Study Age Implant
Dropout Ti implant Zr implant Implant system Implants lost 1 or 2 pieces
Mean (SD) N N N N
Benic et al. [14] NR 2 20 20 (Ti-Zr) Straumann® 0 1
Bienz et al. [15] 55 2 42 42 (Ti-Zr) Straumann® 0 NR
Hassouna et al. [16] NR 0 14 140 NR 0 1
Ioannidis et al. [17] NR NR 20 20 (Zr) Straumann® NR 2
Koller et al. [18] 46 (26) 0 15 16 (Zr) Ziterion® (Vario T; Ziterion) 1 Ti / 2 Zr 2
Müller et al. [19] 72 (8) 16 47 47 (Zr) Ziterion® (Vario T; Ziterion) 1 Ti/1 Ti-Zr 2
Osman et al. [20] 62 (17) 5 56 73 (Zr) Southern implants® 10 Ti/21 Zr 1
Payer et al. [21] 46 (26) 0 15 16 (Zr) Ziterion® (Vario T; Ziterion) 1 Zr 2
Siddiqi et al. [22] 62 (16) 3 70 80 (Zr) Southern implants® 10 Ti/21 Zr 1
Tolentino et al. [23] 43.3 (6) 0 5 5 (Ti-Zr) Straumann® 0 NR

Ti = titanium; Zr = zirconia; Ti-Zr = titanium-zirconium; SD = standard deviation; N = number; NR = not reported.