Peri-implant Inflammation Defined by the Implant–Abutment Interface

Abstract

An interface of implant-abutment at the alveolar bone crest is allied with sustained peri-implant inflammation; though, whether extent of inflammation is correspondingly reliant on interface position remains unknown. This study compared the distribution and density of inflammatory cells surrounding implants with a supracrestal, crestal, or subcrestal implant-abutment interface. All implants established a parallel pattern of peri-implant inflammation: neutrophilic polymorphonuclear leukocytes (neutrophils) extremely collected at or proximately coronal to the interface. However, peri-implant neutrophil accrual increased progressively as the implant-abutment interface depth increased, i.e., subcrestal interfaces promoted a significantly greater maximum density of neutrophils than did supracrestal interfaces (10,512 ± 691 vs. 2398 ± 1077 neutrophils/mm2). Moreover, inflammatory cell accumulation below the original bone crest was significantly correlated with bone loss. Thus, the implant-abutment interface dictates the intensity and location of peri-implant inflammatory cell accumulation, a potential contributing component in the extent of implant-associated alveolar bone loss.