The Experts below are selected from a list of 3411 Experts worldwide ranked by ideXlab platform
Robert J. Loushine - One of the best experts on this subject based on the ideXlab platform.
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Measurement of endodontic file lengths: calibrated versus uncalibrated digital images.
Journal of endodontics, 2001Co-Authors: Robert J. Loushine, R. Norman Weller, W. Frank Kimbrough, Brad J. PotterAbstract:This in vitro study compared the accuracy of file length measurements made on calibrated and Uncalibrated direct digital images. Endodontic files of known lengths and ISO sizes were used in 10 single-rooted, relatively straight teeth within cadaver specimens. The crowns of the teeth were ground flat and an Orthodontic Wire of known length was secured to the coronal surface. This Wire was placed mesiodistally and perpendicular to the root and served as the reference point for the file measurement and as a calibration reference length. A #20 file was hand-measured to a length that reached the apical third of each tooth. It was inserted and a radio-graphic image was secured. The instalment was re-measured three additional times at different lengths on the same tooth and reinserted before each image acquisition. Thus 40 digital images were acquired using a GE X-ray unit and a Schick Computed Dental Radiography (CDR) #2 sensor. These images were placed in random order, and an independent, blinded investigator determined the file lengths using on-screen calibrated and Uncalibrated measurement of the CDR image with a straight-line and multiple-line measuring technique. The experimental measurements were compared with each other and with the known clinical measurements. A two-way analysis of variance indicated that there was a statistically significant difference showing that the calibrated measurements were more accurate than the Uncalibrated measurements (p = 0.0001), and there was no significant difference between the straight-line and multiple-line measuring techniques (p = 0.14).
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Measurement of endodontic file lengths: a density profile plot analysis.
Journal of endodontics, 2000Co-Authors: Michael E. Piepenbring, Brad J. Potter, R. Norman Weller, Robert J. LoushineAbstract:The purpose of this study was to evaluate measurements of endodontic files of known length and diameter using a density profile plot analysis of digital images. Ten single-rooted teeth with relatively straight roots in cadaver specimens were used. The crowns of the teeth were removed and a rectangular Orthodontic Wire, 5.13 mm in length, was placed horizontally on the occlusal surface to serve as a calibration reference point. The #8, #10, #15, and #20 FlexOFiles were measured to the nearest 0.5 mm and then placed to four working lengths that terminated within the apical third of each root. A GE X-ray unit and a Schick CDR #2 sensor were used to digitally acquire 160 images. The digital images were placed in random order and an independent, blinded investigator determined the file length using a density profile plot analysis. The measurements generated by the histogram analysis (experimental) were compared with the original clinical measurements. The paired t test, intraclass correlation coefficient, and the Bradley-Blackwood test were used to assess reliability. The results revealed that the means of the experimental measurements of all file sizes were within 0.5 mm of the known lengths and were always shorter than the known lengths. Also, the larger the file size the less deviation from the known lengths: #20, −0.16 mm (p = 0.0001); #15, −0.21 mm (p = 0.0001); #10, −0.34 mm (p = 0.0001); and #8, −0.45 mm (p = 0.0001). This study demonstrated that the density profile plot analysis might be a useful adjunct for the measurement of endodontic file lengths on a digital image.
Brad J. Potter - One of the best experts on this subject based on the ideXlab platform.
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Measurement of endodontic file lengths: calibrated versus uncalibrated digital images.
Journal of endodontics, 2001Co-Authors: Robert J. Loushine, R. Norman Weller, W. Frank Kimbrough, Brad J. PotterAbstract:This in vitro study compared the accuracy of file length measurements made on calibrated and Uncalibrated direct digital images. Endodontic files of known lengths and ISO sizes were used in 10 single-rooted, relatively straight teeth within cadaver specimens. The crowns of the teeth were ground flat and an Orthodontic Wire of known length was secured to the coronal surface. This Wire was placed mesiodistally and perpendicular to the root and served as the reference point for the file measurement and as a calibration reference length. A #20 file was hand-measured to a length that reached the apical third of each tooth. It was inserted and a radio-graphic image was secured. The instalment was re-measured three additional times at different lengths on the same tooth and reinserted before each image acquisition. Thus 40 digital images were acquired using a GE X-ray unit and a Schick Computed Dental Radiography (CDR) #2 sensor. These images were placed in random order, and an independent, blinded investigator determined the file lengths using on-screen calibrated and Uncalibrated measurement of the CDR image with a straight-line and multiple-line measuring technique. The experimental measurements were compared with each other and with the known clinical measurements. A two-way analysis of variance indicated that there was a statistically significant difference showing that the calibrated measurements were more accurate than the Uncalibrated measurements (p = 0.0001), and there was no significant difference between the straight-line and multiple-line measuring techniques (p = 0.14).
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Measurement of endodontic file lengths: a density profile plot analysis.
Journal of endodontics, 2000Co-Authors: Michael E. Piepenbring, Brad J. Potter, R. Norman Weller, Robert J. LoushineAbstract:The purpose of this study was to evaluate measurements of endodontic files of known length and diameter using a density profile plot analysis of digital images. Ten single-rooted teeth with relatively straight roots in cadaver specimens were used. The crowns of the teeth were removed and a rectangular Orthodontic Wire, 5.13 mm in length, was placed horizontally on the occlusal surface to serve as a calibration reference point. The #8, #10, #15, and #20 FlexOFiles were measured to the nearest 0.5 mm and then placed to four working lengths that terminated within the apical third of each root. A GE X-ray unit and a Schick CDR #2 sensor were used to digitally acquire 160 images. The digital images were placed in random order and an independent, blinded investigator determined the file length using a density profile plot analysis. The measurements generated by the histogram analysis (experimental) were compared with the original clinical measurements. The paired t test, intraclass correlation coefficient, and the Bradley-Blackwood test were used to assess reliability. The results revealed that the means of the experimental measurements of all file sizes were within 0.5 mm of the known lengths and were always shorter than the known lengths. Also, the larger the file size the less deviation from the known lengths: #20, −0.16 mm (p = 0.0001); #15, −0.21 mm (p = 0.0001); #10, −0.34 mm (p = 0.0001); and #8, −0.45 mm (p = 0.0001). This study demonstrated that the density profile plot analysis might be a useful adjunct for the measurement of endodontic file lengths on a digital image.
Takashi Ono - One of the best experts on this subject based on the ideXlab platform.
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a new Orthodontic force system for moment control utilizing the flexibility of common Wires evaluation of the effect of contractile force and hook length
Journal of the Formosan Medical Association, 2018Co-Authors: Wei Jen Lai, Yoshiyuki Midorikawa, Zuisei Kanno, Hiroshi Takemura, Kazuhiro Suga, Kohei Soga, Takashi OnoAbstract:Background/Purpose The application of an appropriate force system is indispensable for successful Orthodontic treatments. Second-order moment control is especially important in many clinical situations, so we developed a new force system composed of a straight Orthodontic Wire and two crimpable hooks of different lengths to produce the second-order moment. The objective of this study was to evaluate this new force system and determine an optimum condition that could be used in clinics. Methods We built a premolar extraction model with two teeth according to the concept of a modified Orthodontic simulator. This system was activated by applying contractile force from two hooks that generated second-order moment and force. The experimental device incorporated two sensors, and forces and moments were measured along six axes. We changed the contractile force and hook length to elucidate their effects. Three types of commercial Wires were tested. Results The second-order moment was greater on the longer hook side of the model. Vertical force balanced the difference in moments between the two teeth. Greater contractile force generated a greater second-order moment, which reached a limit of 150 g. Excessive contractile force induced more undesired reactions in the other direction. Longer hooks induced greater moment generation, reaching their limit at 10 mm in length. Conclusion The system acted similar to an off-center V-bend and can be applied in clinical practice as an unconventional loop design. We suggest that this force system has the potential for second-order moment control in clinical applications.
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A new Orthodontic force system for moment control utilizing the flexibility of common Wires: Evaluation of the effect of contractile force and hook length
Elsevier, 2018Co-Authors: Wei Jen Lai, Yoshiyuki Midorikawa, Zuisei Kanno, Hiroshi Takemura, Kazuhiro Suga, Kohei Soga, Takashi OnoAbstract:The application of an appropriate force system is indispensable for successful Orthodontic treatments. Second-order moment control is especially important in many clinical situations, so we developed a new force system composed of a straight Orthodontic Wire and two crimpable hooks of different lengths to produce the second-order moment. The objective of this study was to evaluate this new force system and determine an optimum condition that could be used in clinics. Methods: We built a premolar extraction model with two teeth according to the concept of a modified Orthodontic simulator. This system was activated by applying contractile force from two hooks that generated second-order moment and force. The experimental device incorporated two sensors, and forces and moments were measured along six axes. We changed the contractile force and hook length to elucidate their effects. Three types of commercial Wires were tested. Results: The second-order moment was greater on the longer hook side of the model. Vertical force balanced the difference in moments between the two teeth. Greater contractile force generated a greater second-order moment, which reached a limit of 150 g. Excessive contractile force induced more undesired reactions in the other direction. Longer hooks induced greater moment generation, reaching their limit at 10 mm in length. Conclusion: The system acted similar to an off-center V-bend and can be applied in clinical practice as an unconventional loop design. We suggest that this force system has the potential for second-order moment control in clinical applications
Rebeka Rudolf - One of the best experts on this subject based on the ideXlab platform.
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stress dependent electrical resistivity of Orthodontic Wire from the shape memory alloy niti
Materials & Design, 2014Co-Authors: Janko Fercec, Ivan Anžel, Rebeka RudolfAbstract:Abstract The aim of this study was to compare and evaluate the stress induced martensitic phase under different loading conditions in Orthodontic Wire from the Shape Memory Alloy Nickel–Titanium (NiTi). For this purpose we investigated the phase transformation from austenite to martensitic due to the different loading conditions by measuring the electrical resistance which could show the type of deformation which occurs at the beginning of phase transformations. In this framework we developed two special devices for measurements of electrical resistance in different types of load and their combination on the Orthodontic Wire. These results were compared with the analytically calculated stresses in the Orthodontic Wire. It was shown that they caused complex or multi-axial stress state phase transformation rather than other more simple load such as uniaxial loading. Finally, the article presents the deformation which occurs at the change of phase that is nearly connected to the useful superelasticity effect of the Shape Memory Alloy NiTi.
R. Norman Weller - One of the best experts on this subject based on the ideXlab platform.
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Measurement of endodontic file lengths: calibrated versus uncalibrated digital images.
Journal of endodontics, 2001Co-Authors: Robert J. Loushine, R. Norman Weller, W. Frank Kimbrough, Brad J. PotterAbstract:This in vitro study compared the accuracy of file length measurements made on calibrated and Uncalibrated direct digital images. Endodontic files of known lengths and ISO sizes were used in 10 single-rooted, relatively straight teeth within cadaver specimens. The crowns of the teeth were ground flat and an Orthodontic Wire of known length was secured to the coronal surface. This Wire was placed mesiodistally and perpendicular to the root and served as the reference point for the file measurement and as a calibration reference length. A #20 file was hand-measured to a length that reached the apical third of each tooth. It was inserted and a radio-graphic image was secured. The instalment was re-measured three additional times at different lengths on the same tooth and reinserted before each image acquisition. Thus 40 digital images were acquired using a GE X-ray unit and a Schick Computed Dental Radiography (CDR) #2 sensor. These images were placed in random order, and an independent, blinded investigator determined the file lengths using on-screen calibrated and Uncalibrated measurement of the CDR image with a straight-line and multiple-line measuring technique. The experimental measurements were compared with each other and with the known clinical measurements. A two-way analysis of variance indicated that there was a statistically significant difference showing that the calibrated measurements were more accurate than the Uncalibrated measurements (p = 0.0001), and there was no significant difference between the straight-line and multiple-line measuring techniques (p = 0.14).
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Measurement of endodontic file lengths: a density profile plot analysis.
Journal of endodontics, 2000Co-Authors: Michael E. Piepenbring, Brad J. Potter, R. Norman Weller, Robert J. LoushineAbstract:The purpose of this study was to evaluate measurements of endodontic files of known length and diameter using a density profile plot analysis of digital images. Ten single-rooted teeth with relatively straight roots in cadaver specimens were used. The crowns of the teeth were removed and a rectangular Orthodontic Wire, 5.13 mm in length, was placed horizontally on the occlusal surface to serve as a calibration reference point. The #8, #10, #15, and #20 FlexOFiles were measured to the nearest 0.5 mm and then placed to four working lengths that terminated within the apical third of each root. A GE X-ray unit and a Schick CDR #2 sensor were used to digitally acquire 160 images. The digital images were placed in random order and an independent, blinded investigator determined the file length using a density profile plot analysis. The measurements generated by the histogram analysis (experimental) were compared with the original clinical measurements. The paired t test, intraclass correlation coefficient, and the Bradley-Blackwood test were used to assess reliability. The results revealed that the means of the experimental measurements of all file sizes were within 0.5 mm of the known lengths and were always shorter than the known lengths. Also, the larger the file size the less deviation from the known lengths: #20, −0.16 mm (p = 0.0001); #15, −0.21 mm (p = 0.0001); #10, −0.34 mm (p = 0.0001); and #8, −0.45 mm (p = 0.0001). This study demonstrated that the density profile plot analysis might be a useful adjunct for the measurement of endodontic file lengths on a digital image.