Purpose: The purpose of this study was to evaluate the impact of titanium and zirconia abutments on the health of preimplant tissue. Methods: Twenty completely edentulous patients have been selected from the outpatient clinic in the removable prosthodontic department, faculty of dental medicine for girls, Al-Azhar University. A complete maxillary denture and an implant supported mandibular overdenture were constructed. Six and nine months after denture placement, clinical evaluation (plaque index and gingival index) and microbiological assessment (Candida albicans colonization) of the implant have been carried out. Results: this study showed the titanium abutment had higher significance difference in plaque index, gingival index and Candida colonization than zirconia abutment. Conclusion: The use of zirconia abutments had a significant benefit over titanium abutments in maintaining the health of the soft tissue around implants in mandibular implantsupported overdentures, within the limitations of the follow-up time