Ultraviolet Radiation Effect on Rats Tooth Root Dentin Structure Under Experimental Endodontic Treatment

The aim of the study is to investigate the effect of ultraviolet radiation with a wavelength of (255 ± 5) nm on the dentin structure of the root canal of rat teeth. Objectives: to identify the level of treatment of the orifice third of the root canal using an electron scan of the tooth cross-section, the morphological structure of its walls and the degree of obturation of the dentinal tubules with detritus; to identify the level of treatment of the middle third of the root canal using an electron scan of the tooth cross-section, the morphological structure of its walls and the degree of obturation of the dentinal tubules with detritus; to assess the level of treatment of the apical third of the tooth root using an electron scan of the tooth cross-section, the morphological structure of its walls and the degree of obturation of the dentinal tubules with detritus. During the experimental study, the effect of ultraviolet radiation ((255 ± 5) nm) on the dentin structure of the root canals in laboratory rats was analyzed. The morphological evaluation included an analysis of the histoarchitecture of root dentin, detection of organic inclusions within the canal lumen, qualitative treatment characteristics, and wall surface topography. The study was conducted on 45 mature CD individuals, divided into three equal groups, using first lower molars (two teeth from each individual). Comparative electron microscopic analysis of root sections revealed superior cleaning efficiency of the root canal system when using additional physical factors – a diode laser (980 nm) and ultraviolet radiation (255 ± 5 nm) – in both the lumen and parietal aspects. These techniques ensure optimal removal of the smear layer while maintaining the structural integrity of the root dentin.