563 patients were put at risk from dirty instruments Posted on 24th May 2019 at 10:26 am.Written by Lynette Devlin Shared from Sky News: Patients at Hertfordshire dental practice told they need HIV tests due to unclean equipment https://news.sky.com/story/patients-at-hertfordshire-dental-practice-told-they-need-hiv-tests-due-to-unclean-equipment-11724645