Influence of the Ratio of Antibacterial and Anti-Inflammatory Components on the Effectiveness of Gels in Correcting Gingival Microcirculation Disorders in Animals with Experimental Periodontitis

Introduction. Microcirculation disorders accompanying the inflammatory response to periodontopathogenic microflora are a key element in the pathogenesis of periodontitis. The complex therapy of periodontitis includes the administration of antibacterial and anti-inflammatory drugs, which can be optimized through modern microencapsulation technologies that allow creating dosage forms combining different classes of drugs. In this regard, optimization of the ratio of antibacterial and antiinflammatory agents in multi-target drugs is of not only scientific but also practical interest. The aim of the study was to investigate the effect of a range of experimental gel samples with different ratios of microcapsules containing anti-inflammatory and antibacterial substances on the state of the gingival microcirculatory bed in animals with experimental periodontitis. Materials and methods. The studies were carried out on 50 white rats. The experimental design involved dividing all animals into several groups: control (rats with intact gingiva); comparison group (animals with experimental periodontitis); experimental groups № 1, № 2, № 3 (rats with experimental periodontitis treated with a gel containing microcapsules with AgNPs loaded with an equal ratio of tannic acid and metronidazole (1:1), a predominance of capsules with tannic acid (2:1) and a predominance of metronidazole capsules (1:2), respectively). Periodontitis was modeled using the ligature method by suturing a polyfilament non-absorbable thread into the gums in the area of the lower jaw incisors. The state of the microcirculation in all presented groups was assessed using laser Doppler flowmetry after removal of the ligature on the 21st day of the experiment. Results. It has been established that gel applications containing an equal amount of active substances effectively reduce the increased perfusion rate by 30% and partially correct the parameters of active and passive blood flow modulation in rats with experimental periodontitis. A gel with a predominance of antibacterial components reduces the perfusion index by 23%, but does not ensure the restoration of active and passive modulation of gingival blood flow in white rats with experimental periodontitis. The use of the gel, in which the anti-inflammatory component predominates ensures complete restoration of gingival microcirculation in animals with periodontitis. The gel with a predominance of anti-inflammatory components exceeds the analogue with an equal ratio of capsules with active substances in the correction of cardiac oscillations by 39%, as well as the analogue with a predominance of antibacterial components in the effectiveness of perfusion correction by 4%, myogenic by 38%, neurogenic by 27%, respiratory by 1.3 times and cardiac oscillations by 1.4 times. Conclusions. Gels containing microcapsules with tannic acid and metronidazole significantly correct gingival perfusion disorders and its modulation mechanisms in rats with experimental periodontitis. The efficiency of correction of microcirculatory disorders in animals with periodontitis depends on the ratio of antibacterial and anti-inflammatory components in the gel. The use of a gel sample containing capsules with tannic acid and metronidazole in a ratio of 2:1 in rats with experimental periodontitis ensures complete restoration of gingival microcirculation.