This study compared the bacteriological effect and clinical finding of two different designs of abutments in tooth supported over denture.
Materials and Methods: Twenty male completely edentulous patients were selected and randomly divided into two equal groups according to the abutments design. Group 1: Patients were rehabilitated with complete over denture supported by two dome shaped endodontically treated teeth with composite plug. And Group 2: Patients were rehabilitated with complete over denture supported by two dome shaped Endodontically treated teeth with zirconium post and coping. The Microbiological swabs were collected from buccal, lingual, mesial and distal surfaces of the abutment for each patient in order to evaluate the bacterial colonization. On other hand, the clinical assessment was done including pocket depth evaluation. at the time of insertion, 3, 6, 9 and 12 months after over denture insertion. The data were collected and statistically analyzed. Results: The quantitative bacterial culture from each group of patients ( n=10) had revealed statistical significant increase the percentage of bacterial count in (group I) of patients that were wearing over dentures without coping compared to the other group of patients (group II) that were wearing over dentures with zirconium coping with statistical significant difference( p<.0.001<.0.001) and regarding the clinical assessment there was no statistical significant difference between two groups .
Conclusion: Abutments supported over denture with zirconium copings as regard to bacterial and clinical assessment are much better for oral hygiene maintenance than abutments without copings. Further studies are recommended by other experimental means like Electron Microscopy, other bacterial species to support this research.