Study Year of
publication 		Follow-up Study design Group N Age
(years) 		Habit duration
(years) 		Daily
frequency 		Duration of
each session
(min) 		Brushing (%) Number of
implants 		Implant duration
(months/years)
Once Twice
Mean (SD) Mean (SD) Mean (SD) Mean (SD) Mean (SD)
ArRejaie et al. [57] 2019 NR Cross-sectional CS 32 40.4 (3.5) 13.7 (7.2) 11.3 (2.5) min 10.4 (2.1) 69 31 59 54.9 (16.1)
VS 31 35.8 (6.2) 4.4 (1.8) 6.5 (0.9) min 37.7 (11.3) 56 44 49 48.2 (14.8)
NS 32 42.6 (2.7) NR NR NR 60 40 51 45.6 (20.4)
AlQahtani et al. [58] 2019 NR Cross-sectional CS 40 45.8 (6.8) 21.3 (5.2) 14.6 (3.8) min 8.1 (0.7) 81 19 71 55.7 (8.9)
WS 40 43.5 (4.9) 19.5 (2) 5.9 (1.1) min 31.6 (2.2) 68 32 65 59.4 (14.7)
VS 40 35.6 (7.1) 8.7 (3.8) 6.5 (0.9) min 37.3 (11.3) 56 44 62 50.6 (12.9)
NS 40 42.6 (2.7) NR NR NR 60 40 55 47.2 (20.5)
Al-Aali et al. [59] 2018 NR Cross-sectional VS 47 35.8 (6.2) 4.4 (1.8) 6.5 (0.9) min 37.7 (11.3) 56 44 68 51.8 (13.7)
NS 45 42.6 (2.7) NR NR NR 60 40 57 47.2 (20.5)
Alqahtani et al. [60] 2019 NR Cross-sectional CS 35 36.3 (1.2) 10.2 (4.1) NR 6.6 (0.5) NR NR 35 1.6 (0.4)
WS 33 34.1 (1.4) 8.3 (0.4) 5.1 (0.3) times/day 16.3 (2.4) NR NR 33 1.3 (0.2)
VS 34 33.5 (0.7) 3.5 (0.6) 14.3 (1.2) times/day 5.1 (0.6) NR NR 34 1.4 (0.2)
NS 35 32.2 (0.6) NR NR NR NR NR 35 1.3 (0.2)
Sinha et al. [61] 2020 NR Cross-sectional VS 47 34.6 (6.1) 53.2 (13.7) 4.6 (1.8) min 6.8 (0.9) 54 46 66 45 (21)
NS 45 44.8 (2.5) 51.2 (19.5) NR NR 58 42 55 35 (20)
Ali et al. [62] 2023 NR Cross-sectional CS 25 51.3 (5.2) 20.2 (3.5) NR NR 80 20 25 7.1 (1.6)
WS 24 53.8 (2.4) NA NR 22.1 (5.5) 72 28 24 8 (0.4)
NS 25 49.6 (0.9) NA NR NR 24 76 25 7.2 (0.5)
BinShabaib et al. [63] 2018 NR Case-control CS 34 50.3 (3.5) 22.3 (3.7) 17.4 (2.2) times/day 8.5 (0.6) NR NR 41 NR
WS 33 44.5 (2.8) 14.5 (2.8) 5.2 (0.4) times/day 29.5 (2.1) NR NR 37 NR
NS 31 42.6 (0.7) NR NR NR NR NR 35 NR
Al-Sowygh et al. [64] 2018 NR Case-control WS 21 43.4 (4.1) 18.5 (3.5) 5.5 (0.3) min 33.5 (8.6) 76.1 23.9 NR NR
NS 19 45.3 (3.5) NR NR NR 84.2 15.8 NR NR
Alazmi et al. [65] 2021 8 years Retrospective cohort VS 63 34.2 (1.3) 9.3 (0.5) NR NR 17.5 82.5 75 8.8 (0.4)
NS 64 35.1 (0.5) NR NR NR 14.1 85.9 82 8.5 (0.2)

NR = not recorded; CS = cigarette smokers; WS = waterpipe smokers; VS = vape smokers; NS = non-smokers; N = number; SD = standard deviation.