Microbial assessment & quantification following placement of different sealing materials at the screw abutment connection under loading conditions in dental implants A metagenomic study

The leakage of microorganisms and fluids to the inner parts of the implants is considerably increased by load application, which generates micro-movements and interfacial gaps. (Khraisat et al., 2006). Bacterial species harboring the internal surfaces of the implants and components is not surprising, since the size of oral bacterial species ranges in average from 1.1 to 1.5 μm in length and 2 to 6 μm in diameter. Smaller species like spirochetes (diameter of 0.1 to 0.5 μm) may also be found in the oral microbiota. (Jansen et al., 1997).

Micro gaps between implant and abutment are generally less than 10 um. Given access to the microgap, bacteria can easily penetrate even through the tightest implant-abutment fittings. Biofilms and bacterial colonization of dental implants. According to Quirynen et al. (2002), gaps in the implant-abutment interface may act as a trap for bacteria, favoring the development of biofilm with varying composition and impact on periodontal tissues. AA, T forsythia and P gingivalis, many times present in these biofilms, are pathogens intimately related to the development and maintenance of periodontitis and peri-implantitis. Considering the increased use of dental implants and recognizing the impact of bacterial leakage along the implant-abutment interface on the health of peri-implant tissues this study was planned.

 ABOUT METAGENOMICS-The next culture-independent game changer

  Recently, metagenomics was defined as "the application of modern genomics techniques to the study of communities of microbial organisms directly in their natural environments, bypassing the need for isolation and lab cultivation of individual species".

There is no defined consensus among implantologists’ with regard to what is ideal material when it comes to

sealing the implant abutment connection. More so, very few studies have been undertaken under loading

conditions. Different variation of materials have been taken, some new types (e.g. temporary composite

material) to find the best possible combination. This study was therefore planned to reduce the ambiguity with

regard to this very important clinical parameter under loading conditions. Since microbes comprise the primary

factor with regard to implant failure, determining specific microbial niches is of paramount importance and this

study will help us find specific microbial niches (identification and quantification) which can exist with regard

to different sealing agents placed in implant abutment screw hole. Also, swab will be taken around the implant

fixture before placement of abutment as that will act as the control group. So this study was planned to include

highly specific and advanced technique of metagenomics for all cases of implant placement three months after

loading using different sealing materials in implant abutment screw hole.