Evaluation of the effect of early bacterial colonizers on the surface of retrieved dental healing abutments

摘要

Figure 1b showed a characteristic surface discoloration in group 1. The characteristic yellow and blue discoloration observed with the implants in group 1 can be associated with oxidation of titanium to Ti~(3+)/Ti~(4+). This feature could be attributed to the electrochemical attack on the surface due to the acidic oral environment created by the early colonizing bacteria. In group 2. color coding of HA made it difficult to characterize discoloration. Mechanical wear observed on HA may be due to the insertion/removal of HA during surgery as HA are not exposed to functional loading. The XPS data of dental implant immersed in S. mutatis clearly showed the breakdown of oxide layer and exposure of the bulk. The ability of bacteria to adhere to the surface and release metabolic products was further confirmed with the presence of Iron which is one the main metabolic constituents of S.mutans. In the XPS analysis of retrieved HA. no destruction of the surface passivity was observed. This may be due to the smooth surface of HA which is inhospitable for bacterial colonization and multiplication compared to the rough surface. Thus. HA have lower susceptibility for bacterial colonization and experience minimal damage on the surface. Dental implants are typically rough and composed of modular parts in comparison to HA. Therefore, it is important to understand how bacteria adhere and proliferate on the surface and interfaces of these implants.