Examination of the Microvasculature During Wound Process of the Oral Mucosa when Using Dual-Wavelength Photodynamic Therapy: a Pre-Clinical Experimental Randomized Study

Abstract

Background. Healing of open wounds in the oral cavity is often accompanied by infection and constant traumatization, which lead to impaired blood supply to the tissues, lack of trophic support and low oxygen supply to increasing proliferative processes. Recently, photodynamic therapy has taken its place among the methods for stimulating regeneration of oral mucosal tissues. The authors consider it essential to study the influence of photodynamic treatment on the functional state of the microvasculature in the wound tissues, which determines the transcapillary exchange and the tissue respiration, providing the tissue regeneration.Objective. To study the photodynamic effect of sequential dual-wavelength radiation on the microvasculature in the wound tissues of the oral mucosa in vivo.Methods. The study was carried out on 36 female outbred Wistar rats, weighing 200–250 g. The animals were divided into two groups: control group (n = 18) and experimental group (n = 18). Wound surfaces healed by secondary intention were modeled on the cheek mucosa of the animals. Dual-wavelength photodynamic therapy was performed in the 1st postoperative day in experimental group. The microcirculatory function was assessed by Doppler flowmetry before, and on days 3, 7 and 14 after wounding. The results were processed using IBM SPSS Statistics 26.0.0.1 (IBM Inc., USA).Results. It has been established that dual-wavelength photodynamic therapy has a positive effect on the restoration of the microvasculature of the wound tissues. This therapy facilitated bypassing for microcirculatory flow on the 3rd day of the study, and increased the perfusion of tissues on the 7th. The experimental group did not have congestive-ischaemic phenomena in the wound region; the microcirculatory flow was augmented through the microcirculation regulation by the 14th day.Conclusion. Following the obtained results the use of dual-wavelength photodynamic therapy can be considered as a promising method for restoration of the microvasculature of tissues in the oral mucosal trauma.

Keywords

• photodynamic therapy
• wound process
• oral mucosa
• microvasculature
• laser doppler flowmetry