{'fraction_non_alphanumeric': 0.04684418145956608, 'fraction_numerical': 0.04339250493096647, 'mean_word_length': 4.864161849710983, 'pattern_counts': {'":': 0, '<': 2, '<?xml version=': 0, '>': 1, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
[Efficacy of one year treatment of icon infiltration resin on post-orthodontic white spots].

OBJECTIVE
To clinically evaluate the effectiveness of icon infiltration resin on masking post-orthodontic white spots.


METHODS
Eight post-orthodontic patients with 6 maxillary anterior teeth showing signs of decalcification (total 48 teeth) were enrolled in this study. All teeth were treated with icon resin infiltration according to manufacturer's recommendation. Standardized digital photographs were taken before, immediately after and 1 week, 6 and 12 months after treatment. Before taking pictures the assigned teeth were cleaned using pumice and rubber polishing cups. The results were classified into three groups: completely masked, partially masked, and unchanged. Pictures of partially masked teeth were analyzed using image analysis software (Image-pro plus 6.0), size of the white spot lesion (W) and the whole tooth facial surface (T) were measured, then W/T ratio (in %) was calculated. The images were imported into image analysis software (Photoshop) which presented the images into histograms of gray scale from (0 to 255).


RESULTS
Among the 48 teeth, 11 teeth (22.9%, 11/48) were classified as completely masked, whereas 37 teeth (77.1 %, 37/48) were classified as partially masked and no tooth unchanged. For partially masked teeth, W/T ratio decreased significantly after treatment from 31.37% to 7.99% (by Wilcoxon's signed rank test, P<0.05). The means at gray scale for the initial and 1 week photographs after treatment were 188.07± 5.62 and 143.20± 7.03 respectively, and there was significant difference by Wilcoxon,s signed rank test (P<0.05). The data of 6 and 12 months after treatment were 136.33± 4.54 and 139.57± 3.70 respectively, there were no significant differences (P>0.05) in comparison to 1 week after treatment.


CONCLUSION
Resin infiltration was proven to be an effective treatment for masking white spot lesions. The surface color of infiltrated lesions remained stable after 12 months.