The objective of this in situ study was to evaluate the effects of whitening strip (Claren, LG Household & Health Care Ltd, 2.6% hydrogen peroxide) and gel (Opalescence, Ultradent, 10% carbamide peroxide) on microhardness of enamel in comparison with untreated control. Extracted twenty human upper incisors were disinfected, cleaned, and labial side of each incisor sectioned into 3 fragments by 2 × 2 mm size. After sectioning, labial sides of fragments were flattened and fixed to orthodontic bracket using flowable composite resin. Specimens prepared from each tooth were attached to the labial side of upper incisors of twenty volunteers one by one and treated by three different methods: (1) untreated control (2) treated with whitening strip for 14 days (3) treated with whitening gel for 14 days.

Microhardness (Microhardness tester, Zwick) of each specimen was measured at the baseline of pre-treatment, immediate after bleaching treatment, 14 days after bleaching treatment and Knoop Hardness Number was determined. Microhardness changes of experimental groups were compared.

The results show that tooth whitening strip and gel used in this study does not effect the micro-hardness of enamel during bleaching procedure.

Citations

Citations to this article as recorded by  

• Surface Damage and Bleaching Effect according to the Application Type of Home Tooth Bleaching Applicants
  Na-Yeoun Tak, Do-Seon Lim, Hee-Jung Lim, Im-Hee Jung
  Journal of Dental Hygiene Science.2020; 20(4): 252.     CrossRef
• Effect of the bleaching light on whitening efficacy
  Jong-Hyun Park, Hye-Jin Shin, Deok-Young Park, Se-Hee Park, Jin-Woo Kim, Kyung-Mo Cho
  Journal of Korean Academy of Conservative Dentistry.2009; 34(2): 95.     CrossRef