• Title/Summary/Keyword: Dimensional changes

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Three-dimensional assessment of condylar surface changes and remodeling after orthognathic surgery

  • Lee, Jung-Hye;Lee, Woo-Jin;Shin, Jae-Myung;Huh, Kyung-Hoe;Yi, Won-Jin;Heo, Min-Suk;Lee, Sam-Sun;Choi, Soon-Chul
    • Imaging Science in Dentistry
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    • v.46 no.1
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    • pp.25-31
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    • 2016
  • Purpose: This study was performed to evaluate condylar surface changes and remodeling after orthognathic surgery using three-dimensional computed tomography (3D CT) imaging, including comparisons between the right and left sides and between the sexes. Materials and Methods: Forty patients (20 males and 20 females) who underwent multi-detector CT examinations before and after surgery were selected. Three-dimensional images comprising thousands of points on the condylar surface were obtained before and after surgery. For the quantitative assessment of condylar surface changes, point-to-point (preoperative-to-postoperative) distances were calculated using 3D processing software. These point-to-point distances were converted to a color map. In order to evaluate the types of condylar remodeling, the condylar head was divided into six areas (anteromedial, anteromiddle, anterolateral, posteromedial, posteromiddle, and posterolateral areas) and each area was classified into three types of condylar remodeling (bone formation, no change, and bone resorption) based on the color map. Additionally, comparative analyses were performed between the right and left sides and according to sex. Results: The mean of the average point-to-point distances on condylar surface was $0.11{\pm}0.03mm$. Bone resorption occurred more frequently than other types of condylar remodeling, especially in the lateral areas. However, bone formation in the anteromedial area was particularly prominent. No significant difference was found between the right and left condyles, but condylar surface changes in males were significantly larger than in females. Conclusion: This study revealed that condylar remodeling exhibited a tendency towards bone resorption, especially in the lateral areas. Condylar surface changes occurred, but were small.

Dimensional stability of rubber impression materials immersed in iodophor disinfectant (요오드 소독제에 침전된 고무인상재의 체적안정성)

  • Choi, Mee-Ra;Park, Chan-Jin
    • Journal of Dental Rehabilitation and Applied Science
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    • v.30 no.1
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    • pp.23-27
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    • 2014
  • Purpose: The purpose of this study was to determine the dimensional stability of three rubber impression materials (polysulfide, polyvinylsiloxane, polyether) in an iodophor disinfectant. Materials and Methods: Seventy-two impressions were made with each material and divided into control, 10-minute, and 30-minute immersion groups using an iodophor as the disinfectant. A microscope was used to measure dimensional changes in the stone casts made from each group of impressions, and the percent change was analyzed using a two-way ANOVA (P = 0.05). Results: All dimensional changes after iodophor disinfection were small in 10 minute groups, however, showed significantly increased in 30 minute groups (P < 0.05). Conclusion: Clinically, it can be recommended to use iodophor disinfectant for rubber materials within 10 minute.

Development of Methods for Protein Extraction from Three Major Korean Fermented Soy Foods for 2-Dimensional Gel and Mass Spectrometric Analyses

  • Lim, Jin-Kyu
    • Journal of Applied Biological Chemistry
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    • v.51 no.3
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    • pp.88-94
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    • 2008
  • Three different protein extraction methods-phenol extraction, trichloroacetic acid (TCA) precipitation, and desalting/TCA precipitation-were compared to determine the optimal reproducible high resolution 2-dimensional (2-D) electrophoresis for each chungkugjang, doenjang, and kochujang samples. The soluble proteins from Chungkugjang extracted by phenol were separated with high reproducibility and resolution, and gained 1.75- to 3-fold more protein spots on 2-D gel than those from the other methods. On the contrary, the extracted proteins from doenjang and kochujang treated by desalting/TCA precipitation method showed about 1.5- to 3.3-fold more protein spots on 2-D gel. Using the established methods, the changes in the protein profiles of the fermented soy foods were monitored during the fermentation period by 2-DE. One of the major proteins in soy, $\beta$-conglycinin $\alpha$-subuint, and some proteins with unknown functions were localized on 2-D gel as the protease-resistant proteins throughout the fermentation period of doenjang. Changes in the protein profile monitored by the established methods can provide basic information on unfolding the mechanisms of the generation of biofunctional activity in the fermented soy foods.

Comparison of Dynamic Sorption and Hygroexpansion of Wood by Different Cyclic Hygrothermal Changing Effects

  • Yang, Tiantian;Ma, Erni
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.2
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    • pp.191-203
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    • 2016
  • To investigate the dynamic sorptive and hygroexpansive behaviors of wood by different cyclic hygrothermal changing effects, poplar (populus euramericana Cv.) specimens, were exposed to dynamic sorption processes where relative humidity (RH) and temperature changed simultaneously in sinusoidal waves at 75-45% and $5-35^{\circ}C$ (condition A) and where RH changed sinusoidally at 75-45% but temperature was controlled at $20^{\circ}C$ (condition B), both for three cyclic periods of 1, 6, and 24 h. Moisture and dimensional changes measured during the cycling gave the following results: Moisture and transverse dimensional changes were generally sinusoidal. Moisture and dimensional amplitude increased with increasing cyclic period but all were lower for thicker specimens. The amplitude ratio of condition A to condition B ranged from 1.0 to 1.6 with the maximum value of 1.57 occurring at the shortest cyclic period, not as much as expected. T/R increased as cyclic period increased or specimen thickness decreased. T/R from condition B was weaker than that from condition A. Sorption and swelling hysteresis existed in both conditions. Sorption hysteresis was negatively related to cyclic period but in positive correlation with specimen thickness. Sorption hysteresis was found more obvious in condition B, while moisture sorption coefficient and humidity expansion coefficient showed the opposite results.

A STUDY ON THE VISCO-ELASTIC PROPERTIES OF FOUR CURRENTLY USED TISSUE CONDITIONERS (수종의 조직 양화재에서 탄성 변형과 복원에 관한 연구)

  • Choi Sung-Ho;Shim June-Sung;Moon Hong-Seok;Chung Moon-Kyu
    • The Journal of Korean Academy of Prosthodontics
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    • v.41 no.1
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    • pp.35-47
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    • 2003
  • The dimensional stability of tissue conditioners characterizes the ability of the materials to yield accurate functional impressions of oral mucosa. This study evaluated the viscoelastic property and the linear dimensional changes with the factor of time and thickness of tissue conditioners ($COE-COMFORT^{TM}$, Visco-gel. $COE-SOFT^{TM}$, Soft-Liner). The thickness of these materials were changed (1.5mm, 3.0mm) and the percentage changes in dimension were measured at 1h, 12h, 24h, 36h, 3day, 7day after specimen preparation. From the results large differences appear between the various tissue conditioners. The results suggest that the period recommended for forming functional impression would be 2-3days after insertion in the mouth. in addition. it is important to select tissue conditioners suitable for functional impression because of the wide range of dimensional stability among the materials.

EFFECT OF SECONDARY HEAT TREATMENT ON DIMENSIONAL CHANGES OF ACRYLIC RESIN PARTIAL DENTURE BASE (2차 가열에 의한 국소의치상의 변형에 관한 실험적 연구)

  • Jang, Byung-Gun;Lee, Ho-Yong
    • The Journal of Korean Academy of Prosthodontics
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    • v.27 no.1
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    • pp.193-211
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    • 1989
  • The purpose of this study was to investigate the effect of secondary heat treatment on dimensional changes of acrylic resin partial denture base. For this study, 6 specimens were made: 2 groups of 2 specimens, each was treated with $125^{\circ}C$ dry heat and glycerine heat for 3 minutes, and the others were prepared for control group. The change of the internal diameter of specimens were measured after 3 hrs, 1 day, 1 week, 2 weeks, 4 weeks by three-dimensional space analyzer. The results were as follows : 1. All of the acrylic resin denture bases showed tissue ward thermal contraction. 2. Thermal contraction of the mesial area reinforced with metal framework was lesser than that of the distal area without metal framework. 3. Thermal contraction of the lingual flange reinforced with metal framework occured more slowly than that of the buccal flange without the metal framework. 4. The thermal contraction of dry heat treated acrylic resin base, compared to glycerine heat group, was moderately greater and occurred acutely.

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Numerical Simulation of Three Dimensional Free Surface Flow (3차원 자유표면 유동의 수치 시뮬레이션)

  • 강신영
    • Journal of Ocean Engineering and Technology
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    • v.4 no.1
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    • pp.55-61
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    • 1990
  • For the tracking of three dimensional free surface motions, a method referred to as the Volume of Fluid(VOF) algorithm is extended. In order to calculate the slope of three dimensional free surface which is the most important for the advection algorithm that decides the amount of fluid from cell to cell and for the application of free surface boundary condition, a simple method utilizing two dimensional slope informations is introduced. The extended algroithm is tested by demonstrating the simulation of a propagating sinusoidal wave through the channel whose width changes abruptly.

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Numerical study of Three-Dimensional Characteristics of Flow Field and Compression Wave Induced by High Speed Train Entering into a Tunnel (터널에 진입하는 고속전철에 의한 3차원 점성유동과 압축파 특성에 관한 수치해석적 연구)

  • Shin C. H.;Park W. G.
    • 한국전산유체공학회:학술대회논문집
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    • 2000.05a
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    • pp.91-98
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    • 2000
  • The three-dimensional unsteady compressible Full Navier-Stokes equation solver with sliding multi-block method has been applied to analyze three dimensional characteristics of the flow field and compression wave around the high speed train which Is entering into a tunnel. The numerical scheme of AF + ADI was used to efficiently solve Navier-Stokes equations in the curvilinear coordinate system. The vortex formation around the nose region was found and the generation of compression wave due to the blockage effects was observed ahead of the train in the form of plane wave. The three dimensional characteristics of the flow field compared to the analytic results were discussed in detail. The variation of pressure of tunnel wall surface and velocity profile of the train are identified as the train enters into a tunnel. The changes in aerodynamic forces and streamlines of each specific sections are also discussed and presented.

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Numerical study of Three-Dimensional Viscous Flow and Compression Wave Induced by the High Speed Train Entering into a Tunnel (터널에 진입하는 고속전철 주위의 3차원 점성유동과 압축파 특성에 관한 수치해석적 연구)

  • Shin C. H.;Park W. G.
    • Journal of computational fluids engineering
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    • v.5 no.3
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    • pp.23-31
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    • 2000
  • The three-dimensional unsteady compressible Full Navier-Stokes equation solver with sliding multi-block method has been applied to analyze three dimensional characteristics of the viscous flow field and compression wave around the high speed train which is entering into a tunnel. The numerical scheme of AF + ADI was used to efficiently solve Navier-Stokes equations in the curvilinear coordinate system. The vortex formation owing to the viscous interaction around the train was found and the generation of compression wave due to the blockage effects was observed ahead of the train in the form of plane wave. The three dimensional characteristics of the flow field compared to the analytic results were discussed in detail. The variation of pressure of tunnel wall surface and velocity profile of the train are identified as the train enters into a tunnel. The changes in aerodynamic forces and streamlines of each specific sections are also discussed.

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Two-Dimensional Correlation Analysis of Sum-Frequency Vibrational Spectra of Langmuir Monolayers

  • Lee, Jonggwan;Sung, Woongmo;Kim, Doseok
    • Journal of the Optical Society of Korea
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    • v.18 no.5
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    • pp.558-563
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    • 2014
  • Sum-frequency generation spectra of a Langmuir monolayer on water surface at varying surface areas were studied with two-dimensional correlation analysis. Upon enlarging the area/molecule of the Langmuir monolayer, the sum-frequency spectra changed reflecting the conformation change of the alkyl chains of the molecules in the monolayer. These changes stood out more clearly by employing two-dimensional correlation analysis of the above sum-frequency spectra. Features not very pronounced in the original spectra such as closely-spaced spectral bands can also be easily distinguished in the two-dimensional correlation spectra.