1. Articles in category: Dentistry

    1-24 of 337 1 2 3 4 ... 12 13 14 »
    1. Internal fit of pressed and computer-aided design/computer-aided manufacturing ceramic crowns made from digital and conventional impressions

      Internal fit of pressed and computer-aided design/computer-aided manufacturing ceramic crowns made from digital and conventional impressions

      Statement of problem No studies have evaluated the internal adaptation of pressed and milled ceramic crowns made from digital impressions. Purpose The purpose of this in vitro study was to evaluate the internal fit of pressed and milled ceramic crowns made from digital and conventional impressions. Material and methods Thirty polyvinyl siloxane (PVS) impressions and 30 Lava COS impressions made of a prepared dentoform tooth (master die) were fabricated. Thirty crowns were pressed in lithium disilicate (IPS e.max Press), and 30 crowns were milled from lithium disilicate blocks (IPS e.max CAD) (15/impression technique) with the E4D scanner ...

      Read Full Article
    2. Clinical assessment of non carious cervical lesion using swept-source optical coherence tomography

      Clinical assessment of non carious cervical lesion using swept-source optical coherence tomography

      ( A ) We determined the attenuation coeffcient (μ t ) threshold of SS-OCT signal for the detection of demineralization (1.21) from in vitro study. DEM: demineralized dentin, sound: sound dentin. ( B ) Using the μ t threshold, we observed NCCLs in vivo to detect the demineralization in cervical dentin. SS-OCT scanning was performed along the red line. ( C ) SS-OCT image obtained along the red line in B. In SS-OCT, brightness of dentin beneath the NCCL was increased (arrow) compared with intact zone. The cervical dentin was slightly demineralized (μ t : 1.25). e: enamel, d: dentin, g: gingiva. Non-carious cervical lesions (NCCLs) involve various forms ...

      Read Full Article
    3. Development of an electro-optically tuned optical coherence tomography system for imaging dental lesions

      Development of an electro-optically tuned optical coherence tomography system for imaging dental lesions

      A conventional optical coherence tomography (OCT) system was set up in-house to image early dental caries, identify gap formation in the bonding interface for restoration and secondary caries. Two-dimensional images of tooth samples was obtained and dental defect were identified. A novel electro-optic tuning system is proposed in order to improve scanning speed and to perform noiseless imaging. Preliminary studies were conducted with two crystals namely, LiNbO 3 (Lithium Niobate) and KTP (Potassium Titanyl Phosphate) using a SLED source for OCT system and the simulated and experimental results were found to be qualitatively similar. The tuning range for LiNbO 3 ...

      Read Full Article
    4. Assessment of the sealant/tooth interface using optical coherence tomography

      Assessment of the sealant/tooth interface using optical coherence tomography

      Sealant materials are typically employed in dentistry in order to prevent the development of cavities on the teeth. They prevent bacterial adhesion to enamel, thus arresting the development of demineralization and of caries. In this study, the critical zone of the interface between different sealant materials and the results of the dental work for the teeth processed were investigated ex vivo using swept source (SS) optical coherence tomography (OCT). Optical inspection and X-ray investigation revealed no defects, while SS-OCT proved capable to asses exactly the position, the nature, and the dimensions of each type of these defects. Specifically, different failures ...

      Read Full Article
    5. Optical Coherence Tomography: A new era in dentistry

      Optical Coherence Tomography: A new era in dentistry

      Dental prostheses are very complex systems, heterogenous in structure, made up from various materials, with different physical properties. They have to satisfy high stress requirements as well as aesthetic challenges. The failures of dental prostheses lead to functional, aesthetic and phonetic disturbances which finally render the prosthetic treatment inefficient. OCT is a tomography imaging technology capable of producing high-resolution cross-sectional images of the internal architecture of materials and tissues. This includes not only the images of normal and abnormal dental hard tissue structures but also teeth after several treatment methods. It can be used for non-invasive investigations for both in-vivo ...

      Read Full Article
    6. High contrast imaging of early demineralization on enamel surfaces using near-infrared polarized reflectance at lambda= 1460 and 1550 nm (Thesis)

      High contrast imaging of early demineralization on enamel surfaces using near-infrared polarized reflectance at lambda= 1460 and 1550 nm (Thesis)

      Introduction: In vivo and in vitro studies have shown that high contrast images of tooth demineralization can be acquired in the near-infrared at several wavelengths. The purpose of this study is to compare the lesion contrast in reflectance at near-infrared wavelengths coincident with high water absorption with those in the visible, the near-infrared at 1300nm, fluorescence, and polarization sensitive optical coherence tomography (PS-OCT) measurements for early lesions on buccal surfaces. Methods: Bovine incisors (n=40) were used in this in vitro study. Teeth were sectioned so that they were greater than 8mm in length, 2mm in width, and had at ...

      Read Full Article
      Mentions: UCSF
    7. Evaluation of the effects of fluoride-releasing varnish on dentin demineralization using optical coherence tomography

      Evaluation of the effects of fluoride-releasing varnish on dentin demineralization using optical coherence tomography

      Effects of a fluoride-releasing varnish containing surface reaction-type prereacted glass ionomer (S-PRG) filler on dentin demineralization were examined using optical coherence tomography. Bovine incisors that were sliced and treated with undersaturated 0.1 M lactic acid buffer solution (DE group). A thin film of varnish-containing S-PRG filler was applied before demineralization (PRG group). Control was maintained in artificial saliva. Using optical coherence tomography of selected locations on the dentin surface, peak intensity (dB) and width (μm) at 1/e 2 were obtained and integrated values calculated. Although alterations in integrated values were different in each group, there was a slight ...

      Read Full Article
    8. Detection of a Second Mesiobuccal Canal in Maxillary Molars by Swept-source Optical Coherence Tomography

      Detection of a Second Mesiobuccal Canal in Maxillary Molars by Swept-source Optical Coherence Tomography

      Introduction The purpose of this study was to investigate the ability of swept-source optical coherence tomographic (SS-OCT) imaging to detect a second mesiobuccal canal (MB2) in maxillary molars compared with visual inspection (VI) and dental operating microscopy (DOM). Methods Forty extracted human maxillary molars were examined. After the removal of half the crown and access cavity preparation, the existence of MB2 canals was confirmed based on cross-sectional images of each tooth obtained by micro–computed tomographic scanning as the reference standard. Then, the pulp chamber floor was scanned by SS-OCT imaging. Three dentists independently evaluated the SS-OCT images and the ...

      Read Full Article
    9. Evaluation of two quantitative analysis methods of optical coherence tomography for detection of enamel demineralization and comparison with microhardness

      Evaluation of two quantitative analysis methods of optical coherence tomography for detection of enamel demineralization and comparison with microhardness

      Background and Objective We aimed to evaluate in the same study two quantitative methods for quantification of incipient caries in human dental enamel by using optical coherence tomography (OCT): the optical attenuation coefficient and the area under the A-scan signal, and to compare their results with those obtained from microhardness analysis. Study Design/Materials and Methods One hundred and sixty samples were obtained from 40 sound human third molars, which had their crowns sectioned. Simulated caries were created by a pH cycling method. OCT measurements were performed on the samples, before and after the induced demineralization. We determined the total ...

      Read Full Article
    10. Comparing the In Vivo Diagnostic Accuracy of Digital Periapical Radiography with Cone-beam Computed Tomography for the Detection of Vertical Root Fracture

      Comparing the In Vivo Diagnostic Accuracy of Digital Periapical Radiography with Cone-beam Computed Tomography for the Detection of Vertical Root Fracture

      Introduction The purpose of this study was to determine whether there is a difference in the in vivo diagnostic accuracy of digital radiography (DR) and cone-beam computed tomography (CBCT) imaging in the detection of vertical root fracture (VRF). The presence/absence of VRF was confirmed by visual inspection of the extracted root surface and was the reference standard against which both imaging modalities were compared. Methods Twenty-one unsalvageable teeth from 20 patients that had been radiographed and scanned with CBCT imaging were included in the study. The teeth were atraumatically extracted and visually inspected under a microscope to confirm the ...

      Read Full Article
    11. A method for monitoring enamel erosion using laser irradiated surfaces and optical coherence tomography

      A method for monitoring enamel erosion using laser irradiated surfaces and optical coherence tomography

      Introduction Since optical coherence tomography (OCT) is well suited for measuring small dimensional changes on tooth surfaces, OCT has great potential for monitoring tooth erosion. Previous studies have shown that enamel areas ablated by a carbon dioxide laser manifested lower rates of erosion compared to the non-ablated areas. The purpose of this study was to develop a model to monitor erosion in vitro that could potentially be used in vivo . Methods Thirteen bovine enamel blocks were used in this in vitro study. Each 10 mm × 2 mm block was partitioned into five regions, the central region was unprotected, the adjacent ...

      Read Full Article
    12. UCSF received a NIH Grant for Clinical Assessment of Tooth Demineralization & Remineralization with PS-OCT

      UCSF received a NIH Grant for Clinical Assessment of Tooth Demineralization & Remineralization with PS-OCT

      University of California at San Francisco received a 2014 NIH Grant for $333,825 for Clinical Assessment of Tooth Demineralization & Remineralization with PS-OCT. The principal investigator is Daniel Fried. The program began in 2006 and ends in 2015. Below is a summary of the proposed work. The overall objective of this proposed research is to develop polarization sensitive optical coherence tomography (PS-OCT) as a non-invasive optical device for the accurate and early clinical assessment of tooth demineralization and remineralization. The central hypothesis underlying this proposal is that the depth-resolved changes in the magnitude of light scattering of dental hard tissues ...

      Read Full Article
    13. Design and testing of prototype handheld scanning probes for optical coherence tomography

      Design and testing of prototype handheld scanning probes for optical coherence tomography

      Three simple and low-cost configurations of handheld scanning probes for optical coherence tomography have been developed. Their design and testing for dentistry applications are presented. The first two configurations were built exclusively from available off-the-shelf optomechanical components, which, to the best of our knowledge, are the first designs of this type. The third configuration includes these components in an optimized and ergonomic probe. All the designs are presented in detail to allow for their duplication in any laboratory with a minimum effort, for applications that range from educational to high-end clinical investigations. Requirements that have to be fulfilled to achieve ...

      Read Full Article
    14. Automated assessment of the remineralization of artificial enamel lesions with polarization-sensitive optical coherence tomography

      Automated assessment of the remineralization of artificial enamel lesions with polarization-sensitive optical coherence tomography

      Accurate measurement of the highly mineralized transparent surface layer that forms on caries lesions is important for diagnosis of the lesion activity because chemical intervention can slow or reverse the caries process via remineralization. Previous in-vitro and in-vivo studies have demonstrated that polarization-sensitive optical coherence tomography (PS-OCT) can nondestructively image the subsurface lesion structure and the highly mineralized transparent surface zone of caries lesions. The purpose of this study was to develop an approach to automatically process 3-dimensional PS-OCT images and to accurately assess the remineralization process in simulated enamel lesions. Artificial enamel lesions were prepared on twenty bovine enamel ...

      Read Full Article
    15. Viewing Dentistry in a New Light

      Viewing Dentistry in a New Light

      Dental X-rays expose patients to radiation, require time to process, and can only “see” a limited amount inside the mouth. Now new optical techniques developed by UC San Francisco’s Daniel Fried , PhD, use light to take instantaneous digital images that can provide a better picture of our teeth and could one day zap cavities with pinpoint precision. Daniel Fried, PhD, speaks with Leon Chung, a dental research fellow in his lab. Photo by Susan Merrell Fried, a professor in the School of Dentistry’s Division of Biomaterials and Bioengineering in the Department of Preventive and Restorative Dental Sciences, is ...

      Read Full Article
    16. Optical Coherence Tomography & Dentistry

      Optical Coherence Tomography & Dentistry

      In dentistry, optical coherence tomography (OCT), a type of digital imaging, is used to support patient diagnosis, treatment planning, and education. Providing a localized image in a real-time setting, this technique can be used to detect caries, support the diagnosis of periodontal diseases, indicate tooth fractures, evaluate the margins of oral lesions, and measure cavity preparations for restorations created by computer-aided design/computer-aided manufacturing (CAD/CAM) technology. OCT was developed into a cross-sectional imaging modality in medicine by Huang et al 1 in 1991. The imaging technique was first applied in ophthalmology with a focus on the retina, optic nerve ...

      Read Full Article
    17. Effectiveness of varnish with CPP–ACP in prevention of caries lesions around orthodontic brackets: an OCT evaluation

      Effectiveness of varnish with CPP–ACP in prevention of caries lesions around orthodontic brackets: an OCT evaluation

      Objective: To evaluate the in vitro efficiency of applying varnish containing casein phosphopeptide (CPP) and amorphous calcium phosphate (ACP) in prevention of caries lesions around orthodontic brackets. Materials and methods: For this purpose, brackets were bonded to the vestibular surface of bovine incisors, and eight groups were formed ( n = 15) according to exposure of oral hygiene substances and enamel varnish: 1 (control) brushing only performed, 2 (control) brushing + use of mouth wash with fluoride, 3 Duraphat varnish application only (Colgate-Palmolive Ind. E Com. Ltda, São Paulo, SP, Brazil), 4 Duraphat + brushing, 5 Duraphat + brushing + mouth wash, 6 MI Varnish ...

      Read Full Article
    18. PhD position in Dental Optical Coherence Tomography Department of Odontology at University of Copenhagen.

      PhD position in Dental Optical Coherence Tomography Department of Odontology at University of Copenhagen.

      PhD fellowship in dental optical coherence tomography - Department of Odontology Applications are invited for a PhD Fellowship at the Department of Odontology, Faculty of Health and Medical Sciences, University of Copenhagen. The candidate will work in the area of digital dental scanning with focus on optical coherence tomography (OCT). The position is for a 3-year period and will commence on 1 September 2014 or as soon as possible thereafter. Project description The project is part of a research programme between industry, Technical University of Denmark (DTU) and Department of Odontology, University of Copenhagen. The objective of the project is to ...

      Read Full Article
    19. Material Defects in Ceramic Crowns Identification by Optical Coherence Tomography and MicroCT

      Material Defects in Ceramic Crowns Identification by Optical Coherence Tomography and MicroCT

      Full ceramic crowns are considered revolutionary in developing the concept of aesthetic dentistry. Appreciate their aesthetic appearance particularly raise the cost prices, they do not ensure the risk of fractures and cracks which sometimes face the clinician after their insertion directly into the mouth. As a result of the fracture may occur between disputes team dentist-dental technician. The purpose of this study was to identify flaws of material included in the pottery table analyzing the full ceramic crowns using non-invasive technologies. As materials we use 25 full ceramic crowns (e. max, IVOCLAR) obtained through the technology of pressing were used ...

      Read Full Article
    20. Examination of ceramic/enamel interfacial debonding using acoustic emission and optical coherence tomography

      Examination of ceramic/enamel interfacial debonding using acoustic emission and optical coherence tomography

      Objective This study investigates monitored micro-crack growth and damage in the ceramic/enamel adhesive interface using the acoustic emission (AE) technique with optical coherence tomography (OCT) under fatigue shear testing. Methods Shear bond strength (SBS) was measured first with eight prepared ceramic/enamel adhesive specimens under static loads. The fatigue shear testing was performed with three specimens at each cyclic load according to a modified ISO14801 method, applying at 80%, 75%, 70%, and 65% of the SBS to monitor interface debonding. The number of cycles at each load was recorded until ceramic/enamel adhesive interface debonding occurred. The AE technique ...

      Read Full Article
    21. Sealing performance of resin cements before and after thermal cycling: Evaluation by optical coherence tomography

      Sealing performance of resin cements before and after thermal cycling: Evaluation by optical coherence tomography

      Objectives Self-adhesive resin cements have been recently introduced; however, there is little data available on their long-term performance. In this in vitro study, swept-source optical coherence tomography (OCT) at 1310 nm center wavelength was used for monitoring adaptation of indirect resin restorations after thermal cycling. Methods Resin inlays were luted to class-I cavities of extracted human teeth using three resin cements; Clearfil SA Luting (SA; Kuraray), Bistite II DC or Multibond II (Tokuyama Dental). Each cement was applied with or without pre-coating of dentin by a self-etch adhesive (Clearfil SE Bond) and a low-viscosity microfilled resin. OCT imaging was performed ...

      Read Full Article
    22. Application of Optical Coherence Tomography to Identify Pulp Exposure During Access Cavity Preparation Using an Er:YAG Laser

      Application of Optical Coherence Tomography to Identify Pulp Exposure During Access Cavity Preparation Using an Er:YAG Laser

      Objective : The study aimed to evaluate the ability of optical coherence tomography (OCT) to guide and identify pulp exposure using an erbium: yttrium–aluminum–garnet (Er:YAG) laser. Background data: The Er:YAG laser has been proven to be effective in ablating dental hard tissue and offers advantages, as there is none of the vibration and noise you get with conventional methods, but it has limitations in relation to the tactile feedback that would aid in identification of entry into the pulp chamber. Based on depth-resolved optical reflectivity, OCT technology has been developed to provide high-resolution, cross-sectional images of the ...

      Read Full Article
    23. Attenuation of near-IR light through dentin at wavelengths from 1300-1650-nm

      Attenuation of near-IR light through dentin at wavelengths from 1300-1650-nm

      Light scattering in dental enamel decreases markedly from the UV to the near-IR and recent studies employing near-IR transillumination and reflectance imaging including optical coherence tomography indicate that this wavelength region is ideally suited for imaging dental caries due to the high transparency of enamel. The opacity of dentin is an important factor in optimizing the contrast of demineralization in reflectance measurements. It also influences the contrast of occlusal lesions in transillumination. Light scattering in dentin is an order of magnitude larger than in enamel, it is highly anisotropic and has a different spectral light scattering dependence than enamel. The ...

      Read Full Article
    1-24 of 337 1 2 3 4 ... 12 13 14 »
  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. (1 articles) Boston University
    2. (1 articles) Tokyo Medical & Dental University
    3. (1 articles) National Center for Geriatrics and Gerontology in Japan
    4. (1 articles) University of Iowa
  4. People in the News

    1. (1 articles) Junji Tagami
    2. (1 articles) Yasushi Shimada
    3. (1 articles) Alireza Sadr
    4. (1 articles) Yasunori Sumi
    5. (1 articles) Syozi Nakashima