Objective
To critically evaluate the existing literature on acute lesions occurring in the periodontium (periodontal abscesses PA, necrotizing periodontal diseases NPD, and endo‐periodontal lesions ...EPL) to determine the weight of evidence for the existence of specific clinical conditions that may be grouped together according to common features. The ultimate goal is to support an objective classification system.
Importance
Although PA, NPD, and EPL occur with relatively low frequency, these lesions are of clinical relevance, because they require immediate management and might severely compromise the prognosis of the tooth.
Findings
In general, the evidence available to define these three conditions was considered limited. PA and EPL are normally associated with deep periodontal pockets, bleeding on probing, suppuration, and almost invariably, with pain. EPL are also associated with endodontic pathology. NPDs have three typical features: pain, bleeding, and ulceration of the gingival interdental papilla. The available data suggested that the prognosis of PA and EPL are worse in periodontitis than in nonperiodontitis patients. Lesions associated with root damage, such as fractures and perforations, had the worst prognosis. NPD progression, extent and severity mainly depended on host‐related factors predisposing to these diseases.
Conclusions
PA should be classified according to the etiological factors involved, with the most frequent being those occurring in pre‐existing periodontal pockets. NPD are clearly associated with the host immune response, which should be considered in the classification system for these lesions. EPLs should be classified according to signs and symptoms that have direct impact on their prognosis and treatment, such as presence or absence of fractures and perforations, and presence or absence of periodontitis.
Objective
To critically evaluate the existing literature on acute lesions occurring in the periodontium (periodontal abscesses PA, necrotizing periodontal diseases NPD, and endo‐periodontal lesions ...EPL) to determine the weight of evidence for the existence of specific clinical conditions that may be grouped together according to common features. The ultimate goal is to support an objective classification system.
Importance
Although PA, NPD, and EPL occur with relatively low frequency, these lesions are of clinical relevance, because they require immediate management and might severely compromise the prognosis of the tooth.
Findings
In general, the evidence available to define these three conditions was considered limited. PA and EPL are normally associated with deep periodontal pockets, bleeding on probing, suppuration, and almost invariably, with pain. EPL are also associated with endodontic pathology. NPDs have three typical features: pain, bleeding, and ulceration of the gingival interdental papilla. The available data suggested that the prognosis of PA and EPL are worse in periodontitis than in nonperiodontitis patients. Lesions associated with root damage, such as fractures and perforations, had the worst prognosis. NPD progression, extent and severity mainly depended on host‐related factors predisposing to these diseases.
Conclusions
PA should be classified according to the etiological factors involved, with the most frequent being those occurring in pre‐existing periodontal pockets. NPD are clearly associated with the host immune response, which should be considered in the classification system for these lesions. EPLs should be classified according to signs and symptoms that have direct impact on their prognosis and treatment, such as presence or absence of fractures and perforations, and presence or absence of periodontitis.
The starting point for defining effective treatment protocols is a clear understanding of the etiology and pathogenesis of a condition. In periodontal diseases, this understanding has been hindered ...by a number of factors, such as the difficulty in differentiating primary pathogens from nonpathogens in complex biofilm structures. The introduction of DNA sequencing technologies, including taxonomic and functional analyses, has allowed the oral microbiome to be investigated in much greater breadth and depth. This article aims to compile the results of studies, using next‐generation sequencing techniques to evaluate the periodontal microbiome, in an attempt to determine how far the knowledge provided by these studies has brought us in terms of influencing the way we treat periodontitis. The taxonomic data provided, to date, by published association and elimination studies using next‐generation sequencing confirm previous knowledge on the role of classic periodontal pathogens in the pathobiology of disease and include new species/genera. Conversely, species and genera already considered as host‐compatible and others less explored were associated with periodontal health as their levels were elevated in healthy individuals and increased after therapy. Functional and transcriptomic analyses also demonstrated that periodontal biofilms are taxonomically diverse, functionally congruent, and highly cooperative. Very few interventional studies to date have examined the effects of treatment on the periodontal microbiome, and such studies are heterogeneous in terms of design, sample size, sampling method, treatment provided, and duration of follow‐up. Hence, it is still difficult to draw meaningful conclusions from them. Thus, although OMICS knowledge has not yet changed the way we treat patients in daily practice, the information provided by these studies opens new avenues for future research in this field. As new pathogens and beneficial species become identified, future randomized clinical trials could monitor these species/genera more comprehensively. In addition, the metatranscriptomic data, although still embryonic, suggest that the interplay between the host and the oral microbiome may be our best opportunity to implement personalized periodontal treatments. Therapeutic schemes targeting particular bacterial protein products in subjects with specific genetic profiles, for example, may be the futuristic view of enhanced periodontal therapy.
Objectives
To test the role of exopolysaccharide (EPS) polymers matrix to modulate the composition/virulence of biofilms growing on titanium (Ti) surfaces, the effect on antibiotic susceptibility, ...and whether a dual‐targeting therapy approach for disrupted EPS matrix could improve the antimicrobial effect.
Materials and Methods
A microcosm biofilm model using human saliva as inoculum was used, and the microbial composition was assessed by checkerboard DNA–DNA hybridization. EPS‐enriched biofilms virulence was tested using fibroblast monolayer. Povidone‐iodine (PI) was used as EPS‐targeting agent followed by amoxicillin + metronidazole antibiotic to reduce bacterial biomass using an in situ model.
Results
An EPS‐enriched environment, obtained by sucrose exposure, promoted bacterial accumulation and led to a dysbiosis on biofilms, favoring the growth of Streptococcus, Fusobacterium, and Campylobacter species and even strict anaerobic species related to peri‐implant infections, such as Porphyromonas gingivalis and Tannerella forsythia (~3‐fold increase). EPS‐enriched biofilm transitioned from a commensal aerobic to a pathogenic anaerobic profile. EPS increased biofilm virulence promoting higher host cell damage and reduced antimicrobial susceptibility, but the use of a dual‐targeting approach with PI pre‐treatment disrupted EPS matrix scaffold, increasing antibiotic effect on in situ biofilms.
Conclusion
Altogether, our data provide new insights of how EPS matrix creates an environment that favors putative pathogens growth and shed light to a promising approach that uses matrix disruption as initial step to potentially improve implant‐related infections treatment.
Titanium particles and ions favor dysbiosis in oral biofilms Souza, João G. S.; Costa Oliveira, Bárbara E.; Bertolini, Martinna ...
Journal of periodontal research,
April 2020, 2020-Apr, 2020-04-00, 20200401, Volume:
55, Issue:
2
Journal Article
Peer reviewed
Objective
To evaluate the effect of titanium (Ti) particles and ions on oral biofilm growth and composition.
Background
Particles and ions of Ti released from dental implants can trigger unfavorable ...biological responses in human cells. However, their effect on oral biofilms composition has not been tested.
Methods
In this blind in situ study, volunteers wore a palatal appliance containing Ti disks for 7 days to allow biofilm formation. Disks were then collected and biofilms were treated, in vitro, with Ti particles (0.75% and 1%), ions (10 and 20 ppm), or a combination of both (1% particles + 20 ppm ions). Biofilms exposed only to medium was used as control group. After 24 hours, biofilms were collected and analyzed by checkerboard DNA‐DNA hybridization. Direct effects of Ti particles and ions on biofilm/cellular morphology were evaluated by transmission electron microscopy (TEM).
Results
Ti particles affected biofilm composition, increasing population of four bacterial species (P < .05), while Ti ions showed higher levels of putative pathogens from the orange complex with reduction in species from the yellow complex (P < .05), compared with control. The combination of particles + ions increased green complex and reduced yellow complex proportions (P < .05). TEM showed clusters of particles agglomerated in extracellular environment, while Ti ions were precipitated in both extracellular and intracellular sites.
Conclusions
Ti products, especially Ti ions, have the potential to change the microbiological composition of biofilms formed on Ti surfaces. Therefore, the presence of Ti products around dental implants may contribute to microbial dysbiosis and peri‐implantitis.
Background
To our knowledge, to date, no studies have comprehensively assessed the changes occurring in the subgingival microbiome of young patients with periodontitis treated by means of mechanical ...and antibiotic therapy. Thus, this study aimed to use next‐generation sequencing to evaluate the subgingival microbial composition of young patients with severe periodontitis treated with scaling and root planing and systemic metronidazole and amoxicillin.
Methods
Subgingival samples from healthy individuals and shallow and deep sites from periodontitis patients were individually collected at baseline and 90 days post‐treatment. The samples were analyzed using 16S rRNA‐gene sequencing (MiSeq‐Illumina) and QIIME pipeline. Differences between groups for the microbiological data were determined using principal coordinate analysis (PCoA), linear mixed models, and the PERMANOVA test.
Results
One hundred samples were collected from 10 periodontitis patients and seven healthy individuals. PCoA analysis revealed significant partitioning between pre‐and post‐treatment samples. No major differences in the composition of the subgingival microbiota were observed between shallow and deep sites, at baseline or at 90‐days post‐treatment, and the microbiome of both site categories after treatment moved closer in similarity to that observed in periodontal health. Treatment significantly improved all clinical parameters and reduced the relative abundance of classical periodontal pathogens and of Fretibacterium fastidiosum, Eubacterium saphenum, Porphyromonas endodontalis, Treponema medium, Synergistetes, TM7, and Treponema spp, and increased that of Actinomyces, Rothia, Haemophilus, Corynebacterium, and Streptococci spp.
Conclusion
Mechanical treatment associated with metronidazole and amoxicillin promoted a beneficial change in the microbiome of young individuals with severe periodontitis.
Aim
To evaluate the clinical effects of different dosages of metronidazole (MTZ) and durations of MTZ + amoxicillin (AMX) in the treatment of generalized chronic periodontitis (GChP).
Material and ...Methods
Subjects with severe GChP were randomly assigned to receive scaling and root planing (SRP)‐only, or combined with 250 or 400 mg of MTZ + AMX (500 mg) thrice a day (TID), for 7 or 14 days. Subjects were monitored for 1 year.
Results
One hundred and nine subjects were enrolled. At 1 year, 61.9% and 63.6% of the subjects receiving AMX + 250 or 400 mg of MTZ for 14 days, respectively, reached the clinical endpoint for treatment (≤4 sites with probing depth ≥5 mm), against 31.8% of those taking 250 or 400 mg of MTZ for 7 days (p < .05) and 13.6% of those receiving SRP‐only (p < .05). Fourteen days of MTZ + AMX was the only significant predictor of subjects reaching the clinical endpoint at 1 year (OR, 5.26; 95% CI, 2.3–12.1, p = .0000). The frequency of adverse events did not differ among treatment groups (p > .05).
Conclusion
The adjunctive use of 400 or 250 mg of MTZ plus 500 mg of AMX/TID/14 days offers statistically significant and clinically relevant benefits over those achieved with SRP alone in the treatment of severe GChP. The added benefits of the 7‐days regimen in this population were less evident. (ClinicalTrials.gov NCT02735395).
Objective
To evaluate the effects of a toothpaste containing 0.3% triclosan in volunteers that have been treated for peri‐implantitis and were enrolled in a maintenance program.
Material and methods
...Subjects presenting at least one implant with peri‐implantitis were selected. They received anti‐infective surgical therapy, and sixty days post‐surgery (baseline) were randomized into two groups, brushing twice/day for 2 years (a) with a toothpaste containing 0.3% triclosan+2.0% PVM/MA copolymer (GantrezTM)+1,450 ppm fluoride (test) or (b) with a toothpaste containing 1,450 ppm fluoride (control). They received clinical and microbiological monitoring at baseline, 3, 6, 12, 18, and 24 months, and professional maintenance every 3 months.
Results
A total of 102 subjects were enrolled (test: 48; control: 54). The control group showed loss of clinical attachment (CA) around treated implants over the course of the study (p < 0.05), while the test group was stable for this parameter. The difference between groups (0.55 mm) for CA change between baseline and 24 months (primary outcome variable) was statistically significant (p < 0.05). Red complex pathogens were only reduced in the test group at 24 months. The implants with no history of peri‐implantitis in the test group had a significant reduction in the percentage of sites with bleeding on probing and in mean probing depth, throughout the study (p < 0.05). This improvement was not observed in the control group.
Conclusion
A toothpaste containing 0.3% triclosan was more effective than a toothpaste without triclosan in maintaining a healthy peri‐implant environment around treated implants and implants with no history of peri‐implantitis during a 2‐year maintenance program (ClinicalTrials.govNCT03191721).
The microbial composition of pericoronitis (Pc) is still controversial; it is not yet clear if the microbial profile of these lesions is similar to the profile observed in periodontitis (Pd). ...Therefore, the aim of the present study was to describe the microbial profile of Pc lesions and compare it directly with that of subjects with Pd.
Subjects with Pc and Pd were selected, and subgingival biofilm samples were collected from (i) third molars with symptomatic Pc (Pc-T), (ii) contralateral third molars without Pc (Pc-C) and (iii) teeth with a probing depth >3 mm from subjects with Pd. Counts and proportions of 40 bacterial species were evaluated using a checkerboard DNA-DNA hybridization technique.
Twenty-six patients with Pc and 18 with Pd were included in the study. In general, higher levels of microorganisms were observed in Pd. Only Actinomyces oris and Eubacterium nodatum were present in higher mean counts in the Pc-T group in comparison with the Pc-C and Pd-C groups (p<0.05). The microbiota associated with Pc-T was similar to that found in Pc-C. Sites with Pc lesions had lower proportions of red complex in comparison with the Pd sites.
The microbiota of Pc is very diverse, but these lesions harbour lower levels of periodontal pathogens than Pd.
Polymicrobial infections are one of the most common reasons for inflammation of surrounding tissues and failure of implanted biomaterials. Because microorganism adhesion is the first step for biofilm ...formation, physical–chemical modifications of biomaterials have been proposed to reduce the initial microbial attachment. Thus, the use of superhydrophobic coatings has emerged because of their anti-biofilm properties. However, these coatings on the titanium (Ti) surface have been developed mainly by dual-step surface modification techniques and have not been tested using polymicrobial biofilms. Therefore, we developed a one-step superhydrophobic coating on the Ti surface by using a low-pressure plasma technology to create a biocompatible coating that reduces polymicrobial biofilm adhesion and formation. The superhydrophobic coating on Ti was created by the glow discharge plasma using Ar, O2, and hexamethyldisiloxane gases, and after full physical, chemical, and biological characterizations, we evaluated its properties regarding oral biofilm inhibition. The newly developed coating presented an increased surface roughness and, consequently, superhydrophobicity (contact angle over 150°) and enhanced corrosion resistance (p < 0.05) of the Ti surface. Furthermore, proteomic analysis showed a unique pattern of protein adsorption on the superhydrophobic coating without drastically changing the biologic processes mediated by proteins. Additionally, superhydrophobic treatment did not present a cytotoxic effect on fibroblasts or reduction of proliferation; however, it significantly reduced (≈8-fold change) polymicrobial adhesion (bacterial and fungal) and biofilm formation in vitro. Interestingly, superhydrophobic coating shifted the microbiological profile of biofilms formed in situ in the oral cavity, reducing by up to ≈7 fold pathogens associated with the peri-implant disease. Thus, this new superhydrophobic coating developed by a one-step glow discharge plasma technique is a promising biocompatible strategy to drastically reduce microbial adhesion and biofilm formation on Ti-based biomedical implants.
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