Antibiotics/antimicrobials: systemic and local administration in the therapy of mild to moderately advanced periodontitis

Encapsulated Chlorhexidine Gel Use in Adolescents Undergoing Orthodontic Treatment: A Randomised Trial

INTRODUCTION

The majority of orthodontic patients present with plaquebiofilm and related manifestations in the early stages of active fixed orthodontic appliance use.

AIMS

To evaluate the effects of a slow-delivery chlorhexidine:beta-cyclodextrin (Cx:β-Cd) gel compared with those of free Cx free formulations on clinical parameters in patients undergoing treatment with fixed orthodontic appliances.

METHODS

Patients aged 12-18 years received prophylaxis and scaling and were randomised to treatment groups in a double-blinded manner. They were treated with Cx:β-Cd, Cx, or placebo gel for 15 or 30 days. Bleeding on probing and the visible plaque index were recorded, and gingival crevicular fluid samples were collected for the assessment of cytokine expression.

RESULTS

At 15 days, the Cx:β-Cd group exhibited significantly less BOP than did the Cx and control groups (P < 0.001; n = 116). At 15 days, notable decreases in tumour necrosis factor-α and interferon-γ expression, as well as a substantial increase in interleukin-10 expression, were observed in the Cx:β-Cd and Cx groups relative to the control group (P < 0.05). The molecular encapsulation gel resulted in greater saliva Cx concentrations than did the free Cx gel released concentrations of 800 ng g-1.

CONCLUSION

Cx:β-Cd gel is effective for the slow delivery of Cx, improving the gingival health of adolescents undergoing orthodontic treatment.

CLINICAL RELEVANCE

A single application of encapsulated Cx gel, was a more effective antiseptic than a free Cx application in fixed orthodontice appliance wearers.

Effects of Local and Systemic Metronidazole as Adjunctive Treatment in Chronic Periodontitis Patients

OBJECTIVES

This study aimed to compare the effects of local and systemic metronidazole in patients with chronic periodontitis.

MATERIALS AND METHODS

In this randomized clinical study, 30 patients (3 teeth per patient) were treated in three groups: scaling and root planing (SRP) treatment alone, metronidazole tablet as adjunctive treatment, and metronidazole gel as adjunctive treatment. BOP (bleeding on probing), PPD (pocket probing depth), and CAL (clinical attachment level) data were collected at the beginning and 3 months later. Collected data were tested by Wilcoxon and Kruskal-Wallis tests.

RESULTS

BOP, CAL, and PPD levels were significantly different at the beginning of treatment and after 3 months, and this was true for all treatments. BOP, CAL, and PPD levels did not differ significantly between the three groups after the treatment (p > 0.05).

CONCLUSION

The effectiveness of these methods was all equal and SRP is still considered as the gold standard in the treatment of periodontal diseases. Further studies are needed to confirm the findings. Chronic periodontitis is a progressive disease that can cause tooth loss. The accepted treatment is SRP. Antibiotics used systemically can penetrate the depth of the periodontal pockets but have several side effects. Hence, using a less complicated medicinal form as a topical gel as adjunctive therapy in treating chronic periodontitis can be more effective.

TRIAL REGISTRATION

Iranian clinical trial https://en.irct.ir/: IRCT20210408050898N1.

Alveolar Ridge Regeneration With Open Versus Closed Healing in Damaged Extraction Sockets: A Preclinical In Vivo Study

OBJECTIVE

The objective of this study was to compare open versus closed healing of soft and hard tissue following alveolar ridge preservation (ARP) procedures in damaged extraction sockets.

MATERIALS AND METHODS

ARP was performed in five mongrel dogs using collagenated deproteinized bovine bone mineral (cDBBM) and a resorbable non-cross-linked collagen membrane (NCCM) in damaged extraction sockets, with each socket entrance left either open (open group) or closed (closed group). Clinical wound epithelization at the socket entrance and the dimensions of keratinized tissue were evaluated over time. Additionally, the augmented ridge dimensions and new bone formation were assessed radiographically and histologically at 8 weeks after surgery.

RESULTS

The dimensions of the socket entrance gradually decreased in the open group, and wound epithelization was almost complete within 4 weeks. The mucogingival junction was maintained more apically in the open group than in the closed group (0.14 ± 0.40 mm vs. -0.86 ± 0.71 mm [mean ± SD], p < 0.05). The augmented ridge dimensions did not differ significantly between the open and closed groups (93.1% ± 5.4% vs. 88.3% ± 11.2%, p > 0.05). Histological analyses revealed no significant differences in the amount of newly formed bone. However, membrane resorption in the crestal region was more pronounced in the open group.

CONCLUSION

Open and closed healing approaches for ARP in extraction sockets with damaged buccal wall resulted in similar ridge dimensions and new bone formation. However, there was less reduction of the buccal bone crest and wider keratinized tissue width after open healing.

Multifunctional human serum albumin-crosslinked and self-assembling nanoparticles for therapy of periodontitis by anti-oxidation, anti-inflammation and osteogenesis

Periodontitis is a chronic inflammatory disease that can result in the irreversible loss of tooth-supporting tissues and elevate the likelihood and intensity of systemic diseases. The presence of reactive oxygen species (ROS) and associated related oxidative stress is intricately linked to the progression and severity of periodontal inflammation. Targeted removal of local ROS may serve to attenuate inflammation, improve the unfavorable periodontal microenvironment and potentially reverse ensuing pathological cascades. These ROS scavenging nanoparticles, which possess additional characteristics such as anti-inflammation and osteogenic differentiation, are highly sought after for the treatment of periodontitis. In this study, negative charged human serum albumin-crosslinked manganese-doped self-assembling Prussian blue nanoparticles (HSA-MDSPB NPs) were fabricated. These nanoparticles demonstrate the ability to scavenge multiple ROS including superoxide anion, free hydroxyl radicals, singlet oxygen and hydrogen peroxide. Additionally, HSA-MDSPB NPs exhibit the capacity to alleviate inflammation in gingiva and alveolar bone both in vitro and in vivo. Furthermore, HSA-MDSPB NPs have been shown to play a role in promoting the polarization of macrophages from the M1 to M2 phenotype, resulting in reduced production of pro-inflammatory cytokines. More attractively, HSA-MDSPB NPs have been demonstrated to enhance cellular osteogenic differentiation. These properties of HSA-MDSPB NPs contribute to decreased inflammation, extracellular matrix degradation and bone loss in periodontal tissue. In conclusion, the multifunctional nature of HSA-MDSPB NPs provides a promising therapeutic approach for the treatment of periodontitis.

Salivary Oxidative-Antioxidant Profile Following Adjunctive Gaseous Ozone Administration in Non-Surgical Periodontal Treatment: A Randomized Controlled Trial

Background: Periodontitis is associated with increased oxidative stress, which may impair treatment outcomes. Ozone therapy has shown promise in reducing oxidative stress and improving periodontal health. This study examined the impact of adjunctive gaseous ozone administration on salivary oxidative stress markers in patients with periodontitis stages II-IV and grades A-C undergoing non-surgical periodontal treatment (NSPT). Methods: Ninety patients with periodontitis were randomly allocated to either the test group (NSPT with gaseous ozone administration) or the control group (NSPT alone) using computer-generated randomization. The OzoneDTA system was used to deliver ozone at 2100 ppm for 60 s per site once weekly for 4 weeks. Clinical periodontal parameters (probing depth [PD], clinical attachment level [CAL], plaque index [PI], gingival index [GI]) and salivary oxidative stress markers (malondialdehyde [MDA], total antioxidant capacity [TAC], superoxide dismutase [SOD]) were assessed by blinded examiners at baseline, 3, and 6 months post-treatment. Results: Mixed ANOVA revealed significant three-way interactions between time, treatment, and stage or grade for clinical and biochemical measures (p < 0.001). The test group exhibited significant improvements in TAC (mean difference: 0.45 ± 0.12 mmol/L, p = 0.002), MDA (-0.38 ± 0.09 nmol/mL, p = 0.001), and SOD (65 ± 18 U/mL, p < 0.001) compared with the control group, with more pronounced effects in stages III and IV. Large effect sizes (Cohen's d > 0.8) were observed for the test group between baseline and 6 months for all markers. Conclusions: Gaseous ozone administration as an adjunct to NSPT can effectively improve clinical periodontal parameters and salivary oxidative stress markers, particularly in stages III and IV periodontitis. The enhanced outcomes may be attributed to ozone's antimicrobial and immunomodulatory properties, which synergistically reduce oxidative stress and promote periodontal healing.

Thermo-Responsive Hydrogel Containing Microfluidic Chitosan Nanoparticles Loaded with Opuntia ficus-indica Extract for Periodontitis Treatment

Periodontitis is a chronic inflammatory disease resulting from the dysbiosis of periodontal bacteria and the host's immune response, leading to tissue degradation and sustained inflammation. Traditional treatments, such as mechanical debridement and antimicrobial agents, often fail to fully eradicate pathogenic bacteria, especially in deep periodontal pockets. Consequently, the need for novel therapeutic approaches has increased the interest in bioactive natural extracts, such as that of Opuntia ficus-indica, known for its anti-inflammatory, antioxidant, and antimicrobial properties. This study investigates the encapsulation of Opuntia ficus-indica extract in OFI-loaded chitosan nanoparticles (OFI-NPs) via ionotropic gelation using a microfluidic system, allowing precise control over nanoparticle characteristics and enhancing protection against enzymatic degradation. To achieve localized and sustained release in periodontal pockets, a thermo-responsive hydrogel comprising hyaluronic acid and Pluronic F127 (OFI@tgels) was developed. The transition of OFI@tgels from a solution at low temperatures to a solid at body temperature enables prolonged drug release at inflammation sites. The in vitro application of the optimized formulation eradicated biofilms of S. mutans, P. aeruginosa (PAO1), and P. gingivalis over 36 h and disrupted extracellular polymeric substance formation. Additionally, OFI@tgel modulated immune responses by inhibiting M1 macrophage polarization and promoting a shift to the M2 phenotype. These findings suggest that OFI@tgel is a promising alternative treatment for periodontitis, effectively reducing biofilm formation and modulating the immune response.

Nanozybiotics: Advancing Antimicrobial Strategies Through Biomimetic Mechanisms

Infectious diseases caused by bacterial, viral, and fungal pathogens present significant global health challenges. The rapid emergence of antimicrobial resistance exacerbates this issue, leading to a scenario where effective antibiotics are increasingly scarce. Traditional antibiotic development strategies are proving inadequate against the swift evolution of microbial resistance. Therefore, there is an urgent need to develop novel antimicrobial strategies with mechanisms distinct from those of existing antibiotics. Nanozybiotics, which are nanozyme-based antimicrobials, mimic the catalytic action of lysosomal enzymes in innate immune cells to kill infectious pathogens. This review reinforces the concept of nanozymes and provides a comprehensive summary of recent research advancements on potential antimicrobial candidates. Initially, nanozybiotics are categorized based on their activities, mimicking either oxidoreductase-like or hydrolase-like functions, thereby highlighting their superior mechanisms in combating antimicrobial resistance. The review then discusses the progress of nanozybiotics in treating bacterial, viral, and fungal infections, confirming their potential as novel antimicrobial candidates. The translational potential of nanozybiotic-based products, including hydrogels, nanorobots, sprays, bandages, masks, and protective clothing, is also considered. Finally, the current challenges and future prospects of nanozybiotic-related products are explored, emphasizing the design and antimicrobial capabilities of nanozybiotics for future applications.

Antibacterial Activity of Cissus quadrangularis (Veldt Grape) Against Porphyromonas gingivalis, a Keystone Pathogen in Periodontal Disease: An In Vitro Study

BACKGROUND

Porphyromonas gingivalis, a keystone pathogen and one of the primary pathogens responsible for periodontitis, leads to a chronic inflammatory condition that destroys the periodontal tissues and ultimately results in tooth loss. While conventional non-surgical therapy combined with antibiotics and local drug delivery systems are commonly used to treat periodontitis, certain medicinal herbs have also demonstrated efficacy in its prevention. Cissus quadrangularis L. (CQ), a perennial plant from the Vitaceae family, is widely recognized and used as a medicinal herb in many tropical countries, predominantly in India, Sri Lanka, Thailand, Java, West Africa, and the Philippines.

AIM

The aim of the study was to determine the antibacterial activity of CQ against the periodontal keystone pathogen P. gingivalis.

METHOD

Aqueous and ethanolic extracts of CQ were prepared using a Soxhlet extractor. The antibacterial effectiveness of these extracts against the periodontal pathogen P. gingivalis was evaluated at different concentrations, and the minimal inhibitory concentration (MIC) was determined using broth microdilution.

RESULTS

The ethanolic extract of CQ mixed with 10% dimethyl sulfoxide (DMSO) showed higher inhibition compared to the aqueous extract of CQ against P. gingivalis.

CONCLUSION

Our study revealed the potent inhibitory effects of CQ against P. gingivalis. Both aqueous and ethanolic extracts displayed MIC values of 500 µg/mL. Notably, the ethanolic extract of CQ, dissolved in 10% DMSO, demonstrated superior efficacy with a lower IC50 value of 194.36 µg/mL. These findings indicate promising potential for CQ in the management of periodontal disease.

Adjunctive antimicrobial photodynamic therapy for treating periodontal and peri-implant diseases

BACKGROUND

Periodontitis and peri-implant diseases are chronic inflammatory conditions occurring in the mouth. Left untreated, periodontitis progressively destroys the tooth-supporting apparatus. Peri-implant diseases occur in tissues around dental implants and are characterised by inflammation in the peri-implant mucosa and subsequent progressive loss of supporting bone. Treatment aims to clean the pockets around teeth or dental implants and prevent damage to surrounding soft tissue and bone, including improvement of oral hygiene, risk factor control (e.g. encouraging cessation of smoking) and surgical interventions. The key aspect of standard non-surgical treatment is the removal of the subgingival biofilm using subgingival instrumentation (SI) (also called scaling and root planing). Antimicrobial photodynamic therapy (aPDT) can be used an adjunctive treatment to SI. It uses light energy to kill micro-organisms that have been treated with a light-absorbing photosensitising agent immediately prior to aPDT.

OBJECTIVES

To assess the effects of SI with adjunctive aPDT versus SI alone or with placebo aPDT for periodontitis and peri-implant diseases in adults.

SEARCH METHODS

We searched the Cochrane Oral Health Trials Register, CENTRAL, MEDLINE, Embase, two other databases and two trials registers up to 14 February 2024.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) (both parallel-group and split-mouth design) in participants with a clinical diagnosis of periodontitis, peri-implantitis or peri-implant disease. We compared the adjunctive use of antimicrobial photodynamic therapy (aPDT), in which aPDT was given after subgingival or submucosal instrumentation (SI), versus SI alone or a combination of SI and a placebo aPDT given during the active or supportive phase of therapy.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures, and we used GRADE to assess the certainty of the evidence. We prioritised six outcomes and the measure of change from baseline to six months after treatment: probing pocket depth (PPD), bleeding on probing (BOP), clinical attachment level (CAL), gingival recession (REC), pocket closure and adverse effects related to aPDT. We were also interested in change in bone level (for participants with peri-implantitis), and participant satisfaction and quality of life.

MAIN RESULTS

We included 50 RCTs with 1407 participants. Most studies used a split-mouth study design; only 18 studies used a parallel-group design. Studies were small, ranging from 10 participants to 88. Adjunctive aPDT was given in a single session in 39 studies, in multiple sessions (between two and four sessions) in 11 studies, and one study included both single and multiple sessions. SI was given using hand or power-driven instrumentation (or both), and was carried out prior to adjunctive aPDT. Five studies used placebo aPDT in the control group and we combined these in meta-analyses with studies in which SI alone was used. All studies included high or unclear risks of bias, such as selection bias or performance bias of personnel (when SI was carried out by an operator aware of group allocation). We downgraded the certainty of all the evidence owing to these risks of bias, as well as for unexplained statistical inconsistency in the pooled effect estimates or for imprecision when evidence was derived from very few participants and confidence intervals (CI) indicated possible benefit to both intervention and control groups. Adjunctive aPDT versus SI alone during active treatment of periodontitis (44 studies) We are very uncertain whether adjunctive aPDT during active treatment of periodontitis leads to improvement in any clinical outcomes at six months when compared to SI alone: PPD (mean difference (MD) 0.52 mm, 95% CI 0.31 to 0.74; 15 studies, 452 participants), BOP (MD 5.72%, 95% CI 1.62 to 9.81; 5 studies, 171 studies), CAL (MD 0.44 mm, 95% CI 0.24 to 0.64; 13 studies, 414 participants) and REC (MD 0.00, 95% CI -0.16 to 0.16; 4 studies, 95 participants); very low-certainty evidence. Any apparent differences between adjunctive aPDT and SI alone were not judged to be clinically important. Twenty-four studies (639 participants) observed no adverse effects related to aPDT (moderate-certainty evidence). No studies reported pocket closure at six months, participant satisfaction or quality of life. Adjunctive aPDT versus SI alone during supportive treatment of periodontitis (six studies) We were very uncertain whether adjunctive aPDT during supportive treatment of periodontitis leads to improvement in any clinical outcomes at six months when compared to SI alone: PPD (MD -0.04 mm, 95% CI -0.19 to 0.10; 3 studies, 125 participants), BOP (MD 4.98%, 95% CI -2.51 to 12.46; 3 studies, 127 participants), CAL (MD 0.07 mm, 95% CI -0.26 to 0.40; 2 studies, 85 participants) and REC (MD -0.20 mm, 95% CI -0.48 to 0.08; 1 study, 24 participants); very low-certainty evidence. These findings were all imprecise and included no clinically important benefits for aPDT. Three studies (134 participants) reported adverse effects: a single participant developed an abscess, though it is not evident whether this was related to aPDT, and two studies observed no adverse effects related to aPDT (moderate-certainty evidence). No studies reported pocket closure at six months, participant satisfaction or quality of life.

AUTHORS' CONCLUSIONS

Because the certainty of the evidence is very low, we cannot be sure if adjunctive aPDT leads to improved clinical outcomes during the active or supportive treatment of periodontitis; moreover, results suggest that any improvements may be too small to be clinically important. The certainty of this evidence can only be increased by the inclusion of large, well-conducted RCTs that are appropriately analysed to account for change in outcome over time or within-participant split-mouth study designs (or both). We found no studies including people with peri-implantitis, and only one study including people with peri-implant mucositis, but this very small study reported no data at six months, warranting more evidence for adjunctive aPDT in this population group.

Effectiveness of probiotics compared to antibiotics to treat periodontal disease: Systematic review

OBJECTIVES

Probiotics are promising adjuncts to non-surgical periodontal therapy (scaling and root planing (SRP)) for managing gingival and periodontal diseases. Probiotics are considered alternatives to antibiotics, especially with the emergence of antimicrobial resistance. Hence, the present systematic review aims to generate evidence on the role of probiotics compared to antimicrobial agents for managing periodontal diseases (gingivitis and periodontitis).

METHOD

Six electronic databases (PubMed, SCOPUS, Web of Science, EBSCO, Cochrane, Clinical Trial Registry) were searched to collect studies comparing the effect of probiotics with antibiotics for periodontal disease. In total, 5530 articles were retrieved from all databases, of which 1891 were included for title and abstract screening. After screening, a total of ten clinical studies were included for data extraction and analysis. Probing pocket depth (PPD), Clinical attachment loss (CAL), bleeding on probing (BOP), plaque index (PI), gingival index (GI), and microbial profile were recorded.

RESULTS

Probiotics showed a significant reduction in the PPD and CAL compared to antibiotics. Antibiotics were more effective in reducing the PI and GI. A combination of probiotics and antibiotics superior compared to probiotics and antibiotics alone.

CONCLUSION

Probiotics can be used as an alternative to antibiotics, however, a combination is more effective for managing periodontal disease.

Highly Crystalline Copper Aluminum-Layered Double Hydroxides with Intrinsic Fenton-Like Catalytic Activity for Robust Oral Health Management

As the main challenge of dental healthcare, oral infectious diseases are highly associated with the colonization of pathogenic microbes. However, current antibacterial treatments in the field of stomatology still lack a facile, safe, and universal approach. Herein, we report the controllable synthesis of copper aluminum-layered double hydroxides (CuAl-LDHs) with high Fenton-like catalytic activity, which can be utilized in the treatment of oral infectious diseases with negligible side effects. Our strategy can efficiently avoid the unwanted doping of other divalent metal ions in the synthesis of Cu-contained LDHs and result in the formation of binary CuAl-LDHs with high crystallinity and purity. Evidenced by experimental and theoretical results, CuAl-LDHs exhibit excellent catalytic ability toward the ·OH generation in the presence of H2O2 and hold strong affinity toward bacteria, endowing them with great catalytic sterilization against both Gram-positive and Gram-negative bacteria. As expected, these CuAl-LDHs provide outstanding treatments for mucosal infection and periodontitis by promoting wound healing and remodeling of the periodontal microenvironment. Moreover, toxicity investigation demonstrates the overall safety. Accordingly, the current study not only provides a convenient and economic strategy for treating oral infectious diseases but also extends the development of novel LDH-based Fenton or Fenton-like antibacterial reagents for further biomedical applications.

Sulfated Chitosan-Modified CuS Nanocluster: A Versatile Nanoformulation for Simultaneous Antibacterial and Bone Regenerative Therapy in Periodontitis

Periodontitis, a prevalent chronic inflammatory disease worldwide, is triggered by periodontopathogenic bacteria, resulting in the progressive destruction of periodontal tissue, particularly the alveolar bone. To effectively address periodontitis, this study proposed a nanoformulation known as CuS@MSN-SCS. This formulation involves coating citrate-grafted copper sulfide (CuS) nanoparticles with mesoporous silica (MSNs), followed by surface modification using amino groups and sulfated chitosan (SCS) through electrostatic interactions. The objective of this formulation is to achieve efficient bacteria removal by inducing ROS signaling pathways mediated by Cu2+ ions. Additionally, it aims to promote alveolar bone regeneration through Cu2+-induced pro-angiogenesis and SCS-mediated bone regeneration. As anticipated, by regulating the surface charges, the negatively charged CuS nanoparticles capped with sodium citrate were successfully coated with MSNs, and the subsequent introduction of amine groups using (3-aminopropyl)triethoxysilane was followed by the incorporation of SCS through electrostatic interactions, resulting in the formation of CuS@MSN-SCS. The developed nanoformulation was verified to not only significantly exacerbate the oxidative stress of Fusobacterium nucleatum, thereby suppressing bacteria growth and biofilm formation in vitro, but also effectively alleviate the inflammatory response and promote alveolar bone regeneration without evident biotoxicity in an in vivo rat periodontitis model. These findings contribute to the therapeutic effect on periodontitis. Overall, this study successfully developed a nanoformulation for combating bacteria and facilitating alveolar bone regeneration, demonstrating the promising potential for clinical treatment of periodontitis.

Combination of Neovestitol and Vestitol Modifies the Profile of Periodontitis-Related Subgingival Multispecies Biofilm

The aim of this study was to evaluate the effect of the combination of neovestitol-vestitol (CNV) compounds obtained from Brazilian red propolis on the microbiological profile of a mature multispecies subgingival biofilm. The biofilm with 32 bacterial species associated with periodontitis was formed for seven days using a Calgary device. Treatment with CNV (1600, 800, 400, and 200 μg/mL), amoxicillin (54 μg/mL), and vehicle control was performed for 24 h on the last day of biofilm formation. Biofilm metabolic activity and DNA-DNA hybridization (checkerboard) assays were performed. The groups treated with CNV 1600 and amoxicillin reduced 25 and 13 species, respectively, compared to the control vehicle treatment (p ≤ 0.05); both reduced P. gingivalis, while only CNV reduced T. forsythia. When the data from the two treatments (CNV and AMOXI) were compared, a statistically significant difference was observed in 13 species, particularly members of Socransky's orange complex. Our results showed that CNV at 1600 μg/mL showed the best results regarding the metabolic activity of mature biofilms and obtained a reduction in species associated with the disease, such as T. forsythia, showing a better reduction than amoxicillin. Therefore, CNV seems to be a promising alternative to eradicate biofilms and reduce their pathogenicity.

Advances in Hydrogels for Periodontitis Treatment

Periodontitis is a common condition characterized by a bacterial infection and the disruption of the body's immune-inflammatory response, which causes damage to the teeth and supporting tissues and eventually results in tooth loss. Current therapy involves the systemic and local administration of antibiotics. However, the existing treatments cannot exert effective, sustained release and maintain an effective therapeutic concentration of the drug at the lesion site. Hydrogels are used to treat periodontitis due to their low cytotoxicity, exceptional water retention capability, and controlled drug release profile. Hydrogels can imitate the extracellular matrix of periodontal cells while offering suitable sites to load antibiotics. This article reviews the utilization of hydrogels for periodontitis therapy based on the pathogenesis and clinical manifestations of the disease. Additionally, the latest therapeutic strategies for smart hydrogels and the main techniques for hydrogel preparation have been discussed. The information will aid in designing and preparing future hydrogels for periodontitis treatment.

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.

Injectable hydrogels activated with copper sulfide nanoparticles for enhancing spatiotemporal sterilization and osteogenesis in periodontal therapy

Developing biomaterials capable of promoting bone regeneration in bacteria-infected sites is of utmost urgency for periodontal disease therapies. Here we produce a hybrid hydrogel by integrating CuS nanoparticles (CuSNPs), which could kill bacteria through photothermal therapy (PTT) triggered by a near infrared (NIR) light, and a gelatin methacryloyl (GelMA) hydrogel, which is injectable and biocompatible. Specifically, CuSNPs were precipitated by chitosan (CS) firstly, then grafted with methacrylic anhydride (MA) to form CuSNP@CS-MA, which was photo-crosslinked with GelMA to synthesize hybrid hydrogels (GelMA/CuSNP). The hybrid hydrogels exhibited a broad-spectrum antibacterial property that could be spatiotemprorally manipulated through applying a NIR light. Their mechanical properties were adjustable by controlling the concentration of CuSNPs, enabling the hydrogels to become more adapted to the oral diseases. Meanwhile, the hybrid hydrogels showed good cytocompatibility in vitro and improved hemostasis in vivo. Moreover, they accelerated alveolar osteogenesis and vascular genesis, successfully treating periodontis in four weeks in a rat model. GelMA/CuSNP hydrogels showed a broad-spectrum sterilization ability via PTT in vitro and outstanding antibacterial property in vivo, suggesting that the hybrid hydrogels could function in the challenging, bacteria-rich, oral environment. Such injectable hybrid hydrogels, capable of achieving both facilitated osteogenesis and NIR-inducible sterilization, represent a new biomaterial for treating periodontitis.

Cuttlefish-Inspired Photo-Responsive Antibacterial Microparticles with Natural Melanin Nanoparticles Spray

Topical antibiotics can be utilized to treat periodontitis, while their delivery stratagems with controlled release and long-lasting bactericidal inhibition are yet challenging. Herein, inspired by the defensive behavior of cuttlefish expelling ink, this work develops innovative thermal-responsive melanin-integrated porous microparticles (MPs) through microfluidic synthesis for periodontitis treatment. These MPs are composed of melanin nanoparticles (NPs), poly(N-isopropylacrylamide) (PNIPAM), and agarose. Benefiting from the excellent biocompatibility and large surface area ratio of MPs, they can deliver abundant melanin NPs. Under near-infrared irradiation, the melanin NPs can convert photo energy into thermal energy. This leads to agarose melting and subsequent shrinkage of the microspheres induced by pNIPAM, thereby facilitating the release of melanin NPs. In addition, the released melanin NPs can serve as a highly effective photothermal agent, displaying potent antibacterial activity against porphyromonas gingivalis and possessing natural anti-inflammatory properties. These unique characteristics are further demonstrated through in vivo experiments, showing the antibacterial effects in the treatment of infected wounds and periodontitis. Therefore, the catfish-inspired photo-responsive antibacterial MPs with controlled-release drug delivery hold tremendous potential in clinical antibacterial applications.

Histological evaluation of nonsurgical periodontal treatment with and without the use of sodium hypochlorite / amino acids and cross-linked hyaluronic acid gels in dogs

OBJECTIVES

To evaluate periodontal wound healing following scaling and root planing (SRP) in conjunction with the application of sodium hypochlorite/amino acids and cross-linked hyaluronic acid (xHyA) gels in dogs.

MATERIALS AND METHODS

In four beagle dogs, 2-wall intrabony defects were created and metal strips were placed around the teeth. Clinical parameters were measured 4 weeks after plaque accumulation. The experimental root surfaces were subjected to SRP with either the subgingival application of a sodium hypochlorite/amino acid gel and a xHyA gel (test group) or SRP alone (control group) using a split-mouth design. Clinical parameters were re-evaluated at 6 weeks. The animals were sacrificed at 8 weeks for histological analysis.

RESULTS

The test group showed significant improvements in all clinical parameters compared to the control group. Histologically, the test group exhibited statistically significantly greater new bone formation [i.e., length of newly formed bone, new bone area] compared with the control group (p < 0.05). Furthermore, statistically significantly greater formation of new attachment [i.e., linear length of new cementum adjacently to newly formed bone with inserting collagen fibers] and new cementum was detected in the test group compared with the control group at 8 weeks (p < 0.05 and p < 0.01, respectively).

CONCLUSION

The adjunctive subgingival application of sodium hypochlorite/amino acid and xHyA gels to SRP offers an innovative novel approach to enhance periodontal wound healing/regeneration.

CLINICAL RELEVANCE

The present findings have for the first-time shown histologic evidence for periodontal regeneration in support of this novel treatment modality.

Lactobacillus reuteri for chronic periodontitis: focus on underlying mechanisms and future perspectives

Chronic periodontitis is a common oral disorder caused by pathogenic bacteria. Despite the wide use of antibiotics as the conventional adjunctive treatment, the challenges of increased antibiotic resistance and limited therapeutic effect receive considerable attention and the developments of alternative treatments gain increasing consideration. Growing evidence showed that Lactobacillus reuteri (LR) may represent a promising alternative adjunct for chronic periodontitis. It can attenuate inflammation and reduce tissue disruption. LR-assisted treatment has been shown to be effective and relatively safe in multiple clinical trials, and accumulating evidence suggests its significant biological roles. In the current review, we focus on capturing the underlying mechanisms of LR involved in chronic periodontitis, thereby representing a scientific foundation for LR-assisted therapy. Furthermore, we point out the challenges and future directions for further clinical trials to improve the clinical applicability for LR.

Control of tissue homeostasis by the extracellular matrix: Synthetic heparan sulfate as a promising therapeutic for periodontal health and bone regeneration

Proteoglycans are core proteins associated with carbohydrate/sugar moieties that are highly variable in disaccharide composition, which dictates their function. These carbohydrates are named glycosaminoglycans, and they can be attached to proteoglycans or found free in tissues or on cell surfaces. Glycosaminoglycans such as hyaluronan, chondroitin sulfate, dermatan sulfate, keratan sulfate, and heparin/heparan sulfate have multiple functions including involvement in inflammation, immunity and connective tissue structure, and integrity. Heparan sulfate is a highly sulfated polysaccharide that is abundant in the periodontium including alveolar bone. Recent evidence supports the contention that heparan sulfate is an important player in modulating interactions between damage associated molecular patterns and inflammatory receptors expressed by various cell types. The structure of heparan sulfate is reported to dictate its function, thus, the utilization of a homogenous and structurally defined heparan sulfate polysaccharide for modulation of cell function offers therapeutic potential. Recently, a chemoenzymatic approach was developed to allow production of many structurally defined heparan sulfate carbohydrates. These oligosaccharides have been studied in various pathological inflammatory conditions to better understand their function and their potential application in promoting tissue homeostasis. We have observed that specific size and sulfation patterns can modulate inflammation and promote tissue maintenance including an anabolic effect in alveolar bone. Thus, new evidence provides a strong impetus to explore heparan sulfate as a potential novel therapeutic agent to treat periodontitis, support alveolar bone maintenance, and promote bone formation.

Adjunctive effect of 470-nm and 630-nm light-emitting diode irradiation in experimental periodontitis treatment: a preclinical study

PURPOSE

This study investigated the adjunctive effect of light-emitting diodes (LEDs) in the treatment of experimental periodontitis.

METHODS

Experimental periodontitis was induced by placing ligatures around the mandibular second, third, and fourth premolars of 6 beagles for 3 months. After ligature removal, periodontitis progressed spontaneously for 2 months. The animals' hemimandibles were allocated among the following 3 groups: 1) no treatment (control), 2) scaling and root planing (SRP), and 3) SRP with LED irradiation at 470-nm and 630-nm wavelengths (SRP/LED). The probing pocket depth (PPD) and gingival recession (GR) were measured at baseline, 6 weeks, and 12 weeks. The clinical attachment level (CAL) was calculated. After 12 weeks, histological and histomorphometric assessments were performed. The distances from the gingival margin to the apical extent of the junctional epithelium (E) and to the connective tissue (CT) attachment were measured, as was the total length of soft tissue (ST).

RESULTS

PPD and CAL increased at 12 weeks compared with baseline in the control group (6.31±0.43 mm to 6.93±0.50 mm, and 6.46±0.60 mm to 7.61±0.78 mm, respectively). PPD and CAL decreased at 12 weeks compared with baseline in the SRP group (6.01±0.59 to 4.81±0.65 mm, and 6.51±0.98 to 5.39±0.93 mm, respectively). PPD and CAL decreased at 12 weeks compared with baseline in the SRP/LED group (6.03±0.39 to 4.46±0.47 mm, and 6.11±0.47 to 4.78±0.57 mm, respectively). The E/ST and CT/ST ratios significantly differed among the 3 groups (P<0.05). The clinical parameters and histologic findings demonstrated that 470-nm and 630-nm wavelength LED irradiation accompanying SRP could improve treatment results.

CONCLUSIONS

Within the study limitations, 470 nm and 630 nm wavelength LED irradiation might provide additional benefits for periodontitis treatment.

Microcin C7-laden modified gelatin based biocomposite hydrogel for the treatment of periodontitis

Periodontitis is an oral disease with the highest incidence globally, and plaque control is the key to its treatment. In this study, Microcin C7 was used to treat periodontitis, and a novel injectable temperature-sensitive sustained-release hydrogel was synthesized as an environmentally sensitive carrier for drug delivery. First, modified gelatin was formed from gelatin and glycidyl methacrylate. Then, Microcin C7-laden hydrogel was formed from cross-linking with double bonds between modified gelatin, N-isopropyl acrylamide, and 2-Methacryloyloxyethyl phosphorylcholine through radical polymerization, and the model drug Microcin C7 was loaded by electrostatic adsorption. The hydrogel has good temperature sensitivity, self-healing, and injectable properties. In vitro results showed that the hydrogel could slowly and continuously release Microcin C7 with good biocompatibility and biodegradability, with a remarkable antibacterial effect on Porphyromonas gingivalis. It also confirmed the antibacterial and anti-inflammatory effects of Microcin C7-laden hydrogel in a periodontitis rat model. The results showed that Microcin C7-laden hydrogel is a promising candidate for local drug delivery systems in periodontitis.

Effects of Antimicrobial Photosensitizers of Photodynamic Therapy (PDT) to Treat Periodontitis

Antimicrobial photodynamic therapy or aPDT is an alternative therapeutic approach in which lasers and different photosensitizing agents are used to eradicate periodontopathic bacteria in periodontitis. Periodontitis is a localized infectious disease caused by periodontopathic bacteria and can destroy bones and tissues surrounding and supporting the teeth. The aPDT system has been shown by in vitro studies to have high bactericidal efficacy. It was demonstrated that aPDT has low local toxicity, can speed up dental therapy, and is cost-effective. Several photosensitizers (PSs) are available for each type of light source which did not induce any damage to the patient and are safe. In recent years, significant advances have been made in aPDT as a non-invasive treatment method, especially in treating infections and cancers. Besides, aPDT can be perfectly combined with other treatments. Hence, this survey focused on the effectiveness and mechanism of aPDT of periodontitis by using lasers and the most frequently used antimicrobial PSs such as methylene blue (MB), toluidine blue ortho (TBO), indocyanine green (ICG), malachite green (MG) (Triarylmethanes), erythrosine dyes (ERY) (Xanthenes dyes), rose bengal (RB) (Xanthenes dyes), eosin-Y (Xanthenes dyes), radachlorin group and curcumin. The aPDT with these PSs can reduce pathogenic bacterial loads in periodontitis. Therefore, it is clear that there is a bright future for using aPDT to fight microorganisms causing periodontitis.

A telluroviologen-anchored tetraphenylporphyrin as sonosensitizer for periodontitis sonodynamic therapy

Periodontitis is a chronic disease caused by bacteria (e.g. Porphyromonas gingivalis, P.gingivalis) that currently lacks effective non-invasive treatment options. Sonodynamic therapy (SDT) is an emerging non-invasive antimicrobial therapeutic strategy. Since ultrasonic tooth cleaning is widely used in dental treatments, SDT has significant potential for the facile implementation of treat periodontitis. However, hypoxia in periodontitis severely limits the effectiveness of traditional sonosensitizers. To address this issue, we have developed a new sonosensitizer termed as TPP-TeV, which combines the traditional sonosensitizer tetraphenylporphyrin (TPP) with a new photosensitizer telluroviologen (TeV). Under ultrasound radiation, TPP-TeV can produce numerous cationic free radicals (TPP-TeV•), which subsequently generate ROS free radicals (O2•-, •OH) efficiently via electron transfer mechanism, resulting in the effective killing of anaerobic P.gingivalis both in vivo and in vitro. As a result, the dental environment is improved, and the inhibition rate of alveolar bone loss reaches 80 %. The introduction of tellurium into the viologen molecule induces changes in its reduction potential, resulting in increased rigidity of the molecule. This modification systematically reduces the biotoxicity of our novel sonosensitizer by 75 % at 50 μM based on bacterial experiments. These promising findings could potentially establish new options for sonodynamic therapy (SDT) in periodontitis clinical treatments.

Antimicrobial photocatalysis using bio-hydrothermally synthesized Zinc oxide nanoparticles in the management of periodontitis: a prospective split-mouth, double-blind, randomized, controlled clinical trial

BACKGROUND

The antimicrobial activity of metallic nanoparticles (NPs) has been confirmed to fight a broad spectrum of microorganisms, through antimicrobial effects that are amplified when these particles are irradiated with light of the proper wavelength. This is the first study to use phytoconjugated Zinc oxide (ZnO) NPs containing traces of active biomolecules derived from Emblica officinalis (E. officinalis) plant extract in antimicrobial photocatalysis (PCT) during non-surgical periodontal therapy.

OBJECTIVES

This study aimed to evaluate the effects of repeated PCT application in the treatment of periodontitis, using a gel containing bio-hydrothermally synthesized ZnO NPs and visible light as an adjunct to scaling and root planing (SRP).

METHODOLOGY

In total, 16 systemically healthy volunteers with stage 3 grade B generalized periodontitis were recruited for this prospective double blind, randomized placebo-controlled trial. After receiving SRP, the subjects received the following interventions in a split-mouth design at baseline, 1 week and 1 month: Group 1 - Placebo gel + Sham PCT; Group 2 - Nano ZnO gel + Sham PCT; Group 3 - Placebo gel + PCT; and Group 4 - Nano ZnO gel + PCT. The site-specific profile of Porphyromonas gingivalis in the subgingival plaque and clinical parameters (Plaque Index, Gingival Index, Gingival Bleeding Index, Probing pocket Depth and Clinical Attachment Level) were assessed at baseline, 1 month and 3 months.

RESULTS

All interventions tested caused participants' clinical and microbiological parameters to generally improve after 3 months. Subjects who received the Nano ZnO gel + PCT combination showed a sustained and progressive improvement in their treatment outcomes, a result that presented statistically significant differences from the outcomes obtained through the remaining interventions, at all time points during the study period.

CONCLUSIONS

The repeated application of PCT using bio-hydrothermally synthesized ZnO NPs can effectively complement SRP in the non-surgical treatment of Periodontitis.

Biocompatible Nanostructured Silver-Incorporated Implant Surfaces Show Effective Antibacterial, Osteogenic, and Anti-Inflammatory Effects in vitro and in Rat Model

Introduction

Titanium (Ti) and its alloys are widely utilized in endosseous implants. However, their clinical efficacy is marred by complications arising from bacterial infections owing to their inadequate antibacterial properties. Consequently, enhancing the antibacterial attributes of implant surfaces stands as a pivotal objective in the realm of implantable materials research.

Methods

In this study, we employed sequential anodization and plasma immersion ion implantation (PIII) technology to fabricate a silver-embedded sparsely titania nanotube array (SNT) on the near-β titanium alloy Ti-5Zr-3Sn-5Mo-15Nb (TLM) implants. The surface characteristics, antimicrobial properties, biocompatibility, and osteogenic activity of the silver-nanomodified SNT implant (SNT Ag) surface, alongside peri-implant inflammatory responses, were meticulously assessed through a combination of in vitro and in vivo analyses.

Results

Compared with polished TLM and SNT, the silver-embedded SNT (SNT Ag) surface retained the basic shape of nanotubes and stably released Ag+ at the ppm level for a long time, which demonstrated an effective inhibition and bactericidal activity against Staphylococcus aureus (SA) while maintaining ideal cytocompatibility. Additionally, the subtle modifications in nanotubular topography induced by silver implantation endowed SNT Ag with enhanced osteogenic activity and mitigated inflammatory capsulation in soft tissue peri-implants in a rat model.

Conclusion

Incorporating a silver-embedded SNT array onto the implant surface demonstrated robust antibacterial properties, impeccable cytocompatibility, exceptional osteogenic activity, and the potential to prevent inflammatory encapsulation around the implant site. The Silver-PIII modification strategy emerges as a highly promising approach for surface applications in endosseous implants and trans-gingival implant abutments.

Susceptibility of periodontal pathogens to a novel target-specific drug delivery system containing self-nanoemulsifying curcumin: An in vitro study

Background

Long-term use of many classic chemotherapeutic agents as adjuncts in the management of periodontitis has adverse complications, leading to seeking out naturopathic remedies. Although curcumin has been investigated in managing periodontitis, its therapeutic benefits have not been fully explored due to its limited solubility in an aqueous medium. This study aimed to develop a novel target-specific drug delivery system containing 1% self-nanoemulsifying curcumin (SNEC) in a hydroxypropylmethylcellulose (HPMC) matrix and evaluate the susceptibility of periodontal pathogens to this system in vitro.

Methods

Its antibacterial activity against Tannerella forsythia, Porphyromonas gingivalis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans was evaluated and compared to pure nano-curcumin and SNEC alone by estimating their minimum inhibitory concentrations (MIC).

Results

The antibacterial activity of pure nano-curcumin, SNEC, and SNEC in HPMC against the four periodontal pathogens evaluated in terms of MIC was recorded in the range of 0.2‒0.4, 0.4‒0.8, and 0.2‒0.8 µg/mL, respectively. However, the MIC of all three curcumin formulations against the periodontal pathogens tested was higher than that of the standard moxifloxacin. While both pure nano-curcumin and SNEC showed increasing values of inhibition zones with increasing concentrations on disk diffusion assay, lower concentrations of SNEC in HPMC did not show a zone of inhibition against the tested pathogens.

Conclusion

The novel delivery system containing SNEC in HPMC may be a potential adjunct in managing periodontitis due to its probable sustained antimicrobial activity against the tested periodontal pathogens.

An injectable photopolymerizable chitosan hydrogel doped anti-inflammatory peptide for long-lasting periodontal pocket delivery and periodontitis therapy

Periodontitis is a common chronic inflammatory disease caused by plaque that leads to alveolar bone resorption and tooth loss. Inflammation control and achieving better tissue repair are the key to periodontitis treatment. In this study, human β-Defensin 1 short motif Pep-B with inflammation inhibition and differentiation regulation properties, is firstly used in the treatment of periodontitis, and an injectable photopolymerizable Pep-B/chitosan methacryloyl composite hydrogel (CMSA/Pep-B) is constructed. We confirm that Pep-B improves inflammation, and restores osteogenic behavior and function of injured stem cells. CMSA/Pep-B has good injectability, fluidity and photopolymerizability, and can sustainably release Pep-B to maintain drug concentration in periodontal pockets. Furthermore, animal experiments showed that CMSA/Pep-B significantly ameliorated the inflammation of the periodontium and reduced the alveolar bone loss by decreasing inflammatory infiltration, osteoclast formation and collagen destruction. In conclusion, CMSA/Pep-B is envisaged to be a novel bioactive material or therapeutic drug for treating periodontitis.

Effect of Curcumin gel on inflammatory and anti-inflammatory biomarkers in experimental induced periodontitis in rats: a biochemical and immunological study

This study aimed to determine the effect of local application of curcumin gels as adjunct to scaling and root planing (SRP) on the inflammatory biomarkers matrix metalloproteinase-8 (MMP-8), interleukin-6 (IL-6), C-reactive protein (CRP), and alkaline phosphatase (ALP), and the anti-inflammatory biomarker interleukin-10 (IL-10) in rats with experimentally induced periodontitis. Fifty-five adult Wistar rats with experimentally induced periodontitis were randomly divided into four groups: 15 rats received SRP + curcumin gel (CU), 15 rats received SRP + Tetracycline gel (Tet), 15 rats were treated with SRP alone, and 5 rats had experimental periodontitis without treatment (EP). Five systemically healthy rats without experimental periodontitis were used as the controls. Blood samples were collected by cardiac puncture from all groups after 2, 4, and 6 weeks of therapy. Biomarker levels determined by enzyme-linked immunosorbent assay (ELISA) and, ANOVA were used to compare the study groups. The results showed a significant increase in pro-inflammatory biomarkers and a significant decrease in anti-inflammatory biomarkers in the EP group compared with the control group (p < 0.05). The local application of curcumin or tetracycline gels resulted in a significant reduction in all inflammatory biomarkers at all periods of examination compared to the EP group. IL-10 levels gradually increased after 2 weeks, peaked at 4 weeks, and then decreased after 6 weeks, however, Tet showed statistically significant improvement compared to CU (p < 0.05). Adjunctive application of CU gel was as effective as Tet gel in the treatment of EP in rats by reducing inflammatory biomarkers and enhancing anti-inflammatory cytokines.

Clostridium butyricum MIYAIRI 588 alleviates periodontal bone loss in mice with diabetes mellitus

The gut microbiota is a bridge linking periodontitis and systemic diseases, such as diabetes mellitus (DM). The probiotic Clostridium butyricum MIYAIRI 588 (CBM588) is reportedly an effective therapeutic approach for gut dysbiosis. Here, in a mouse model, we explored the therapeutic effect of CBM588 on periodontal bone destruction in DM and DM-associated periodontitis (DMP), as well as the underlying mechanism. Micro-computed tomography revealed that DM and DMP both aggravated periodontal bone destruction, which was alleviated by intragastric supplementation with CBM588. Moreover, 16S rRNA sequencing and untargeted metabolite analysis indicated that CBM588 ameliorated DMP-triggered dysbiosis and led to reduced oxidative stress associated with elevated 4-hydroxybenzenemethanol (4-HBA) in serum. Furthermore, in vitro and in vivo experiments found that the metabolite 4-HBA promoted nuclear factor erythroid 2-related factor 2 (Nrf2) signaling activation and modulated the polarization of macrophages, thus ameliorating inflammatory bone destruction in DMP. Our study demonstrates the protective effects of CBM588 in DM-induced mice, with and without ligature-induced periodontitis. The mechanism involves regulation of the gut microbiota and restoration of the integrity of the gut barrier to alleviate oxidative damage by elevating serum 4-HBA. This study suggests the possibility of CBM588 as a therapeutic adjuvant for periodontal treatment in diabetes patients.

Five-year radiological findings from a randomized controlled trial of four periodontitis treatment strategies

Radiographic findings from long-term studies of periodontitis treatment have rarely been reported. Although bone destruction is a prominent feature of periodontitis, the long-term effect on alveolar bone levels of different treatment strategies, with or without adjunctive metronidazole (MTZ), has not been reported. We investigated the 5-year radiographic outcome of therapy in patient groups treated with conventional scaling and root planing (SRP) or same-day full-mouth disinfection (FDIS), with or without adjunctive MTZ. Following a 3-month oral hygiene phase, 184 periodontitis patients were randomly allocated to one of four treatment regimens: (i) FDIS+MTZ; (ii) FDIS+placebo; (iii) SRP+MTZ; or (iv) SRP+placebo. Following active treatment, patients received biannual maintenance. In total, 161 patients (87.5%) completed the 5-year follow-up examination, at which the radiographic bone level (RBL), clinical attachment level, probing pocket depth, presence of plaque, and bleeding were recorded again. At the 5-year follow up examination, minor radiological bone loss was observed in the intervention groups FDIS+placebo, SRP+MTZ, and SRP+placebo; by contrast, the FDIS+MTZ group did not show any change in RBL. Full-mouth disinfection did not generally perform better than conventional SRP performed over a period of 2 to 4 weeks.

Blue Light-Emitting Diode Irradiation Without a Photosensitizer Alters Oral Microbiome Composition of Ligature-Induced Periodontitis in Mice

Objective: This study investigated the suppressive effects of blue light-emitting diode (LED) irradiation on bone resorption and changes in the oral microbiome of mice with ligature-induced periodontitis. Background: Wavelength of blue light has antimicrobial effects; however, whether blue LED irradiation alone inhibits the progression of periodontitis remains unclear. Methods: Nine-week-old male mice ligated ligature around the right maxillary second molar was divided into ligation alone (Li) and ligation with blue LED irradiation (LiBL) groups. The LiBL group underwent blue LED (wavelength, 455 nm) irradiation four times in a week at 150 mW/cm2 without a photosensitizer on the gingival tissue around the ligated tooth at a distance of 5 mm for 5 min. The total energy density per day was 45 J/cm2. Bone resorption was evaluated using micro-computed tomography at 8 days. Differences in the oral microbiome composition of the collected ligatures between the Li and LiBL groups were analyzed using next-generation sequencing based on the 16S rRNA gene from the ligatures. Results: Blue LED irradiation did not suppress bone resorption caused by ligature-induced periodontitis. However, in the LiBL group, the α-diversity, number of observed features, and Chao1 were significantly decreased. The relative abundances in phylum Myxococcota and Bacteroidota were underrepresented, and the genera Staphylococcus, Lactococcus, and Lactobacillus were significantly overrepresented by blue LED exposure. Metagenomic function prediction indicated an increase in the downregulated pathways related to microbial energy metabolism after irradiation. The co-occurrence network was altered to a simpler structure in the LiBL group, and the number of core genera decreased. Conclusions: Blue LED irradiation altered the composition and network of the oral microbiome of ligature-induced periodontitis in mice.

A Novel Injectable Piezoelectric Hydrogel for Periodontal Disease Treatment

Periodontal disease is a multifactorial, bacterially induced inflammatory condition characterized by the progressive destruction of periodontal tissues. The successful nonsurgical treatment of periodontitis requires multifunctional technologies offering antibacterial therapies and promotion of bone regeneration simultaneously. For the first time, in this study, an injectable piezoelectric hydrogel (PiezoGEL) was developed after combining gelatin methacryloyl (GelMA) with biocompatible piezoelectric fillers of barium titanate (BTO) that produce electrical charges when stimulated by biomechanical vibrations (e.g., mastication, movements). We harnessed the benefits of hydrogels (injectable, light curable, conforms to pocket spaces, biocompatible) with the bioactive effects of piezoelectric charges. A thorough biomaterial characterization confirmed piezoelectric fillers' successful integration with the hydrogel, photopolymerizability, injectability for clinical use, and electrical charge generation to enable bioactive effects (antibacterial and bone tissue regeneration). PiezoGEL showed significant reductions in pathogenic biofilm biomass (∼41%), metabolic activity (∼75%), and the number of viable cells (∼2-3 log) compared to hydrogels without BTO fillers in vitro. Molecular analysis related the antibacterial effects to be associated with reduced cell adhesion (downregulation of porP and fimA) and increased oxidative stress (upregulation of oxyR) genes. Moreover, PiezoGEL significantly enhanced bone marrow stem cell (BMSC) viability and osteogenic differentiation by upregulating RUNX2, COL1A1, and ALP. In vivo, PiezoGEL effectively reduced periodontal inflammation and increased bone tissue regeneration compared to control groups in a mice model. Findings from this study suggest PiezoGEL to be a promising and novel therapeutic candidate for the treatment of periodontal disease nonsurgically.

Lipocalin 2, synthesized using a cell-free protein synthesis system and encapsulated into liposomes, inhibits the adhesion of Porphyromonas gingivalis to human oral epithelial cells

BACKGROUND AND OBJECTIVE

Lipocalin 2 (LCN2), a glycoprotein expressed in epithelial cells and leukocytes, has an antibacterial effect and plays a role in innate immunity. The delivery of LCN2 encapsulated in liposomes to oral epithelium may be useful to prevent oral infectious diseases. This study aimed to investigate the inhibitory effect of LCN2, artificially synthesized using a cell-free protein synthesis (CFPS) system, on the adhesion of Porphyromonas gingivalis to oral epithelial cells in order to approach oral healthcare using LCN2.

METHODS

LCN 2 was synthesized using a CFPS system and assayed by Western blotting, mass spectrometry and enzyme-linked immunosorbent assay (ELISA). The bilayer liposomes were prepared by the spontaneous transfer method using 1,2-dioleoyl-sn-glycero-3 phosphocholine (DOPC), 3-sn-phosphatidylcholine from Egg Yolk (Egg-PC), and 1,2-dioleoyl-sn-glycero-3 phosphoethanolamine (DOPE). The cellular and medium fractions derived from the culture of oral epithelial cells with liposome-encapsulated LCN2 were assayed by Western blotting and ELISA. The effect of the synthesized LCN2 on adhesion of the labeled P. gingivalis to oral epithelial cells was investigated as an evaluation of its antibacterial activity.

RESULTS

The synthesized LCN2 protein was identified by Western blotting; its amino acid sequence was similar to that of recombinant LCN2 protein. The additions of DOPE and octa-arginine in the outer lipid-layer components of liposome significantly increased the delivery of liposomes to epithelial cells. When oral epithelial cells were cultured with the synthesized and liposome-encapsulated LCN2, LCN2 was identified in the cellular and medium fractions by Western blotting and its concentration in the cellular fraction from the culture with the synthesized LCN2 was significantly higher than that of a template DNA-free protein. The synthesized LCN2 and liposome-encapsulated LCN2 significantly inhibited the adhesion of P. gingivalis to oral epithelial cells compared with template DNA-free protein.

CONCLUSION

LCN2 was artificially synthesized by a CFPS system, encapsulated in liposomes, and delivered to oral epithelial cells, and demonstrated an antibacterial action against P. gingivalis. This approach may become a useful model for oral healthcare.

Role of ubiquitin-specific protease 5 in the inflammatory response of chronic periodontitis

BACKGROUND

The systemic inflammatory response caused by chronic periodontitis is a risk factor for multiple diseases. Ubiquitin-specific protease 5 (USP5) is a kind of deubiquitinase which mainly responsible for dissociating unanchored polyubiquitin. However, the functions of USP5 in chronic periodontitis have not been reported.

METHODS

Chronic periodontitis patients were recruited, and their periodontal samples were collected. The levels of USP5, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) in gingival crevicular fluid were evaluated by ELISA. The expression of USP5, TNF-α, IL-6, and IL-1β in human periodontal ligament stem cells (PDLSCs) was estimated by qRT-PCR assay. The activation of STAT3 signaling was examined by Western blot.

RESULTS

USP5 was upregulated in the gingival crevicular fluid and gingival tissues of chronic periodontitis patients. USP5 expression was positively correlated with the expression of proinflammatory factors. USP5 knockdown and deubiquitinase inhibitor inhibited LPS-induced inflammatory responses in PDLSCs. Suppressing USP5 inhibited STAT3 signaling in PDLSCs.

CONCLUSION

Suppression deubiquitinase USP5 inhibits the inflammatory response of chronic periodontitis by suppressing STAT3 signaling.

Nanomaterials: an intra-periodontal pocket drug-delivery system for periodontitis

Periodontitis is a microbiological condition that affects the tissues supporting the teeth. The fundamental to effective periodontal therapy is choosing the suitable antimicrobial and anti-inflammatory agent, together with the proper route of drug administration and delivery system. Intra-periodontal pocket approach with nano drug-delivery systems (NDDS) such as polymeric nanoparticles, gold nanoparticles, silica nanoparticles, magnetic nanoparticles, liposomes, polymersomes, exosomes, nano micelles, niosome, solid lipid nanoparticles, nano lipid carriers, nanocomposites, nanogels, nanofibers, scaffolds, dendrimers, quantum dots, etc., will be appropriate route of drug administration and delivery system. This NDDS delivers the drugs at the site of infection to inhibit growth and promote tissue regeneration. The present review focused on providing comprehensive information on the NDDS for periodontitis, which enhanced therapeutic outcomes via intra-periodontal pocket delivery.

Immunomodulatory Effect of Novel Electrospun Nanofibers Loaded with Doxycycline as an Adjuvant Treatment in Periodontitis

The immunomodulatory effect of a novel biomaterial obtained through electrospinning, based on polylactic acid (PLA) and nano-hydroxyapatite (nano-HAP), loaded with doxycycline (doxy) was evaluated in an animal model. The treatment capabilities as a local non-surgical treatment of periodontitis was investigated on the lower incisors of Wistar rats, after the induction of localized periodontitis using the ligature technique. Following the induction of the disease, the non-surgical treatment of scaling and root planing was applied, in conjunction with the application of the new material. The results of the treatment were evaluated clinically, using the tooth mobility and gingival index scores, as well as histologically. The salivary concentrations of matrix metalloproteinase 8 (MMP-8) and plasmatic concentrations of interleukin 1 (IL-1), interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) were also monitored. Two weeks after the ligature application, the periodontal disease was successfully induced in rats. The application of the novel biomaterial obtained through electrospinning was proven to be more effective in improving the clinical parameters, while decreasing the salivary MMP-8 and plasmatic IL-1 and TNF-α concentrations, compared to the simple scaling and root planing. Thus, the novel electrospun biomaterial could be a strong candidate as an adjuvant to the non-surgical periodontal therapy.

A Placebo-Controlled Trial to Evaluate Two Locally Delivered Antibiotic Gels (Piperacillin Plus Tazobactam vs. Doxycycline) in Stage III-IV Periodontitis Patients

Background and objectives: this study aims to evaluate the clinical and microbiological effects of a single subgingival administration of a locally delivered antibiotic gel containing piperacillin plus tazobactam and compare it with a slow-release doxycycline (14%) gel and a placebo gel, following subgingival instrumentation (SI) in patients with severe periodontitis. Materials and methods: sixty-four patients diagnosed with stage III-IV periodontitis were enrolled, were randomly assigned into three groups, and were treated additionally with a single subgingival administration of piperacillin plus tazobactam gel (group A); doxycycline gel (group B); and placebo gel (group C). The primary outcome variable was the change in mean probing pocket depth (PPD) 6 months after the intervention. Secondary outcome variables were changes in mean full-mouth bleeding score (FMBS); full-mouth plaque score (FMPS); overall bleeding index (BOP); pocket closure; and clinical attachment level (CAL), along with changes in the numbers of five keystone bacteria: Aggregatibacter actinomycetemcomitans (A.a.), Porphyromonas gingivalis (P.g.), Prevotella intermedia (P.i.), Tannerella forsythia (T.f.), and Treponema denticola (T.d.). Intergroup and intragroup differences were evaluated at 3 and 6 months. Results: at baseline, the three groups were comparable. An improvement in clinical parameters such as PPD, CAL, and BOP between groups was observed at 3 and 6 months, but without statistical significance (p > 0.05). At 6 months, the intragroup analysis showed a significant reduction in clinical parameters. Even though the piperacillin plus tazobactam group showed slightly higher PPD reduction, this was not statistically significant when compared to both control groups. Conclusions: The groups had similar results, and subgingival instrumentation can be executed without adjunctive antimicrobials, reducing the costs for the patient and the working time/load of the professional.

The effects of adjunctive use of a desiccant agent in the treatment of stage III periodontitis (Randomized controlled clinical trial)

Introduction

Several bacterial species inhabiting the dental plaque biofilms are associated with periodontitis.

Objective

The main objective of this study was to compare the efficacy of the desiccant agent HYBENX (HBX) as an adjunct to scaling and root planning (SRPX) versus scaling and root planning (SRP) alone in the treatment of periodontitis.

Materials and Methods

The study sample comprised 25 patients with periodontitis stage Ш (grades A and B). Each maxillary quadrant was randomly allocated to two groups: SRPX group, including 25 quadrants treated with SRP plus HYBENX, and SRP group, including 25 quadrants treated with SRP alone. The following clinical periodontal parameters were recorded at baseline (immediately after treatment, T0), and 1 month (T1), 3 months (T3), and 6 months (T6) after treatment: probing pocket depth (PPD), relative attachment level (RAL), plaque index (PLI), gingival index (GI), gingival height (GH), and bleeding on probing index (BOP).

Results

Comparisons within each study group showed that all clinical parameters significantly improved (P < 0.001) at all follow-up intervals. In contrast, a statistically significant difference (P < 0.001) was observed in RAL, PPD, BOP, and GI indices at all follow-up intervals between the SRPX and SRP groups. In contrast, no significant differences (P > 0.05) were found in GH and PLI between the study groups.

Conclusion

Both treatment groups showed improved periodontal parameters. However, applying desiccant gel as an adjunct to SRP was significantly effective in the treatment of stage III periodontitis.

Systemic antibiotics increase microbiota pathogenicity and oral bone loss

Periodontitis is the most widespread oral disease and is closely related to the oral microbiota. The oral microbiota is adversely affected by some pharmacologic treatments. Systemic antibiotics are widely used for infectious diseases but can lead to gut dysbiosis, causing negative effects on the human body. Whether systemic antibiotic-induced gut dysbiosis can affect the oral microbiota or even periodontitis has not yet been addressed. In this research, mice were exposed to drinking water containing a cocktail of four antibiotics to explore how systemic antibiotics affect microbiota pathogenicity and oral bone loss. The results demonstrated, for the first time, that gut dysbiosis caused by long-term use of antibiotics can disturb the oral microbiota and aggravate periodontitis. Moreover, the expression of cytokines related to Th17 was increased while transcription factors and cytokines related to Treg were decreased in the periodontal tissue. Fecal microbiota transplantation with normal mice feces restored the gut microbiota and barrier, decreased the pathogenicity of the oral microbiota, reversed the Th17/Treg imbalance in periodontal tissue, and alleviated alveolar bone loss. This study highlights the potential adverse effects of long-term systemic antibiotics-induced gut dysbiosis on the oral microbiota and periodontitis. A Th17/Treg imbalance might be related to this relationship. Importantly, these results reveal that the periodontal condition of patients should be assessed regularly when using systemic antibiotics in clinical practice.

Near-Infrared-Enhanced Dual Enzyme-Mimicking Ag-TiO2-x@Alginate Microspheres with Antibactericidal and Oxygeneration Abilities to Treat Periodontitis

The effective treatment for periodontitis is to completely and sustainedly eradicate the bacterial pathogens from the complex periodontal pockets. Local sustained-release antibiotics as a complementary treatment after scaling and root planning can sustainedly combat bacterial pathogens in the periodontal pockets to help treat the disease, but the increasing concern of bacterial resistance limits its future use. Here, we reported a local antibacterial system based on microsized multifunctional Ag-TiO_2-x encapsulated in alginate (ATA) microspheres. We confirmed that ATA displayed strong photothermally enhanced dual enzyme-mimicking (peroxidase-like and catalase-like) activities and weak photocatalytic activity under 808 nm near-infrared (NIR) irradiation, which could boost the generation of reactive oxygen species (ROS) and O₂ in the presence of low-level H₂O₂. As a result, the ATA/H₂O₂/NIR system exhibited efficient antibacterial activity against Porphyromonas gingivalis and Streptococcus gordonii in both planktonic and biofilm forms. With the help of ROS, ATA could release Ag⁺ in concentrations sufficient to inhibit periodontal pathogens as well. Moreover, the in situ-generated oxygen was supposed to alleviate the local hypoxic environment and would help downregulate the lipopolysaccharide-mediated inflammatory response of periodontal stem cells. The in vivo rat periodontitis treatment results demonstrated that the ATA/H₂O₂/NIR system reduced the bacterial load, relieved inflammation, and improved tissue healing. Our work developed a new local prolonged bactericidal and oxygenation system for enhanced periodontitis. Avoiding the usage of antibiotics and nanomaterials, this strategy showed great promise in adjunctive periodontitis treatment and also in other biomedical applications.

Coaxial electrospun nanofibers as drug delivery system for local treatment of periodontitis

OBJECTIVES

The aim of the present study was to prepare resorbable polylactide fibers for periodontitis treatment using coaxial electrospinning to optimize the release of metronidazole (MNA) by reducing the initial burst effect.

METHODS

Poly(L-lactide-co-D,L-lactide) (PLA) fibers mats with different distributions of metronidazole (MNA) were manufactured by coaxial electrospinning (COAX). By COAX spinning the central core of the fiber was enriched with 40% MNA (m/m), while the sheath of the fiber consisted of PLA only (test group). In contrast, fibers of the control group were prepared by conventional electrospinning with the same amount of MNA but with a homogenous drug distribution (HDD - homogenously distributed drug). The release of MNA was determined by analyzing aliquots from the fiber mats using UV-VIS spectroscopy. Agar diffusion tests were carried out to determine the antibacterial effect on periodontopathogenic bacteria. Biocompatibility was tested in direct contact to human gingival fibroblasts (HGF) for two days.

RESULTS

The COAX mats showed a retarded drug release compared to the conventional HDD fibers. After 24 h, 64% of total MNA was released cumulatively from the COAX fibers while 90% of the MNA was released from the HDD fibers (controls). The antibacterial effect of COAX fibers was significantly higher after 24 h compared to the HDD fibers. Cell cultivation revealed significant higher numbers of vital cells among the COAX mats.

SIGNIFICANCE

COAX fibers showed improved sustained MNA release compared to conventional fibers and can be seen as potential drug delivery systems in local periodontitis treatment.

Systemic Antibiotics as an Adjunct to Subgingival Debridement: A Network Meta-Analysis

This review aimed to evaluate the effectiveness of systemic antibiotics as adjunctive treatment to subgingival debridement in patients with periodontitis. Randomized controlled trials were included that assessed the effectiveness of systemic antibiotics in improving periodontal status, indicated by clinical attachment gain level, probable pocket depth reduction, and bleeding on probing reduction of patients with any form of periodontitis at any follow-up time. Network meta-analyses with a frequentist model using random effects was employed to synthesize the data. The relative effects were reported as mean difference with a 95% confidence interval. Subsequently, all treatments were ranked based on their P-scores. A total of 30 randomized controlled trials were included in this network meta-analyses. Minimally important clinical differences were observed following the adjunctive use of satranidazole, metronidazole, and clindamycin for clinical attachment gain level and probable pocket depth reduction. For bleeding on probing reduction, minimally important clinical differences were observed following the adjunctive use of metronidazole and a combination of amoxycillin and metronidazole. However, the network estimates were supported by evidence with certainty ranging from very low to high. Therefore, the findings of this network meta-analyses should be interpreted with caution. Moreover, the use of these antibiotics adjunct to subgingival debridement should be weighed against possible harm to avoid overuse and inappropriate use of these antibiotics in patients with periodontitis.

Antibiofilm activity of ultra-small gold nanoclusters against Fusobacterium nucleatum in dental plaque biofilms

Pathogenic dental plaque biofilms are universal and harmful, which can result in oral infections and systemic diseases. Many conventional therapeutic methods have proven insufficient or ineffective against plaque biofilms. Therefore, new strategies are urgently needed. Fusobacterium nucleatum (F. nucleatum), a periodontal pathogen associated with a variety of oral and systemic diseases, is thought to be central to the development and structure of dental plaques. Here, ultra-small gold nanoclusters (AuNCs) were prepared. They exhibited potent antibacterial activity against F. nucleatum through enhanced destruction of bacterial membranes and generation of reactive oxygen species. Furthermore, due to their excellent penetration, the AuNCs could inhibit biofilm formation and destroy mature biofilms in vitro. Their antibiofilm efficacy was further confirmed in a mouse model, where they reduced biofilm accumulation and ameliorated inflammation. Meanwhile, the disruption of oral and gut microbiota caused by colonization of oral F. nucleatum could be partially restored through AuNCs treatment. Therefore, AuNCs could be considered as promising antibiofilm agents and have great potential in the clinical treatment of dental plaque.

Thermoresponsive Azithromycin-Loaded Niosome Gel Based on Poloxamer 407 and Hyaluronic Interactions for Periodontitis Treatment

Azithromycin (AZM) is a potential antimicrobial drug for periodontitis treatment. However, a potential sustained-release system is needed for intra-periodontal pocket delivery. This study focused on the development and evaluation of a thermoresponsive azithromycin-loaded niosome gel (AZG) to search for a desirable formulation for periodontitis treatment. AZG was further developed from an AZM-loaded niosomal formulation by exploiting the advantages of poloxamer 407 (P407) and hyaluronic acid (HA) interactions. The results showed that the addition of HA decreased the gelation temperature and gelation time of AZG. HA was found to increase the viscosity as well as mucoadhesive and tooth-root surface adhesive properties. The AZG solution state was injectable and exhibited pseudoplastic shear-thinning behavior. P407–HA interactions in AZG could contribute to gel strength. AZG showed 72 h of continuous drug release following the Korsmeyer–Peppas model and potentially enhanced drug permeation. The formulations apparently presented more efficient antibacterial activity against major periodontal pathogens than the standard AZM solution. AZM intra-periodontal pocket formulation and the remarkable properties of niosomes exhibited potential characteristics, including ease of administration, bioadhesion to the anatomical structure of the periodontal pocket, and sustained drug release with competent antimicrobial activity, which could be beneficial for periodontitis treatment.

In Vitro Antimicrobial Effect of Novel Electrospun Polylactic Acid/Hydroxyapatite Nanofibres Loaded with Doxycycline

The present study aimed to assess the in vitro antimicrobial effects of a novel biomaterial containing polylactic acid (PLA), nano-hydroxyapatite (nano-HAP) and Doxycycline (Doxy) obtained by electrospinning and designed for the non-surgical periodontal treatment. The antimicrobial activity of two samples (test sample, PLA-HAP-Doxy7: 5% PLA, nano-HAP, 7% Doxy and control sample, PLA-HAP: 5% PLA, nano-HAP) against two periodontal pathogens—Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis—was assessed using the Kirby−Bauer Disk Diffusion Susceptibility Test and compared with the effect of four antibiotics used as adjuvants in periodontal therapy: Amoxicillin, Ampicillin, Doxy and Metronidazole. The test sample (embedded with Doxy) showed higher inhibitory effects than commonly used antibiotics used in the treatment of periodontitis, while the control sample showed no inhibitory effects. Moreover, significant differences were observed between the inhibition zones of the two samples (p < 0.05). The Doxy-loaded PLA nanofibres had an antimicrobial effect against the periodontal pathogens. Based on these results, the novel biomaterial could be a promising candidate as adjuvant for the non-surgical local treatment in periodontitis.