In vitro characterization of injectable chlorhexidine‐eluting gelatin hydrogels for local treatment of periodontal infections

Abstract

Infection of the periodontal pocket presents two major challenges for drug delivery: administration into the periodontal pocket and a high fluid clearance rate in the pocket. The current study aimed to develop and study a novel gelatin-based hydrogel system crosslinked using a carbodiimide, for delivery of chlorhexidine (CHX) directly into the periodontal pocket via injection followed by in situ gelation.The study focused on the effects of the CHX concentration on its release profile and on the hydrogel's physical, mechanical, and biological properties. CHX is a common antiseptic agent and is considered as "gold standard" in dental practice.Its release profile demonstrated 39% burst release during the initial 2 h, followed by a release rate, which decreases with time for 6 days. A mathematical model based on the two-stage desorption theory was perfectly fitted to the experimental release profiles (R 2 > 0.99). Fibroblast viability results of at least 70% were achieved after 24 and 48 h, indicating that the system is biocompatible. The nonloaded and CHX-loaded hydrogels were found suitable for injectability and exhibited desired gelation times of 7.5-10.6 s, that is, compatible for filling a periodontal pocket. They exhibited excellent mechanical properties, such as burst strength (sealing ability) of 233-357 mmHg, tensile modulus of 47-69 kPa, compressive modulus of 58-104 kPa, and tensile strain of 42-113%. In conclusion, the studied CHX eluting hydrogels are of high potential to be used in minor pockets as well as deep pockets and are expected to be suitable for successfully treating a wide range of periodontal infections.

Thermosensitive acetylated carboxymethyl chitosan gel depot systems sustained release caffeic acid phenethyl ester for periodontitis treatment

“…In the present study, CCK‐8 assay was used to evaluate the cytotoxicity of free CAPE and the selected A‐CC samples (A‐CC 3). Briefly, Weigh 50 mg of freeze‐dried CAPE‐A‐CC 3 gels, finely grind it and disperse it in 5 ml PBS, Then the A‐CC 3 gel and CAPE‐A‐CC 3 gels were mixed with Dulbecco's Modified Eagle's medium (DMEM) to prepare concentrations of 2.5, 5, 10, and 20 μM 33 . RAW 264.7 cells (1 × 10 4 cells/well) and hPDLSC cells (1 × 10 4 cells/well) were seeded in 96‐well plate in DMEM medium comprising 10% fetal bovine serum (FBS) and 1% penicillin and streptomycin (PS), and incubated at 37°C with 5% CO 2 for 24 h. Then, the CCK‐8 solution (150 μl) was added to each well, and the samples were incubated for 2 h at 37°C.…”

“…Briefly, Weigh 50 mg of freeze-dried CAPE-A-CC 3 gels, finely grind it and disperse it in 5 ml PBS, Then the A-CC 3 gel and CAPE-A-CC 3 gels were mixed with Dulbecco's Modified Eagle's medium (DMEM) to prepare concentrations of 2.5, 5, 10, and 20 μM. 33…”

Recent advances in injectable hydrogel therapies for periodontitis

“…Natural polymer materials include chitosan (CS), 36 gelatin, sodium alginate, hyaluronic acid (HA), 30 and collagen. 36,37 The majority of these polymers have water-soluble surfaces that encourage cell adhesion, growth, and differentiation. They also show low cost, superior biocompatibility, and biodegradability, but weak mechanical strength and bad stability are their primary disadvantages.…”