The study by Frank Schwarz and his co-authors is a key-publication on peri-implantitis. It compared the ligature-induced peri-implantitis with naturally occurring peri-implantitis defects. Alberto Monje talked to Frank Schwarz about this study online on 28 May 2020, suring a time when personal meetings were not possible due to the COVID-19 pandemic. They discussed about defect configuration and implications this study had on the daily clinical practice in the treatment of peri-implantitis. But Frank Schwarz also shared some insights how he treats peri-implantitis cases as a clinician, and shared his huge experience from his department where about 400 patients per year are undergoing reconstructive measures.