1997 Volume 43 Issue 12 Pages 903-911
We studied procedures for freeze-drying and changes in mechanical properties of extracted human ribs. To establish the basis for clinical application, we freeze-dried human extracted ribs. We measured residual moisture and tested the mechanical properties of the ribs and obtained the following results.
1. When the ribs were freeze-dried, the residual moisture of the ribs tended to gradually decrease. This phenomenon was observed after a prolonged duration of freeze-drying following equalization of the inside temperature of the ribs and the chamber temperature.(This decrease in moisture is generally seen on completion of the drying procedure.) Freeze-drying decreased the residual moisture content to below 5%.
2. We found no distinct difference in the three-point bending strength and the compression strength of male ribs, even when the freeze-drying time was prolonged. The results show that freeze-drying treatment does not diminish rib strength.
3. The fracture toughness value of human ribs (male) processed by freeze-drying was 1.29±0.68MPa√m on average.
