Experimental study on the therapeutic effect of different bleaching methods on white-spot lesions of the enamel using optical coherence tomography
10.13591/j.cnki.kqyx.2023.03.005
- VernacularTitle:光学相干成像无创检测不同漂白方法对釉质白斑治疗效果的实验研究
- Author:
Yingmei LI
1
;
Peng KOU
;
Yuxin CHEN
;
Qingqing WANG
;
Ke NI
;
Yan WANG
;
Qingfei MENG
Author Information
1. College of Stomatology, Bengbu Medical College, Bengbu 233000, China
- Publication Type:Journal Article
- Keywords:
white-spot lesion;
resin infiltration;
in-office bleaching;
microhardness;
optical coherence tomography
- From:
STOMATOLOGY
2023;43(3):217-221
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the efficacy of different bleaching methods on white-spot lesions of the enamel using optical coherence tomography and to evaluate its feasibility for monitoring the therapeutic effects on white-spot lesions.
Methods:Forty-eight sound premolars extracted for orthodontic reasons were selected and cut for 4 mm×4 mm×2 mm enamel blocks in buccal surfaces of the crowns. The samples were covered with acid-resistant varnish (except for the buccal surfaces) and immersed in demineralization solution for 18 days to establish the white-spot lesion models of the enamels. Samples were randomly divided into four groups (n=12). Group A was given demineralization only. Specimens in Group B, C and D were treated with 40% hydrogen peroxide, resin infiltration and 40% hydrogen peroxide combined with resin infiltration, respectively. Eight samples in each group were randomly selected. OCT was applied to observe the optical changes of the enamel surface and according to the OCT scanning results, the demineralization depth of enamel samples in each group was calculated. Then, the enamel blocks were embedded in epoxy resins, except the buccal surfaces, and measured for the microhardness values of the enamel surface by a microindentation hardness tester. Four samples in each group were cut longitudinally, and the ultrastructural changes of enamel samples in each group were observed by scanning electron microscope.
Results:OCT showed that the light scattering characteristics of enamel surface changed in all groups, and the bright layer was formed, but the thickness of bright layer in Group C and D was significantly lower than that in Group A and B (P<0.05). The microhardness values (kg/mm2) of the samples in Group A-D were (214.99±31.70), (250.66±33.64), (312.42±18.01) and(286.53±26.65), respectively. The microhardness of enamel surfaces in Group C and D was significantly higher than that in Group A and B (P<0.05), and the ultrastructure of enamel surfaces in Group C and D were more flat and dense in SEM observation (P<0.05).
Conclusion:The methods of resin infiltration therapy or 40% hydrogen peroxide combined with resin infiltration could effectively improve white-spot lesions of the enamel and the non-invasive OCT can be used as a better evaluation method for the diagnosis and treatment of white-spot lesions of the enamel.
