Effect of Enamel Matrix Derivative or Hyaluronic Acid on Non-Surgical Treatment of Peri-Implantitis

After submarginal instrumentation (i.e., titanium curettes plus oscillating chitosan brush), implant surfaces will be conditioned for 2 min with 24% ethylene-diaminetetraacetate EDTA (PrefGel®, Institut Straumann AG). Then, the sites will be completely rinsed with saline solution and thoroughly dried with air. Repeated irrigation and air-drying will be done in the area until complete bleeding control with sterile gauzes. Then EMD (Emdogain®, Institut Straumann AG) will be gently applied with a blunt-tipped sterile syringe until overflowing from the mucosal margin.

After submarginal instrumentation of the implant surface (i.e., titanium curettes plus oscillating chitosan brush), the cross-linked hyaluronic acid gel composed of a mixture of cross-linked (1.6%) and natural (0.2%) will be will be implemented to the peri-implant pockets.

Implants allocated to the control group will be treated with the same sub-marginal instrumentation (i.e., titanium curettes plus oscillating chitosan brush). Implant surface will be irrigated with with sterile saline.