TY - JOUR
T1 - Three-dimensional assessment of proximal contact enamel using optical coherence tomography
AU - Ei, Thwe Zin
AU - Shimada, Yasushi
AU - Abdou, Ahmed
AU - Sadr, Alireza
AU - Yoshiyama, Masahiro
AU - Sumi, Yasunori
AU - Tagami, Junji
N1 - Funding Information:
This research project was supported by the Research Grant for Longevity Science (29-3) Ministry of Health, Labor and Welfare, Japan and by Grant-in-Aid for Scientific Research ( 16K11544 ) from the Japan Society for the Promotion of Science (JSPS) .
Publisher Copyright:
© 2019 The Academy of Dental Materials
PY - 2019/4
Y1 - 2019/4
N2 - Objective: The purpose of this study was to detect and investigate the association of enamel microcracks with demineralization at proximal contact areas of premolars, using 3D swept-source optical coherence tomography (SS-OCT). Methods: Extracted maxillary and mandibular premolars (n = 50 each), without any visible tooth cracks, were examined for demineralization of interproximal contact areas, using the International Caries Detection and Assessment System (ICDAS). SS-OCT was used to evaluate demineralization and detect microcracks. Demineralization progression was divided into 4 types by depth: 0 for sound enamel and Type I, II, and III for enamel demineralization penetrating into the outer third, the middle third, and the inner third of the enamel thickness, respectively. Enamel microcracks were classified according to the predominant crack pattern: Type O, no cracks; Type A, subsurface microdefects; Type B, enamel microcrack running along the direction of the enamel prism; Type C, enamel microcrack running transverse to the enamel prism direction; and Type D, a combination of patterns A, B, and C. SS-OCT findings were confirmed by confocal laser scanning microscopy observation. Results: Microcracks confined within the superficial enamel in proximal contact areas were seen as bright lines on SS-OCT. There were significant positive correlations among ICDAS codes, demineralization levels, and microcrack distribution (p ≤ 0.001). The mesial side of maxillary premolars showed significantly more demineralization (n = 36) and microcracks (n = 27) than that of the mandibular premolars (n = 20 and n = 14, respectively; p < 0.001). Significance: The presence of microcracks within the superficial enamel in proximal contact areas could be determined using SS-OCT, and correlated with the level of demineralization. 3D SS-OCT is a valuable diagnostic tool for comprehensive assessment of microstructural changes related to enamel demineralization and crack development.
AB - Objective: The purpose of this study was to detect and investigate the association of enamel microcracks with demineralization at proximal contact areas of premolars, using 3D swept-source optical coherence tomography (SS-OCT). Methods: Extracted maxillary and mandibular premolars (n = 50 each), without any visible tooth cracks, were examined for demineralization of interproximal contact areas, using the International Caries Detection and Assessment System (ICDAS). SS-OCT was used to evaluate demineralization and detect microcracks. Demineralization progression was divided into 4 types by depth: 0 for sound enamel and Type I, II, and III for enamel demineralization penetrating into the outer third, the middle third, and the inner third of the enamel thickness, respectively. Enamel microcracks were classified according to the predominant crack pattern: Type O, no cracks; Type A, subsurface microdefects; Type B, enamel microcrack running along the direction of the enamel prism; Type C, enamel microcrack running transverse to the enamel prism direction; and Type D, a combination of patterns A, B, and C. SS-OCT findings were confirmed by confocal laser scanning microscopy observation. Results: Microcracks confined within the superficial enamel in proximal contact areas were seen as bright lines on SS-OCT. There were significant positive correlations among ICDAS codes, demineralization levels, and microcrack distribution (p ≤ 0.001). The mesial side of maxillary premolars showed significantly more demineralization (n = 36) and microcracks (n = 27) than that of the mandibular premolars (n = 20 and n = 14, respectively; p < 0.001). Significance: The presence of microcracks within the superficial enamel in proximal contact areas could be determined using SS-OCT, and correlated with the level of demineralization. 3D SS-OCT is a valuable diagnostic tool for comprehensive assessment of microstructural changes related to enamel demineralization and crack development.
KW - 3D imaging
KW - Demineralization
KW - Enamel
KW - International Caries Detection and Assessment System (ICDAS)
KW - Microcrack
KW - Optical coherence tomography
KW - Proximal contact
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U2 - 10.1016/j.dental.2019.01.008
DO - 10.1016/j.dental.2019.01.008
M3 - Article
C2 - 30770133
AN - SCOPUS:85061338654
SN - 0109-5641
VL - 35
SP - e74-e82
JO - Dental Materials
JF - Dental Materials
IS - 4
ER -