PATIENT SATISFACTION AND MASKING OF WHITE SPOT LESIONS AFTER HOME WHITENING WITH 10% CARBAMIDE PEROXIDE

The lesions will be characterised as described above at 4 weeks and one month after the end of the whitening treatment. If the whitening treatment is prolonged, this will also be done at the end of the treatment. The effectiveness of masking will be determined by the colour difference between the lesions and the surrounding tissue using the CIELAB formula (De L'Eclairage, 1978):

∆Eab = [(∆L*)2 + (∆a*)2 + (∆b*)2]1/2. By definition, a tooth is considered masked when the colour difference (ΔEab) between the lesions and the surrounding healthy enamel is ΔEab ≤3.7, and unmasked if ΔEab > 3.7. A colour difference below the acceptability threshold of 3.7 was chosen as an indicator of masking.

In addition, the colour change will also be calculated using the CIEDE 2000 formula:

Additionally, the CIEDE2000 formula will be applied;

∆E00 = [(ΔL/kLSL)2 + (ΔC/kCSC)2 + (ΔH/kHSH)2 + RT(ΔC*ΔH/SC*SH)]1/2

and the whiteness index (WI)

We will assess sensitivity and intensity using a visual analogue scale (VAS) from 0 to 10. Each patient will be given a diary covering the two weeks between appointments, which they will have to fill in daily. Zero will represent 'no pain' on the visual analogue scale and ten will represent 'severe pain'. Patients will be asked to record the worst result once a day, even if there has been no pain, marking with a vertical line the value corresponding to the intensity of their tooth sensitivity, which will then be measured in centimetres. If the patient marks any value above zero, it will be interpreted as tooth sensitivity. In cases of severe sensitivity, desensitising agents or analgesics/anti-inflammatories will be dispensed.

We will assess gingival irritation and the intensity of said irritation using a visual analogue scale (VAS) from 0 to 10 by means of a diary that will be provided together with the dental sensitivity diary, which the patient will fill in the same way, with zero being 'no gingival irritation' and ten being 'severe irritation'. Patients will be asked to record the worst result once a day, even if there has been no irritation, marking with a vertical line the value corresponding to the intensity of gingival irritation, which will then be measured in cm.

We will assess the appearance of new lesions during treatment using a visual analogue scale (VAS) from 0 to 10 in a diary that will be provided along with the tooth sensitivity diary, which the patient will fill out in the same way, with zero being 'very dissatisfied' and ten being 'very satisfied'. Patients will be asked to record the worst result once a day by marking with a vertical line the value corresponding to the intensity of gingival irritation, which will then be measured in centimetres.