Periodontitis, Edentulism, and Risk of Mortality: A Systematic Review with Meta-analyses.

Periodontitis has been independently associated with the chronic noncommunicable diseases that most frequently lead to death worldwide. The aim of the present systematic review was to study whether people with periodontitis/edentulism are at increased risk of all-cause and cause-specific mortality as compared with those without periodontitis/edentulism. Cohort studies were included that 1) evaluated periodontitis or edentulism as exposures in relation to all-cause or cause-specific mortality as an outcome and 2) reported effect estimates as hazard ratios, risk ratios, or odds ratios with 95% CIs or crude numbers. Two review authors independently searched for eligible studies, screened the titles and abstracts, did full-text analysis, extracted the data from the published reports, and performed the risk-of-bias assessment. In case of disagreement, a third review author was consulted. Study results were summarized through random effects meta-analyses. A total of 57 studies were included, involving 48 cohorts and 5.71 million participants. Periodontitis was associated with increased risk of all-cause mortality (risk ratio, 1.46 [95% CI, 1.15 to 1.85]) and mortality due to cardiovascular diseases (1.47 [1.14 to 1.90]), cancer (1.38 [1.24 to 1.53]), coronary heart disease (2.58 [2.20 to 3.03]), cerebrovascular diseases (3.11 [2.42 to 3.98]), but not pneumonia (0.98 [0.69 to 1.38]). Edentulism (all types) was associated with increased risk of all-cause mortality (1.66 [1.46 to 1.88]) and mortality due to cardiovascular diseases (2.03 [1.50 to 2.74]), cancer (1.55 [1.24 to 1.94]), pneumonia (1.72 [1.07 to 2.78]), coronary heart disease (2.98 [2.43 to 3.65]), and cerebrovascular diseases (3.18 [2.24 to 4.51]). Periodontitis and its ultimate sequela (edentulism) are associated with an increased risk of all-cause and cause-specific mortality (PROSPERO CRD42018100095).

Antimicrobial effect of nanostructured membranes for guided tissue regeneration: an in vitro study.

OBJECTIVE: The purpose of this in vitro study was to evaluate the antibacterial effect of a novel non-resorbable, bioactive polymeric nanostructured membrane (NMs), when doped with zinc, calcium and doxycycline. METHODS: A validated in vitro subgingival biofilm model with six bacterial species (Streptococcus oralis, Actinomyces naeslundii, Veillonela parvula, Fusobacterium nucleatum, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans) was used. The experimental NMs, with and without being doped with doxycycline, calcium and zinc, were placed on hydroxyapatite (HA) discs. As positive control membranes, commercially available dense polytetrafluoroethylene (d-PTFE) membranes were used and, as negative controls, the HA discs without any membrane. The experimental, positive and negative control discs were exposed to a mixed bacterial suspension, at 37 °C under anaerobic conditions, during 12, 24, 48 and 72 h. The resulting biofilms were analyzed through scanning electron microscopy (SEM), to study their structure, and by quantitative polymerase chain reaction (qPCR), to assess the bacterial load, expressed as colony forming units (CFU) per mL. Differences between experimental and control groups were evaluated with the general linear model and the Bonferroni adjustment. RESULTS: As shown by SEM, all membrane groups, except the NMs with doxycycline, resulted in structured biofilms from 12-72 hours. Similarly, only the membranes loaded with doxycycline demonstrated a significant reduction in bacterial load during biofilm development, when compared with the control groups (p < 0.001). SIGNIFICANCE: Doxycycline-doped nanostructured membranes have an impact on biofilm growth dynamics by significant reducing the bacterial load.

In vitro biofilm formation on different ceramic biomaterial surfaces: Coating with two bactericidal glasses.

OBJECTIVES: To compare biofilm formation on the surface of different ceramic biomaterials to be used in implant dentistry. METHODS: In vitro biofilm formation was investigated from mixtures of standard reference strains of Streptococcus oralis, Veillonella parvula, Actinomyces naeslundii, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis. Sterile ceramic calcium hydroxyapatite discs (HA) as control, sterile Al2O3/Ce-TZP nanocomposite sandblasted discs (material A1) and sterile Al2O3/Ce-TZP nanocomposite sandblasted discs and coated with two types of antimicrobial glasses (materials A2 and A3) were used. Biofilms were grown on the four surfaces and evaluated after 12, 24, 48 and 72 h of incubation. Biofilms were examined by confocal laser scanning microscopy (CLSM). In addition, counts of live bacterial cells of the target species A. actinomycetemcomitans, F. nucleatum and P. gingivalis were calculated by quantitative polymerase chain reaction (qPCR) combined with propidium monoazide (PMA). For data analysis, bacterial counts were compared with a multivariate general lineal model. RESULTS: Using CLSM, cell vitality decreased in A2 and A3. With qPCR-PMA, significant differences in vitality were observed forA. actinomycetemcomitans in A3 after 48 and 72 h of incubation. With respect to the development of the biofilms, a significant increase in counts on HA and materials A1 and A2 was observed for A. actinomycetemcomitans and F. nucleatum. Conversely, for P. gingivalis, no differences were found for HA and materials A1 and A2. SIGNIFICANCE: Differences in biofilm formation were detected among the different tested materials. The ceramic material A3 has an effect on the vitality of A. actinomycetemcomitans growing in an in vitro biofilm model.

Prevalence of oral side effects of chemotherapy and its relationship with periodontal risk: a cross sectional study.

PURPOSE: To determine the prevalence of professionally reported oral side effects of chemotherapy and the self-reported oral side effects and whether both prevalences could be related to the periodontal risk of the patients. METHODS: A cross-sectional study with patients undergoing chemotherapy treatment was carried out. Demographic, oral hygiene habits, and cancer-related data were collected while the patient was receiving the chemotherapy infusion. Patient's oral status, measured according to the oral-assessment guide for patients in hospital environments, patient-related outcomes (PROMs), measured by a visual analogue scale, and patient's periodontal risk were analyzed using validated questionnaires. Data was reported in means and standard deviations (SD) in quantitative variables and in counts, prevalence, and 95% confidence intervals (CI) in qualitative variables. ANOVA test and chi-squared tests were used to compare oral side effects among different periodontal risk groups. RESULTS: Three hundred sixty-nine patients were included in the study. The prevalence of professionally reported oral side effects was 86.99% (95% confidence interval CI 83.54%; 90.44%). The prevalence of self-reported oral side effects was 89.70% (95% CI 86.59; 92.82). The most common oral side effects were xerostomia (73.4%), dysgeusia (61.8%), and dry lips (54.2%). More oral alterations were found in patients with worse periodontal risk (p < 0.001). CONCLUSIONS: The prevalence of oral side effects (professional or self-reported) is higher than 85% in patients undergoing chemotherapy. This prevalence increases as the risk of developing periodontal disease does.

Antibacterial effects of polymeric PolymP-n Active nanoparticles. An in vitro biofilm study.

OBJECTIVE: to study the antibacterial effect of polymeric PolymP-n Active nanoparticles using an in vitro subgingival biofilm model. METHODS: Hydroxyapatite discs coated with five modalities of nanoparticles (NPs): NPs, NPs doped with zinc, calcium, silver and doxycycline, PBS as control, and Streptococcus oralis, Actinomyces naeslundii, Veillonella parvula, Fusobacterium nucleatum, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans were studied in a static in vitro biofilm model (12, 24, 48, and 72h). Nano-roughness of the different disc surfaces (SRa, in nm) and morphological characteristic of the biofilms (thickness (µm) and bacterial viability) were studied by different microscopy modalities. Quantitative Polymerase Chain Reaction was used to assess the effect of the nanoparticles on the bacterial load (colony forming unit per milliliter) (CFUmL-1). Analysis of variance and post-hoc testing with T3 Dunnett́s, and Student Newman Keuls correction was used. Results were considered statistically significant at p<0.05. RESULTS: Surfaces containing the different nanoparticles showed significant increments in roughness when compared to controls (p<0.05). A similar biofilm formation and dynamics was observed, although reductions in bacterial viability were detected in biofilms in contact with the different nanoparticles, more pronounced with silver and doxycycline NPs. Doxycycline-NPs biofilms resulted in unstructured biofilm formation and significantly lower number of the six species when compared with the other nanoparticles specimens and controls (p<0.001 in all cases). SIGNIFICANCE: Polymeric PolymP-n Active nanoparticles when combined with silver and doxycycline showed a significant antibacterial effect when tested in an in vitro subgingival biofilm model.

Validation of a multiplex qPCR assay for the identification and quantification of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis: In vitro and subgingival plaque samples.

OBJECTIVE: To validate a multiplex qPCR (m-qPCR) assay for the simultaneous identification and quantification of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis in subgingival samples. MATERIAL AND METHODS: In vitro samples: DNA combinations of A. actinomycetemcomitans and P. gingivalis in similar or different concentrations were prepared. qPCR and m-qPCR were performed using the same primers and hydrolysis probes specific for 16SrRNA genes. Results were analyzed using intra-class (ICCs) and Lin's correlation coefficients (r) based on quantification cycle (Cq) values. Subgingival plaque samples: a cross-sectional study analyzing subgingival plaque samples harvested from periodontally-healthy and chronic periodontitis patients. Samples were processed by either qPCR or m-qPCR targeting both bacteria. Sensitivity, specificity, predictive values and Lins correlation coefficients (r) were calculated using CFU/mL as primary outcome. RESULTS: In vitro samples: m-qPCR yielded a good reproducibility (coefficients of variation around 1% and ICCs > 0.99) for both bacterial species. m-qPCR achieved detection limits and specificity similar to qPCR. An excellent concordance (r = 0.99) was observed between m-qPCR and qPCR for A. actinomycetemcomitans and P. gingivalis without statistical significant differences between both methods Subgingival plaque samples: a high sensitivity (above 80%) and specificity (100%) was obtained with the m-qPCR for both bacteria. The m-qPCR yielded a good concordance in Cq values, showing a good level of agreement between qPCR and m-qPCR. CONCLUSION: The tested m-qPCR method was successful in the simultaneous quantification of A. actinomycetemcomitans and P. gingivalis, with a high degree of sensitivity and specificity on subgingival plaque samples.

Comparative gene expression analysis of Porphyromonas gingivalis ATCC 33277 in planktonic and biofilms states.

BACKGROUND AND OBJECTIVE: Porphyromonas gingivalis is a keystone pathogen in the onset and progression of periodontitis. Its pathogenicity has been related to its presence and survival within the subgingival biofilm. The aim of the present study was to compare the genome-wide transcription activities of P. gingivalis in biofilm and in planktonic growth, using microarray technology. MATERIAL AND METHODS: P. gingivalis ATCC 33277 was incubated in multi-well culture plates at 37°C for 96 hours under anaerobic conditions using an in vitro static model to develop both the planktonic and biofilm states (the latter over sterile ceramic calcium hydroxyapatite discs). The biofilm development was monitored by Confocal Laser Scanning Microscopy (CLSM) and Scanning Electron Microscopy (SEM). After incubation, the bacterial cells were harvested and total RNA was extracted and purified. Three biological replicates for each cell state were independently hybridized for transcriptomic comparisons. A linear model was used for determining differentially expressed genes and reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to confirm differential expression. The filtering criteria of ≥ ±2 change in gene expression and significance p-values of <0.05 were selected. RESULTS: A total of 92 out of 1,909 genes (4.8%) were differentially expressed by P. gingivalis growing in biofilm compared to planktonic. The 54 up-regulated genes in biofilm growth were mainly related to cell envelope, transport, and binding or outer membranes proteins. Thirty-eight showed decreased expression, mainly genes related to transposases or oxidative stress. CONCLUSION: The adaptive response of P. gingivalis in biofilm growth demonstrated a differential gene expression.

Response to antiseptic agents of periodontal pathogens in in vitro biofilms on titanium and zirconium surfaces.

OBJECTIVE: The aim of this study was to develop in vitro biofilms on SLA titanium (Ti-SLA) and zirconium oxide (ZrO2) surfaces and to evaluate the effect of antiseptic agents on the number of putative periodontal pathogenic species. METHODS: An in vitro biofilm model was developed on sterile discs of Ti-SLA and ZrO2. Three antiseptic agents [chlorhexidine and cetyl-pyridinium-chloride (CHX/CPC), essential oils (EEOOs) and cetyl-peridinium-chloride (CPC)] were applied to 72-h biofilms, immersing discs during 1min in the antiseptic solution, either with or without mechanical disruption. Viable bacteria [colony forming units (CFU/mL)] were measured by quantitative polymerase chain reaction (qPCR) combined with propidium monoazide. A generalized lineal model was constructed to determine the effect of the agents on the viable bacterial counts of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Fusobacterium nucleatum on each surface. RESULTS: The exposure to each antiseptic solution resulted in a statistically significant reductions in the number of viable target species included in the in vitro multi-species biofilm, on both Ti-SLA and ZrO2 (p<0.001) which was of up to 2 orders for A. actinomycetemcomitans, for P. gingivalis 2 orders on Ti-SLA and up to 3 orders on ZrO2, and, for F. nucleatum up to 4 orders. No significant differences were found in counts of the tested bacteria between in vitro biofilms formed on both Ti-SLA and ZrO2, after topically exposure to the antimicrobial agents whether the application was purely chemical or combined with mechanical disruption. SIGNIFICANCE: A. actinomycetemcomitans, P. gingivalis and F. nucleatum responded similarly to their exposure to antiseptics when grown in multispecies biofilms on titanium and zirconium surfaces, in spite of the described structural differences between these bacterial communities.

Comparison of the detection of periodontal pathogens in bacteraemia after tooth brushing by culture and molecular techniques.

BACKGROUND: The prevalence and amounts of periodontal pathogens detected in bacteraemia samples after tooth brushing-induced by means of four diagnostic technique, three based on culture and one in a molecular-based technique, have been compared in this study. MATERIAL AND METHODS: Blood samples were collected from thirty-six subjects with different periodontal status (17 were healthy, 10 with gingivitis and 9 with periodontitis) at baseline and 2 minutes after tooth brushing. Each sample was analyzed by three culture-based methods [direct anaerobic culturing (DAC), hemo-culture (BACTEC), and lysis-centrifugation (LC)] and one molecular-based technique [quantitative polymerase chain reaction (qPCR)]. With culture any bacterial isolate was detected and quantified, while with qPCR only Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans were detected and quantified. Descriptive analyses, ANOVA and Chi-squared tests, were performed. RESULTS: Neither BACTEC nor qPCR detected any type of bacteria in the blood samples. Only LC (2.7%) and DAC (8.3%) detected bacteraemia, although not in the same patients. Fusobacterium nucleatum was the most frequently detected bacterial species. CONCLUSIONS: The disparity in the results when the same samples were analyzed with four different microbiological detection methods highlights the need for a proper validation of the methodology to detect periodontal pathogens in bacteraemia samples, mainly when the presence of periodontal pathogens in blood samples after tooth brushing was very seldom.

Effectiveness of Lateral Bone Augmentation on the Alveolar Crest Dimension: A Systematic Review and Meta-analysis.

Lateral ridge augmentation procedures are aimed to reconstruct deficient alveolar ridges or to build up peri-implant dehiscence and fenestrations. The objective of this systematic review was to assess the efficacy of these interventions by analyzing data from 40 clinical studies evaluating bone augmentation through either the staged or the simultaneous approach. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guideline for systematic reviews was used. The primary outcomes were the changes at reentry, in the ridge width, and in the vertical and horizontal dimensions of the peri-implant defect, measured in millimeters, in the staged and simultaneous approaches, respectively. The results of the meta-analysis showed, for the simultaneous approach, a statistically significant defect height reduction when all treatments were analyzed together (weighted mean difference [WMD] = -4.28 mm; 95% confidence interval: [CI] -4.88, -3.69; P < 0.01). The intervention combining bone replacement grafts with barrier membranes was associated with superior outcomes The most frequently used intervention was the combination of xenograft and bioabsorbable membrane. Similarly, for the staged approach, there was a statistically significant horizontal gain when all treatment groups were combined (WMD = 3.90 mm; 95% CI: 3.52, 4.28; P < 0.001). The most frequently used intervention was the use of autogenous bone blocks. Both treatment strategies led to high survival and success rates (>95%) for the implants placed on the regenerated sites. Nonexposed sites gained significantly more in the simultaneous and staged approaches (WMD = 1.1 and 3.1 mm).

An in vitro biofilm model associated to dental implants: structural and quantitative analysis of in vitro biofilm formation on different dental implant surfaces.

OBJECTIVES: The impact of implant surfaces in dental biofilm development is presently unknown. The aim of this investigation was to assess in vitro the development of a complex biofilm model on titanium and zirconium implant surfaces, and to compare it with the same biofilm formed on hydroxyapatite surface. METHODS: Six standard reference strains were used to develop an in vitro biofilm over sterile titanium, zirconium and hydroxyapatite discs, coated with saliva within the wells of pre-sterilized polystyrene tissue culture plates. The selected species used represent initial (Streptococcus oralis and Actinomyces naeslundii), early (Veillonella parvula), secondary (Fusobacterium nucleatum) and late colonizers (Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans). The developed biofilms (growth time 1 to 120h) were studied with confocal laser scanning microscopy using a vital fluorescence technique and with low-temperature scanning electron microscopy. The number (colony forming units/biofilm) and kinetics of the bacteria within the biofilm were studied with quantitative PCR (qPCR). As outcome variables, the biofilm thickness, the percentage of cell vitality and the number of bacteria were compared using the analysis of variance. RESULTS: The bacteria adhered and matured within the biofilm over the three surfaces with similar dynamics. Different surfaces, however, demonstrated differences both in the thickness, deposition of the extracellular polysaccharide matrix as well as in the organization of the bacterial cells. SIGNIFICANCE: While the formation and dynamics of an in vitro biofilm model was similar irrespective of the surface of inoculation (hydroxyapatite, titanium or zirconium), there were significant differences in regards to the biofilm thickness and three-dimensional structure.

Quantitative real-time PCR combined with propidium monoazide for the selective quantification of viable periodontal pathogens in an in vitro subgingival biofilm model.

BACKGROUND AND OBJECTIVES: Differentiation of live and dead cells is an important challenge when using molecular diagnosis for microbial identification. This is particularly relevant when bacteria have been exposed to antimicrobial agents. The objective of this study was to test a method using quantitative real-time polymerase chain reaction (qPCR) combined with propidium monoazide (PMA), developed for the selective quantification of viable P. gingivalis, A. actinomycetemcomitans, F. nucleatum and total bacteria in an in vitro biofilm model after antimicrobial treatment. MATERIAL AND METHODS: PMA-qPCR method was tested in an in vitro biofilm model, using isopropyl alcohol as the antimicrobial agent. Matured biofilms were exposed for 1, 5, 10 and 30 min to isopropyl alcohol by immersion. Biofilms were disrupted and PMA added (final concentration of 100 µm). After DNA isolation, qPCR was carried out using specific primers and probes for the target bacteria. The differentiation of live and dead cells was tested by analysis of variance. RESULTS: When PMA was used in the presence of viable target bacterial cells, no statistically significant inhibition of qPCR amplification was detected (p > 0.05 in all cases). Conversely, after immersion in isopropyl alcohol of the biofilm, PMA resulted in a significant total reduction of qPCR amplification of about 4 log10 . P. gingivalis showed a vitality reduction in the biofilm of 3 log10 , while A. actinomycetemcomitans and F. nucleatum showed a 2 log10 reduction. CONCLUSION: These results demonstrate the efficiency of PMA for differentiating viable and dead P. gingivalis, A. actinomycetemcomitans and F. nucleatum cells, as well as total bacteria, in an in vitro biofilm model, after being exposed to an antimicrobial agent. Hence, this PMA-qPCR method may be useful for studying the effect of antimicrobial agents aimed at oral biofilms.

Analysis of viable vs. dead Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis using selective quantitative real-time PCR with propidium monoazide.

BACKGROUND AND OBJECTIVES: One of the major disadvantages of DNA-based microbial diagnostics is their inability to differentiate DNA between viable and dead microorganisms, which could be important when studying etiologically relevant pathogens. The aim of this investigation was to optimize a method for the selective detection and quantification of only viable Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis cells by combining quantitative real-time polymerase chain reaction (qPCR) and propidium monoazide (PMA). MATERIAL AND METHODS: Three different concentrations of PMA (10, 50 or 100 µm) were added to suspensions of 10(6) (CFU)/mL of viable/dead A. actinomycetemcomitans and P. gingivalis cells. After DNA isolation, qPCR was carried out using specific primers and probes for the tested bacteria. PMA was further tested with different mixtures containing varying ratios of viable and dead cells. The efficacy of PMA to detect viable/dead cells was tested by analysis of variance. RESULTS: For these specific bacterial pathogens, 100 µm PMA resulted in a significant reduction of qPCR amplification with dead cells (10(6) CFU/mL), while with viable cells no significant inhibition was detected. PMA was also effective in detecting selectively viable cells by qPCR detection, when mixtures of varying ratios of viable and dead bacteria were used. CONCLUSIONS: This study demonstrated the efficiency of PMA for differentiating viable and dead A. actinomycetemcomitans and P. gingivalis cells. This method of PMA-qPCR may be useful for monitoring new antimicrobial strategies and for assessing the pathogenic potential of A. actinomycetemcomitans and P. gingivalis in different oral conditions when using molecular diagnostic methods.

[From knowledge of bacterial etiology to the treatment and prevention of the most prevalent infections in the community: odontological infections]. / Del conocimiento de la etiologia bacteriana al tratamiento y la prevencion de las infecciones mas prevalentes en la comunidad: las infecciones odontologicas.

The prevalence of community odontological infections and their relevance to public health were reviewed. Knowledge of bacterial etiology (and the transmittability of these microbial agents) was used to study the disease (individual susceptibility to etiological agents) in order to review the effect of treatment on odontological pathogens and human microbials. The synergy between the primary care physician and the dentist is fundamental to the control of this endemic disease.

Del conocimiento de la etiología bacteriana al tratamiento y la prevención de las infecciones más prevalentes en la comunidad: las infecciones odontológicas / From knowledge of bacterial etiology to the treatment and prevention of the most prevalent infections in the community: odontological infections

Se revisan las infecciones odontológicas desde un punto de vista de las enfermedades infecciosas comunitarias a partir de su prevalencia eimportancia desde la perspectiva de salud pública. Partiendo del conocimiento de la etiología bacteriana (y de la transmisibilidad de estosagentes microbianos) llegamos a la enfermedad (susceptibilidad individual a los agentes etiológicos), para revisar los efectos del tratamientosobre los patógenos odontológicos y la microbiota humana. La sinergia entre el médico de Atención Primaria y el odontólogo es fundamentalen el control de esta endemia

The prevalence of community odontological infections and their relevance to public health were reviewed. Knowledge of bacterial etiology(and the transmittability of these microbial agents) was used to study the disease (individual susceptibility to etiological agents) in order toreview the effect of treatment on odontological pathogens and human microbials. The synergy between the primary care physician and thedentist is fundamental to the control of this endemic disease