𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Determination of the 3-D morphology of degradable biopolymer implants undergoingin vivo resorption

✍ Scribed by Schliephake, H. ;Klosa, D. ;Rahlff, M.


Book ID
102874202
Publisher
John Wiley and Sons
Year
1993
Tongue
English
Weight
906 KB
Volume
27
Category
Article
ISSN
0021-9304

No coin nor oath required. For personal study only.

✦ Synopsis


A technique is presented that allows the visualization of the degradation process of biopolymers. Serial thicksection specimens containing cross-sections of polydioxanone implants (PDAs) were realigned for 3-D reconstruction using a double-embedding technique. The outlines of the cross-sectioned implants were traced using an automatic image analysis system and converted into x, y , and z coordinates. The reconstruction of the implant body was achieved by the stepwise analysis of vertical relationships between two adjacent section levels. The surface was approximated by triangulation and calculated from the surface triangles. Visualization was achieved by introducing the data into commercially available software using z-buffering and Gouraud shading. The geometric precision of the reembedding technique was found to be 0.8-1.5% of the screen width; recovering experiments showed a good approximation to the actual physical volume of unresorbed implants (+2.6%). The error of volume determination due to the limited resolution in the z direction was calculated to be acceptable (<5.0%) in isotropic objects where the ratio between the radius of the surface curvature and the distance between the sections is >4. Results indicate that large devices of PDAs are degraded in vivo in a fashion similar to that previously described for in vitro degradation of PLA molded screws by a surfacelcenter differentiation with formation of hollow residuals after 17 weeks and complete degradation with phagocytosis of microparticles after 26 weeks.


πŸ“œ SIMILAR VOLUMES