The relevance of studies on the thermal stability of fiber Bragg gratings arises from the prospects of their applications in difficult operating conditions at elevated temperatures. One of the highest-temperature types of such structures formed in silica glass fibers are regenerated Bragg gratings. Generally, the regeneration effect is observed in gratings inscribed in molecular hydrogen-loaded fibers and/or in highly-doped germanosilicate fibers. This paper describes the first reported regeneration of gratings created via point-by-point inscription with femtosecond laser radiation in standard telecommunication fiber Corning SMF-28 without the presence of hydrogen in technological processes. The paper proposes an explanation of the possible mechanism for the formation of such regenerated structures.