Evaluation of caries-affected dentin with optical coherence tomography.
The purpose of this study was to evaluate the degree of demineralization of artificially induced caries-affected human dentin by an in vitro microbiological method. The occlusal surfaces of 6 human molar teeth were abraded until a flat surface was obtained, and the enamel was removed to expose the occlusal dentin surface. These teeth were sectioned in 12 halves in the vestibular-lingual direction and divided into 3 groups according to the period length of the microbiological essay (n = 4): G1, 7 days; G2, 14 days; and G3, 21 days. The surfaces of all specimens were protected by an acid-resistant nail varnish, except for a window where the caries lesion was induced by a Streptoccocus mutans biofilm in a batch-culture model supplemented with 5% sucrose. The specimens were then analyzed by optical coherence tomography (OCT) with a super-luminescent light diode (Λ = 930 nm) with 6.0-µm lateral and longitudinal resolution (in the air). Qualitative and quantitative results (images and average dentin demineralization, respectively) were obtained. The mean demineralization depths were (µm) 235 ± 31.4, 279 ± 14, and 271 ± 8.3 in groups 1, 2, and 3, respectively. In addition, no significant change was observed in the lesion mean depth from 7 days of cariogenic challenge on. In conclusion, OCT was shown to be an efficient and non-invasive method to detect the depths of lesions caused by demineralization. Further, a seven-day demineralization time was considered sufficient for caries-affected dentin to be obtained.
Department of Operative Dentistry, Dental School, University of São Paulo, São Paulo, SP, Brazil.
Cynthia Soares de
CS
Azevedo
Luciana Cardoso Espejo
LC
Trung
Maria Regina Lorenzetti
MR
Simionato
Anderson Zanardi de
AZ
Freitas
Adriana Bona
AB
Matos
D018441:Biofilms; D003731:Dental Caries / Q000175:diagnosis*; D003732:Dental Caries Activity Tests / Q000379:methods*; D003804:Dentin / Q000737:chemistry / Q000648:ultrastructure*; D006801:Humans; D066298:In Vitro Techniques; D013499:Surface Properties; D013997:Time Factors; D041623:Tomography, Optical Coherence / Q000379:methods*