Non-surgical periodontal therapy with systemic antibiotics in patients with untreated chronic periodontitis: a systematic review and meta-analysis

Grade C Molar-Incisor Pattern Periodontitis in Young Adults: What Have We Learned So Far?

Grade C molar-incisor pattern periodontitis (C-MIP) is a disease that affects specific teeth with an early onset and aggressive progression. It occurs in systemically healthy patients, mostly African descendants, at an early age, with familial involvement, minimal biofilm accumulation, and minor inflammation. Severe and rapidly progressive bone loss is observed around the first molars and incisors. This clinical condition has been usually diagnosed in children and young adults with permanent dentition under 30 years of age. However, this disease can also affect the primary dentition, which is not as frequently discussed in the literature. Radiographic records have shown that most patients diagnosed in the permanent dentition already presented disease signs in the primary dentition. A hyperresponsive immunological profile is observed in local (gingival crevicular fluid-GCF) and systemic environments. Siblings have also displayed a heightened inflammatory profile even without clinical signs of disease. A. actinomycetemcomitans has been classified as a key pathogen in C-MIP in both dentitions. Scaling and root planning associated with systemic antibiotics is the current gold standard to treat C-MIP, leading to GCF biomarker reduction, some systemic inflammatory response modulation and microbiome profile changes to a healthy-site profile. Further studies should focus on other possible disease-contributing risk factors.

Lactobacillus fermentum attenuates the alveolar bone loss in ligature-induced periodontitis in mice

OBJECTIVE

This study investigated the effects of Lactobacillus fermentum BELF11 on periodontitis in mice (LIP).

METHODS

Sixty mice were randomly assigned to a control group (CTL), LIP/PBS group (LIP and PBS applied), or LIP/BELF11 group (LIP and L. fermentum BELF11 applied). For 14 days, PBS or L. fermentum BELF11 was applied twice daily to the mice in the LIP/PBS or LIP/BELF11 group, respectively. After 14 days, radiographic, histological, and pro-inflammatory cytokine assessments were conducted.

RESULTS

The LIP/PBS and LIP/BELF11 groups demonstrated greater alveolar bone loss than the CTL group (p < 0.05). The LIP/BELF11 group showed significantly reduced alveolar bone loss on the mesial side compared to the LIP/PBS group. Histologically, the LIP/BELF11 group showed consistent patterns of connective tissue fiber arrangement, lower levels of inflammatory infiltration, less alveolar bone loss, and higher alveolar bone density than the LIP/PBS group, despite showing more signs of destruction than the CTL group. The LIP/BELF11 group also exhibited significantly lower levels of pro-inflammatory cytokines than the LIP/PBS group.

CONCLUSIONS

L. fermentum BELF11 inhibits alveolar bone loss and periodontitis progression by regulating pro-inflammatory cytokine production. These findings suggest that L. fermentum BELF11 may be a potential adjunctive therapy in periodontal treatment.

Preparation and In Vitro Characterization of Lactococcus lactis-Loaded Alginate Particles as a Promising Delivery Tool for Periodontal Probiotic Therapy

Probiotic microorganisms are used in a variety of food supplements and medical formulations to promote human health. In periodontal therapy, probiotics are mainly used in the form of gels, tablets or rinses that often tend to leak from the periodontal pocket, resulting in a strongly reduced therapeutic effect. In this pilot in vitro study, we present biodegradable alginate-based particles as an alternative, highly efficient system for a periodontal delivery of probiotic bacteria to the inflammation site. For this purpose, Lactococcus (L.) lactis was encapsulated using a standardized pump-controlled extrusion-dripping method. Time-dependent bacterial release in artificial saliva was investigated over 9 days. The effect of freeze drying was explored to ensure long-term storage of L. lactis-loaded particles. Additionally, the particles were bound to dentin surface using approved bioadhesives and subjected to shear stress in a hydrodynamic flow chamber that mimics the oral cavity in vitro. Thus, round particles within the range of 0.80-1.75 mm in radius could be produced, whereby the diameter of the dripping tip had the most significant impact on the size. Although both small and large particles demonstrated a similar release trend of L. lactis, the release rate was significantly higher in the former. Following lyophilization, particles could restore their original shape within 4 h in artificial saliva; thereby, the bacterial viability was not affected. The attachment strength to dentin intensified by an adhesive could resist forces between 10 and 25 N/m2. Full degradation of the particles was observed after 20 days in artificial saliva. Therefore, alginate particles display a valuable probiotic carrier for periodontal applications that have several crucial advantages over existing preparations: a highly stable form, prolonged continuous release of therapeutic bacteria, precise manufacturing according to required dimensions at the application site, strong attachment to the tooth with low risk of dislocation, high biocompatibility and biodegradability.

Comparative Study of Systemic vs. Local Antibiotics with Subgingival Instrumentation in Stage III-IV Periodontitis: A Retrospective Analysis

To improve the clinical and microbiological outcomes of non-surgical mechanical periodontal therapy, the adjunctive use of antimicrobials has been utilized in treating moderate-to-severe periodontitis. In our study, the retrospective design included previously collected health-related patient data, obtained from the printed and digital charts of patients who received systemic or local antibiotic adjuncts to SI (subgingival instrumentation). A total of 34 patients (diagnosed with generalized Stage III/IV periodontitis) met the inclusion and exclusion criteria and were evaluated. The samples were tested for the following bacterial strains: Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), Porphyromonas gingivalis (P. gingivalis), Prevotella intermedia (P. intermedia), Tanererella forsythia (T. forsythia), and Treponema denticola (T. denticola). The inter-group comparisons of the bacterial species did not show statistically significant differences between groups. The present study aimed to evaluate the clinical effects after SI and the adjunctive use of systemically administered (SA) AMX (amoxicillin) + MET (metronidazole) (administered for 7 days), with locally delivered (LDD) piperacillin + tazobactam in step 2 of periodontal therapy. Results: Overall, all parameters were improved in the groups, with a significant difference in inter-group comparison regarding the full-mouth bleeding score (FMBS) (p < 0.05) in favor of the SA group, and the p-value < 0.05 was considered to be statistically significant. Statistically significant PPD (probing pocket depth) reductions and CAL (clinical attachment level) gains were observed in both groups at the 3-month follow-up. In conclusion, within the limitations, the outcomes of this study suggest that SI, with adjunctive local or systemic antibiotic therapy, provided comparable clinical improvements. Systemic AMX + MET protocols were more efficacious with regard to the reduction in FMBS. Follow-up studies with larger patient numbers are needed to further investigate this effect.

Antibiotic resistance in the microbiota of periodontitis patients: an update of current findings

Systemic antibiotics are an effective adjunct in the treatment of periodontitis, but their judicious use is necessary as antimicrobial resistance is a growing global concern. This review aims to explore the current understanding and insight related to antibiotic resistance in the subgingival microbiota of periodontitis patients. A search of MEDLINE (PubMed) was carried out from 1 January 2012 to 25 November 2021 for studies related to antibiotic resistance in periodontitis patients. Of the 90 articles identified, 12 studies were selected for inclusion. A significant incidence of antibiotic resistant isolates was reported for Porphyromonas gingivalis, Prevotella intermedia, Prevotella denticola, Prevotella melaninogenica, Fusobacterium nucleatum, Tanerella forsythia, Aggretibacter actinomycetemcomitans, Streptococcus constellatus, Streptococcus intermedius, and Parvimonas micra, but resistance to specific antibiotics did not reach above 10% of isolates in most studies except for amoxicillin resistance in Aggretibacter actinomycetemcomitans. The highest frequency of resistance across all bacterial species was for amoxicillin, clindamycin, and metronidazole. However, resistance patterns were widely variable across geographical locations, and the high heterogeneity between antibiotic-resistant isolates across studies precludes any clinical recommendations from this study. Although antibiotic resistance has yet to reach critical levels in periodontitis patients, an emphasis on antibiotic stewardship interventions such as point-of-care diagnostics and education for key stakeholders is needed to curb a growing problem.

Exploring the Efficacy of Novel Therapeutic Strategies for Periodontitis: A Literature Review

Periodontitis, a prevalent oral condition, is facing difficulties in therapeutic approaches, sometimes leading to failure. This literature review was conducted to investigate the diversity of other therapeutic approaches and their potential contributions to the successful management of the disease. This research scrutinized the alterations in microbial diversity and imbalances in crucial microbial species, which contribute significantly to the pathogenesis of periodontitis. Within the limitations of this study, we highlight the importance of understanding the treatment plan's role in periodontitis disease, opening the way for further research and innovative treatment plans to mitigate the impact of periodontitis on oral health. This will aid both healthcare professionals and patients in preventing and effectively treating periodontitis, ultimately improving oral health outcomes and overall systemic health and well-being.

Effects of amoxicillin and metronidazole as an adjunct to scaling and root planing on glycemic control in patients with periodontitis and type 2 diabetes: A short-term randomized controlled trial

OBJECTIVE

To assess the effects of amoxicillin and metronidazole with scaling and root planing (SRP) on periodontal parameters and glycemic control in patients with severe periodontitis and diabetes mellitus.

BACKGROUND

Adjunctive antibiotics use is advantageous for treating periodontitis in patients with severe periodontitis and diabetes. However, the effects of adjunctive antibiotic use on hemoglobin A1c (HbA1c) levels remain unclear.

METHODS

This short-term, randomized controlled trial enrolled patients with severe periodontitis and type 2 diabetes. The patients were randomly allocated to SPR only (i.e., control) or SPR + antibiotics (500 mg of amoxicillin and 200 mg of metronidazole, three times daily for 7 days) groups. Periodontal and hematological parameters were assessed at baseline and 3 months after treatment. Inter- and intra-group analyses were performed using Student's t-tests, Mann-Whitney U tests, and the binary logistic regression models. p-values of <.05 were considered statistically significant.

RESULTS

This study enrolled 49 patients, with 23 and 26 patients in the SRP-only and SRP + antibiotics groups, respectively. The periodontal parameters improved significantly and similarly in both groups after treatment (p < .05). The SRP + antibiotics group had more sites of improvement than the SRP-only group when the initial probing depth was >6 mm. (698 [78.96%] vs. 545 [73.35%], p = .008). The HbA1c levels decreased in the SRP-only and SRP + antibiotics groups after treatment (0.39% and 0.53%, respectively). The multivariable binary logistic regression model demonstrated that antibiotics administration and a high baseline HbA1c level were associated with a greater reduction in the HbA1c level (odds ratio = 4.551, 95% confidence interval: 1.012-20.463; odds ratio = 7.162, 95% confidence interval: 1.359-37.753, respectively).

CONCLUSIONS

SRP and SRP plus systemic antibiotics were beneficial for glycemic control. Adjunctive antibiotic use slightly improved the outcome for patients with severe periodontitis and poorly controlled diabetes.

Addressing Antimicrobial Properties in Guided Tissue/Bone Regeneration Membrane: Enhancing Effectiveness in Periodontitis Treatment

Guided tissue regeneration (GTR) and guided bone regeneration (GBR) are the two surgical techniques generally used for periodontitis disease treatment. These techniques are based on a barrier membrane to direct the growth of new bone and gingival tissue at sites with insufficient volumes or dimensions of bone or gingiva for proper function, esthetics, or prosthetic restoration. Numerous studies have highlighted biocompatibility, space-creation, cell-blocking, bioactivity, and proper handling as essential characteristics of a membrane's performance. Given that bacterial infection is the primary cause of periodontitis, we strongly believe that addressing the antimicrobial properties of these membranes is of utmost importance. Indeed, the absence of effective inhibition of periodontal pathogens has been recognized as a primary factor contributing to the failure of GTR/GBR membranes. Therefore, we suggest considering antimicrobial properties as one of the key factors in the design of GTR/GBR membranes. Antibiotics are potent medications frequently administered systemically to combat microbes and mitigate bacterial infections. Nevertheless, the excessive use of antibiotics has resulted in a surge in bacterial resistance. To overcome this challenge, alternative antibacterial substances have been developed. In this review, we explore the utilization of alternative substances with antimicrobial properties for topical application in membranes. The use of antibacterial nanoparticles, phytochemical compounds, and antimicrobial peptides in this context was investigated. By carefully selecting and integrating antimicrobial agents into GTR/GBR membranes, we can significantly enhance their effectiveness in combating periodontitis. These antibacterial substances not only act as barriers against pathogenic bacteria but also promote the process of periodontal healing.

Systemic azithromycin versus amoxicillin/metronidazole as an adjunct in the treatment of periodontitis: a systematic review and meta-analysis

BACKGROUND

The use of systemic azithromycin (AZT) and amoxicillin/metronidazole (AMX/MTZ) as adjuncts provided additional clinical and microbiological benefits over subgingival instrumentation alone. However, the superiority of one antibiotic regimen over another has not been proven. Therefore, the aim of this systematic review and meta-analyses was to evaluate the clinical efficacy and safety of subgingival instrumentation (SI) in conjunction with the systemic use of AZT or AMX/MTZ for the treatment of periodontitis from current published literature.

METHODS

Electronic databases were searched to identify randomized controlled trials (RCTs), controlled clinical trials, prospective and retrospective human studies that compared the adjunctive use of systemic AZT to AMX/MTZ with SI in the treatment of periodontitis. The eligibility criteria were defined based on the participant (who had periodontitis), intervention (SI with adjunctive use of systemic AZT), comparison (SI with adjunctive use of systemic AMX/MTZ), outcomes (primary outcome: changes in probing pocket). The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool. Data were analysed using a statistical software program.

RESULTS

Five studies with 151 participants with periodontitis were included in the present review. Of these, 74 participants received adjunctive AZT, while the remaining participants received AMX/MTZ as an adjunct to SI. The adjunctive use of AZT and AMX/MTZ had comparable changes in probing pocket depths at 1-3 months with no statistically significant difference (mean difference (MD) 0.01; 95% CI -0.20 to 0.22; P = 0.94). The adjunctive use of AZT had significantly fewer number of residual sites with probing pocket depths of ≥5 mm at 1-3 months compared to the adjunctive use of AMX/MTZ (MD -3.41; 95% CI -4.73 to -2.10; P < 0.0001). The prevalence rates of adverse events among participants who received AZT and AMX/MTZ were 9.80% and 14.8%, respectively. The meta-analysis showed that the difference between the two groups was not statistically significant (risk ratio 0.69; 95% CI 0.28 to 1.72; P = 0.43).

CONCLUSIONS

Within the limitation of this review, there was no superiority between AZT and AMX/MTZ in terms of mean changes in probing pocket depths, clinical attachment level, bleeding on probing at 1-3 months. AZT seem to be associated with less sites with residual probing pocket depths of ≥5 mm at 1-3 months and fewer adverse events compared with AMX/MTZ. © 2023 Australian Dental Association.

Systemic antibiotics adjuvants to scaling and root planing in type 2 diabetic and periodontitis individuals: Systematic review with network meta-analysis

Targeting inflammatory pathways is considered a common strategy to control type 2 diabetes (T2D) and periodontitis. This overview was to validate systemic antibiotics as an adjuvant to scaling and root planing (SRP) for the treatments of periodontal patients with T2D. Literature searches were conducted using Web of Science, PubMed, Cochrane, and EMBASE. Randomized trials comparing SRP and systemic antibiotics on glycated hemoglobin (HbA1c) and probing pocket depth (PPD) in adults with T2D and periodontitis were analyzed using network meta-analysis and meta-regression. At 3-month postintervention, meta-analyses of 16 studies revealed that SRP and SRP plus systemic antibiotics (SRPa) had similar significant effects in reducing HbA1c levels of - 0.72% and - 0.96% respectively. While SRP and SRPa also, respectively, reduced PPD of - 0.67 and - 0.89 mm, SRPa showed a better reduction than SRP. At 6-month postintervention, meta-analyses of 7 trials revealed that only SRP was effective in reducing HbA1c levels (-0.29%) but not SRPa. Although both SRP and SRPa still significantly reduced PPD by - 0.56 and - 0.81 mm, respectively, there was no difference between them. The current overview suggested that routine SRP alone is highly recommended for patients with T2D and periodontitis, since systemic antibiotics as an adjuvant provide a rather short-term effect.

Europe's contribution to the evaluation of the use of systemic antimicrobials in the treatment of periodontitis

This narrative review celebrates Europe's contribution to the current knowledge on systemically administered antimicrobials in periodontal treatment. Periodontitis is the most frequent chronic noncommunicable human disease. It is caused by dysbiotic bacterial biofilms and is commonly treated with subgingival instrumentation. However, some sites/patients do not respond adequately, and its limitations and shortcomings have been recognized. This has led to the development of alternative or adjunctive therapies. One is the use of antimicrobials to target bacteria in subgingival biofilms in the periodontal pocket, which can be targeted directly through the pocket entrance with a locally delivered antibiotic or systemically by oral, intravenous, or intramuscular methods. Since the early 20th century, several studies on systemic antibiotics have been undertaken and published, especially between 1990 and 2010. Europe's latest contribution to this topic is the first European Federation of Periodontology, S3-level Clinical Practice Guideline, which incorporates recommendations related to the use of adjuncts to treat stage I-III periodontitis. Understanding the etiopathogenesis of periodontal diseases, specifically periodontitis, has influenced the use of systemic periodontal antibiotic therapy. Randomized clinical trials and systematic reviews with meta-analyses have demonstrated the clinical advantages of adjunctive systemic antimicrobials. However, current recommendations are restrictive due to concerns about antibiotic misuse and the increase in microbial antibiotic resistance. European researchers have contributed to the use of systemic antimicrobials in the treatment of periodontitis through clinical trials and by providing rational guidelines. Nowadays, European researchers are exploring alternatives and directing clinical practice by providing evidence-based guidelines to limit the use of systemic antimicrobials.

Antibacterial Evaluation of Zirconia Coated with Plasma-Based Graphene Oxide with Photothermal Properties

The alternative antibacterial treatment photothermal therapy (PTT) significantly affects oral microbiota inactivation. In this work, graphene with photothermal properties was coated on a zirconia surface using atmospheric pressure plasma, and then the antibacterial properties against oral bacteria were evaluated. For the graphene oxide coating on the zirconia specimens, an atmospheric pressure plasma generator (PGS-300, Expantech, Suwon, Republic of Korea) was used, and an Ar/CH₄ gas mixture was coated on a zirconia specimen at a power of 240 W and a rate of 10 L/min. In the physiological property test, the surface properties were evaluated by measuring the surface shape of the zirconia specimen coated with graphene oxide, as well as the chemical composition and contact angle of the surface. In the biological experiment, the degree of adhesion of Streptococcus mutans (S. mutans) and Porphyromonas gingivalis (P. gingivalis) was determined by crystal violet assay and live/dead staining. All statistical analyzes were performed using SPSS 21.0 (SPSS Inc., Chicago, IL, USA). The group in which the zirconia specimen coated with graphene oxide was irradiated with near-infrared rays demonstrated a significant reduction in the adhesion of S. mutans and P. gingivalis compared with the group not irradiated. The oral microbiota inactivation was reduced by the photothermal effect on the zirconia coated with graphene oxide, exhibiting photothermal properties.

Relationship between Diet Quality and Periodontal Disease in South Korean Adults Aged ≥40 Years

The purpose of this study was to investigate the relationship between diet quality and periodontal disease, in adults aged ≥40 years, using data from the 7th (2016-2018) Korea National Health and Nutrition Survey (KNHANES), representing South Koreans. The subjects of this study were 7935 people aged ≥40 years, who responded to the items in the Korea Healthy Eating Index (KHEI) and underwent periodontal examination. Complex sample univariate and multivariate logistic regression analyses were conducted, to analyze the relationship between the diet quality and periodontal disease. The group with a low diet quality for energy intake balance, showed a higher risk of periodontal disease than the group with a high diet quality for energy intake balance, and it was confirmed that the diet quality in adults aged ≥40 years was related to periodontal disease. Therefore, regular diet evaluations, and the counseling of gingivitis and periodontitis patients by dental experts, will have a positive effect on the restoration and improvement of periodontal health in adults.

Antimicrobial, anti-adhesion, anti-biofilm properties of goji berry (Lycium barbarum) against periodontal bacteria: potential benefits for periodontal diseases

OBJECTIVES

Lycium barbarum, commonly known as goji berry, Himalayan berry, or Tibetian berry, is emerging as a popular "superfood" with anti-inflammatory and antioxidant properties. However, its use for the management of oral inflammatory diseases has not been explored. The present study aims to evaluate the antimicrobial, anti-adhesion, anti-biofilm, and cytotoxic properties of an ethanolic extract of L. barbarum (LBE) against common oral and periodontal pathogens.

METHODS

The antimicrobial properties of LBE against five potential periodontal pathogens (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Prevotella intermedia, Tanerella forsythia) were tested and compared to chlorhexidine and doxycycline using serial dilution and disc diffusion assay. The MTT Assay was performed for evaluating the cytotoxicity and cell viability of the LBE on the gingival fibroblast and modified keratinocyte cell lines. The anti-adhesion and anti-biofilm properties of LBE against P. gingivalis at its minimal bactericidal value were also assessed.

RESULTS

LBE inhibited the growth of periodontal pathogens as compared to control, however, the zone of inhibition of LBE was less when compared to doxycycline and chlorhexidine. The de novo extract showed a maximum zone of inhibition against Tf and Aa. The LBE extract was also compatible to gingival fibroblast tissues and oral keratinocytes at 1 mg/mL.

CONCLUSIONS

L. barbarum is a promising alternative to Chlorhexidine for the management of oral and periodontal infections.

A Local Desiccant Antimicrobial Agent as an Alternative to Adjunctive Antibiotics in the Treatment of Periodontitis: A Narrative Review

Periodontitis is one of the most common oral polymicrobial infectious diseases induced by the complex interplay between the altered subgingival microbiota and the host’s dysregulated immune-inflammatory response, leading to the initiation of progressive and irreversible destruction of the periodontal tissues and eventually to tooth loss. The main goal of cause-related periodontal therapy is to eliminate the dysbiotic subgingival biofilm in order to arrest local inflammation and further periodontal tissue breakdown. Because, in some cases, subgingival mechanical instrumentation has limited efficiency in achieving those goals, various adjunctive therapies, mainly systemic and locally delivered antimicrobials, have been proposed to augment its effectiveness. However, most adjunctive antimicrobials carry side effects; therefore, their administration should be precociously considered. HybenX® (HY) is a commercial therapeutical agent with decontamination properties, which has been studied for its effects in treating various oral pathological conditions, including periodontitis. This review covers the current evidence regarding the treatment outcomes and limitations of conventional periodontal therapies and provides information based on the available experimental and clinical studies related to the HY mechanism of action and effects following its use associated with subgingival instrumentation and other types of dental treatments.

Weak direct current exerts synergistic effect with antibiotics and reduces the antibiotic resistance: An in vitro subgingival plaque biofilm model

BACKGROUND AND OBJECTIVE

Weak direct current (DC) exerts killing effect and synergistic killing effect with antibiotics in some specific bacteria biofilms. However, the potential of weak DC alone or combined with periodontal antibiotics in controlling periodontal pathogens and plaque biofilms remains unclear. The objective of this study was to investigate whether weak DC could exert the anti-biofilm effect or enhance the killing effect of metronidazole (MTZ) and/or amoxicillin-clavulanate potassium (AMC) on subgingival plaque biofilms, by constructing an in vitro subgingival plaque biofilm model.

METHODS

The pooled subgingival plaque and saliva of patients with periodontitis (n = 10) were collected and cultured anaerobically on hydroxyapatite disks in vitro for 48 h to construct the subgingival plaque biofilm model. Then such models were stimulated with 0 μA DC alone (20 min/12 h), 1000 μA DC alone (20 min/12 h), 16 μg/ml MTZ, 16 μg/ml AMC or their combination, respectively. Through viable bacteria counting, metabolic activity assay, quantitative real-time PCR absolute quantification and 16S rDNA sequencing analysis, the anti-biofilm effect of 1000 μA DC and enhanced killing effects of 1000 μA DC combined with antibiotics (MTZ, AMC or MTZ+AMC) were explored.

RESULTS

The old subgingival plaque model (48 h) had no significant difference in total bacterial loads from subgingival plaque in situ, which achieved a similarity of 80%. The 1000 μA DC plus MTZ or AMC for 12 h showed a stronger synergistic killing effect than the same combination for 20 min. The metabolic activity was reduced to the lowest by DC plus MTZ+AMC, as 37.4% of that in the control group, while average synergistic killing effect reached 1.06 log units and average total bacterial loads decreased to 0.87 log units. Furthermore, the relative abundance of the genera Porphyromonas, Prevotella, Treponema_2, and Tannerella were decreased significantly.

CONCLUSION

The presence of weak DC (1000 μA) improved the killing effect of antibiotics on subgingival plaque biofilms, which might provide a novel strategy to reduce their antibiotic resistance.

Relationship between Phenotypic and Genotypic Resistance of Subgingival Biofilm Samples in Patients with Periodontitis

The phenotypic expression of antibiotic resistance genes (ARGs) can hamper the use of antibiotics as adjuncts to subgingival instrumentation in the treatment of periodontitis patients. The aim of the study was to analyze the relationship between the phenotypic and genotypic resistance against ampicillin-sulbactam, clindamycin, doxycycline and metronidazole of subgingival biofilm samples from 19 periodontitis patients. Samples were analyzed with shotgun sequencing and cultivated anaerobically for 7 days on microbiological culture media incorporating antibiotics. All growing isolates were identified to the species level using MALDI-TOF-MS and sequence analysis of the 16S ribosomal RNA (rRNA) gene. Phenotypic resistance was determined using EUCAST-breakpoints. The genetic profile of eight patients matched completely with phenotypical resistance to the tested antibiotics. The positive predictive values varied from 1.00 for clindamycin to 0.57 for doxycycline and 0.25 for ampicillin-sulbactam. No sample contained the nimI gene. It can be concluded that antibiotic resistance may be polygenetic and genes may be silent. Every biofilm sample harboring erm genes was phenotypic resistant. The absence of cfx and tet genes correlated to 100%, respectively, to 75%, with the absence of phenotypic resistance. The absence of nimI genes leads to the assumption that constitutive resistance among several species could explain the resistance to metronidazole.

The Expression of miR-34a in Gingival Crevicular Fluid of Chronic Periodontitis and Its Connection with the TLR/NF-κB Signaling Pathway

Objective

This study analyzed the expression of miR-34a in gingival crevicular fluid (GCF) of patients with chronic periodontitis and its connection with the Toll-like receptor (TLR)/nuclear factor kappa-B (NF-κB) signaling pathway.

Methods

We collected the GCF of the two groups of subjects, using RT-PCR to detect the expression of miR-34a and NF-κB p65 mRNA and TLR4 mRNA and ELISA to detect the inflammatory factor degree in GCF, and performed periodontal examinations on both groups.

Results

The gingival index, bleeding index, probe depth, and attachment loss indexes of periodontal examination in the observation group were remarkably superior to those in the control group (P < 0.05). The levels of IL-1β, IL-6, and TNF-α in the GCF of the observation group were higher than those of the control group (P < 0.05). The mRNA relative expression levels of miR-34a, NF-κB p65, and TLR4 in the GCF of the observation group were dramatically higher than those of the control group (P < 0.05). Correlation analysis showed that miR-34a was highly expressed in patients with chronic periodontitis.

Conclusion

There is an abnormally high expression of miR-34a in GCF of chronic periodontitis. Its expression is associated with the degree of periodontal inflammation, periodontal tissue damage, and the activation of the TLR/NF-κB signaling pathway and could be used as a potential index for auxiliary diagnosis and severity of the disease.

Evaluation of photosensitizer-containing superhydrophobic surfaces for the antibacterial treatment of periodontal biofilms

Antimicrobial photodynamic therapy (aPDT) is a promising approach to control biofilms involved in periodontal diseases. However, certain challenges, such as staining of teeth, preferential interaction of photosensitizer (PS) with Gram-positive versus Gram-negative bacteria, and insufficient oxygen in hypoxic periodontal pockets have presented barriers to its use in the clinic. To overcome these challenges, a novel superhydrophobic (SH) film that generates airborne singlet oxygen has been developed. The SH-aPDT approach isolates the PS onto a topologically rough solid SH film on which channels allow air to diffuse to the PS surface, thus ensuring sufficient oxygen supply. Upon illumination, gas phase singlet oxygen (¹O₂) is produced and diffuses from the SH surface to the underlying biofilm. The killing efficacy was assessed as a function of transmitted fluence (17.9-89.5 J/cm²) and chorin e6 loading (96-1110 nmol/cm²) by counting of colony forming units, biofilm metabolism by XTT and confocal microscopy. The decrease in viability of both Gram-positive and Gram-negative bacteria in a multi-species biofilm was found to be linearly dependent on the fluence as well as the loading of the PS up to 71.6 J/cm² when 1110 nmols/cm² of chlorin e6 was used. A > 4.6 log bacterial reduction was observed under these conditions (p < 0.05). This novel SH-aPDT approach shows promise as an effective method to disinfect multi-species bacterial biofilms associated with periodontal disease and will be evaluated in animal models in future studies.

Photodynamic Therapy for Peri-Implant Diseases

Peri-implant diseases are frequently presented in patients with dental implants. This category of inflammatory infections includes peri-implant mucositis and peri-implantitis that are primarily caused by the oral bacteria that colonize the implant and the supporting soft and hard tissues. Other factors also contribute to the pathogenesis of peri-implant diseases. Based on established microbial etiology, mechanical debridement has been the standard management approach for peri-implant diseases. To enhance the improvement of therapeutic outcomes, adjunctive treatment in the form of antibiotics, probiotics, lasers, etc. have been reported in the literature. Recently, the use of photodynamic therapy (PDT)/antimicrobial photodynamic therapy (aPDT) centered on the premise that a photoactive substance offers benefits in the resolution of peri-implant diseases has gained attention. Herein, the reported role of PDT in peri-implant diseases, as well as existing observations and opinions regarding PDT, are discussed.

Clinical, microbiological and immunological effects of 3- or 7-day systemic antibiotics adjunctive to subgingival instrumentation in patients with aggressive (stage III/IV grade C) periodontitis: a randomized placebo-controlled clinical trial

AIM

To evaluate the clinical non-inferiority of a 3-day-protocol of systemic antibiotics adjunctive to subgingival instrumentation (SI) compared to a 7-day-protocol in patients with stage III/IV grade C periodontitis.

METHODS

50 systemically healthy patients (32.7±4.3 years) with aggressive periodontitis (stage III/IV grade C periodontitis) were treated by SI and adjunctive amoxicillin and metronidazole randomly assigned to group A: (n=25) 500mg antibiotics 3-times-daily for 3 days, followed by placebo 3-times-daily for 4 days, or group B: (n=25) 500mg AB 3-times-daily for 7 days. Clinical, microbial and immunological parameters were assessed at baseline, 3 and 6 months, and patient-related outcomes after 2 weeks. The primary outcome variable was the number of residual sites with PD≥6mm at 6 months.

RESULTS

For the primary outcome variable (the number of residual sites with PD≥6mm at 6 months), the null hypothesis was rejected and demonstrated the non-inferiority of the 3d AB protocol compared to 7d AB (the upper limits of the 95%CI for ITT: [-2.572; 1.050] and PP: [-2.523; 1.318] were lower than the assumed margin of Δ=3.1). Comparable clinical improvements were obtained for all parameters with both antibiotic protocols (p>0.05). All investigated periodontopathogens and pro-inflammatory host-derived markers were statistically significantly reduced, without differences between the treatments (p>0.05).

CONCLUSION

These findings indicate that in patients with aggressive periodontitis (stage III/IV grade C periodontitis), a 3-day systemic administration of amoxicillin and metronidazole adjunctive to SI may lead to non-inferior clinical outcomes after 6-months with fewer adverse events compared to a 7-day-protocol.

Antimicrobial and cytotoxicity properties of Plumeria alba flower extract against oral and periodontal pathogens: A comparative in vitro study

Context:

Plumeria alba, commonly known as frangipani or West Indian jasmine, is a traditional and ancient folklore medicine known for its antimicrobial, anti-inflammatory, and antioxidant properties. The extracts from P. alba obtained from the leaves, bark, and flowers, are commonly used to manage bacterial, fungal, and viral infections such as herpes, scabies, and fungal infections. The constituents of the P. alba plant have shown promising antihelmintic, antipyretic, and antirheumatic properties. Although studies have confirmed that extracts from Plumeria species are effective against microbial infections and cancer, its role in managing oral diseases, particularly the chronic inflammatory disease of the gums (gingivitis and periodontitis), has never been explored. Therefore, the current study aimed to explore the antimicrobial and cytotoxic properties of the P. alba flower extract against oral and periodontal pathogens compared to chlorhexidine and doxycycline.

Settings and Design:

This was an in vitro study.

Materials and Methods:

The ethanolic extract was prepared from the freshly plucked P. alba flowers. The antimicrobial properties of the extract were evaluated by testing the minimal inhibitory concentration, minimal bactericidal concentration, and well-diffusion assay against Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Prevotella intermedia, Tannerella forsythia, Streptococcus mutans, Actinomyces viscosus, Streptococcus salivarius, and Candida albicans. The results were compared to chlorhexidine and doxycycline. The cytotoxicity was checked by the against human-derived gingival fibroblast and keratinocytes.

Statistical Analysis Used:

One-way ANOVA for the mean zones of inhibition against all the microorganisms was done.

Results:

P. alba extract inhibited the growth for all the tested oral and periodontal pathogens at 25 μg/ml. The well-diffusion assay of P. alba extract was comparable to chlorhexidine but was not statistically significant compared to doxycycline.

Conclusion:

P. alba can be used as a promising alternative to chlorhexidine for the management of oral and periodontal infections.

Changes in salivary matrix metalloproteinase-3, -8, and -9 concentrations after 6 weeks of non-surgical periodontal therapy

Background

Studies using salivary inflammatory biomarkers for diagnosing and monitoring the progression of periodontal disease have garnered increased attention in recent years. The present study aimed to identify changes in clinical parameters and concentrations of salivary matrix metalloproteinases (MMPs) following 6 weeks of non-surgical periodontal therapy (NSPT).

Methods

A 6-week NSPT program was applied to 51 adults aged ≥ 20 years. The program involved scaling, root planing, and professional toothbrushing for healthy participants and those with periodontal disease. Patients with periodontal disease underwent professional toothbrushing during all three visits. Periodontal pocket depth (PD) and gingival bleeding were assessed at week 0, week 3, and week 6, and saliva samples were collected to measure the concentrations of MMP-3, -8, and -9.

Results

All clinical parameters were improved in the periodontal disease groups following the NSPT course. Compared with healthy participants, the patients with periodontal disease showed increased concentrations of salivary MMP-3, -8, and -9. During the 6-week program, patients with periodontal disease also showed significant reductions in PD and gingival bleeding during the third week; no significant reduction was found during the sixth week. Significant reductions in the concentrations of salivary MMP-3, -8, and -9 were also noted in the periodontal disease group at week 3. The sensitivity and specificity of MMP-3 for predicting periodontitis were 81.8% and 55.5%, respectively.

Conclusion

The present study found that NSPT resulted in reductions of salivary MMP-3, -8, and -9, and identified the potential of MMP-3 as a biomarker in the diagnosis of periodontal disease. These findings may serve as foundational data for future studies into the development of diagnostic kits for periodontal disease.

Effect of systemic antibiotic and probiotic therapies as adjuvant treatments of subgingival instrumentation for periodontitis: a randomized controlled clinical study

Objective:

This study assessed the efficacy of two adjunct therapies (antibiotic and probiotic) for periodontal treatment based on clinical and immunological parameters in patients with Stage II and III Grade B periodontitis.

Methodology:

45 patients were randomly allocated into three groups: control group (CG); antibiotic group (GAtb), in which 500 mg amoxicillin + 400 mg metronidazole were used; and probiotic group (GProb), for which Lactobacillus reuteri was used. Patients received medications after undergoing periodontal debridement. Clinical and immunological parameters were assessed at baseline, 30 days, and 90 days.

Results:

All therapies reduced bleeding on probing (BoP) in the evaluated periods, and the GAtb had a greater reduction at 90 days (p=0.03). The GProb group showed better results for plaque index (PI) and gingival recession (GR) compared to the GAtb at 90 days (p=0.0014; p=0.006). The area of inflammation (PISA Index) significantly decreased in all therapies in the evaluated periods. Therapies had no significant differences regarding moderate pockets. The GAtb had a greater reduction in probing depth (PD) for deep pockets (p=0.03) at 90 days and in the number of deep pocket sites at 30 days (p=0.04). The occurrence of adverse effects was commonly reported in the GAtb as a percentage per patient. The GAtb had a significant reduction in the concentration of interleukins IL-1β and IL-8 and an increase in IL-10 and TNF-α. The CG had a reduction in IL-6 and IL-1 β, whereas in the GProb there was no difference.

Conclusion:

After three months, none of the adjuvant therapies provided any additional benefit for subgingival instrumentation.

A novel removable appliance for canine retraction: a case report

This case report outlines the use of a modified Leighton's retractor as a method for canine retraction in a patient with severe hypodontia, a history of aggressive periodontitis with tooth loss and idiopathic root resorption affecting multiple teeth. Treatment involved an upper removable appliance in combination with a lower sectional fixed appliance with the aim of improving aesthetics and function for the patient, whilst balancing the need to minimise treatment duration and modify treatment mechanics to reduce the orthodontic risks.

Diagnosis and Management of Furcation Lesions in Dogs - A Review

The furcation is the anatomic area where the roots divide on a multirooted tooth. Periodontal disease causing alveolar bone loss can lead to furcation lesions of various stages. Once furcation involvement has occurred, the area can be more difficult to clean or treat due to the complex anatomy and morphology of furcations. Teeth with short root trunks, longer tooth roots, and roots with wide furcation entrance areas/degrees of separation and wide root divergence are considered better candidates for long term maintenance. Dog teeth possess many of these advantageous anatomic features compared to human teeth. Treatment options for teeth with furcation lesions include: closed debridement, open debridement, furcation plasty, tunneling, partial tooth or root resection, root separation (hemisection or trisection), regenerative therapies, or exodontia. There are many factors to consider in determining treatment options. The favorable and unfavorable characteristics for maintenance of teeth with furcation lesions are summarized. Home care and ongoing professional care are important aspects of periodontal disease control for any patient. Studies of systemic and local antibiotic therapies in human patients have not demonstrated reduction of furcation stages, and probiotic effects at furcation sites have not been specifically examined. Human review studies show that most molar teeth once deemed "hopeless" due to stage 3 furcation lesions can be maintained for at least 5 to 15 years with supportive periodontal therapy. Similar long term studies in dogs are needed to improve the evidence-based management of canine patients with furcation lesions.

Azithromycin as an adjunct to subgingival professional mechanical plaque removal in the treatment of grade C periodontitis: a systematic review and meta-analysis

The aim of this systematic review was to evaluate clinical and microbiological outcomes with the use of azithromycin as an adjunct to non-surgical subgingival professional mechanical plaque removal (PMPR) in the treatment of grade C periodontitis. Online database searches using high-level MeSH terms in a PICO structure were conducted along with hand-searching of relevant periodontal journals. Titles and abstracts of identified studies were independently reviewed by both authors and the full texts of studies meeting the inclusion criteria were independently reviewed. In total, 122 studies were identified through searches, of which 6 were included in the qualitative analysis and 4 in the meta-analysis. Three studies included in the meta-analysis were deemed at low risk of bias and 1 at serious risk. There were conflicting results on whether azithromycin reduced the number of subgingival pathogens or detectable subgingival Aggregatibacter actinomycetemcomitans between the included studies. The meta-analysis revealed a statistically significant probing depth reduction difference in favour of azithromycin compared to the control at 3 months (weighted mean difference [WMD]=−0.39 mm; 95% confidence interval [CI], −0.66 to −0.13 mm; I²=0%) and 12 months (WMD=−1.32 mm; 95% CI, −1.71 to −0.93 mm; I²=0%). The clinical attachment level change was also statistically significant in favour of azithromycin compared to the control at 3 months (WMD=−0.61 mm; 95% CI, −1.13 to −0.10 mm; I²=71%) and 12 months (WMD=−0.88 mm; 95% CI, −1.32 to −0.44 mm; I²=0%). Based upon these results, azithromycin offers additional improvements in some clinical parameters when used in conjunction with subgingival PMPR in patients with aggressive periodontitis over control groups. These improvements appear to be maintained for up to 12 months after treatment completion. However, due to a lack of well-designed studies, the conclusions that can be drawn from the available evidence are limited.

Clinical and microbiological effects of photodynamic therapy applied in non-surgical treatment of periodontitis

Background/Aim. Treatment of periodontitis undergoes several treatment phases. Non-surgical periodontal treatment (NSPT) represents the basic treatment stage, and it is applied to all the patients undergoing periodontal treatment. Adjunctive antimicrobial photodynamic therapy (aPDT) is one of several contemporary and relatively new possibilities with a role to inactivate microorganisms responsible for the occurrence and progression of the disease. The aim of this study was to comparatively analyze the clinical and microbiological effects of the NSPT alone, as well as combined with aPDT. Methods. A split-mouth method design was used in a prospective randomized controlled trial. The following clinical parameters were registered and monitored: plaque index (PI), bleeding on probing, probing depth (PD), and clinical attachment level (CAL). The presence of microorganisms Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Treponema denticola was detected by the polymerase chain reaction (PCR) method. Samples were tested before the therapy, as well as three months after the therapy. Therapeutic modalities of NSPT and NSPT with adjunct aPDT were examined. Results. All of the analyzed clinical parameters proved statistically significant improvement after the application of both treatment modalities (p < 0.001). Microbiological analyses showed that the total number of microorganisms was statistically significantly lower after the application of both methods (p < 0.001). Following the treatment, there was a statistically significantly reduced number of microorganisms Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Treponema denticola (p < 0.001). NSPT combined with aPDT led to a statistically significant improvement of both clinical parameters and microbiological status compared to NSPT applied on its own. Conclusion. The study showed improvement of all clinical indicators after the application of both treatment modalities. The total number of microorganisms was reduced as well as the number of specific microorganisms. Combining aPDT with NSPT led to a statistically significantly higher reduction in the number of microorganisms compared to NSPT alone.

Evaluation of systemic antibiotic usage in the treatment of periodontal diseases among dental professionals in Turkey: Cross - sectional epidemiological study

Background/Aim: Systemic antibiotic use in periodontal diseases has increased in recent years. The purpose of this study was to investigate the antibiotic prescribing patterns for systemic antibiotics for the treatment of periodontal diseases. Material and Methods: A prepared questionnaire was sent to the e-mail addresses of dentists located in seven different regions of Turkey, who were requested to reply the questions online. In total, 512 emails were sent for the study, which was carried out with the participation of general dentists (GDs), periodontists (PDs), and specialist dentists (SDs). The participants were asked questions about their professional experiences, the institutions that they work for, and their antibiotic training and knowledge, their perspectives on clinical antibiotic use and antibiotic preferences invarious clinical situations. Results: 65.5% of GDs, 23.3% of PDs, 11.6% of SDs participated in this study. In reviewing the participants' systemic antibiotic use to treat periodontal diseases, most preferred systemic antibiotics to treat acute necrotizan ulcerative gingivitis, aggressive periodontitis, diabetes associated periodontitis. Regarding antibiotic prescriptions, 40.7% of the GDs and 34.8% of the SDs prescribed 1-3 antibiotics per day. Meanwhile, 31.3% of the PDs prescribed 1-3 antibiotics a day and 31.3% 1-4 antibiotics a week (p<0.005). Conclusions: Based on the results of this survey, shows that dentists do not have sufficient training for systemic antibiotic use and that their current approach is based on clinical experience alone. Clearer, more specific guidelines and increased post-graduate education can lead to a reduction in the negative consequences of this issue's resultant over-prescribed antibiotics.

Classic vs. Novel Antibacterial Approaches for Eradicating Dental Biofilm as Adjunct to Periodontal Debridement: An Evidence-Based Overview

Periodontitis is a multifactorial chronic inflammatory disease that affects tooth-supporting soft/hard tissues of the dentition. The dental plaque biofilm is considered as a primary etiological factor in susceptible patients; however, other factors contribute to progression, such as diabetes and smoking. Current management utilizes mechanical biofilm removal as the gold standard of treatment. Antibacterial agents might be indicated in certain conditions as an adjunct to this mechanical approach. However, in view of the growing concern about bacterial resistance, alternative approaches have been investigated. Currently, a range of antimicrobial agents and protocols have been used in clinical management, but these remain largely non-validated. This review aimed to evaluate the efficacy of adjunctive antibiotic use in periodontal management and to compare them to recently suggested alternatives. Evidence from in vitro, observational and clinical trial studies suggests efficacy in the use of adjunctive antimicrobials in patients with grade C periodontitis of young age or where the associated risk factors are inconsistent with the amount of bone loss present. Meanwhile, alternative approaches such as photodynamic therapy, bacteriophage therapy and probiotics showed limited supportive evidence, and more studies are warranted to validate their efficiency.

Effect of Azithromycin on Mineralized Nodule Formation in MC3T3-E1 Cells

Azithromycin displays immunomodulatory and anti-inflammatory effects in addition to broad-spectrum antimicrobial activity and is used to treat inflammatory diseases, including respiratory and odontogenic infections. Few studies have reported the effect of azithromycin therapy on bone remodeling processes. The aim of this study was to examine the effects of azithromycin on the osteogenic function of osteoblasts using osteoblast-like MC3T3-E1 cells. Cells were cultured in the presence of 0, 0.1, 1, and 10 µg/mL azithromycin, and cell proliferation and alkaline phosphatase (ALPase) activity were determined. In vitro mineralized nodule formation was detected with alizarin red staining. The expression of collagenous and non-collagenous bone matrix protein was determined using real-time PCR or enzyme-linked immunosorbent assays. In cells cultured with 10 µg/mL azithromycin, the ALPase activity and mineralized nodule formation decreased, while the type I collagen, bone sialoprotein, osteocalcin, and osteopontin mRNA expression as well as osteopontin and phosphorylated osteopontin levels increased. These results suggest that a high azithromycin concentration (10 µg/mL) suppresses mineralized nodule formation by decreasing ALPase activity and increasing osteopontin production, whereas low concentrations (≤l.0 µg/mL) have no effect on osteogenic function in osteoblastic MC3T3-E1 cells.

Clindamycin as an Alternative Option in Optimizing Periodontal Therapy

Periodontal disease is an oral infectious and inflammatory disease caused by microorganisms that determine the host-mediated destruction of soft and hard periodontal tissues, which ultimately leads to tooth loss. Periodontitis affects a large part of the population, with various degrees of severity. Treatment consists of etiologic therapy: the removal of biofilm through mechanical debridement plus microbial elimination by supplementary measures. Antibiotic administration, either systemically or through local delivery, has been shown to improve clinical outcomes after mechanical periodontal treatment. Clindamycin is a lincosamide with a broad spectrum, being active against aerobic, anaerobic, and β-lactamase-producing bacteria. This antibiotic offers several advantages and some disadvantages and has been used in periodontal treatment both systemically and locally with various degrees of success. Among the properties that recommend it for periodontal treatment is the bacteriostatic effect, the inhibition of bacterial proteins synthesis, the enhancement of neutrophil chemotaxis, phagocytosis and the oxidative burst–oxidative stress storm. Furthermore, it is easily absorbed at the level of oral tissues in a considerable amount. This substantial tissue penetration, especially inside the bone, is synergistic with a stimulating effect on the host immune system. The aim of this review is to explore the applicability of this antibiotic agent and to evaluate its antimicrobial potential and limitations at the level of the oral biofilm associated with periodontal disease.

Anti-inflammatory activity of psoralen in human periodontal ligament cells via estrogen receptor signaling pathway

Psoralen is one of the most effective ingredients extracted from the Chinese herb, Psoralea corylifolia L. Studies have found that psoralen has anti-inflammatory and estrogen-like effects; however, little research has been conducted to elucidate the mechanisms underlying these effects. Through the molecule docking assay, psoralen was found to have a better combination with ERα than ERβ. In human periodontal ligament cells, psoralen was found to upregulate the estrogen target genes (e.g., CTSD, PGR, TFF1) and down-regulate the expression of inflammatory cytokines (TNF-α, IL-1β, IL-6 and IL-8) stimulated by P. gingivalis LPS, as well as TLR4-IRAK4-NF-κb signaling pathway proteins. These effects were reversed by the ER antagonist ICI 182780. These results indicated that psoralen may exert anti-inflammatory effects as an agonist to ER, which could provide a theoretical basis for the use of psoralen for adjuvant therapy and prevention of periodontitis.

Clinical, microbiological, and immunological effects of systemic probiotics in periodontal treatment: study protocol for a randomized controlled trial

BACKGROUND

The association of scaling and root planing (SRP) with systemic metronidazole (MTZ) plus amoxicillin (AMX) has shown to be an effective treatment protocol, particularly for periodontitis stages III and IV, generalized. More recently, probiotics have also been suggested as a promising adjunctive treatment for periodontal diseases due to their antimicrobial and anti-inflammatory properties. Therefore, the aim of this randomized clinical trial (RCT) is to evaluate the clinical, microbiological, and immunological effects of probiotics as adjuncts to SRP alone or with MTZ+AMX in the treatment of periodontitis.

METHODS

Subjects with periodontitis are being randomly assigned to receive (i) SRP alone, or with (ii) two probiotic lozenges/day for 90 days (Prob), (iii) MTZ (400 mg) and AMX (500 mg) thrice a day (TID) for 14 days (MTZ+AMX), or (iv) Prob and MTZ+AMX. Subjects are being monitored for up to 12 months post-treatment. Nine subgingival plaque samples per patient are being collected at baseline and at 3, 6, and 12 months post-therapy and analyzed by checkerboard DNA-DNA hybridization for 40 bacterial species. Peripheral blood and gingival crevicular fluid (GCF) of four randomly selected periodontal sites will be analyzed by means of a multiplex fluorescent bead-based immunoassay for 17 cyto/chemokines.

STATISTICAL ANALYSES

The significance of differences in each group (over the course of the study) will be sought using repeated measures ANOVA or Friedman tests and among groups (at each time point) using either ANOVA/ANCOVA or Kruskal-Wallis tests, depending on normality of the data. The chi-square test will be used to compare differences in the frequency of subjects achieving the clinical endpoint for treatment (≤ 4 sites with PD ≥ 5 mm) at 1 year and of self-perceived adverse effects. A stepwise forward logistic regression analysis will be performed in order to investigate the impact of different predictor variables on the percentage of patients achieving the clinical endpoint for treatment. The Number Needed to Treat (NNT) with different treatment protocols will be also calculated. Statistical significance will be set at 5%.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03733379. Registered on November 7, 2018.

Characterization of an ester-based core-multishell (CMS) nanocarrier for the topical application at the oral mucosa

OBJECTIVES

Topical drug administration is commonly applied to control oral inflammation. However, it requires sufficient drug adherence and a high degree of bioavailability. Here, we tested the hypothesis whether an ester-based core-multishell (CMS) nanocarrier is a suitable nontoxic drug-delivery system that penetrates efficiently to oral mucosal tissues, and thereby, increase the bioavailability of topically applied drugs.

MATERIAL AND METHODS

To evaluate adhesion and penetration, the fluorescence-labeled CMS 10-E-15-350 nanocarrier was applied to ex vivo porcine masticatory and lining mucosa in a Franz cell diffusion assay and to an in vitro 3D model. In gingival epithelial cells, potential cytotoxicity and proliferative effects of the nanocarrier were determined by MTT and sulphorhodamine B assays, respectively. Transepithelial electrical resistance (TEER) was measured in presence and absence of CMS 10-E-15-350 using an Endohm-12 chamber and a volt-ohm-meter. Cellular nanocarrier uptake was analyzed by laser scanning microscopy. Inflammatory responses were determined by monitoring pro-inflammatory cytokines using real-time PCR and ELISA.

RESULTS

CMS nanocarrier adhered to mucosal tissues within 5 min in an in vitro model and in ex vivo porcine tissues. The CMS nanocarrier exhibited no cytotoxic effects and induced no inflammatory responses. Furthermore, the physical barrier expressed by the TEER remained unaffected by the nanocarrier.

CONCLUSIONS

CMS 10-E-15-350 adhered to the oral mucosa and adhesion increased over time which is a prerequisite for an efficient drug release. Since TEER is unaffected, CMS nanocarrier may enter the oral mucosa transcellularly.

CLINICAL RELEVANCE

Nanocarrier technology is a novel and innovative approach for efficient topical drug delivery at the oral mucosa.

Systemic azithromycin as an adjunct to scaling and root planing in patients with stage III/IV periodontitis: 12-month results of a randomized controlled clinical trial

OBJECTIVES

To determine whether azithromycin (AZI) as an adjunct to scaling and root planing (SRP), when compared to placebo, decreases the number of sites demonstrating pocket depth (PD) ≥ 5 mm and bleeding on probing (BOP) 12 months post-treatment in stage III/IV periodontitis patients.

MATERIALS AND METHODS

In a double-blind randomized parallel-arm placebo-controlled trial, 40 stage III/IV periodontitis patients received steps 1 and 2 of periodontal treatment in two sessions within 7 days. Patients then received systemic antibiotic therapy (n = 20; AZI 500 mg/day, 3 days) or placebo (n = 20). Additional instrumentation of residual diseased sites (DS) - sites with PD ≥ 5 mm and BOP - was performed at the 3-, 6- and 9-month follow-ups. The primary outcome variable was the number of DS at the 12-month re-evaluation. Using a multivariate multilevel logistic regression model, the effects of gender, age, antibiotic therapy, presence of Porphyromonas gingivalis or Aggregatibacter actinomycetemcomitans, smoking, tooth being a molar and interdental location were evaluated.

RESULTS

The number of DS after 12 months was similar in the test (median (Me) = 4, interquartile range (IQR) = 0-6) and control (Me = 3, IQR = 1-6.5) groups. Both groups showed substantial but equivalent improvements in periodontal parameters, with no intergroup differences at initially shallow or deep sites. The logistic regression showed a lower odds ratio (OR) for the healing of DS on molars (OR = 0.29; p < 0.001) and in smokers (OR = 0.36; p = 0.048).

CONCLUSION

Stage III/IV periodontitis patients showed significant but comparable improvements in periodontal parameters and the number of residual DS at the 12-month revaluation regardless of treatment type. This may have been the result of the additional instrumentation received by patients at residual DS in both treatment groups.

CLINICAL RELEVANCE

Treatment with AZI + SRP provided no additional benefits after 12 months in terms of periodontal parameters or the number of persisting sites with PD ≥ 5 mm + BOP as compared to SRP plus placebo.

TRIAL REGISTRATION

EUDRA-CT: 2015-004306-42; https://www.clinicaltrialsregister.eu/ctr-search/trial/2015-004306-42/SI , registered 17. 12. 2015.

Antimicrobial photodynamic therapy versus antibiotics as an adjunct in the treatment of periodontitis and peri-implantitis: A systematic review and meta-analysis

BACKGROUND

Clinical efficacy of antimicrobial photodynamic therapy (aPDT) as compared to antibiotics in periodontitis and peri-implantitis has been tested in several clinical trials. Yet controversial results were reported. The aim of the present study was to answer the question: "Will adjunctive antimicrobial photodynamic therapy be more effective than antibiotics agent in the treatment of periodontitis and peri-implantitis?".

METHODS

Publications compared outcomes between aPDT and antibiotics in adult patients with periodontitis or peri-implantitis, containing more than 3-month follow-up duration, were involved in the systematic review and meta-analysis. PubMed, EMBASE and Cochrane Central were searched until December of 2020. Clinical parameters including pocket probing depth (PPD), clinical attachment level (CAL), and bleeding on probing (BOP) were evaluated. The risk of bias was assessed by Cochrane Collaboration Tool. Weighted mean differences (WMD), 95 % confidence interval(CI) and heterogeneity were estimated by Review Manager software.

RESULTS

10 trials in periodontitis and 5 trials in peri-implantitis were included. Meta-analysis outcomes revealed equal clinical evidence for aPDT and antibiotics in periodontitis and peri-implantitis. In addition, aPDT significantly reduced the red complex in both diseases. However, owing to the heterogeneity of protocols in articles and the limited number of studies, the comparative conclusion remained unconfirmed.

CONCLUSION

aPDT can be considered as an alternative to antibiotics in the treatment of peri-implantitis and periodontitis. Given that high heterogeneity in outcome was found in this review, future long-term clinical trials with standard aPDT and antibiotic treatment should be tested to arrive at a firm conclusion.

Treatment of localized aggressive periodontitis alters local host immunoinflammatory profiles: A long-term evaluation

AIM

To evaluate the local immunoinflammatory profiles in localized aggressive periodontitis patients (LAP) before and after periodontal treatment and maintenance.

METHODS

Sixty-six African-Americans with LAP (7-21 years old) were included. After periodontal examination, all patients received periodontal treatment with mechanical debridement plus systemic amoxicillin/metronidazole for 7 days. Gingival crevicular fluid was collected from diseased and healthy sites at baseline and 3, 6, 12, and 24 months following treatment. Levels of 16 inflammatory/bone resorption markers were determined using Milliplex^® . Univariate and correlation analyses were performed among all parameters/biomarkers. Discriminant analyses (DA) evaluated profile differences between LAP diseased and healthy sites at each time point as compared to the baseline.

RESULTS

Reductions in the clinical parameters (except for visible plaque) were observed at all time points compared to the baseline. Levels of IL-12p70, IL-2, IL-6, MIP-1α, RANKL, and OPG were reduced after treatment, and several cytokines/chemokines were correlated with clinical parameters reductions. DA showed that differences in the immunoinflammatory profiles between LAP diseased and healthy sites decreased after periodontal treatment compared to the baseline.

CONCLUSIONS

Periodontal treatment modified the local immunoinflammatory profile of LAP sites in the long term, as suggested by changes in biomarkers from baseline, along with clinical stability of the disease. (Clinicaltrials.gov number, NCT01330719).

Adjunctive systemic antimicrobials in the treatment of chronic periodontitis: A systematic review and network meta-analysis

The aim of this systematic review and network meta-analysis was to assess the efficacy of antimicrobials adjunctive to scaling and root planing (SRP) in the treatment of chronic periodontitis. The study was conducted according to the PRISMA statement. The protocol (CRD42020178621) was registered on the International Prospective Register of Systematic Reviews (PROSPERO). The MEDLINE, EMBASE, and CENTRAL databases were searched up to March 2020; furthermore, a manual search of relevant periodontal journals was conducted. Mean differences (MD) and standard deviations were calculated for clinical attachment level (CAL) gain and probing depth (PD) reduction at 6 and 12 months. A network meta-analysis was performed to assess direct and indirect comparisons and to establish a ranking of treatments. A total of 21 randomized clinical trials (RCTs) were included in the systematic review. Network meta-analysis showed that SRP + amoxicillin (AMX) + metronidazole (MTZ), as compared to SRP, reached the highest PD reduction at 6 [MD = 0.47; 95% CI (0.3; 0.64)] and 12 months [MD = 0.51; 95% CI (0.25; 0.78)], and CAL gain at 6 [MD = 0.54; 95% CI (0.27; 0.8)] and 12 months [MD = 0.37; 95% CI (0.05; 0.69)]. Network meta-analysis indicated that AMX + MTZ adjunctive to SRP provided the best improvement in clinical parameters, followed by SRP + MTZ.

Utility of procalcitonin as an early diagnostic marker of bacteremia in individuals with periodontitis Stage II and III

BACKGROUND

The aim of the present study is to assess the ability of procalcitonin (PCT) to differentiate between periodontal health and Stage II and III periodontitis. We further assessed, if PCT can reflect early bacteremia induced by non-surgical periodontal treatment (NSPT).

METHODS

Sixty-four systemically healthy individuals were divided into Group I, periodontally healthy, and Group II, Stage II and III periodontitis. NSPT was done for both the groups. Standardized serum and salivary samples were obtained and analyzed for PCT levels using highly sensitive double antibody sandwich enzyme-linked immunosorbent assay at baseline and 2 weeks. In addition, the serum levels of PCT were recorded at immediate and 1-hour post-NSPT.

RESULTS

Mean PCT levels (saliva = 0.03 ng/mL and serum = 0.05 ng/mL) in periodontally healthy group were considerably lower than that in the periodontitis group (saliva = 0.22 ng/mL and serum = 1.85 ng/mL) with significant intergroup comparison at P < 0.001. Post NSPT the mean serum PCT values increased from 1.854 ng/mL to 1.871 ng/mL at the immediate interval and remained at 0.879 ng/mL after 2 weeks at P < 0.001. Spearman correlation showed highly significant positive correlation between serum and salivary PCT values to clinical attachment level (CAL) at P < 0.001 and rho = 0.78 and 0.75, respectively. Linear regression model showed serum PCT to be a significant predictor for CAL.

CONCLUSION

Screening for serum PCT levels in patients with periodontitis could act not only as a guide to assess the bacterial load and use of antibiotics but also as a predictor for CAL loss in patients with periodontitis.

Adjunctive systemic antimicrobials for the non-surgical treatment of periodontitis

BACKGROUND

Systemic antimicrobials can be used as an adjunct to mechanical debridement (scaling and root planing (SRP)) as a non-surgical treatment approach to manage periodontitis. A range of antibiotics with different dosage and combinations are documented in the literature. The review follows the previous classification of periodontitis as all included studies used this classification.

OBJECTIVES

To assess the effects of systemic antimicrobials as an adjunct to SRP for the non-surgical treatment of patients with periodontitis.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases to 9 March 2020: Cochrane Oral Health's Trials Register, CENTRAL, MEDLINE, and Embase. The US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) which involved individuals with clinically diagnosed untreated periodontitis. Trials compared SRP with systemic antibiotics versus SRP alone/placebo, or with other systemic antibiotics.

DATA COLLECTION AND ANALYSIS

We selected trials, extracted data, and assessed risk of bias in duplicate. We estimated mean differences (MDs) for continuous data, with 95% confidence intervals (CIs). We assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included 45 trials conducted worldwide involving 2664 adult participants. 14 studies were at low, 8 at high, and the remaining 23 at unclear overall risk of bias. Seven trials did not contribute data to the analysis. We assessed the certainty of the evidence for the 10 comparisons which reported long-term follow-up (≥ 1 year). None of the studies reported data on antimicrobial resistance and patient-reported quality of life changes. Amoxicillin + metronidazole + SRP versus SRP in chronic/aggressive periodontitis: the evidence for percentage of closed pockets (MD -16.20%, 95% CI -25.87 to -6.53; 1 study, 44 participants); clinical attachment level (CAL) (MD -0.47 mm, 95% CI -0.90 to -0.05; 2 studies, 389 participants); probing pocket depth (PD) (MD -0.30 mm, 95% CI -0.42 to -0.18; 2 studies, 389 participants); and percentage of bleeding on probing (BOP) (MD -8.06%, 95% CI -14.26 to -1.85; 2 studies, 389 participants) was of very low certainty. Only the results for closed pockets and BOP showed a minimally important clinical difference (MICD) favouring amoxicillin + metronidazole + SRP. Metronidazole + SRP versus SRP in chronic/aggressive periodontitis: the evidence for percentage of closed pockets (MD -12.20%, 95% CI -29.23 to 4.83; 1 study, 22 participants); CAL (MD -1.12 mm, 95% CI -2.24 to 0; 3 studies, 71 participants); PD (MD -1.11 mm, 95% CI -2.84 to 0.61; 2 studies, 47 participants); and percentage of BOP (MD -6.90%, 95% CI -22.10 to 8.30; 1 study, 22 participants) was of very low certainty. Only the results for CAL and PD showed an MICD favouring the MTZ + SRP group. Azithromycin + SRP versus SRP for chronic/aggressive periodontitis: we found no evidence of a difference in percentage of closed pockets (MD 2.50%, 95% CI -10.19 to 15.19; 1 study, 40 participants); CAL (MD -0.59 mm, 95% CI -1.27 to 0.08; 2 studies, 110 participants); PD (MD -0.77 mm, 95% CI -2.33 to 0.79; 2 studies, 110 participants); and percentage of BOP (MD -1.28%, 95% CI -4.32 to 1.76; 2 studies, 110 participants) (very low-certainty evidence for all outcomes). Amoxicillin + clavulanate + SRP versus SRP for chronic periodontitis: the evidence from 1 study, 21 participants for CAL (MD 0.10 mm, 95% CI -0.51 to 0.71); PD (MD 0.10 mm, 95% CI -0.17 to 0.37); and BOP (MD 0%, 95% CI -0.09 to 0.09) was of very low certainty and did not show a difference between the groups. Doxycycline + SRP versus SRP in aggressive periodontitis: the evidence from 1 study, 22 participants for CAL (MD -0.80 mm, 95% CI -1.49 to -0.11); and PD (MD -1.00 mm, 95% CI -1.78 to -0.22) was of very low certainty, with the doxycycline + SRP group showing an MICD in PD only. Tetracycline + SRP versus SRP for aggressive periodontitis: we found very low-certainty evidence of a difference in long-term improvement in CAL for the tetracycline group (MD -2.30 mm, 95% CI -2.50 to -2.10; 1 study, 26 participants). Clindamycin + SRP versus SRP in aggressive periodontitis: we found very low-certainty evidence from 1 study, 21 participants of a difference in long-term improvement in CAL (MD -1.70 mm, 95% CI -2.40 to -1.00); and PD (MD -1.80 mm, 95% CI -2.47 to -1.13) favouring clindamycin + SRP. Doxycycline + SRP versus metronidazole + SRP for aggressive periodontitis: there was very low-certainty evidence from 1 study, 27 participants of a difference in long-term CAL (MD 1.10 mm, 95% CI 0.36 to 1.84); and PD (MD 1.00 mm, 95% CI 0.30 to 1.70) favouring metronidazole + SRP. Clindamycin + SRP versus metronidazole + SRP for aggressive periodontitis: the evidence from 1 study, 26 participants for CAL (MD 0.20 mm, 95% CI -0.55 to 0.95); and PD (MD 0.20 mm, 95% CI -0.38 to 0.78) was of very low certainty and did not show a difference between the groups. Clindamycin + SRP versus doxycycline + SRP for aggressive periodontitis: the evidence from 1 study, 23 participants for CAL (MD -0.90 mm, 95% CI -1.62 to -0.18); and PD (MD -0.80 mm, 95% CI -1.58 to -0.02) was of very low certainty and did not show a difference between the groups. Most trials testing amoxicillin, metronidazole, and azithromycin reported adverse events such as nausea, vomiting, diarrhoea, mild gastrointestinal disturbances, and metallic taste. No serious adverse events were reported.

AUTHORS' CONCLUSIONS

There is very low-certainty evidence (for long-term follow-up) to inform clinicians and patients if adjunctive systemic antimicrobials are of any help for the non-surgical treatment of periodontitis. There is insufficient evidence to decide whether some antibiotics are better than others when used alongside SRP. None of the trials reported serious adverse events but patients should be made aware of the common adverse events related to these drugs. Well-planned RCTs need to be conducted clearly defining the minimally important clinical difference for the outcomes closed pockets, CAL, PD, and BOP.

Microbiological and host-derived biomarker evaluation following non-surgical periodontal therapy with short-term administration of systemic antimicrobials: secondary outcomes of an RCT

Nonsurgical periodontal therapy with adjunctive use of systemic antimicrobials (for 7-14 days) showed improved clinical, microbiological and immunological results over the mechanical protocol alone. Considering the increasing risk for antimicrobial resistance with longer antibiotic regimes, it is important to establish the optimal antibiotic protocol with a maximum antimicrobial benefit and minimum risk for adverse effects. The aim of the study was to evaluate the microbiological and inflammatory outcomes 12-months after a 3-/7-day systemic antibiotic protocol [amoxicillin (AMX) + metronidazole (MET)] adjunctive to subgingival debridement in severe periodontitis compared to mechanical treatment alone. From the initially treated 102 patients, 75 subjects (Placebo group: n = 26; 3-day AMX + MET group: n = 24; 7-day AMX + MET group: n = 25) completed the 12-month examination. Clinical parameters, eight periodontal pathogens and inflammatory markers were determined at baseline and 3-, 6-, 12-months after therapy using real-time PCR and ELISA respectively. After 6 months, several periodontopathogens were significantly more reduced in the two antibiotic groups compared to placebo (p < 0.05). After 1 year, both antibiotic protocols showed significant reductions and detection of the keystone pathogen P. gingivalis compared to placebo. Antibiotic protocols, smoking, disease severity, baseline-BOP, -CAL and -IL-1β, as well as detection of T. denticola at 12-months significantly influenced the residual number of deep sites. The present data indicate that the systemic use of both short and longer antibiotic protocols (AMX + MET) adjunctive to nonsurgical periodontal therapy lead to higher microbiological improvements compared to subgingival debridement alone. The two investigated antibiotic protocols led to comparable microbiological and inflammatory results.

A systematic review on bacterial community changes after periodontal therapy with and without systemic antibiotics: An analysis with a wider lens

BACKGROUND

This systematic review aimed to provide a comprehensive view on microbial community shifts after periodontal therapy with and without systemic antibiotics, conducted in randomized controlled trials (RCTs).

METHODS

Search functions in PubMed, Scopus, the Web of Knowledge, and the Cochrane Oral Health Library databases were used to locate studies published up to December 2018 that reported at least two bacteria before and after periodontal therapy. Gray literature and manual searching were done. Information about reported bacteria in those studies were extracted, and a descriptive microbial community analysis was conducted to observe trends and influencing factors on microbial dynamics. Methodological aspects were examined, including the bacterial detection method, heterogeneity of procedures, and risk of bias (RoB) of the studies.

RESULTS

The 30 included studies reported 130 different bacterial genera. Four different detection methods were reported: cultivation, polymerase chain reaction, DNA-DNA-checkerboard hybridization, and 16S rDNA amplicon sequencing. No general compositional change between the antibiotic and placebo groups could be found after therapy on the community level. Fifty-five bacteria were reported in two or more studies. Of those, 24 genera decreased and 13 increased more frequently after antibiotic use. Great heterogeneity between procedures and variability in RoB were found among the studies.

CONCLUSIONS

Microbial shifts occurred regardless of the use of antibiotics. Antibiotic therapy seems to induce more changes in single bacteria. The heterogeneity in methods and reporting of the included studies preclude clinical recommendations on the use or not of adjunctive antibiotics. The present results may guide further research on the topic.

The Use of Antimicrobial Photodynamic Therapy to Maintain a Hopeless Tooth With a PeriodonticEndodontic Lesion: A Case Report

Background: In spite of some advances in periodontal generative methods, it is impossible to stop progressive Loss of supporting alveolar bone in some end-stage periodontitis. The aim of this study is to report a kind of treatment modality which was seemed to be successes full in maintaining teeth. In this case-report, a hopeless tooth was saved by combined non-surgical periodontalendodontal treatment and antimicrobial photodynamic therapy (aPDT). Case Report: A 58-year-old male presented with a chief complaint of pain and mobility of tooth number 38. Clinical examinations revealed a periodontic-endodontic lesion with clinical attachment loss exceeding 10 mm and grade III mobility. To preserve the tooth, we operated nonsurgical periodontal treatment including scaling and root planning (SRP) plus root canal therapy (RCT) combined with intra-root canal non-aPDT laser decontamination. Then we applied laser pocket therapy with and without aPDT. Following 6 months of the aPDT treatment, the mobility and pocket depth of the tooth improved from grade III to I and from 10 to 3 millimeters respectively. Conclusion: aPDT is a novel adjunctive therapy that can be used for various conditions with microbial etiology. This case report demonstrated that aPDT might be effective in the treatment of periodontic-endodontic lesions in a hopeless tooth.

Mechanical Debridement with Antibiotics in the Treatment of Chronic Periodontitis: Effect on Systemic Biomarkers-A Systematic Review

In this systematic review, we assessed the effectiveness of systemic antibiotics as an adjunctive therapy to mechanical debridement in improving inflammatory systemic biomarkers, as compared to mechanical debridement alone, among adults with chronic periodontitis. We searched relevant electronic databases for eligible randomized controlled trials. Two review authors independently screened, extracted data, and assessed risk of bias. We conducted meta-analysis, assessed heterogeneity, and assessed certainty of evidence using GRADEPro software. We included 19 studies (n = 1350 participants), representing 18 randomized controlled trials and found very little or no impact of antibiotics on inflammatory biomarkers. A meta-analysis of eight studies demonstrated a mean reduction of 0.26 mm in the periodontal pockets at three months (mean difference [MD] −0.26, 95%CI: −0.36 to −0.17, n = 372 participants, moderate certainty of evidence) in favor of the antibiotics. However, results from five studies reporting clinical attachment level (mm) yielded little or no difference at three months (MD −0.16, 95% CI: −0.35 to 0.03, n = 217 participants) between antibiotic and placebo groups. There is little or no evidence that adjunctive systemic antibiotics therapy improves inflammatory systemic biomarkers, compared to mechanical debridement alone, among adults with chronic periodontitis.

Hybrid Hydrogels for Synergistic Periodontal Antibacterial Treatment with Sustained Drug Release and NIR-Responsive Photothermal Effect

BACKGROUND

Periodontal pathogenic bacteria promote the destruction of periodontal tissues and cause loosening and loss of teeth in adults. However, complete removal of periodontal pathogenic bacteria, at both the bottom of the periodontal pocket and the root bifurcation area, remains challenging. In this work, we explored a synergistic antibiotic and photothermal treatment, which is considered an alternative strategy for highly efficient periodontal antibacterial therapy.

METHODS

Mesoporous silica (MSNs) on the surface of Au nanobipyramids (Au NBPs) were designed to achieve the sustained release of the drug and photothermal antibacterials. The mesoporous silica-coated Au NBPs (Au NBPs@SiO2) were mixed with gelatin methacrylate (GelMA-Au NBPs@SiO2). Au NBPs@SiO2 and GelMA-Au NBPs@SiO2 hybrid hydrogels were characterized, and the drug content and photothermal properties in terms of the release profile, bacterial inhibition, and cell growth were investigated.

RESULTS

The GelMA-Au NBPs@SiO2 hybrid hydrogels showed controllable minocycline delivery, and the drug release rates increased under 808 nm near-infrared (NIR) light irradiation. The hydrogels also exhibited excellent antibacterial properties, and the antibacterial efficacy of the antibiotic and photothermal treatment was as high as 90% and 66.7% against Porphyromonas gingivalis (P. gingivalis), respectively. Moreover, regardless of NIR irradiation, cell viability was over 80% and the concentration of Au NBPs@SiO2 in the hybrid hydrogels was as high as 100 µg/mL.

CONCLUSION

We designed a new near-infrared light (NIR)-activated hybrid hydrogel that offers both sustained release of antibacterial drugs and photothermal treatment. Such sustained release pattern yields the potential to rapidly eliminate periodontal pathogens in the periodontal pocket, and the photothermal treatment maintains low bacterial retention after the drug treatment.

Periodontal disease and adverse pregnancy outcomes

Periodontal diseases are considered not only to affect tooth-supporting tissues but also to have a cause-and-effect relationship with various systemic diseases and conditions, such as adverse pregnancy outcomes. Mechanistic studies provide strong evidence that periodontal pathogens can translocate from infected periodontium to the feto-placental unit and initiate a metastatic infection. However, the extent and mechanisms by which metastatic inflammation and injury contribute to adverse pregnancy outcomes still remain unclear. The presence of oral bacteria in the placenta of women with term gestation further complicates our understanding of the biology behind the role of periodontal pathogens in pregnancy outcomes. Epidemiological studies demonstrate many methodological inconsistencies and flaws that render comparisons difficult and conclusions insecure. Therefore, despite the fact that a number of prospective studies show a positive association between periodontal diseases and various adverse pregnancy outcomes, the evidence behind it is still weak. Future well-designed explanatory studies are necessary to verify this relationship and, if present, determine its magnitude. The majority of high-quality randomized controlled trials reveal that nonsurgical periodontal therapy during the second trimester of gestation does not improve pregnancy outcomes. From a biological standpoint, this can be partially explained by the fact that therapy rendered at the fourth to sixth months of pregnancy is too late to prevent placental colonization by periodontal pathogens and consequently incapable of affecting pathogen-induced injury at the feto-placental unit. Thus, interventions during the preconception period may be more meaningful. With the increase in our understanding on the potential association between periodontal disease and adverse pregnancy outcomes, it is clear that dental practitioners should provide periodontal treatment to pregnant women that is safe for both the mother and the unborn child. Although there is not enough evidence that the anti-infective therapy alters pregnancy outcomes, it improves health-promoting behavior and periodontal condition, which in turn advance general health and risk factor control.