Clinical evaluation of different types of teeth in in-office whitening.

Objective: This prospective case series aimed to clinically evaluate the bleaching effect, spontaneous tooth sensitivity and variation in the thermal sensation threshold of different groups of teeth undergoing in-office bleaching.

Method and materials: Ten patients received conventional bleaching treatment: 35% hydrogen peroxide with 3 bleaching sessions of 45 minutes, evaluating color change (ΔE and ΔE00), whitening index (WID), and tooth sensitivity (VAS). Thermal stimulus-generating devices were used to simulate sensitivity caused by low temperatures through Quantitative Sensory Tests (QST). Analyses were conducted individually on different teeth groups (n=20) (lower incisors LI, upper incisors UI, canines C, upper first premolars PM).

Results: Regarding color change, LI and UI did not statistically differ from each other but showed significant difference and greater bleaching potential compared to C and PM (P =.018). Regarding sensitivity, LI and UI presented the highest spontaneous sensitivity values (P =.032), while PM did not display painful symptoms, also observed in provoked sensitivity analysis (P =.025).

Conclusions: The general analysis of the results indicates that the tooth type responds differently to the whitening treatment, both in relation to the aesthetic benefit and the occurrence of tooth sensitivity. It was observed that lower incisors reach the degree of chromatic saturation before canines and premolars, in addition to presenting greater bleaching sensitivity. Personalizing the treatment, based on prior knowledge of the degree of saturation, anatomical factors and the risk of sensitivity, can provide considerable advantages in the whitening technique.