margin is associated with a greater amount of putative periodontal pathogenic microflora colonization.

Effect of orthodontic treatment on the subgingival microbiota: A systematic review and meta-analysis.

The aim of this systematic review was to assess qualitative changes induced by fixed appliance orthodontic treatment on the subgingival microbiota. Seven databases were searched up to August 2017 for randomized and nonrandomized clinical studies assessing the effect of orthodontic appliances on the subgingival bacteria in human patients. After elimination of duplicate studies, data extraction and risk of bias assessment according to the Cochrane guidelines, random-effects meta-analyses of relative risks (RR) and their 95% confidence intervals (CIs) were performed. According to controlled studies, the presence of Aggregatibacter actinomycetemcomitans in the subgingival crevicular fluid of orthodontic patients was increased 3-6 months after fixed appliance insertion compared to untreated patients (2 studies; RR = 15.54; 95% CI = 3.19-75.85). There was still increased subgingival prevalence of Aggregatibacter actinomycetemcomitans (3 studies; RR = 3.98; 95% CI = 1.23-12.89) and Tannerella forsythia in orthodontic patients up to 6 months after appliance removal compared to untreated patients. However, caution is warranted due to high risk of bias and imprecision. Insertion of orthodontic fixed appliances seems to be associated with a qualitative change of subgingival microbiota, which reverts to some extent back to normal in the first months after appliance removal. However, there is limited evidence on the timing and extent of these changes.

Differential expressions of biomarkers in gingival crevicular fluid of Han and Uygur populations with peri-implantitis.

This study aims to investigate and compare the biomarkers in the gingival crevicular fluid between the Han and Uygur subjects with healthy implants and peri-implantitis.Totally 80 subjects were divided into the H-case (Han patients with peri-implantitis), U-case (Uygur patients with peri-implantitis), H-control (Han subjects with healthy implants), and U-control (Uygur subjects with healthy implants) groups. Cytokine levels in the gingival crevicular fluid were detected, and the dominant bacteria species were analyzed.The matrix metalloproteinase (MMP)-13 level in the gingival crevicular fluid in the U-control group was significantly higher than the H-control group, whereas the C-reactive protein level in the H-control group was significantly higher than in the U-control group. No significant difference was observed in the dominant subgingival bacteria species between the H- and U-control groups. The levels of interleukin (IL)-1ß and MMP-8 were significantly higher in the H-case group than the U-case group, whereas the IL-17A level in the U-case group was significantly higher. The shared dominant subgingival bacteria species of the case groups mainly included Prevotella, clostridium, Porphyromonas, treponema, Streptococcus, neisseria, and hemophilus. Moreover, Acinetobacter, Micrococcus, and Moraxella were found to be the specific dominant subgingival bacteria species for the U-case group. In addition, compared with the H-case group, the IL-1ß levels were negatively correlated with Acinetobacter, Micrococcus, and Moraxella in the U-case group.Han and Uygur populations with healthy implants and peri-implantitis have differentially expressed cytokines in the gingival crevicular fluid. Moreover, dominant subgingival bacteria species differ between the Han and Uygur populations with peri-implantitis.

An Analytical Method for Assessing Optimal Storage Conditions of Gingival Crevicular Fluid and Disclosing a Peptide Biomarker Signature of Gingivitis by MALDI-TOF MS.

PURPOSE: Gingival crevicular fluid (GCF) is an important diagnostic source of biomarkers for both periodontitis and gingivitis. However, GCF peptide signature may change depending on factors such as handling and storage. Here we propose a standardized methodology for GCF analysis by MALDI-TOF/TOF-MS in order to distinguish a characteristic peptide signature of gingivitis. EXPERIMENTAL DESIGN: The best storage/handling conditions which may ensure the stability of the endogenous peptidome in GCF is determined and then MALDI-TOF MS comparative analysis is performed. Reproducible GCF MALDI-TOF signatures between two groups of gingivitis (n = 10) and healthy (n = 10) subjects are compared. RESULTS: A pattern of five peptides resulted differentially expressed between gingivitis and healthy groups. Interestingly, among these biomarkers the C-terminal fragment of alpha-1-antitrypsin (AAT) namely C-36 peptide and two different PTMs of the full-length S100A9 protein are found. CONCLUSIONS AND CLINICAL RELEVANCE: The method described provides a rapid comparative analysis of GCF signatures between periodontally healthy and gingivitis subjects. A pattern based on the expression of endogenous peptides and their PTMs is identified in GCF as putative biomarkers of gingivitis. These findings improve the knowledge of the inflammatory, immune, and structural substrates which might have a key role in the pathogenesis of gingivitis.

Cytokines and MMPs levels in gingival crevicular fluid from patients with chronic periodontitis before and after non-surgical periodontal therapy

The study of host response in periodontal disease may provide a mechanism to monitor disease progression. the purpose of the present research was to determine the levels of IL-1alfa, IL-1beta, TNF-alfa, IL-6, IL-6sR, IL-8, IL-10, MMP-3 and MMP-8 in gingival crevicular fluid (GCF), before and after non-surgical periodontal treatment (NSPT) in order to evaluate therapy response. methodology: eleven patients diagnosed with chronic periodontitis and eleven healthy subjects were selected for this study. clinical measurements, including probing depth (PD) and clinical attachment loss (CAL) were carried out in patients diagnosed with chronic periodontitis and periodontal healthy controls. the clinical indexes evaluated were: gingival index (GI) and plaque index (PI). samples of GCF were taken from one tooth per quadrant before and 45 days after NSPT. the levels of inflammatory mediators were measured by ELISA. results: the values of all clinical parameters decressed significsntly after treatment. the concentration levels of all cytokines and MMP-3 and MMP-8 in the GCF sample were higher in patients diagnosed with chronic periodontitis compared to the healthy group. all inflammatory mediators decreased after therapy, but did not reach control values; IL-6, Il-6sR, IL-10 and TNF-alfa, attained the highest reduction (70 percent -54 percent); the vales of MMP3, IL-1alfa, IL-1beta and IL-8 were reduced between 50 percent ­ 34 percent; and MMP-8 showed the lowest decrease (28 percent). conclusion: all clinical parameters and cytokines levels decreased after NSPT. the mediators TNF-alfa IL-6, IL-6sR, and IL-10 showed the largest variation between before and after NSPT and could thus be used to evaluate therapy response.

Diversity analysis of subgingival microbial bacteria in peri-implantitis in Uygur population.

This study is to investigate the subgingival bacterial diversity and community structure in the Uygur subjects with peri-implantitis.Totally 40 cases of gingival crevicular fluid were collected from Uygur subjects and divided into the Control group (healthy implants) and Case group (peri-implantitis), respectively. DNA was extracted, and the sequencing in the 16SrRNA V4-V5 region was conducted on the Illumina Miseq sequencing platform. The 16SrRNA gene clone library was constructed and analyzed.Totally 733,759 valid tags were obtained from these 40 samples. After comparing with the Silva-16S database by the Uparse software, 263 operational taxonomic unit were finally harvested (135 for the Control group and 128 for the Case group). The differential bacteria between these 2 groups at the phylum, class, order, family, and genus levels were Actinobacteria, Actinomycetes, Pasteurellales, Moraxellaceae, and Acinetobacter, respectively. The dominant genera with significantly different distribution between the Control and Case groups included Vibrio, Campylobacter, Granulicatella, Acinetobacter, Micrococcus, and Moraxella. The α diverstiy analysis based on the chao diversity index showed that there was significant difference in the microbiological diversity between these 2 groups. Principal coordinates analysis analysis indicated significant differences in the bacterial community structure between these 2 groups. Cluster analysis showed higher abundance of Micrococcus in the Case group, while higher abundance of Prevotella in the Control group.There are significant differences in the diversity of subgingival bacteria between the Uygur subjects with healthy implants and peri-implantitis. Moraxella, Micrococcus, and Acinetobacter might represent dominant bacteria genera causing peri-implantitis in the Uygur population.

Intraoral versus extraoral cementation of implant-supported single crowns: Clinical, biomarker, and microbiological comparisons.

OBJECTIVES: Implant supported single metal-ceramic crowns cemented either extraorally or intraorally were comparatively evaluated by clinical, radiologic, biomarker, and microbiological parameters. MATERIALS AND METHODS: Twelve patients with bilateral single tooth gap in the maxillary posterior region received two locking-taper implants; 4.5 mm width, 8 mm length. Selection of intraoral (IOC) or extraoral cementation (EOC) using screwless titanium abutments was done randomly. Peri-implant crevicular fluid (PICF), gingival crevicular fluid (GCF) samples were collected from the implants, adjacent teeth, and bleeding on probing, soft tissue thickness, keratinized tissue width were recorded before starting the prosthetic procedures (baseline) and 3, 6 months after implant loading. Crestal bone loss was measured on radiographs taken immediately and 6 months after cementation. Cytokine levels, amounts of bacteria were determined in PICF/GCF samples. Data were tested by appropriate statistical analyses. RESULTS: Clinical findings were similar in the crowns cemented extraorally or intraorally at all times (P < .05). PICF and GCF data were similar. At 3 month, interleukin-17E and osteoprotegerin levels were lower in the intraorally cemented crowns. CONCLUSION: Extraorally and intraorally cemented crowns exhibited similar crestal bone loss after loading. Higher amount of osteoprotegerin at 3 month at the EOC than the IOC sites might bode well for good osseointegration.

The periodontal pocket.

Periodontal disease is synonymous with the presence of periodontal pockets, and very often the clinical success of periodontal therapy is based on periodontal pocket depth reduction. Therefore, in the fields of periodontology and implant dentistry, significant research effort has been placed on the etiopathogenesis, diagnosis and treatment of periodontal/peri-implant disease and as a consequence on pocket pathology. In this volume of Periodontology 2000, the in-depth reviews include topics ranging from preclinical models, anatomy and structure of tissues, and molecular and bacterial components, to treatments of pockets around teeth and implants. These reviews aim to provide the readers with current and future perspectives on the different areas of research into the periodontal pocket.

Association of Distinct Fine Specificities of Anti-Citrullinated Peptide Antibodies With Elevated Immune Responses to Prevotella intermedia in a Subgroup of Patients With Rheumatoid Arthritis and Periodontitis.

OBJECTIVE: In addition to the long-established link with smoking, periodontitis (PD) is a risk factor for rheumatoid arthritis (RA). This study was undertaken to elucidate the mechanism by which PD could induce antibodies to citrullinated peptides (ACPAs), by examining the antibody response to a novel citrullinated peptide of cytokeratin 13 (CK-13) identified in gingival crevicular fluid (GCF), and comparing the response to 4 other citrullinated peptides in patients with RA who were well-characterized for PD and smoking. METHODS: The citrullinomes of GCF and periodontal tissue from patients with PD were mapped by mass spectrometry. ACPAs of CK13 (cCK13), tenascin-C (cTNC5), vimentin (cVIM), α-enolase (CEP-1), and fibrinogen ß (cFIBß) were examined by enzyme-linked immunosorbent assay in patients with RA (n = 287) and patients with osteoarthritis (n = 330), and cross-reactivity was assessed by inhibition assays. RESULTS: A novel citrullinated peptide cCK13-1 (444 TSNASGR-Cit-TSDV-Cit-RP458 ) identified in GCF exhibited elevated antibody responses in RA patients (24%). Anti-cCK13-1 antibody levels correlated with anti-cTNC5 antibody levels, and absorption experiments confirmed this was not due to cross-reactivity. Only anti-cCK13-1 and anti-cTNC5 were associated with antibodies to the periodontal pathogen Prevotella intermedia (P = 0.05 and P = 0.001, respectively), but not with antibodies to Porphyromonas gingivalis arginine gingipains. Levels of antibodies to CEP-1, cFIBß, and cVIM correlated with each other, and with smoking and shared epitope risk factors in RA. CONCLUSION: This study identifies 2 groups of ACPA fine specificities associated with different RA risk factors. One is predominantly linked to smoking and shared epitope, and the other links anti-cTNC5 and cCK13-1 to infection with the periodontal pathogen P intermedia.

The correlation between periodontal health status and suspectibility to infections associated with craniomaxillofacial osteosynthesis plates.

AIM: The aim of the present study was to demonstrate the possible relation between periodontal health status and infections associated with osteosynthesis materials (OMs) used in the oral and maxillofacial reconstruction. MATERIAL AND METHODS: The study group consisted of 32 individuals which were subdivided into two groups regarding their PSI scores. After the removal of the osteosynthesis plates, microbial colonization was assessed via microbiological cultivation, fluorescence microscopy and scanning electron microscopy. In addition, samples obtained from gingival crevicular fluids were investigated by fluorescence microscopy. RESULTS: A total of 118 osteosynthesis plates were examined. 8.5% (n = 10) of the plates were associated at least one of the clinical signs of infection. There was a positive correlation between periodontal disease and clinical signs of infection (p = 0.022). Patients with infection signs also had a higher number of smoking history (pack years, p = 0.010). Intraorally placed osteosynthesis plates showed wide range of bacterial colonizations compared to extraorally inserted osteosynthesis materials (p = 0.004). CONCLUSION: Patients with poor periodontal health might be potential candidates for OM related infections. Early removal of OMs in patients with poor periodontal health status and/or heavy smokers would have clinical benefits. In addition, preferation of extraoral access to the fracture line might decrease the possibility of plate related infections.