http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Konstantinos Dimitriadis (검색결과 4 건)
- 무료
- 기관 내 무료
- 유료
-
Dimitriadis, Konstantinos,Spyropoulos, Konstantinos,Papadopoulos, Triantafillos The Korean Academy of Prosthodonitics 2018 The Journal of Advanced Prosthodontics Vol.10 No.1
PURPOSE. The aim of the present study was to record the metal-ceramic bond strength of a feldspathic dental porcelain and a Co-Cr alloy, using the Direct Metal Laser Sintering technique (DMLS) for the fabrication of metal substrates. MATERIALS AND METHODS. Ten metal substrates were fabricated with powder of a dental Co-Cr alloy using DMLS technique (test group) in dimensions according to ISO 9693. Another ten substrates were fabricated with a casing dental Co-Cr alloy using classic casting technique (control group) for comparison. Another three substrates were fabricated using each technique to record the Modulus of Elasticity (E) of the used alloys. All substrates were examined to record external and internal porosity. Feldspathic porcelain was applied on the substrates. Specimens were tested using the three-point bending test. The failure mode was determined using optical and scanning electron microscopy. The statistical analysis was performed using t-test. RESULTS. Substrates prepared using DMLS technique did not show internal porosity as compared to those produced using the casting technique. The E of control and test group was $222{\pm}5.13GPa$ and $227{\pm}3GPa$, respectively. The bond strength was $51.87{\pm}7.50MPa$ for test group and $54.60{\pm}6.20MPa$ for control group. No statistically significant differences between the two groups were recorded. The mode of failure was mainly cohesive for all specimens. CONCLUSION. Specimens produced by the DMLS technique cover the lowest acceptable metal-ceramic bond strength of 25 MPa specified in ISO 9693 and present satisfactory bond strength for clinical use.
-
Konstantinos Dimitriadis,Athanasios Konstantinou Sfikas,Spyros Kamnis,Pepie Tsolka,Simeon Agathopoulos 대한치과보철학회 2022 The Journal of Advanced Prosthodontics Vol.14 No.2
PURPOSE. Microstructural and physico-mechanical characterization of highly translucent zirconia, prepared by milling technology (CAD-CAM) and repeated firing cycles, was the main aim of this in vitro study. MATERIALS AND METHODS. Two groups of samples of two commercial highly-translucent yttria-stabilized dental zirconia, VITA YZ-HTWhite (Group A) and Zolid HT + White (Group B), with dimensions according to the ISO 6872 “Dentistry - Ceramic materials”, were prepared. The specimens of each group were divided into two subgroups. The specimens of the first subgroups (Group A1 and Group B1) were merely the sintered specimens. The specimens of the second subgroups (Group A2 and Group B2) were subjected to 4 heat treatment cycles. The microstructural features (microstructure, density, grain size, crystalline phases, and crystallite size) and four mechanical properties (flexural strength, modulus of elasticity, Vickers hardness, and fracture toughness) of the subgroups (i.e. before and after heat treatment) were compared. The statistical significance between the subgroups (A1/A2, and B1/B2) was evaluated by the t-test. In all tests, P values smaller than 5% were considered statistically significant. RESULTS. A homogenous microstructure, with no residual porosity and grains sized between 500 and 450 nm for group A and B, respectively, was observed. Crystalline yttria-stabilized tetragonal zirconia was exclusively registered in the X-ray diffractograms. The mechanical properties decreased after the heat treatment procedure, but the differences were not statistically significant. CONCLUSION. The produced zirconia ceramic materials can be safely (i.e., according to the ISO 6872) used in extensive fixed prosthetic restorations, such as substructure ceramics for three-unit prostheses involving the molar restoration and substructure ceramics for prostheses involving four or more units. Consequently, milling technology is an effective manufacturing technology for producing zirconia substructures for dental fixed all-ceramic prosthetic restorations.
-
Malioris Apostolos,Dimitriadis Georgios,Kampantais Spyridon,Gkotsos Georgios,Vakalopoulos Ioannis,Ioannidis Stavros,Hatzimoutatidis Konstantinos,Hatzichristou Dimitrios 대한배뇨장애요실금학회 2015 International Neurourology Journal Vol.19 No.4
Purpose: The aim of the present study was to determine the diagnostic accuracy of conventional and ambulatory urodynamic studies (UDS) in estimating neobladder function. Methods: We evaluated 32 patients who underwent radical cystectomy and orthotopic Hautmann W neobladder with Abol- Enein-Ghoneim uretero-intestinal anastomosis for bladder cancer. The patients were initially examined by using both conventional and ambulatory UDS. Results: Conventional UDS detected a very high mean intravesical pressure at maximum capacity (53.7±17.5 cm H2O). By contrast, the mean intravesical pressure detected by using ambulatory UDS (which reflects the dominant pattern of pressure variation during filling) was significantly lower (34.4±5.2 cm H2O, P<0.001). The comparison between intravesical pressure at half of maximum capacity in conventional UDS and the mean value in ambulatory UDS did not show significant difference (P=0.152). The mean voided volume in conventional UDS was greater than both the mean voided volume (P<0.001) and the mean maximum voided volume in ambulatory UDS (P=0.001). However, this difference did not affect the postvoid residual urine volume measured in both studies (P=0.207). Moreover, incontinence episodes recorded in ambulatory UDS were more frequent but not statistically significantly different from those recorded in conventional UDS (P=0.332). Conclusions: The estimation of neobladder function by means of ambulatory UDS seems to provide interesting research data for the mode of lower urinary tract function in patients with orthotopic substitution after radical cystectomy. The great high value in ambulatory UDS, in cases in which conventional UDS had failed, is due to the exposure of daily and nocturnal incontinence episodes, confirming our patients’ complaints.
-
Surgical Reconstruction of Traumatic Pseudoaneurysm of Palmar Arch Caused by Blunt Trauma
Nikolaos Papatheodorou,Konstantinos Dimitriadis,Damianos Doukas,Christos Argyriou,George S. Georgiadis 대한혈관외과학회 2022 Vascular Specialist International Vol.38 No.4
Although rare, pseudoaneurysms (PAs) of the palmar arch are mostly considered benign. However, they can cause severe complications if left untreated or misdiagnosed. There are a few data on traumatic PAs of the palmar arch, particularly those most commonly caused by penetrating hand injuries. However, PAs caused by blunt trauma are more insidious in onset, presenting as a painful pulsatile mass in the palmar area of the hand, and require prompt diagnosis and management to avoid catastrophic sequelae. Our case is the first study to describe a patient with traumatic PA of the palmar arch caused by blunt trauma that was treated with surgical reconstruction and venous bypass interposition.
ScienceON연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
