Comparison of Rehydration Techniques for Fingerprinting the Deceased after Mummification

Abstract

Postmortem decay causes fingertip decomposition, desiccation, shriveling, and rigidity, reducing the possibility of obtaining sufficiently clear fingerprints for identification. In this study, five rehydration solutions (ammonium hydroxide, sodium carbonate, potassium hydroxide, urea, and warm water) followed by three fingerprint recording methods (photograph, inking roll, and dusting tape) were investigated to process mummified fingertips from an unidentified cadaver. The results show that sodium carbonate treatment is the most effective for minutiae restoration, followed by ammonium hydroxide treatment. This study also demonstrates that even those fingertips that previously failed in urea solution, 1% potassium hydroxide solution, and warm water treatment could be further improved with sodium carbonate solution to obtain qualified minutiae for fingerprint matching. The optimal procedure is rehydrating the desiccated fingertips with sodium carbonate solution for 24 h followed by dusting the finger and transferring the print to adhesive tape.

Technical note: Preparation improvement of charred cadaveric viscera using sandison’s rehydrating solution for histological analysis

“…The use of different rehydrating solutions is increasingly taking place in various forensic procedures: for identification protocols on mummified phalanges [6], in the entomologic field for the procedures involving Diptera larvae [7], on cadavers undergoing colorativo/emphysematous phenomena in order to evaluate the cutaneous furrow cause by hanging mechanical asphyxia [8] and on cutaneous samples undergoing peculiar putrefactive phenomena-corification and mummification [9] in order to improve the histological examination…”

Two Novel Methods for Enhancing Postmortem Fingerprint Recovery from Mummified Remains

“…The authors have recently published a technique for obtaining routine postmortem fingerprints using fingerprint powder and adhesive labels , a method that has been used for many years by the authors and occasionally reported by others . Despite the ease of using this powder and adhesive method, challenging cases still exist.…”

“…For desiccated fingers, it has traditionally been suggested to remove fingers and chemically rehydrate using sodium or potassium hydroxide . Other practitioners suggest only removing and rehydrating the finger pad and recently, a test of different rehydration techniques found that a sodium carbonate soak followed by fingerprint dusting transferred to adhesive tape produced the best results . Other methods involve simply photographing the finger with oblique lighting or using modeling clay or Mikrosil to obtain a three‐dimensional imprint of the finger pad.…”

“…It can be nearly impossible to obtain suitable prints from mummified fingers because of the shrunken, wrinkled, and hardened finger pads. The forensic literature includes multiple methods for optimizing postmortem fingerprint acquisition (1)(2)(3)(4)(5)(6)(7)(8)(9)(10). Despite these recommendations, obtaining useable prints is not always possible.…”

Papaya and pineapple juices facilitate rehydration of mummified dermal tissue for fingerprint capture

“…In such cases where the tissues of the finger pads have become completely mummified and no visible friction ridges are available, the samples are essentially unprintable. In order to obtain quality dermatoglyphs for identification, the finger pad tissue must be rehydrated to restore the pliability critical for accurate prints [2]. The standard techniques used to address this problem, such as 3% sodium hydroxide (NaOH) solutions, can be corrosive, and thus damage the already structurally vulnerable tissues [3].…”