IADR Abstract Archives
Bacterial Degradation of Resin Composite Surfaces: An In-vitro Study.
Objectives: The oral bacterial biofilm is a structurally and functionally advanced system amply able to colonize every non-shedding surface in the oral cavity, including resin composites. Microcosm biofilms thrive via effectively manipulating their living environment, thus inducing structural and topographic damage to the resin composite substrate. This study aims at investigation of a multicenter biofilm model, produced from oral inoculums.
Methods: Six identical composite samples (d:1,5 cm), made from Filtek Z250 resin composite (3M ESPE), were prepared for the study. The experimental design included in vitro incubation of five samples for 15 days in a CDC Bioreactor system. These five formed the Test Group, while the sixth disk was contained in a sterile petri dish for 15 days – Control Sample. The incubation process was performed in two consequent cycles: active and passive. The active cycle included continuous flow of fresh growth medium for 72 hours, while the passive cycle included 12 days of uninterrupted incubation with pooled medium. After the successful incubation, all of the test composite samples were freed of biofilm load. All six samples (Test Group and Control sample) were subjected to SEM-analysis for evaluation of structural and topographic changes on the composite surface.
Results: The observed SEM-images of all samples from the Test Group revealed patterns of increased micro roughness, increased micro porosity, layers of grooves and overall surface deterioration. These findings cannot be attributed to passive erosion or any other shear forces due to their particular pattern and followed motives.
Conclusions: The observed alterations to the composite resin surface may be a result of the bacterial metabolism as their role in adhesion and interlocking of surface-associated biofilms is yet to be discussed.
Methods: Six identical composite samples (d:1,5 cm), made from Filtek Z250 resin composite (3M ESPE), were prepared for the study. The experimental design included in vitro incubation of five samples for 15 days in a CDC Bioreactor system. These five formed the Test Group, while the sixth disk was contained in a sterile petri dish for 15 days – Control Sample. The incubation process was performed in two consequent cycles: active and passive. The active cycle included continuous flow of fresh growth medium for 72 hours, while the passive cycle included 12 days of uninterrupted incubation with pooled medium. After the successful incubation, all of the test composite samples were freed of biofilm load. All six samples (Test Group and Control sample) were subjected to SEM-analysis for evaluation of structural and topographic changes on the composite surface.
Results: The observed SEM-images of all samples from the Test Group revealed patterns of increased micro roughness, increased micro porosity, layers of grooves and overall surface deterioration. These findings cannot be attributed to passive erosion or any other shear forces due to their particular pattern and followed motives.
Conclusions: The observed alterations to the composite resin surface may be a result of the bacterial metabolism as their role in adhesion and interlocking of surface-associated biofilms is yet to be discussed.