The influence of different abutment materials on tissue regeneration after surgical treatment of peri-implantitis - a randomized controlled preclinical study

Abstract Objectives This study aimed to assess the impact of different abutment materials on peri-implant tissue regeneration after surgical treatment of peri-implantitis in a large animal model. Material and Methods Titanium implants ( n = 51) were inserted in the upper and lower jaw of eight beagle dogs and a peri-implant infection was induced. After two months the peri-implant infection was surgically treated and abutments with different surfaces (Ti-2: n = 14; CoCrMb: n = 13; Ag-modified Ti-4: n =14; Ti-4 control: n = 10) were applied. Clinical attachment level (CAL), modified sulcus bleeding index (mBI), bleeding on probing (BoP), and the sulcus fluid flow rate (SFFR) were determined 4, 8, and 12 weeks after surgical treatment to document the peri-implant tissue reaction. Results Superior levels for CAL and mBI were found with the Ti-4 control and the Ag-modified abutments, with the Ag-modified abutments showing the best values after 12 weeks. Lowest SFFR values compared with the other treatment groups underlined the superior soft tissue reaction adjacent to Ag-modified abutments. After 12 weeks inferior CAL, SFFR, BOP and mBI values were documented for the Ti-2 surface. Conclusion Within limitations of the study, Ag-modified abutments lead to superior tissue reactions. Further studies are needed to investigate the properties of abutment materials.