Antibiotic Resistance in Patients with Peri-Implantitis: A Systematic Scoping Review

Current research progress on Prevotella intermedia and associated diseases

Prevotella intermedia is a Gram-negative anaerobic bacterium that is a common pathogen of periodontitis. Recent studies have revealed that P. intermedia is closely associated with a variety of diseases involving multiple systems. Under the action of its virulence factors such as cysteine protease and adhesins, P. intermedia has the ability to bind and invade various host cells including gingival fibroblasts. It can also copolymerize a variety of pathogenic bacteria, leading to interference with the host's immune inflammatory response and causing various diseases. In this article, we review the progress of research on P. intermedia virulence factors and bacterial pathogenesis, and the correlation between P. intermedia and various diseases.

Systemic antibiotics in the surgical treatment of peri-implantitis: A randomized placebo-controlled trial

AIM

To study the clinical, radiographic and microbiological outcomes after surgical treatment of peri-implantitis, with or without adjunctive systemic antibiotics.

MATERIALS AND METHODS

Eighty-four patients (113 implants) with peri-implantitis were randomized into three groups (A, amoxicillin and metronidazole; B, phenoxymethylpenicillin and metronidazole; or C, placebo). Treatment included resective surgery and implant surface decontamination with adjunctive antibiotics or placebo. Primary outcomes were probing pocket depth (PPD) reduction and marginal bone level (MBL) stability. Secondary outcomes were treatment success (defined as PPD ≤ 5 mm, bleeding on probing [BOP] ≤ 1site, absence of suppuration on probing [SOP] and absence of progressive bone loss of >0.5 mm), changes in BOP/SOP, mucosal recession (REC), clinical attachment level (CAL), bacterial levels and adverse events. Outcomes were evaluated for up to 12 months. The impact of potential prognostic indicators on treatment success was evaluated using multilevel logistic regression analysis.

RESULTS

A total of 76 patients (104 implants) completed the study. All groups showed clinical and radiological improvements over time. Statistically significant differences were observed between groups for MBL stability (A = 97%, B = 89%, C = 76%), treatment success (A = 68%, B = 66%, C = 28%) and bacterial levels of Aggregatibacter actinomycetemcomitans and Tannerella forsythia, favouring antibiotics compared to placebo. Multiple regression identified antibiotic use as potential prognostic indicator for treatment success. Gastrointestinal disorders were the most reported adverse events in the antibiotic groups.

CONCLUSIONS

Adjunctive systemic antibiotics resulted in additional improvements in MBL stability. However, the potential clinical benefits of antibiotics need to be carefully balanced against the risk of adverse events and possible antibiotic resistance.

Machine learning enabled design features of antimicrobial peptides selectively targeting peri-implant disease progression

Peri-implantitis is a complex infectious disease that manifests as progressive loss of alveolar bone around the dental implants and hyper-inflammation associated with microbial dysbiosis. Using antibiotics in treating peri-implantitis is controversial because of antibiotic resistance threats, the non-selective suppression of pathogens and commensals within the microbial community, and potentially serious systemic sequelae. Therefore, conventional treatment for peri-implantitis comprises mechanical debridement by nonsurgical or surgical approaches with adjunct local microbicidal agents. Consequently, current treatment options may not prevent relapses, as the pathogens either remain unaffected or quickly re-emerge after treatment. Successful mitigation of disease progression in peri-implantitis requires a specific mode of treatment capable of targeting keystone pathogens and restoring bacterial community balance toward commensal species. Antimicrobial peptides (AMPs) hold promise as alternative therapeutics through their bacterial specificity and targeted inhibitory activity. However, peptide sequence space exhibits complex relationships such as sparse vector encoding of sequences, including combinatorial and discrete functions describing peptide antimicrobial activity. In this paper, we generated a transparent Machine Learning (ML) model that identifies sequence-function relationships based on rough set theory using simple summaries of the hydropathic features of AMPs. Comparing the hydropathic features of peptides according to their differential activity for different classes of bacteria empowered predictability of antimicrobial targeting. Enriching the sequence diversity by a genetic algorithm, we generated numerous candidate AMPs designed for selectively targeting pathogens and predicted their activity using classifying rough sets. Empirical growth inhibition data is iteratively fed back into our ML training to generate new peptides, resulting in increasingly more rigorous rules for which peptides match targeted inhibition levels for specific bacterial strains. The subsequent top scoring candidates were empirically tested for their inhibition against keystone and accessory peri-implantitis pathogens as well as an oral commensal bacterium. A novel peptide, VL-13, was confirmed to be selectively active against a keystone pathogen. Considering the continually increasing number of oral implants placed each year and the complexity of the disease progression, prevalence of peri-implant diseases continues to rise. Our approach offers transparent ML-enabled paths towards developing antimicrobial peptide-based therapies targeting the changes in the microbial communities that can beneficially impact disease progression.

Lung Abscess Caused by Tannerella forsythia Infection: A Case Report

Background

Tannerella forsythia is a gram-negative anaerobic bacterium commonly found in the oral cavity. It is among the common pathogenic bacteria associated with gingivitis, chronic periodontitis, and aggressive periodontitis. However, there is currently no literature discussing lung abscesses primarily caused by T. forsythia infection.

Presentation

This article presents the case of a 55-year-old male with a massive lung abscess. The patient underwent ultrasound-guided percutaneous drainage, and the sample was sent for pathogen metagenomic next-generation sequencing (mNGS) testing. The test indicated that the lung abscess was primarily caused by T. forsythia infection. A literature review was conducted to understand the characteristics of this pathogen as well as its clinical features and suitable treatment approaches.

Conclusion

Currently, there is no literature specifically mentioning T. forsythia as a primary pathogen causing lung abscesses. This anaerobic bacterium is commonly found in the oral cavity and is difficult to cultivate using routine culture methods. mNGS emerges as a value diagnostic method for identifying this pathogen. Treatment recommendations include drainage and antibiotic selection encompassing common periodontal pathogens such as red complex bacteria and Actinomyces.

Vacuum Ultraviolet (VUV) Light Photofunctionalization to Induce Human Oral Fibroblast Transmigration on Zirconia

Soft tissue adhesion and sealing around dental and maxillofacial implants, related prosthetic components, and crowns are a clinical imperative to prevent adverse outcomes of periodontitis and periimplantitis. Zirconia is often used to fabricate implant components and crowns. Here, we hypothesized that UV treatment of zirconia would induce unique behaviors in fibroblasts that favor the establishment of a soft tissue seal. Human oral fibroblasts were cultured on zirconia specimens to confluency before placing a second zirconia specimen (either untreated or treated with one minute of 172 nm vacuum UV (VUV) light) next to the first specimen separated by a gap of 150 µm. After seven days of culture, fibroblasts only transmigrated onto VUV-treated zirconia, forming a 2.36 mm volume zone and 5.30 mm leading edge. Cells migrating on VUV-treated zirconia were enlarged, with robust formation of multidirectional cytoplastic projections, even on day seven. Fibroblasts were also cultured on horizontally placed and 45° and 60° tilted zirconia specimens, with the latter configurations compromising initial attachment and proliferation. However, VUV treatment of zirconia mitigated the negative impact of tilting, with higher tilt angles increasing the difference in cellular behavior between control and VUV-treated specimens. Fibroblast size, perimeter, and diameter on day seven were greater than on day one exclusively on VUV-treated zirconia. VUV treatment reduced surface elemental carbon and induced superhydrophilicity, confirming the removal of the hydrocarbon pellicle. Similar effects of VUV treatment were observed on glazed zirconia specimens with silica surfaces. One-minute VUV photofunctionalization of zirconia and silica therefore promotes human oral fibroblast attachment and proliferation, especially under challenging culture conditions, and induces specimen-to-specimen transmigration and sustainable photofunctionalization for at least seven days.

Progress in Nanostructured Mechano-Bactericidal Polymeric Surfaces for Biomedical Applications

Bacterial infections and antibiotic resistance remain significant contributors to morbidity and mortality worldwide. Despite recent advances in biomedical research, a substantial number of medical devices and implants continue to be plagued by bacterial colonisation, resulting in severe consequences, including fatalities. The development of nanostructured surfaces with mechano-bactericidal properties has emerged as a promising solution to this problem. These surfaces employ a mechanical rupturing mechanism to lyse bacterial cells, effectively halting subsequent biofilm formation on various materials and, ultimately, thwarting bacterial infections. This review delves into the prevailing research progress within the realm of nanostructured mechano-bactericidal polymeric surfaces. It also investigates the diverse fabrication methods for developing nanostructured polymeric surfaces with mechano-bactericidal properties. We then discuss the significant challenges associated with each approach and identify research gaps that warrant exploration in future studies, emphasizing the potential for polymeric implants to leverage their distinct physical, chemical, and mechanical properties over traditional materials like metals.

A Systematic Review and Meta-Analysis of Systemic and Local Antibiotic Therapy in the Surgical Treatment of Peri-Implantitis

(1) Background: Given the existing controversy regarding the use of antibiotics in the treatment of peri-implantitis, this systematic review and meta-analysis aim to ascertain how beneficial the role of systemic and local antibiotics is in peri-implant surgical therapy, considering the harmful effects that they represent and the abuse of antibiotics in terms of global health. (2) Methods: To determine the therapeutic efficacy of the administration of antibiotics in the surgical treatment of peri-implantitis in terms of probing pocket depth (PPD) and bleeding on probing (BoP), electronic and manual bibliographic searches were carried out in the Embase and PubMed databases, collecting data that related to before and after treatment. (3) Results: The adjunctive use of local antibiotics provides significant improvements in PPD (MD = 1.29; 95% CI: 0.56 to 2.02; p ≤ 0.0006; I² = 0%) when compared with surgical treatment alone. No significant differences were found in the other subgroup; that is, the use of systemic antibiotics did not significantly improve PPD changes in the surgical treatment of peri-implantitis (MD = 0.40; 95% CI: -0.15 to 0.95; p = 0.15; I² = 0). (4) Conclusions: The use of local antibiotics in the surgical treatment of peri-implantitis seems to offer treatment improvements in terms of PPD and BoP, unlike that observed with the use of systemic antibiotics. However, these results should be taken with caution as they also depend on the type of surgical technique used, whether regenerative or resective. More research is needed on this topic to understand the role of local and systemic antibiotics in the treatment of peri-implantitis.

A Systematic Review of Randomized Clinical Trials Evaluating the Efficacy of Minimally Invasive Surgery for Soft Tissue Management: Aesthetics, Postoperative Morbidity, and Clinical Results

Background and Objectives: The necessity for less invasive and patient-friendly surgical therapies guided the development of the "minimally invasive surgical technique" (MIST). The aim of this systematic review was to evaluate the efficacy of MIST for soft tissue management considering aesthetic results, postoperative morbidity, and clinical outcomes. Materials and Methods: Several databases were used to conduct a thorough analysis of the scientific evidence. To investigate randomized clinical trials (RCTs), MeSH terms and keywords were provided. Results: Eleven RCTs were chosen. These experiments included 273 patients. The trials that explored MIST for papilla preservation presented greater efficacy in increasing papillary height (p < 0.05). MIST showed stable clinical outcomes for the management of excessive gingival display and with a flapless technique for single implant placement. Considering the treatment of gingival recessions, some RCTs presented greater root coverage with MIST (p < 0.05), while other trials did not show differences between groups. Regarding aesthetic perception, five RCTs indicated high patient satisfaction with MIST (p < 0.05). Similarly, six RCTs reported that patients in the MIST group presented significantly less post-surgical pain and lower wound healing scores (p < 0.01). Conclusions: It was concluded that using MIST resulted in more clinical studies reporting better clinical outcomes. Considering aesthetic appearance, slightly more than half of the clinical trials also showed improved results with MIST. Likewise, regarding postoperative morbidity, 60% of the clinical trials also described better scores with MIST. All of this indicates that MIST is a good alternative for the management of soft tissues.

Efficacy of Periodontal Endoscopy during Subgingival Debridement to Treat Periodontitis: A Systematic Review of Randomized Clinical Trials

This study aims to evaluate the clinical efficacy of periodontal endoscopy (PEND) during subgingival debridement to treat periodontitis. A systematic review of randomized clinical trials (RCTs) was performed. The search strategy included four databases: PubMed, Web of Sciences, Scopus, and Scielo. The initial online exploration generated 228 reports, and 3 RCTs met the selection criteria. These RCTs described a statistically significant decrease in probing depth (PD) in the PEND group compared to controls after 6 and 12 months of follow-up. The improvement in PD was 2.5 mm for PEND and 1.8 mm for the control groups, respectively (p < 0.05). It was also described that the PEND group presented a significantly inferior proportion of PD 7 to 9 mm at 12 months (0.5%) as compared to the control group (1.84%) (p = 0.03). All RCTs noted improvements in clinical attachment level (CAL). It was described as having significant differences in bleeding on probing (BOP) in favor of PEND, with an average reduction of 43% versus 21% in the control groups. Similarly, it was also presented that they were significant differences in plaque indices in favor of PEND. PEND during subgingival debridement to treat periodontitis demonstrated efficacy in reducing PD. Improvement was also observed in CAL and BOP.

Growth Conditions Influence Lactobacillus Cell-Free Supernatant Impact on Viability, Biofilm Formation, and Co-Aggregation of the Oral Periodontopathogens Fusobacterium nucleatum and Porphyromonas gingivalis

Fusobacterium nucleatum and Porphyromonas gingivalis human periodontopathogens play a leading part in oral squamous cell carcinoma through cell proliferation, invasion, and persistent inflammation promotion and maintenance. To explore how the activity of Lactobacillus-derived cell-free supernatants (CFSs) can be influenced by growth medium components, CFSs were produced both in the standard MRS and the novel animal-derivative-free “Terreno Industriale Lattobacilli” (TIL) media, and in vitro screened for the containment of F. nucleatum and P. gingivalis both single and co-cultured and also for the interference on their co-aggregation. The viability assay demonstrated that the Limosilactobacillus reuteri LRE11 and Ligilactobacillus salivarius LS03 MRS-produced CFSs were significantly more effective against single and co-cultured pathogens. All the other CFSs significantly improved their efficacy when produced in TIL. Both MRS- and TIL-produced CFSs significantly inhibited the single and co-cultured pathogen biofilm formation. Only Levilactobacillus brevis LBR01 CFS in MRS specifically reduced F. nucleatum and P. gingivalis co-aggregation, while viable LBR01, LS03, and LRE11 in MRS significantly co-aggregated with the pathogens, but only LS03 cultivated in TIL improved this effect. This work paves the way to better consider environmental growth conditions when screening for probiotic and postbiotic efficacy as crucial to pathogen aggregation, adhesion to the host’s niches, and exclusion.