Enhanced immunomodulation and periodontal regeneration efficacy of subgingivally delivered progranulin-loaded hydrogel as an adjunct to non-surgical treatment for Class II furcation involvement in dogs

AIM

To evaluate the effect of subgingival delivery of progranulin (PGRN)/gelatin methacryloyl (GelMA) complex as an adjunct to scaling and root planing (SRP) on an experimental periodontitis dog model with Class II furcation involvement (FI).

MATERIALS AND METHODS

A Class II FI model was established, and the defects were divided into four treatment groups: (a) no treatment (control); (b) SRP; (c) SRP + GelMA; (d) SRP + PGRN/GelMA. Eight weeks after treatment, periodontal parameters were recorded, gingival crevicular fluid and gingival tissue were collected for ELISA and RT-qPCR, respectively, and mandibular tissue blocks were collected for micro computed tomography (micro-CT) scanning and hematoxylin and eosin (H&E) staining.

RESULTS

The SRP + PGRN/GelMA group showed significant improvement in all periodontal parameters compared with those in the other groups. The expression of markers related to M1 macrophage and Th17 cell significantly decreased, and the expression of markers related to M2 macrophage and Treg cell significantly increased in the SRP + PGRN/GelMA group compared with those in the other groups. The volume, quality and area of new bone and the length of new cementum in the root furcation defects of the PGRN/GelMA group were significantly increased compared to those in the other groups.

CONCLUSIONS

Subgingival delivery of the PGRN/GelMA complex could be a promising non-surgical adjunctive therapy for anti-inflammation, immunomodulation and periodontal regeneration.

Multifunctional hybrid hydrogel for the prevention of post-surgery tumor recurrence

In this study, we present a multifunctional hybrid hydrogel (MFHH) for the prevention of postoperative tumor recurrence. MFHH consists of two components; component A - containing a gelatin-based cisplatin, which destroys the residual cancer after surgery, and component B - containing macroporous gelatin microcarriers (CultiSpher) loaded with freeze-dried bone marrow stem cells (BMSCs), which activates the wound healing process. We also evaluated the effects of MFHH in a subcutaneous Ehrlich tumor mouse model. MFHH acted as a local delivery system by directly supplying cisplatin to the tumor environment, resulting in excellent anti-cancer effects and minimal side effects. MFHH released cisplatin gradually to destroy the residual tumors, thereby preventing loco-regional recurrence. We have also demonstrated that BMSCs are able to inhibit residual tumor growth. Moreover, CultiSpher loaded with BMSCs acted as an injection 3D scaffold and easily filled the wound defect formed by tumor removal, and the paracrine factors of the freeze-dried BMSCs accelerated the wound healing process. The components of the MFHH can be used both separately and together. However, for the successful application of MFHH in clinical practice, it is necessary to study in more detail the role of paracrine factors of freeze-dried BMSCs in the inhibition or proliferation of residual cancer. These questions will be the focus of our future research.

Establishment of a Rodent Glioblastoma Partial Resection Model for Chemotherapy by Local Drug Carriers-Sharing Experience

Local drug delivery systems (LDDS) represent a promising therapy strategy concerning the most common and malignant primary brain tumor glioblastoma (GBM). Nevertheless, to date, only a few systems have been clinically applied, and their success is very limited. Still, numerous new LDDS approaches are currently being developed. Here, (partial resection) GBM animal models play a key role, as such models are needed to evaluate the therapy prior to any human application. However, such models are complex to establish, and only a few reports detail the process. Here, we report our results of establishing a partial resection glioma model in rats suitable for evaluating LDDS. C6-bearing Wistar rats and U87MG-spheroids- and patient-derived glioma stem-like cells-bearing athymic rats underwent tumor resection followed by the implantation of an exemplary LDDS. Inoculation, tumor growth, residual tumor tissue, and GBM recurrence were reliably imaged using high-resolution Magnetic Resonance Imaging. The release from an exemplary LDDS was verified in vitro and in vivo using Fluorescence Molecular Tomography. The presented GBM partial resection model appears to be well suited to determine the efficiency of LDDS. By sharing our expertise, we intend to provide a powerful tool for the future testing of these very promising systems, paving their way into clinical application.

Current research progress of local drug delivery systems based on biodegradable polymers in treating chronic osteomyelitis

Chronic osteomyelitis is one of the most challenging diseases in orthopedic treatment. It is usually treated with intravenous antibiotics and debridement in clinical practice, which also brings systemic drug side effects and bone defects. The local drug delivery system of antibiotics has the characteristics of targeted slow release to the lesion site, replacing systemic antibiotics and reducing the toxic and side effects of drugs. It can also increase the local drug concentration, achieve sound bacteriostatic effects, and promote bone healing and formation. Currently, PMMA beads are used in treating chronic osteomyelitis at home and abroad, but the chain beads need to be removed after a second operation, inconveniences patients. Biodegradable materials have been extensively studied as optimal options for antibiotic encapsulation and delivery, bringing new hope for treating chronic osteomyelitis. This article reviews the research progress of local drug delivery systems based on biodegradable polymers, including natural and synthetic ones, in treating chronic osteomyelitis.

Synthesis and Characterization of New Biodegradable Injectable Thermosensitive Smart Hydrogels for 5-Fluorouracil Delivery

In this paper, injectable, thermosensitive smart hydrogel local drug delivery systems (LDDSs) releasing the model antitumour drug 5-fluorouracil (5-FU) were developed. The systems were based on biodegradable triblock copolymers synthesized via ring opening polymerization (ROP) of ε-caprolactone (CL) in the presence of poly(ethylene glycol) (PEG) and zirconium(IV) acetylacetonate (Zr(acac)₄), as co-initiator and catalyst, respectively. The structure, molecular weight (M_n) and molecular weight distribution (Đ) of the synthesized materials was studied in detail using nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC) techniques; the optimal synthesis conditions were determined. The structure corresponded well to the theoretical assumptions. The produced hydrogels demonstrated a sharp sol–gel transition at temperature close to physiological value, forming a stable gel with good mechanical properties at 37 °C. The kinetics and mechanism of in vitro 5-FU release were characterized by zero order, first order, Higuchi and Korsmeyer–Peppas mathematical models. The obtained results indicate good release control; the kinetics were generally defined as first order according to the predominant diffusion mechanism; and the total drug release time was approximately 12 h. The copolymers were considered to be biodegradable and non-toxic; the resulting hydrogels appear to be promising as short-term LDDSs, potentially useful in antitumor therapy.

Polymeric Carriers for Delivery Systems in the Treatment of Chronic Periodontal Disease

Periodontitis (PD) is a chronic inflammatory disease of periodontal tissues caused by pathogenic microorganisms and characterized by disruption of the tooth-supporting structures. Conventional drug administration pathways in periodontal disease treatment have many drawbacks such as poor biodistribution, low selectivity of the therapeutic effect, burst release of the drug, and damage to healthy cells. To overcome this limitation, controlled drug delivery systems have been developed as a potential method to address oral infectious disease ailments. The use of drug delivery devices proves to be an excellent auxiliary method in improving the quality and effectiveness in periodontitis treatment, which includes inaccessible periodontal pockets. This review explores the current state of knowledge regarding the applications of various polymer-based delivery systems such as hydrogels, liposomes, micro-, and nanoparticles in the treatment of chronic periodontal disease. Furthermore, to present a more comprehensive understanding of the difficulties concerning the treatment of PD, a brief description of the mechanism and development of the disease is outlined.

Efficacy of xanthan based chlorhexidine gel as an adjunct to scaling and root planing in treatment of the chronic periodontitis

Aim:

The aim of this study was to evaluate the clinical effectiveness of locally delivered xanthan-based Chlosite^® gel as an adjunctive therapy to scaling and root planing in treatment of chronic periodontitis.

Materials and Methods:

In a randomized controlled clinical study, 30 patients were selected. Pocket depth between 5 and 7 mm was selected and each patient had two sites on the same side of the mouth. A total of 30 control sites were scaled and root planed and 30 test sites were scaled and root planed and Chlosite^® gel was added. The clinical parameters, probing depth (PD), clinical attachment level (CAL), plaque index (PI) and bleeding on probing (BOP), gingival index were recorded at baseline, 6 weeks, 3 months and 6 months.

Statistical Analysis:

Paired/unpaired t-test was used, significance was placed at 5% level of significance, i.e., P < 0.05 was considered as a significant.

Results:

From baseline to a period of 6 months, significant difference was found between test and control group for PD, CAL, PI and BOP, P value being PD (P = 0.002), CAL index (P = 0.014), respectively.

Conclusion:

Subgingival injection of xanthan-based Chlosite^® gel adjunct with scaling and root planing appeared to cause significant improvement compared with scaling and root planing alone in persons with chronic periodontitis.

To assess the effectiveness of a chlorhexidine chip in the treatment of chronic periodontitis: A clinical and radiographic study

CONTEXT

Controlled local delivery of disinfecting agents has been demonstrated to be efficient in improving the outcome of periodontal therapy.

AIMS

The aim of the present study was to evaluate the efficacy of a controlled-release biodegradable chlorhexidine chip (Periocol CG) when used as an adjunct to scaling and root planing in the treatment of periodontitis.

SETTINGS AND DESIGN

The study was carried out as randomized controlled two-group parallel clinical trial.

MATERIALS AND METHODS

Forty patients in the age group of 30-65 years suffering from mild to moderate chronic periodontitis, having pocket depth ranging between 5 and 8 mm, were selected for the study. At the screening visit, complete history taking, periodontal examination and full-mouth supragingival scaling was carried out for each patient. At the baseline visit (on the 7(th) day), all clinical parameters and radiographic parameters were recorded at selected sites and patients were randomly assigned to either the control group (group A) or the treatment group (group B). All patients in both the groups received complete subgingival scaling and root planing. Then, in group B, chlorhexidine chip (Periocol CG) was inserted at the selected site. Patients were recalled at 1 month, 2 months and 3 months from the baseline for recording clinical observations, and radiographic parameters were recorded at the end of the study.

STATISTICAL ANALYSIS

Mean, standard deviation, Chi-square test, "t" test for equality of means and paired samples correlations were used.

RESULTS

There was a statistically significant clinical attachment gain, reduction in bleeding index scores, probing pocket depth reduction and bone gain in both the groups, but group B showed better results than group A, and these differences were statistically significant.

CONCLUSIONS

The results of this study show that chlorhexidine chip (PerioCol-CG) is an effective adjunctive therapy to scaling and root planing in the treatment of chronic periodontitis.

Effect of a controlled release device containing minocycline microspheres on the treatment of chronic periodontitis: A comparative study

INTRODUCTION

Adjunctive therapy with locally delivered antimicrobials has resulted in improved clinical outcomes. The aim of this study was to evaluate the efficacy and safety of locally administered minocycline microspheres (Arestin) in the treatment of chronic periodontitis.

MATERIALS AND METHODS

A total of 60 sites from 15 patients in the age group of 35-50 years, who had periodontal pockets measuring 5-8 mm and had been diagnosed with chronic periodontitis, were selected for the study. The selected groups were randomly assigned to either the control group (group A) or the treatment/test group (group B). Only scaling and root planing were done at the base line visit for the control sites followed by local application of Arestin (1 mg). Clinical parameters such as plaque index, gingival index, and gingival bleeding index were recorded at baseline, day 30, day 90, and day 180 in the selected sites of both the groups. Probing pocket depth also was recorded at baseline, day 90, and day 180 for both the groups.

RESULTS

A statistically significant reduction was observed in both groups. Group B showed better results than Group A and these differences were statistically significant.

CONCLUSION

The results of this study clearly indicate that treatment with scaling and root planing plus minocycline microspheres (Arestin) is more effective and safer than scaling and root planing alone in reducing the signs of chronic periodontitis.