1. Articles in category: Dentistry

    1-24 of 427 1 2 3 4 ... 16 17 18 »
    1. Imaging Resin Infiltration into Non-Cavitated Carious Lesions by Optical Coherence Tomography

      Imaging Resin Infiltration into Non-Cavitated Carious Lesions by Optical Coherence Tomography

      Objectives Visualisation of the etching process and resin penetration at white spot carious lesions by spectral domain optical coherence tomography (SD-OCT). Materials and methods The non-cavitated carious lesions (ICDAS code 2) of four visually preselected extracted human molars and premolars were verified as enamel lesions by micro computed tomography (μCT). One region of interest (ROI) per tooth was marked by two drill-holes in occlusal-cervical direction. The lesions were imaged by SD-OCT. Lesions were infiltrated (Icon, DMG) according to the manufacturer’s instructions. During each treatment step and after light curing of the infiltrant, the ROIs were imaged again by SD-OCT ...

      Read Full Article
    2. Automatic detection of tooth cracks in optical coherence tomography images

      Automatic detection of tooth cracks in optical coherence tomography images

      Purpose The aims of the present study were to compare the image quality and visibility of tooth cracks between conventional methods and swept-source optical coherence tomography (SS-OCT) and to develop an automatic detection technique for tooth cracks by SS-OCT imaging. Methods We evaluated SS-OCT with a near-infrared wavelength centered at 1,310 nm over a spectral bandwidth of 100 nm at a rate of 50 kHz as a new diagnostic tool for the detection of tooth cracks. The reliability of the SS-OCT images was verified by comparing the crack lines with those detected using conventional methods. After performing preprocessing of ...

      Read Full Article
    3. Improved accuracy in periodontal pocket depth measurement using optical coherence tomography

      Improved accuracy in periodontal pocket depth measurement using optical coherence tomography

      Purpose The purpose of this study was to examine whether periodontal pocket could be satisfactorily visualized by optical coherence tomography (OCT) and to suggest quantitative methods for measuring periodontal pocket depth. Methods We acquired OCT images of periodontal pockets in a porcine model and determined the actual axial resolution for measuring the exact periodontal pocket depth using a calibration method. Quantitative measurements of periodontal pockets were performed by real axial resolution and compared with the results from manual periodontal probing. Results The average periodontal pocket depth measured by OCT was 3.10±0.15 mm, 4.11±0.17 mm ...

      Read Full Article
    4. Evaluation of dermal fillers with noncontact optical coherence elastography

      Evaluation of dermal fillers with noncontact optical coherence elastography

      Over 2 million dermal filler procedures are performed each year in the USA alone, and this figure is only expected to increase as the aging population continues to grow. Dermal filler treatments can last from a few months to years depending on the type of filler and its placement. Although adverse reactions are rare, they can be quite severe due to ischemic events and filler migration. Previously, techniques such as ultrasound or magnetic resonance imaging have been used to evaluate the filler injections. However, these techniques are not practical for real-time filler injection guidance due to limitations such as the ...

      Read Full Article
    5. Study on application to the field of dentistry using optical coherence tomography (OCT)

      Study on application to the field of dentistry using optical coherence tomography (OCT)

      Purpose This paper describes the basic principles and the feasibility of the field of dental diagnosis of optical coherence tomography (OCT) used in diverse field of medical diagnosis. Materials and methods In this review, the research data of OCT were searched from PubMed, medical journal and related papers. Results Generally, OCT is non-invasive and is possible to secure an excellent spatial resolution and real-time images of biological microstructure. Conclusion This review discusses not only the basic principles of operation, types, advantages, disadvantages of OCT but also the future applications of OCT technology and their potential in the field of dental ...

      Read Full Article
    6. Enamel Thickness before and after Orthodontic Treatment Analysed in Optical Coherence Tomography

      Enamel Thickness before and after Orthodontic Treatment Analysed in Optical Coherence Tomography

      Despite the continuous development of materials and techniques of adhesive bonding, the basic procedure remains relatively constant. The technique is based on three components: etching substance, adhesive system, and composite material. The use of etchants during bonding orthodontic brackets carries the risk of damage to the enamel. Therefore, the article examines the effect of the manner of enamel etching on its thickness before and after orthodontic treatment. The study was carried out in vitro on a group of 80 teeth. It was divided into two subgroups of 40 teeth each. The procedure of enamel etching was performed under laboratory conditions ...

      Read Full Article
    7. Assessing the dynamic biofilm removal of sulfonated phenolics using CP-OCT

      Assessing the dynamic biofilm removal of sulfonated phenolics using CP-OCT

      Examining the physical mechanisms related to biofilm removal of sulfonated phenolics (SP) is difficult using conventional microscopy techniques. A custom flow cell system integrated with a real time cross polarization optical coherence tomography system investigated the dynamic speed of biofilm removal when oral multi-species biofilms are exposed to SP under sheer stress. The Near infrared 1310-nm CP-OCT system non-destructively imaged fluid immersed oral biofilms at nearly 30 frames/s. This dynamic imaging was able to determine the cohesive and adhesion related disruption of SP on oral biofilms adhering to tooth like surfaces. For multi-species biofilms that are initially grown without ...

      Read Full Article
    8. Characterization of human oral tissues based on quantitative analysis of optical coherence tomography images

      Characterization of human oral tissues based on quantitative analysis of optical coherence tomography images

      In this paper, five types of tissues, human enamel, human cortical bone, human trabecular bone, muscular tissue, and fatty tissue were imaged ex vivo using optical coherence tomography (OCT). The specimens were prepared in blocks of 5 x 5 x 3 mm (width x length x height). The OCT imaging system was a swept source OCT system operating at wavelengths ranging between 1250 nm and 1360 nm with an average power of 18 mW and a scan rate of 50 to 100 kHz. The imaging probe was placed on top of a 2 x 2 cm stabilizing device to maintain ...

      Read Full Article
    9. Resolution characteristics of optical coherence tomography for dental use

      Resolution characteristics of optical coherence tomography for dental use

      OBJECTIVES: The purpose of this study was to clarify resolution characteristics of optical coherence tomography (OCT) for dental use. METHODS: Two types of swept-source OCT machines (SS-OCTs) were employed in this study. To clarify their resolution characteristics, we newly developed a glass chart device with a ladder pattern of wavelengths, which ranged from (4 x 2) µm to (1024 x 2) µm, as well as a star-target pattern, a grid pattern, and a spatial frequency response pattern. The resolving powers and characteristics of the OCTs were subjectively evaluated. RESULTS: The Santec OCT had a resolving power of 64 µm in ...

      Read Full Article
    10. Optical Coherence Technology Detects Early Signs of Peri-implant Mucositis in the Minipig Model

      Optical Coherence Technology Detects Early Signs of Peri-implant Mucositis in the Minipig Model

      Background: Peri-implant mucositis defines the inflammation of gingival tissue surrounding osseous integrated implants without destruction of supporting bone. Untreated mucositis may develop into peri-implantitis with irreversible resorption of alveolar bone and implant failure. Mucositis is reversible with early intervention; however, existing clinical approaches have proved inadequate to reveal initial stages of this complication. Optical Coherence Tomography (OCT) is a non-invasive modality that provides real time, cross-sectional optical images of tissue up to 2-3mm in depth from the surface. Here, the minipig model assessed the diagnostic capability of OCT to detect early signs of mucositis by imaging microstructural changes of soft ...

      Read Full Article
    11. Optical coherence tomography for early detection of dental diseases: In vitro and in vivo feasibility studies ( Thesis)

      Optical coherence tomography for early detection of dental diseases: In vitro and in vivo feasibility studies ( Thesis)

      nflammation of the gums and tooth decay are conditions that, if detected early enough, can be corrected or reversed. There is therefore a need for minimally invasive, accurate assessment of dental and periodontal tissue in order to achieve prompt diagnosis and treatment. Optical coherence tomography (OCT) is an emerging non-invasive, non-ionizing imaging modality that provides cross-sectional images of tissue, up to several millimeters in depth with micrometer level resolution. The underlying hypothesis of this thesis is that biological alterations to oral tissues result in changes in light scattering behavior which could be quantified by OCT. In vitro bovine tooth samples ...

      Read Full Article
    12. A pilot study to assess the morphology and progression of non-carious cervical lesions

      A pilot study to assess the morphology and progression of non-carious cervical lesions

      Objective This longitudinal pilot study aimed to morphologically and quantitatively investigate the progress of non-carious cervical lesions (NCCLs) by using swept-source optical coherence tomography (SS-OCT). Methods The samples examined comprised sets of NCCL epoxy resin replicas obtained from 10 lesions in 6 patients who attended annual dental visits over 4 or 5 years. SS-OCT images of the replicas were analyzed in terms of the maximum depth (D max ) and corresponding vertical width (VW) − using an image analyzer to estimate progression of the NCCLs over time. Results It was found that differences between wedge- and saucer-shaped lesions were morphologically distinguished well ...

      Read Full Article
    13. Bio-Photonic Detection and Quantitative Evaluation Method for the Progression of Dental Caries Using Optical Frequency-Domain Imaging Method

      Bio-Photonic Detection and Quantitative Evaluation Method for the Progression of Dental Caries Using Optical Frequency-Domain Imaging Method

      The initial detection of dental caries is an essential biomedical requirement to barricade the progression of caries and tooth demineralization. The objective of this study is to introduce an optical frequency-domain imaging technique based quantitative evaluation method to calculate the volume and thickness of enamel residual, and a quantification method was developed to evaluate the total intensity fluctuation in depth direction owing to carious lesions, which can be favorable to identify the progression of dental caries in advance. The cross-sectional images of the ex vivo tooth samples were acquired using 1.3 μm spectral domain optical coherence tomography system (SD-OCT ...

      Read Full Article
    14. Three-Dimensional Analysis of Enamel Crack Behavior Using Optical Coherence Tomography

      Three-Dimensional Analysis of Enamel Crack Behavior Using Optical Coherence Tomography

      The aim of this study was to nondestructively analyze enamel crack behavior on different areas of teeth using 3D swept source-optical coherence tomography (SS-OCT). Ten freshly extracted human teeth of each type on each arch ( n = 80 teeth) were inspected for enamel crack patterns on functional, contact and nonfunctional, or noncontact areas using 3D SS-OCT. The predominant crack pattern for each location on each specimen was noted and analyzed. The OCT observations were validated by direct observations of sectioned specimens under confocal laser scanning microscopy (CLSM). Cracks appeared as bright lines with SS-OCT, with 3 crack patterns identified: Type I ...

      Read Full Article
    15. Optical analysis of enamel and dentin caries in relation to mineral density using swept-source optical coherence tomography

      Optical analysis of enamel and dentin caries in relation to mineral density using swept-source optical coherence tomography

      The aim of this study was to evaluate the signal intensity and signal attenuation of swept source optical coherence tomography (SS-OCT) for dental caries in relation to the variation of mineral density. SS-OCT observation was performed on the enamel and dentin artificial demineralization and on natural caries. The artificial caries model on enamel and dentin surfaces was created using Streptococcus mutans biofilms incubated in an oral biofilm reactor. The lesions were centrally cross sectioned and SS-OCT scans were obtained in two directions to construct a three-dimensional data set, from the lesion surface (sagittal scan) and parallel to the lesion surface ...

      Read Full Article
    16. Method and apparatus for measuring and displaying dental plaque

      Method and apparatus for measuring and displaying dental plaque

      A method and an apparatus for measuring and displaying dental plaque are provided, and the method includes the steps of dividing near infrared light output from a light source into measurement light and reference light, applying the measurement light toward a tooth in an oral cavity and scanning the tooth with the measurement light, producing interference light from reflected light and back-scattered light from the tooth and the reference light, generating an optical coherence tomographic image based on a scattering intensity value of the interference light, extracting a dental plaque region having a specific scattering intensity value from the optical ...

      Read Full Article
    17. Progression of erosive lesions after Nd:YAG laser and fluoride using optical coherence tomography

      Progression of erosive lesions after Nd:YAG laser and fluoride using optical coherence tomography

      This study aimed to use optical coherence tomography (OCT) to assess the progression of erosive lesions after irradiation with Nd:YAG laser and application of topical fluoride. One-hundred and twenty dentin samples (4 × 4 × 2 mm) obtained from bovine incisors were used. Samples were protected with acid-resistant nail varnish, with exception of a central circular area 2 mm in diameter. All samples were submitted to erosive cycles with citric acid solution 0.05 M (citric acid monohydrate—C6H8O7·H2O); M = 210.14 g/mol) pH 2.3, at room temperature, for 20 min, 2×/day, throughout 20 days. After 10 ...

      Read Full Article
    18. Comparison of the marginal adaptation of direct and indirect composite inlay restorations with optical coherence tomography

      Comparison of the marginal adaptation of direct and indirect composite inlay restorations with optical coherence tomography

      Objective The purpose of the study was to use the photonic imaging modality of optical coherence tomography (OCT) to compare the marginal adaptation of composite inlays fabricated by direct and indirect techniques. Material and Methods Class II cavities were prepared on 34 extracted human molar teeth. The cavities were randomly divided into two groups according to the inlay fabrication technique. The first group was directly restored on cavities with a composite (Esthet X HD, Dentsply, Germany) after isolating. The second group was indirectly restored with the same composite material. Marginal adaptations were scanned before cementation with an invisible infrared light ...

      Read Full Article
      Mentions: Thorlabs
    19. In vivo assessment of periodontal structures and measurement of gingival sulcus with Optical Coherence Tomography: a pilot study

      In vivo assessment of periodontal structures and measurement of gingival sulcus with Optical Coherence Tomography: a pilot study

      There has been increasing interest on the development of clinically acceptable, more sensitive and specific methods for non-invasive diagnosis in Periodontics. In this pilot study, the performance of an Optical Coherence Tomography (OCT) system in imaging periodontal structures in humans was evaluated. Gingival sulcus depth measurements were obtained and compared with traditional probes. In total, 445 sites of 23 periodontally healthy individuals were measured by 3 instruments: North Carolina manual probe, Florida automated probe and OCT at 1325 nm. To obtain quantitative measurements from OCT images, the gingival refractive index was also determined. Discomfort/pain perception and the duration of ...

      Read Full Article
    20. Enamel Thickness Determination by Optical Coherence Tomography: In vitro Validation

      Enamel Thickness Determination by Optical Coherence Tomography: In vitro Validation

      Optical coherence tomography (OCT) has been introduced in dentistry as a nondestructive diagnostic imaging tool that does not utilize ionizing radiation. This study investigated the agreement between polarization-sensitive OCT (PS-OCT), microcomputed tomography (μ-CT), and histology for enamel thickness measurements. Human enamel samples were prepared and evaluated with μ-CT and PS-OCT and then sectioned and observed via digital transversal light microscopy. For all methods, a standard transversal section (b-scan) in each sample was selected, and the enamel thickness was measured at three predetermined positions using ImageJ analysis software. The results revealed significant high agreement between all tested methods, indicating the potential ...

      Read Full Article
    21. Assessment of bacterial demineralization around composite restorations using swept-source optical coherence tomography (SS-OCT)

      Assessment of bacterial demineralization around composite restorations using swept-source optical coherence tomography (SS-OCT)

      Objective To observe the bacterial demineralization of the enamel and dentin around composite restorations bonded with one-step and two-step self-etch adhesive systems using swept-source optical coherence tomography (SS-OCT). Methods Forty class V cavities (2.5-mm surface diameter, 2.0-mm maximum depth) were prepared on cervical areas of 20 human molars. The specimens were either treated with one-step adhesive (Clearfil Tri-S Bond ND Quick; TS) or two-step adhesive (Clearfil SE Bond; SE), restored with a flowable resin composite (Estelite Flow Quick). Specimens in the demineralized group were incubated for 2 weeks after Streptococcus mutans biofilm formation, while specimens in the control ...

      Read Full Article
    22. Monitoring of cariogenic demineralization at the enamel–composite interface using swept-source optical coherence tomography

      Monitoring of cariogenic demineralization at the enamel–composite interface using swept-source optical coherence tomography

      Objectives The aim of this study was to evaluate enamel demineralization at composite restoration margins caused by cariogenic biofilm using swept-source optical coherence tomography (SS-OCT). Methods Sixty round-shaped cavities were prepared on the mid-buccal enamel surface of extracted human molars. The cavities were restored with Estelite Flow Quick flowable composite using either Clearfil SE Bond or Clearfil Tri-S Bond ND bonding agents. Streptococcus mutans suspension was applied to form a cariogenic biofilm on the surface. After 1, 2, or 3 weeks of incubation ( n = 10), the biofilm was removed to observe the carious demineralization at the cavosurface margins using SS-OCT ...

      Read Full Article
    23. Internal adaptation of resin composites at two configurations: Influence of polymerization shrinkage and stress

      Internal adaptation of resin composites at two configurations: Influence of polymerization shrinkage and stress

      Objective This study compared internal adaptation of composites under different C-factors and examined the relationship between internal adaptation and polymerization shrinkage parameters. Methods Cylindrical cavities 3 mm in diameter were prepared in 100 human third molars in two depths: 4 mm high C-factor (H-CF) or 1 mm low C-factor (L-CF). After adhesive application (Clearfil SE One, Kuraray Noritake), the composite was placed in two increments in three subgroups: Filtek Supreme (FS, 3 M ESPE); Charisma Diamond (CD, Heraeus Kulzer); Amelogen Plus (AP, Ultradent); and as a single increment in two subgroups: Tetric EvoCeram Bulk Fill (TB, Ivoclar Vivadent) and Venus ...

      Read Full Article
    24. The role of enamel thickness and refractive index on human tooth colour

      The role of enamel thickness and refractive index on human tooth colour

      Objectives To investigate the role of enamel thickness and refractive index ( n ) on tooth colour. Methods The colour and enamel thickness of fifteen extracted human central incisors were determined according to CIELab colour scale using spectrophotometer (Crystaleye) and swept-source optical coherence tomography (SS-OCT), respectively. Subsequently, labial enamel was trimmed by approximately 100 μm, and the colour and remaining enamel thickness were investigated again. This cycle was repeated until dentin appeared. Enamel blocks were prepared from the same teeth and their n were obtained using SS-OCT. Multiple regression analysis was performed to reveal any effects of enamel thickness and n on ...

      Read Full Article
    1-24 of 427 1 2 3 4 ... 16 17 18 »
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks
  2. Popular Articles

  3. Organizations in the News

    1. (2 articles) Seoul National University
    2. (1 articles) University of Houston
    3. (1 articles) Dresden University of Technology
    4. (1 articles) Baylor College of Medicine
  4. People in the News

    1. (1 articles) Robert Koprowski
    2. (1 articles) Manmohan Singh
    3. (1 articles) Kirill V. Larin
    4. (1 articles) Shang Wang
  5. OCT Companies in the News

    1. (1 articles) Topcon Medical Systems