Untersuchung zur Resorption von Poly (D,L)lactid-poly Glycolid copolymer durch parodontopathogene Bakterien -In-vitro-Untersuchung-

Englischsprachige Zusammenfassung Polylactide membranes are used in periodontal surgery for the regeneration of inflammatory lost periodonts. The aim of the work was to investigate in vitro to what extent esterase-active germs found in connection with periodontitis are able to influence the degradation and thus the stability of the membranes. Degradation of self-made 50:50 (D, L) lactide-glycolid films under anaerobic conditions with and without bacterial exposure was compared and micromorphologically, visually, palpatorically, by weighing and with the REM. Visually and palpatorically, differences in the mechanical handling of the foils were noticeable during the five-week experiment compared to cases without and with bacterial contamination. However, the percentage weight loss obtained by weighing did not reveal any statistically relevant differences between the bacterial cases or compared to the non-bacterial control, which suggests that the selected bacteria have only a marginal influence on degradation. Weight loss remained in the single-digit percentage range with and without bacteria during the first 20 days, but then increased steeply and reached levels of 85% after 35 days. Examination of the film surface with the REM showed very striking and also different changes between the bacteria after the first 7 days, but at the end of the test after 35 days, these changes were no longer so conspicuously different from the control without bacteria. This is interpreted to mean that the self-made films were not homogeneous across their cross-section, so that they decayed internally hydrolytically, while the bacteria primarily attacked the skin-like surface. Only a small proportion of these analyses could be performed on the Vicryl® membranes. There were no contradictions in the results. The significance of the test result is that a catalytically accelerated degradation of polylactide membranes by bacterial esterases could be excluded. However, a bacterial attack can change the mechanical properties and thus the stability of a membrane. This is in line with the results of long-term in vivo studies, which have shown that the surgical procedure only leads to lasting healing success in combination with regular follow-up examinations and careful dental care.