Abstract: Objective To evaluate the effect of chair-side heating bleaching on teeth with different positions. Methods 6 patients were selected to join in the test according to the inclusion criteria. Three sessions for 15 minutes using a chair-side heating bleaching system were performed as one bleaching treatment, and the interval between each two sessions was one day. Colors of maxillary central incisor, lateral incisor, and canine were registered each session and 1 week or 1 month after completing the treatment by a dental colorimeter, registering parameters L*, a*, b*, color difference values, and whiteness values. Results There was no significant difference of color difference values and whiteness difference values among the three different teeth positions (P?0.05). Color difference values and whiteness difference values also showed no difference among the three bleaching sessions, and 1 week or 1 month after completing the bleaching treatment (P?0.05). Conclusion Chair-side heating bleaching exerts the same effect on teeth with different positions.

Key words: bleaching teeth, heating, constant temperature, color parameter