Treatment of failing dental implants.

Recent studies show that the bacterial flora in adult periodontitis and peri-implantitis are identical, but there could be a more pathogenic flora (gram-negative bacteria, spirochetes) in the partially edentulous implant case than in the fully edentulous implant case. These data indicate a possible seeding mechanism from the natural tooth pocket to the implant crevice and may place the implant in the partially edentulous case more at risk. Also, understanding of the importance of loading in a progressive sense to prevent retrograde peri-implantitis involving the dental implant has increased; the density of bone must be evaluated more fully to determine the time frame necessary to gain a compact bone capable of withstanding occlusal forces at the bone-implant interface.