人類恆牙使用美白藥劑後對矯正用複合樹脂黏著強度之影響

The purpose of this study was to evaluate the bleaching effect of a 35% hydrogen peroxide (H2O2) agent activated with halogen light on the tensile bond strength of human teeth. In total, 75 human third molars extracted from 20- to 35-year-old patients were randomly divided into 5 groups (groups A to E) of 15 teeth each. Group A received no treatment and served as the control group. Groups B, D, B were treated with 35% H202 for 1, 2, and 3 cycles, respectively, then immersed in water for 24 hours. Group C was treated with 35% HO for 1 cycle then immersed in water for 3 weeks. Following treatment, a bracket was bonded to the enamel surface of each tooth with orthodontic composite resin and then debonded on a testing machine. The failure interface was also analyzed with scanning electron microscopy and energy-dispersive x-ray spectrometry. The tensile bond strengths of groups A to B were 10.62±1.82, 10.70±1.87, 10.58±1.66, 10.55±2.20 and 10.73±1.80 MPa, respectively. One-way ANOVA showed no statistical significance among any 2 groups. We concluded that the use of 35% H2O2 does not influence the tensile bond strength within the recommended number of bleaching cycles. However, etching with 37% H3PO4 for 15 seconds is reported to be a cause of enamel fractures.