Identification of a person by papillary patterns is one of the key methods in forensic and criminalistic practice due to the uniqueness and stability of papillary patterns, which do not change during life under the influence of external factors. However, after death, especially with prolonged exposure to the external environment, soft tissues undergo putrefactive changes, mummification or other postmortem transformations, which significantly complicates or makes impossible the procedure of fingerprint identification. Purpose of the study. To analyze and create modern methods for restoring papillary patterns on the fingers of putrefactively changed and mummified corpses, in particular chemical, mechanical and digital technologies. Materials and methods. During the forensic examination of a corpse in a state of late cadaveric changes in the form of mummification and skeletonization, both hands of the corpse were cut off at the level of the radiocarpal joints. After that, the 2nd and 4th fingers of the left hand were cut off at the level of the interphalangeal joints. The 2nd finger of the left hand was placed in Ratnevsky's solution No. 2; the 4th finger of the left hand was placed in the MF24 solution. After the fingers were in the corresponding solutions, they were removed, examined under a trinocular stereomicroscope "RF4-6565pro" and fingerprints were obtained using the classical method. Research results. It was found that after 5 days of exposure to Ratnevsky's solution No. 2, the mummified 2nd finger of the left hand regained its volume, most of the folds straightened, the epidermis completely exfoliated, and the dermis acquired a pale yellow color. To straighten the remaining folds, the finger was pricked with a 50% aqueous solution of glycerin according to the Swenson and Wendel method. During stereomicroscopic examination, the papillary pattern is poorly distinguished due to the flattening of its ridges and furrows. At the same time, the resulting print has poor clarity, low contrast, and there is partially no clear contact in several areas. After 12 hours in the MF24 solution, the mummified 4th finger of the left hand significantly recovered its volume, the soft tissues regained their natural elasticity and firmness, the epidermis was completely exfoliated, the dermis became pale brown, and the residual folds were easily straightened. The resulting print looks structured with clearly visible details, and the mutual arrangement of the details of the pattern structure is preserved over the entire area of the print. An algorithm for restoring mummified fingers of the hands has been developed for further dactyloscopy and comparative research. When comparing the results of the exposure of the severed first, second and fourth fingers of the left hand in the above-described solutions, the soap solution proved to be unsuitable in the conditions of the need for prompt identification of the bodies of servicemen due to the required long exposure time. In turn, the exposure of the mummified severed second finger of the left hand in Ratnevsky solution No. 2 significantly reduced the required exposure time compared to the soap solution, but did not ensure prompt restoration of the papillary pattern. The MF24 solution allows you to reduce the required time for pattern restoration to 12 hours, which significantly speeds up the identification process. The print of the restored fourth finger of the left hand is of higher quality due to a clearer image of the papillary pattern, its contrast and completeness. Conclusions. The described methods for restoring papillary patterns using Ratnevsky solution No. 2 and MF24 solution are generally available, since they do not require expensive chemical compounds and special technical equipment for implementation. This makes them economical and possible for use in all regional forensic medical examination bureaus, regardless of material and technical support.
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