Susceptibility of a polycaprolactone-based root canal filling material to degradation. Evidence of biodegradation from a simulated field test

Purpose: To examine if Resilon, a polycaprolactone-based root filling material, was susceptible to microbial biodegradation by using a simulated field test that consisted of incubating the material in wet dental sludge under mesophilic and aerobic conditions. Methods: Pressed disks prepared from Resilon, polycaprolactone (positive control) and gutta-percha (negative control) were incubated in wet dental sludge for up to 4 months and examined for topographical changes using scanning electron microscopy. Results: Gutta-percha exhibited minimal changes in surface integrity, while polycaprolactone and Resilon exhibited severe surface pitting and erosion. In the latter, disappearance of the polymer matrix was accompanied by exposure of mineral and bioactive glass fillers. Bacteria and hyphae-like structures were present on the disk surfaces.