Table 2.
Tooth color parameter means and standard deviations (±SD) for the different treatment groups according to the evaluation periods
| Color parameters | Treatment groups | Evaluation periods | ||
| T0 (baseline) | T1 (1-week of treatment) | T2 (1-week after treatment) | ||
| ΔL* | Control | A 77.2 (±4.2)a | B 1.9 (±2.4)a | B 2.4 (±3.0)a |
| CP10 | A 76.4 (±4.5)a | B 10.1 (±4.2)b | C 12.1 (±5.6)b | |
| CP16 | A 75.6 (±4.2)a | B 12.6 (±3.7)b | C 15.6 (±6.7)b | |
| CP37 | A 79.3 (±2.8)a | B 5.9 (±2.2)c | B 6.2 (±2.3)c | |
| Δa* | Control | A 2.5 (±2.3)a | B -1.0 (±0.8)a | C -1.7 (±1.6)a |
| CP10 | A 2.4 (±2.9)a | B -2.6 (±1.9)b | B -2.7 (±2.1)a | |
| CP16 | A 1.7 (±2.1)a | B - 2.5 (±1.5)b | B - 2.3 (±1.4)a | |
| CP37 | A 2.5 (±2.4)a | B -2.8 (±2.0)b | C -3.4 (±1.9)a | |
| Δb* | Control | A 36.4 (±5.0)a | B -1.4 (±1.9)a | C -2.7 (±3.4)a |
| CP10 | A 36.1 (±4.2)a | B - 7.6 (±3.1)b | B -7.6 (±2.2)b | |
| CP16 | A 32.0 (±4.0)a | B - 5.8 (±3.4)b | B -5.0 (±3.3)ab | |
| CP37 | A 36.0 (±5.2)a | B - 7.1 (±4.1)b | C - 11.0 (±4.0)c | |
| ΔE | Control | — | A 3.6 (±1.9)a | B 5.5 (±2.9)a |
| CP10 | — | A 13.5 (±3.9)b | A 15.1 (±5.0)b | |
| CP16 | --- | A 14.4 (±3.9)b | B 16.8 (±4.1)b | |
| CP37 | --- | A 10.1 (±3.9)c | B 13.6 (±3.5)b | |
At baseline, L*, a*, b* means were shown in absolute values. Different capital letters indicate statistical significant differences only between evaluation periods (p<0.05). Different lowercase letters indicate statistical significant differences only between treatment groups (p<0.05).