scholarly journals Fluorescence Level of Composites assessed by Computer Processing of Digital Images: ScanWhite©

2012 ◽  
Vol 3 (2) ◽  
pp. 141-144 ◽  
Author(s):  
Marcelo Ferrarezi de Andrade ◽  
José Roberto Cury Saad ◽  
Edson Alves de Campos ◽  
Alessandra Nara de Souza Rastelli ◽  
Mateus Rodrigues Tonetto ◽  
...  
Keyword(s):  
Digital Images ◽  
Uv Light ◽  
Digital Camera ◽  
Computer Processing ◽  
Tooth Structure ◽  
Four Seasons ◽  
Restorative Materials ◽  
Fluorescence Level ◽  
Average Fluorescence

ABSTRACT The human dentition is naturally translucent, opalescent and fluorescent. Differences between the level of fluorescence of tooth structure and restorative materials may result in distinct metameric properties and consequently perceptible disparate esthetic behavior, which impairs the esthetic result of the restorations, frustrating both patients and staff. In this study, we evaluated the level of fluorescence of different composites (Durafill in tones A2 (Du), Charisma in tones A2 (Ch), Venus in tone A2 (Ve), Opallis enamel and dentin in tones A2 (OPD and OPE), Point 4 in tones A2 (P4), Z100 in tones A2 (Z1), Z250 in tones A2 (Z2), Te-Econom in tones A2 (TE), Tetric Ceram in tones A2 (TC), Tetric Ceram N in tones A1, A2, A4 (TN1, TN2, TN4), Four seasons enamel and dentin in tones A2 (and 4SD 4SE), Empress Direct enamel and dentin in tones A2 (EDE and EDD) and Brilliant in tones A2 (Br)). Cylindrical specimens were prepared, coded and photographed in a standardized manner with a Canon EOS digital camera (400 ISO, 2.8 aperture and 1/ 30 speed), in a dark environment under the action of UV light (25 W). The images were analyzed with the software ScanWhite©-DMC/Darwin systems. The results showed statistical differences between the groups (p < 0.05), and between these same groups and the average fluorescence of the dentition of young (18 to 25 years) and adults (40 to 45 years) taken as control. It can be concluded that: Composites Z100, Z250 (3M ESPE) and Point 4 (Kerr) do not match with the fluorescence of human dentition and the fluorescence of the materials was found to be affected by their own tone. How to cite this article Tonetto MR, de Oliveira Junior OB, de Campos EA, Saad JRC, Dantas AAR, de Souza Rastelli AN, de Toledo Porto Neto S, de Andrade MF. Fluorescence Level of Composites assessed by Computer Processing of Digital Images: ScanWhite©. World J Dent 2012;3(2):141-144.

Vital Tooth Whitening Techniques. A literature Review

2020 ◽  
Vol 02 ◽  
Author(s):  
Pia Chatterjee Kirk
Keyword(s):  
Soft Tissues ◽  
Treatment Time ◽  
Tooth Bleaching ◽  
Tooth Whitening ◽  
Easy Method ◽  
Tooth Structure ◽  
Dental Esthetics ◽  
Total Treatment Time ◽  
Restorative Materials ◽  
Total Treatment

Background: Vital tooth whitening has become an integral part of esthetic dentistry and remains one of the safest and most economic options today to improve dental esthetics without removing tooth structure. The tooth whitening materials have evolved into three categories: dentist-prescribed/dispensed (in office and patient home-use), and over-thecounter purchased and applied by patients. Objective: This review outlines the latest advances in dentist prescribed vital teeth whitening techniques, effects on tooth structure, soft tissues, and dental restoratives. Areas requiring additional research are also discussed. Methods: Electronic and manual literature search was conducted for key words such as tooth bleaching, and dental bleaching techniques using PubMed/MEDLINE, followed by manual selection of the studies that included whitening procedures in vital teeth. Results: The two main whitening agents are carbamide peroxide (CP) and hydrogen peroxide (HP or H2O2) whose concentration, duration of contact, and total treatment time can alter results. In addition, factors including the type of stain, and age of patient can affect results. Although whitening agents can affect tooth structure, restorative materials, and gingival tissues, the changes are temporary or can be treated using minimally invasive techniques. Conclusion: Areas requiring further research include the actual mechanism of whitening, its effect on tooth structure and restorative materials, and the development of an easy method to quantitate the degree of whitening in the dental office.

ACCURACY ANALYSIS OF DIFFERENT SURFACE RECONSTRUCTION MODELLING METHODS FOR HERITAGE OBJECTS DIGITIZED CONSIDERING PHOTOGRAMMETRIC DATA / SKIRTINGŲ RELJEFO MODELIAVIMO METODŲ, SUDARYTŲ PAGAL PAVELDO OBJEKTO FOTOGRAMETRINIUS DUOMENIS, TIKSLUMO ANALIZĖ / АНАЛИЗ ТОЧНОСТИ РАЗНЫХ МЕТОДОВ МОДЕЛИРОВАНИЯ ПОВЕРХНОСТИ, СОСТАВЛЕННЫХ В СООТВЕТСТВИИ С ФОТОГРАММЕТРИЧЕСКИМИ ДАННЫМИ ОБЪЕКТА АРХИТЕКТУРНОГО НАСЛЕДИЯ

2011 ◽  
Vol 37 (2) ◽  
pp. 56-62
Author(s):  
Jūratė Sužiedelytė-Visockienė ◽  
Aušra Kumetaitienė ◽  
Renata Bagdžiūnaitė
Keyword(s):  
Initial Data ◽  
Surface Reconstruction ◽  
Digital Images ◽  
Digital Camera ◽  
Accuracy Analysis ◽  
Triangulated Irregular Network ◽  
Modelling Analysis ◽  
The University ◽  
Modelling Methods ◽  
Made In

The article explains the possibilities of reconstructing heritage objects. Measurements were made using photogrammetric data received from digital images taken by the Canon EOS 1D Mark III digital camera calibrated in the Institute of Photogrammetry at the University of Bonn (Germany). The images were received applying the PhotoMod photogrammetric software produced in Russia. TIN (Triangulated Irregular Network) and an orthophoto map were made in the investigated objects. The modelling analysis of TIN data was made using ArcGIS software. The purpose of the article is to reconstruct the surface of heritage objects referring to photogrammetric data, to investigate accuracy dependence of heritage object reflection on the methods of preparing the initial data and to evaluate the influence of modelling methods on to the accuracy of reconstructing heritage objects when modelling photogrammetric data and selecting the most appropriate method of modelling parameters to restore the most accurate surface of the heritage object. Santrauka Straipsnyje aprašomos paveldo – architektūrinio objekto paviršiaus modeliavimo galimybės. Modeliavimas atliktas pagal fotogrametrinius objekto duomenis–skaitmenines nuotraukas, darytas kalibruota fotokamera Canon EOS 1D Mark III. Kamera kalibruota Bonos universiteto Fotogrametrijos institute (Vokietija). Objekto nuotraukos apdorotos fotogrametrine kompiuterine programa PhotoMod (Rusija). Sudaryta objekto ortofotografinė nuotrauka ir, parenkant skirtingus duomenų šaltinius, paviršiaus TIN (triangulated irregular network). Skirtingais metodais, naudojantis ArcGIS programa, atliktas fotogrametrinių TIN duomenų modeliavimas ir gauti objekto paviršiaus vaizdai. Įvertintas rezultatų tikslumas ir kokybė. Резюме Описываются возможности моделирования поверхности объекта архитектурного наследия. Моделирование осуществляется с использованием фотограмметрических данных объекта – цифровых снимков, снятых калибрированной цифровой камерой Canon EOS 1D Mark III. Камера калибрирована в Институте фотограмметрии Боннского университета (Германия). Снимки объекта обработаны по фотограмметрической компьютерной программе PhotoMod (Россия). Cделан ортофотографический снимок объекта и с помощью разных источников данных TIN (Triangulated Irregular Network) поверхности. Используя программу ArcGIS, разными методами проведено моделирование фотограмметрических TIN данных и получены изображения поверхности объекта. Осуществлена оценка точности и качества результатов.

scholarly journals Radiopacity of restorative materials using digital images

2006 ◽  
Vol 14 (2) ◽  
pp. 147-152 ◽  
Author(s):  
Leda Maria Pescinini Salzedas ◽  
Mário Jefferson Quirino Louzada ◽  
Antonio Braz de Oliveira Filho
Keyword(s):  
Restorative Material ◽  
Radiographic Image ◽  
Equivalent Thickness ◽  
Tooth Structure ◽  
Suitable Material ◽  
Dental Tissues ◽  
Permanent Molar ◽  
Restorative Materials ◽  
Phosphor Plate ◽  
The Mean

The radiopacity of esthetic restorative materials has been established as an important requirement, improving the radiographic diagnosis. The aim of this study was to evaluate the radiopacity of six restorative materials using a direct digital image system, comparing them to the dental tissues (enamel-dentin), expressed as equivalent thickness of aluminum (millimeters of aluminum). Five specimens of each material were made. Three 2-mm thick longitudinal sections were cut from an intact extracted permanent molar tooth (including enamel and dentin). An aluminum step wedge with 9 steps was used. The samples of different materials were placed on a phosphor plate together with a tooth section, aluminum step wedge and metal code letter, and were exposed using a dental x-ray unit. Five measurements of radiographic density were obtained from each image of each item assessed (restorative material, enamel, dentin, each step of the aluminum step wedge) and the mean of these values was calculated. Radiopacity values were subsequently calculated as equivalents of aluminum thickness. Analysis of variance (ANOVA) indicated significant differences in radiopacity values among the materials (P<0.0001). The radiopacity values of the restorative materials evaluated were, in decreasing order: TPH, F2000, Synergy, Prisma Flow, Degufill, Luxat. Only Luxat had significantly lower radiopacity values than dentin. One material (Degufill) had similar radiopacity values to enamel and four (TPH, F2000, Synergy and Prisma Flow) had significantly higher radiopacity values than enamel. In conclusion, to assess the adequacy of posterior composite restorations it is important that the restorative material to be used has enough radiopacity, in order to be easily distinguished from the tooth structure in the radiographic image. Knowledge on the radiopacity of different materials helps professionals to select the most suitable material, along with other properties such as biocompatibility, adhesion and esthetic.

The Future of Telepathology for the Developing World

2011 ◽  
Vol 135 (2) ◽  
pp. 211-214 ◽  
Author(s):  
Charles L Hitchcock
Keyword(s):  
Health Care ◽  
Patient Care ◽  
Digital Images ◽  
Virtual Slide ◽  
Digital Camera ◽  
Improve Patient Care ◽  
Limited Resources ◽  
Software Application ◽  
Open Platform ◽  
Delays In Diagnosis

Abstract Physician shortages are acute in developing countries, where disease burden is the greatest and resources for health care are very limited. A lack of pathologists in these countries has lead to delays in diagnosis and misdiagnoses that adversely affect patient care and survival. The introduction of telepathology into countries with limited resources for health care is but one of multiple approaches that can be used to alleviate the problem. Telepathology is the electronic transmission of digital images that can be used for education and diagnostic consultation. A basic system consists of a microscope with a mounted digital camera linked to a computer. The ability to produce histologic slides, to repair and maintain equipment, and to provide training are also needed for the successful use of this technology. iPath is a Web-based, open platform, software application which was developed at the University of Basel, Switzerland, for telepathology and which brings together pathologists from around the world to provide telepathology support for diagnostic consultation and provides education to centers with limited resources. The use of virtual-slide technology to provide a digital image of an entire glass slide is another technology for diagnostic consultation and pathology education. This technology requires more costly resources to support it, which may limit its utility in many areas. Telepathology can generate collections of digital images and virtual slides needed for training indigenous pathologists in their countries to become self-sufficient. Thus, the long-term goal of this technology is to improve patient care and survival.

A New Position Feedback Method for Manufacturing Equipment

2008 ◽  
Author(s):  
Chan Wong ◽  
Carlos Montes ◽  
Laine Mears ◽  
John Ziegert
Keyword(s):  
Digital Images ◽  
Liquid Crystal Display ◽  
Digital Camera ◽  
Position Sensing ◽  
Test Platform ◽  
Position Feedback ◽  
Feedback Method ◽  
Future Work ◽  
Pixel Matrix ◽  
Noise Reduction Algorithm

This paper presents an innovative real time 2-dimensional position feedback method, which processes visual input data from a target image on an actively-controlled planar pixel matrix. The objective is to demonstrate the ability to position an X-Y stage with high resolution, using direct position sensing of a dynamically controlled image. In order to achieve high spatial resolution using a pixel array as a target, an algorithm that processes both the geometric shape and the grayscale intensities of the image is implemented. The test platform consists of an X-Y stage carrying a Liquid Crystal Display (LCD) screen that is imaged by a stationary digital camera. The pixel intensities on the LCD screen are modified dynamically to provide 2-dimensional position command inputs that translate to the desired stage motion. The digital images acquired by the camera are used to provide position error feedback to the controller. Experimental results show that direct position sensing is possible to a certain degree of accuracy. However, in order to match today’s CNC machines’ accuracy levels further processing of the digital images is required. A noise reduction algorithm to filter the fluctuations of the measurements in the digital images is proposed as future work, as well as other considerations.

A Comparative Study of Light Transmission by Various Dental Restorative Materials and the Tooth Structure

2019 ◽  
Vol 45 (4) ◽  
pp. 442-452 ◽  
Author(s):  
N Ilie ◽  
G Furtos
Keyword(s):  
Optical Properties ◽  
Glass Ceramic ◽  
Light Transmission ◽  
Lithium Disilicate ◽  
Lithium Silicate ◽  
Restorative Process ◽  
Tooth Structure ◽  
Computer Aided ◽  
Restorative Materials ◽  
Cad Cam

Clinical Relevance Light transmission through dental materials and tooth structure has direct clinical implication on such factors as selecting an appropriate curing technique during a restorative process. SUMMARY Introduction: This study aims to quantify and compare the amount of light that passes through seven different types of direct and indirect restorative materials comprising light-cured resin based composites (regular and bulk-fill), computer-aided design/computer-aided manufacturing (CAD/CAM) restoratives such as resin based composites, poly(methyl methacrylate) (PMMA) resin, leucite glass-ceramic, lithium silicate glass-ceramic, feldspar ceramic, and the natural tooth structure. Methods and Materials: Individual sets (n=6) of plane-parallel test specimens (2 mm) of 32 restorative materials belonging to the aforementioned seven material types and the tooth structure were prepared. Within the analyzed materials, one leucite glass-ceramic and one lithium disilicate glass-ceramic were considered in two different translucencies. In addition, two light-cured resin composites, one CAD/CAM resin composite, and one lithium disilicate glass-ceramic were considered in two different shades. Optical properties (transmittance, T; absorbance, A; and opacity, O) of each material were calculated from the relationship between incident and transmitted irradiance [I(d)] using a violet-blue light-curing unit. Incident and transmitted irradiance were assessed in real time on a spectrophotometer. A multivariate analysis (general linear model) assessed the effects of various parameters on the optical properties. Results: A very strong influence of the parameter material was identified on I(d) (p&lt;0.001; partial eta squared, ηP2=0.953), T (p&lt;0.001; ηP2=0.951), A (p&lt;0.001; ηP2=0.925), and O (p&lt;0.001; ηP2=0.886), while the effect of the parameter material type was not significant (p=0.079, p=0.05, p=0.05, and p=0.051, respectively). Light attenuation differed significantly by material within each shade category and by shade category within the analyzed material. Conclusions: Attenuation of light through restorative materials and tooth structure is high (59.9% to 94.9%); thus, deficits in polymerization are difficult to compensate for by additional light exposure at the end of the restorative process.

Digital Images + Interactive Software = Enjoyable, Real Mathematics Modeling

2008 ◽  
Vol 101 (8) ◽  
pp. 568-572
Author(s):  
Andy Ventress
Keyword(s):  
Mathematical Modeling ◽  
Real World ◽  
Digital Images ◽  
Digital Camera ◽  
Mathematical Activity ◽  
Motivation To Learn ◽  
Interactive Software ◽  
Student Records

Mathematical modeling begins with a phenomenon, and what better way to represent a real-world phenomenon than with a digital camera? When a student records an image with a digital camera rather than doing an exercise from a textbook, that student becomes the owner of his own mathematical activity. Because the problem is now the student's, he or she has considerably more motivation to learn the mathematics.

scholarly journals FEM Analysis of Stress in Non-carious Cervical Lesion Restoration with Four Different Restorative Materials

2018 ◽  
Vol 55 (1) ◽  
pp. 42-45
Author(s):  
Gabriela Beresescu ◽  
Alina Ormenisan ◽  
Raluca Monica Comaneanu ◽  
Andreea Marilena Carp Veliscu ◽  
Marinela Minodora Manea ◽  
...  
Keyword(s):  
Finite Elements ◽  
Fem Analysis ◽  
Two Dimensional ◽  
Cervical Lesions ◽  
Normal Functioning ◽  
Plane Model ◽  
Tooth Structure ◽  
Lower Canine ◽  
Restorative Materials ◽  
Elastic Characteristics

The purpose of this study was to evaluate the behavior of four restorative materials in non-carious cervical lesions when subjected to exterior stresses of different magnitude. A plane model reproducing a vestibular and lingual section of the lower canine was created. The finite elements are of a two- dimensional type (2D) - quadrilater. Four restorative materials were used: Vitrebond, Dyract AP, Vitremer, Fuji IX. All materials were considered to be isotropic and elastic. Nodal charges were of 40 degrees to vertical, applied on the vestibular side at h=8.993mm to gingival crest, of increasing magnitudes:20, 40, 60, 80, 100, 120, 140, 160 N. The results of this study showed that after restoration stress values in all the elements are (with minimal differences) similar to those in the healthy tooth; a correct restoration leads to normal functioning of the tooth. It can be considered that particular types of restoring materials should be used in particular lesions to be restored, depending on the location of the lesion and the elastic characteristics of the materials and tooth structure. A correct restoration leads to normal functioning of the tooth.

scholarly journals Increasing Quality of Anatomical Education by Introduction of Digital Imaging Into Documentation of Topographic Dissections

2001 ◽  
Vol 44 (4) ◽  
pp. 145-147 ◽  
Author(s):  
Dáša Slížová ◽  
Otakar Krs ◽  
Blanka Pospíšilová
Keyword(s):  
Digital Imaging ◽  
Digital Camera ◽  
Computer Processing ◽  
Human Anatomy ◽  
New Approach ◽  
Professional Career ◽  
Normal Human ◽  
Manual Skills ◽  
Essential Prerequisite

Knowledge of topographic anatomy is essential prerequisite for any physician to be successful in professional career. That is why we pay special attention to topographic dissections completing course of normal human anatomy at our department. Dissection procedure is subjected to relatively rigid rules demanding removal of some superficial structures during preparation of deeper layers. Thus some important structures get lost for further learning and also for final evaluation of students knowledge and manual skills. Therefore we decided to introduce digital imaging into the recording of course of preparation, the topographic relationships and unique variations. Digital acquisition of pictures through still digital camera makes possible to bypass the wet photographic process and provides instant graphic inputs for further computer processing. The image files can be further edited, printed, archived on various media and then may be used for instructional, test, evaluative, and publication purposes. Moreover, own original pictorial material is feasible to be presented at anatomy lectures. Practical results of this new approach, besides higher attractiveness and motivation impact, allow us to conclude that systematic digital acquisition of dissection pictures combined with computer processing fairly increases quality of anatomical education.

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