Fall out samples were collected on blood
agar plates placed in six different sectors, 0.5e2 m from the patient. Restorative
dentistry fallout samples (N ¼ 72) were collected from rooms
(N ¼ 6) where high-speed rotating instruments were used, and control samples
(N ¼ 24) were collected from rooms (N ¼ 4) used for periodontal and
orthodontic treatment where rotating and ultrasonic instruments were
not used.