Table 2.
Summary of characteristics of included studies.
| Author/year | Design of study | Patients, n | Mean age (range) | Frequency of use (time) | Evaluation time | Evaluation methods | Groups, n | Color mean (SD): Reduction in score | Difference between groups | Effect of whitening dentifrice | ||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Follow-up period | Whitening dentifrice | Control group | ||||||||||
| Ghassemi et al. 2012 [23] | Randomized controlled trial | 135 | 38,9 (19–70) | Twice daily (1 minute) | 4 and 6 weeks | Shade guide |
G1: Arm & Hammer advanced white (n=86) G2: Crest cavity protection toothpaste (n=49) |
Week 4 | (G1) 1.82 (0.80) | (G2) 0.07 (0.42) | G1∗ × G2 p < 0.0001 | Positive |
| week 6 | (G1) 2.57 (0.99) | (G2) −0.04 (0.69) | G1∗ × G2 p < 0.0001 | Positive | ||||||||
|
| ||||||||||||
| Ghassemi et al. 2015 [24] | Randomized controlled trial | 178 | 38,5 (18–75) | Twice daily (2 minutes) | 5 days and 2, 4, and 6 weeks | Shade guide |
G1: Truly radiant toothpaste (n=59) G2: Crest 3D white radiant mint toothpaste (n=56) G3: Colgate cavity protection toothpaste (n=63) |
Day 5 | (G1) 0.597 | (G3) −0.08 | G1∗ × G2 p=0.0105 | Positive |
| (G2) 0.324 | G1/G2∗ × G3 p < 0.0001 | |||||||||||
| week 2 | (G1) 1.172 | (G3) 0.046 | G1 × G2 p=0.1595 | Positive | ||||||||
| (G2) 0.837 | G1/G2∗ × G3 p < 0.0001 | |||||||||||
| week 4 | (G1) 1.170 | (G3) 0.107 | G1 × G2 p=0.2409 | Positive | ||||||||
| (G2) 1.326 | G1/G2∗ × G3 p < 0.0001 | |||||||||||
| week 6 | (G1) 2.081 | (G3) 0.038 | G1∗ × G2 p=0.0383 | Positive | ||||||||
| (G2) 1.467 | G1/G2∗ × G3 p < 0.0001 | |||||||||||
|
| ||||||||||||
| Gerlach et al. 2001 [20] | Randomized controlled trial | 278 | 43,9 (19–79) | Twice daily (NI) | 4 and 8 weeks | Shade guide |
G1: crest extra whitening (n=144) G2: Arm & Hammer dental care dentifrice (n=134) |
Week 4 | (G1) 1.04 | (G2) 0.53 | No difference | None |
| week 8 | (G1) 1.42 | (G2) 0.96 | G1∗ × G2 p < 0.05 | Positive | ||||||||
|
| ||||||||||||
| Isaacs et al. 2001 [21] | Randomized controlled trial | 654 | 43 (NI) | Twice daily (NI) | 4 and 8 weeks | Spectroscopy |
G1: Crest extra whitening (silica) (n=219) G2: Colgate baking soda and peroxide (n=216) G3: Crest cavity protection (n=219) |
Week 4 | (G1) 0.05 | (G3) −0.14 | G1∗ × G3 p=0.007 | Positive |
| (G2) 0.08 | G2∗ × G3 p=0.002 | Positive | ||||||||||
| week 8 | (G1) 0.03 | (G3) −0.25 | G1∗ × G3 p < 0.001 | Positive | ||||||||
| (G2) 0.10 | G2∗ × G3 p < 0.001 | Positive | ||||||||||
| G1 × G2 No difference | ||||||||||||
|
| ||||||||||||
| Kakar et al. 2004 [22] | Randomized controlled trial | 44 | 34,15 (NI) | Twice daily (2 minutes) | 2 weeks and 4 weeks | Shade guide |
G1: Colgate simply white (n=21) G2: control dentifrice (n=23) |
Week 2 | (G1) 4.04 (1.40) | (G2) 0.41 (0.55) | p < 0.05 G1 | Positive |
| week 4 | (G1) 5.17 (1.09) | (G2) 0.53 (0.63) | p < 0.05 G1 | Positive | ||||||||
|
| ||||||||||||
| Horn et al. 2014 [25] | Randomized controlled trial | 60 | NI (19–36) | Three times a day (2-3 minutes) | 2 weeks | Spectroscopy | G1: Colgate total 12 (n=15) G2: Close-Up white now (n=15) G3: Oral B 3D white (n=15) G4: Colgate luminous white (n=15) |
Week 2 | (G2) −0.7 | (G1) −1.1 | G1 × G2 or G3 No difference | None |
| (G3) −0.3 | ||||||||||||
| (G4) −1.7 | ||||||||||||
| G4∗ × G1 p=0.01 | Positive | |||||||||||
|
| ||||||||||||
| Pintado-Palomino et al. 2016 [7] | Randomized controlled trial | 50 | 22,9 (19–36) | Three times a day (2-3 minutes) | 4 weeks | Spectroscopy |
G1: Colgate luminous white (n=17) G2: Close-Up white now (n=16) G3: Sorriso (n=17) |
Week 4 | (G1) 5.1 (2.8) | (G3) 4.4 (3.0) | No difference | None |
| (G2) 6.8 (3.5) | ||||||||||||
∗Groups with significant statistical difference. NI, not informed.