scholarly journals Influence of Vinyl Polysiloxane Impression Techniques on Marginal Fit of Metal Frameworks for Fixed Partial Dentures

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4684
Author(s):  
Joseph Nissan ◽  
Ofir Rosner ◽  
Gal Rosen ◽  
Sarit Naishlos ◽  
Eran Zenziper ◽  
...  
Keyword(s):  
Accuracy Assessment ◽  
Partial Denture ◽  
Factors Affecting ◽  
Fixed Partial Denture ◽  
Impression Technique ◽  
Metal Framework ◽  
Group 2 ◽  
Test Failure ◽  
Group 1

Impression technique is one of the factors affecting restoration fit accuracy, which is a major aspect influencing its survival. The purpose of this study is to compare, in vivo, the effect of two commonly used Vinyl Polysiloxane (VPS) impression techniques on the metal framework fitting of fixed partial dentures. Ninety-two consecutive patients, diagnosed as partially edentulous, treated by fixed partial denture restorations, participated in the study. Group 1-impressions (n = 44) were subjected to the 1-step technique, while group 2 impressions (n = 48) were subjected the 2-step technique. Three accuracy assessment common methods: probe, tactile sense and radiographic test, were used to validate the clinical fit of the metal framework. Misfit was defined as even one test failure. Twenty-one (22.8%) out of 92 metal frameworks exhibited metal frameworks misfit, whereas the other 71 (77.2%) were found to be accurate. Group 1 presented significantly (p = 0.04) more metal frameworks misfit, 14/44 (31.8%) vs. 7/48 (14.6%). Restoration location (maxilla vs. mandible) had no statistically significant impact on the results (p = 0.461). The use of the VPS putty/wash 2-step impression technique is recommended to improve the clinical fit of fixed partial denture restorations.

scholarly journals Effect of Mixing and Impression Techniques Using Vinyl Polysiloxane (VPS) on the Accuracy of Fixed Partial Dentures

2021 ◽  
Vol 11 (17) ◽  
pp. 7845
Author(s):  
Helena Zelikman ◽  
Ofir Rosner ◽  
Sarit Naishlos ◽  
Hanaa Azem ◽  
Isabelle Meinster ◽  
...  
Keyword(s):  
Mechanical Mixing ◽  
Two Stage ◽  
Partial Denture ◽  
Significant Statistical Difference ◽  
Fixed Partial Denture ◽  
Impression Technique ◽  
Impression Materials ◽  
Metal Framework ◽  
The One ◽  
Mixing Techniques

Two critical factors that influence the accuracy of an impression include the proper manipulation of the impression materials and the technique used to make the impression. The purpose of this study was to clinically evaluate the effect of different mixing techniques on the accuracy of vinyl polysiloxane (VPS) impressions by assessing metal framework fit of fixed partial restorations. The study included 92 consecutive patients diagnosed with partial edentulism and treated with fixed partial denture restorations. The mixing technique was one of the two following mixing methods: hand mixing technique (45 patients), with the putty material mixed according to the manufacturer’s instructions; or mechanical mixing technique (47 patients), with the putty material mixed by a Pentamix device. Under both mixing methods, vinyl polysiloxane was used as the impression material. Two impression techniques were randomly used by the operators (One/Two-stage putty –wash impression techniques). The accuracy of the metal framework restorations was tested clinically and radiologically, resulting in significant statistical difference (p = 0.04) between different mixing techniques. The mechanical mixing produced more accurate restorations (metal framework misfit only in 14.9% of patients vs. hand mixing 31.1%). Regarding the impression techniques, the two-stage impression technique was found to be significantly more accurate (p = 0.04), resulting in 14.6% ill-fitted metal frameworks vs. 31.8%, in the one-stage technique. It can be concluded that mechanical mixing yields more accurate impressions leading to more accurate restorations, especially when combined with two-stage impression technique.

In-vivo evaluation of the effect of cyanoacrylate on prosthetic vascular graft infection – does cyanoacrylate increase the severity of infection?

VASA ◽  
2020 ◽  
Vol 49 (4) ◽  
pp. 281-284
Author(s):  
Atıf Yolgosteren ◽  
Gencehan Kumtepe ◽  
Melda Payaslioglu ◽  
Cuneyt Ozakin
Keyword(s):  
Vascular Graft ◽  
Graft Infection ◽  
Vascular Graft Infection ◽  
Group 4 ◽  
Significant Difference ◽  
Group 3 ◽  
Group 2 ◽  
Prosthetic Vascular Graft Infection ◽  
Group 1

Summary. Background: Prosthetic vascular graft infection (PVGI) is a complication with high mortality. Cyanoacrylate (CA) is an adhesive which has been used in a number of surgical procedures. In this in-vivo study, we aimed to evaluate the relationship between PVGI and CA. Materials and methods: Thirty-two rats were equally divided into four groups. Pouch was formed on back of rats until deep fascia. In group 1, vascular graft with polyethyleneterephthalate (PET) was placed into pouch. In group 2, MRSA strain with a density of 1 ml 0.5 MacFarland was injected into pouch. In group 3, 1 cm 2 vascular graft with PET piece was placed into pouch and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. In group 4, 1 cm 2 vascular graft with PET piece impregnated with N-butyl cyanoacrylate-based adhesive was placed and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. All rats were scarified in 96th hour, culture samples were taken where intervention was performed and were evaluated microbiologically. Bacteria reproducing in each group were numerically evaluated based on colony-forming unit (CFU/ml) and compared by taking their average. Results: MRSA reproduction of 0 CFU/ml in group 1, of 1410 CFU/ml in group 2, of 180 200 CFU/ml in group 3 and of 625 300 CFU/ml in group 4 was present. A statistically significant difference was present between group 1 and group 4 (p < 0.01), between group 2 and group 4 (p < 0.01), between group 3 and group 4 (p < 0.05). In terms of reproduction, no statistically significant difference was found in group 1, group 2, group 3 in themselves. Conclusions: We observed that the rate of infection increased in the cyanoacyrylate group where cyanoacrylate was used. We think that surgeon should be more careful in using CA in vascular surgery.

scholarly journals An In Vivo Confocal Microscopic Study of Corneal Nerve Morphology in Unilateral Keratoconus

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Natasha Kishore Pahuja ◽  
Rohit Shetty ◽  
Rudy M. M. A. Nuijts ◽  
Aarti Agrawal ◽  
Arkasubhra Ghosh ◽  
...  
Keyword(s):  
Nerve Fiber ◽  
Nerve Branch ◽  
Intergroup Comparison ◽  
Corneal Nerve ◽  
Group 3 ◽  
Group 2 ◽  
Branch Density ◽  
Corneal Nerve Morphology ◽  
Group 1

Purpose.To study the corneal nerve morphology and its importance in unilateral keratoconus.Materials and Methods.In this prospective cross-sectional study, 33 eyes of 33 patients with keratoconus in one eye (Group 3) were compared with the other normal eye of the same patients (Group 2) and 30 eyes of healthy patients (Group 1). All patients underwent detailed ophthalmic examination followed by topography with Pentacam HR and in vivo confocal microscopy (IVCM). Five images obtained with IVCM were analyzed using an automated CCmetrics software version 1.0 for changes in subbasal plexus of nerves.Results.Intergroup comparison showed statistically significant reduction in corneal nerve fiber density (CNFD) and length (CNFL) in Group 3 as compared to Group 1 (p<0.001andp=0.001, resp.) and Group 2 (p=0.01andp=0.02, resp.). Though corneal nerve fiber length, diameter, area, width, corneal nerve branch density, and corneal total branch density were found to be higher in decentered cones, only the corneal nerve branch density (CNBD) was found to be statistically significant (p<0.01) as compared to centered cones.Conclusion.Quantitative changes in the corneal nerve morphology can be used as an imaging marker for the early diagnosis of keratoconus before the onset of refractive or topography changes.

scholarly journals 173TRANSFER OF VITRIFIED BLASTOCYSTS FROM ONE OR TWO SUPEROVULATED LARGE WHITE HYPERPROLIFIC DONORS TO MEISHAN RECIPIENTS: REPRODUCTIVE PARAMETERS AT DAY 30 OF PREGNANCY

2004 ◽  
Vol 16 (2) ◽  
pp. 208
Author(s):  
C. Cuello ◽  
F. Berthelot ◽  
F. Martinat-Botté ◽  
P. Guillouet ◽  
V. Furstoss ◽  
...  
Keyword(s):  
Pregnancy Rate ◽  
Fisher Exact Test ◽  
Corpora Lutea ◽  
Large White ◽  
Embryo Survival ◽  
Exact Test ◽  
Group 2 ◽  
Fresh Semen ◽  
Group 1

The present study was designed to determine the effect of pooling embryos from two donors on the reproductive success of transfer of vitrified/warmed porcine blastocysts. Superovulated Large White hyperprolific gilts (n=24) were used as embryo donors. Gilts were artificially inseminated 12 and 24h after initial detection of estrus using fresh semen, and slaughtered on Days 5.5 to 6 of the estrous cycle (Day 0=Onset of estrus). Embryos were recovered by flushing the uterine horns, and unhatched blastocysts were selected. Vitrification and warming were performed as reported previously (Berthelot et al., 2000 Cryobiology 41, 116–124). Embryo transfers were conducted in asynchronous (−24h) Meishan gilts (n=20). Twenty vitrified/warmed blastocysts were surgically transferred into one uterine horn. Ten recipients received embryos from one donor (group 1) and the other ten transfers were performed with mixed embryos from two donors (group 2). Pregnancy was assessed ultrasonographically at Day 25 after estrus and recipients were slaughtered five days later. The pregnancy rate from the different groups was compared using Fisher exact test. The GLM procedure of SAS was used to determine the effect of the origin of embryos (one or two donors) on the number of developed fetuses and viable fetuses at Day 30 of pregnancy. The ovulation rate was 32.5±11.8 (mean±SD). The total number of embryos collected was 634, of which 57 (9.0%), 36 (5.7%), 513 (80.9%) and 28 (4.4%), were unfertilized oocytes and degenerated embryos, morulae, unhatched blastocysts and hatched blastocysts, respectively. The ratio of collected embryos to the number of corpora lutea was 81.3%. The pregnancy rate for group 1 (70%) was not different (P&gt;0.05) than that for group 2 (90%). No significant differences were detected between group 1 and group 2 for in vivo embryo development (number fetuses/transferred embryos in pregnant recipients; 33.3% v. 40%) or in vivo embryo survival (number viable fetuses/transferred embryos in pregnant recipients; 27.9% v. 33.9%). However, the in vivo efficiency (number viable fetuses/total transferred embryos) was higher (P&lt;0.05) when transfers were performed with embryos from two donors (19.5% v. 30.5%). These results indicate that pooling embryos from two donors increases the in vivo efficiency after transfer of vitrified/warmed porcine blastocysts. This study was supported by grant from SENECA (FPI/99, Spain).

scholarly journals Dynamics of intraocular temperature during local hypothermia (experimental study and mathematical modeling)

2019 ◽  
pp. 383-388
Author(s):  
Lukyan Anatychuk ◽  
Roman Kobyliansky ◽  
Nataliya Pasyechnikova ◽  
Volodymyr Naumenko ◽  
Oleg Zadorozhnyy ◽  
...  
Keyword(s):  
Mathematical Modeling ◽  
Mathematical Model ◽  
Biological Tissues ◽  
Comsol Multiphysics ◽  
Rabbit Eye ◽  
Local Contact ◽  
Group 2 ◽  
Local Hypothermia ◽  
Group 1

Therapeutic hypothermia currently is successfully in various fields of medicine to protect biological tissues from ischemia. However the issue of changes in intraocular temperature under hypothermia remains poorly understood. Purpose. To study the dynamics of intraocular temperature in conditions of local hypothermia and on the basis of the obtained data to develop a mathematical model of thermophysical processes in the rabbit eye. Materials and methods. An in vivo experiment was performed on 10 rabbits (20 eyes). In group 1 (5 rabbits, 10 eyes), epibulbar and intraocular temperature was measured after local contact hypothermia through closed eyelids, in group 2 (5 rabbits, 10 eyes) after local contact hypothermia directly through the cornea. ока безпосередньо через рогівку. Для гіпотермії застосовувався гелевий акумулятор холоду температурою -10 °С. Для вимірювання температури в різних відділах ока застосовувався термоелектричний пристрій, розроблений Інститутом термоелектрики НАН і МОН України та ДУ «Інститут очних хвороб і тканинної терапії ім. В. П.Філатова НАМН України». Для розробки математичної моделі теплофізичних процесів в оці кролика використано пакет прикладних програм COMSOL Multiphysics. Результати. Температура склоподібного тіла в 1-й і 2-й групі тварин знизилася в порівнянні з вихідними даними відповідно на 2,8 °С і 5,4 °С. Температурний градієнт між зовнішньою поверхнею рогівки і середньою частиною склоподібного тіла ока кролика в 1-й групі становив 7,1 °С, у 2-й групі – 9,2 °С. На підставі отриманих експериментальних даних було розроблено схематичну, математичну та комп’ютерну моделі ока кролика з урахуванням його теплофізичних особливостей, кровообігу, процесів метаболізму і теплообміну. Висновки. У разі локальної контактної гіпотермії очей кролика відбувається зниження епібульбарної температури і температури внутрішньоочних середовищ, як під час охолодження безпосередньо зовнішньої поверхні рогівки, так і під час впливу холоду через закриті повіки. Ключові слова: внутрішньоочна температура, локальна гіпотермія, око кролика, математична модель ока. Для цитування: Анатичук ЛІ, Пасєчнікова НВ, Науменко ВО, Задорожний ОС, Назаретян РЕ, Кобилянський РР, Верешко ЄЮ. Динаміка внутрішньоочної температури в умовах локальної гіпотермії (експериментальне дослідження та математичне моделювання). Журнал Національної академії медичних наук України. 2019;25(4):383–8

A TRIAL OF SUBCUTANEOUS VERSUS INTRAVENOUS ADMINISTRATION OF LOW MOLECULAR WEIGHT (LMW) HEPARIN AND UNFRACTIONATED (UF) HEPARIN IN THE TREATMENT OF ESTABLISHED DEEP VENOUS THROMBOSIS (DVT)

1987 ◽  
Author(s):  
C J Parker ◽  
D E Huber ◽  
A R Hedges ◽  
V V Kakkar
Keyword(s):  
Low Molecular Weight ◽  
Heparin Group ◽  
Expert Radiologist ◽  
Intravenous Heparin ◽  
Antithrombotic Effects ◽  
Group 3 ◽  
Group 2 ◽  
Efficacy Of Treatment ◽  
Group 1

In a randomized clinical trial of 100 patients, the in vivo antithrombotic effects of a subcutaneously administered LMW heparin fraction (CY216) used in the treatment of established DVT, was compared with UF heparin administered by either intravenous or subcutaneous routes.Venograms were used to make the initial diagnosis, and efficacy of treatment was assessed by a repeat venogram done on day 6. Comparison of the venograms were done blind by an expert radiologist.Patients were randomized to one of three groups: Group 1 received subcutaneous CY216; Group 2 received subcutaneous UF heparin: Group 3 received continuous intravenous UF heparin. Random patients from each group had detailed haematological tests consisting of twicedaily KCCT and anti-Xa levels. Extension of thrombus occurred in significantly morepatients receiving intravenous heparin than subcutaneous heparin (p-0.02).There was no difference between the two subcutaneousgroups. There were no haematological complications.We conclude that subcutaneous administratiyon of heparin is the treatment of choice in the treatment of DVT.

Micropuncture study of the effect of ANP on the papillary collecting duct in the rat

1988 ◽  
Vol 254 (4) ◽  
pp. F477-F483 ◽  
Author(s):  
A. van de Stolpe ◽  
R. L. Jamison
Keyword(s):  
Collecting Duct ◽  
Sodium Concentration ◽  
Sodium Reabsorption ◽  
Micropuncture Study ◽  
Papillary Collecting Duct ◽  
Group 3 ◽  
Group 2 ◽  
Tubule Fluid ◽  
Group 1

Micropuncture collections were obtained from the terminal collecting duct (CD) at base and tip of the renal papilla of the rat. Group 1 was studied before and during infusion with atrial natriuretic peptide (ANP), group 2 was administered the vehicle only, and group 3 received acetazolamide to increase sodium delivery to the base to a similar extent as after ANP. ANP caused a decrease in blood pressure, a slight increase in GFR, natriuresis, and diuresis. Sodium delivery to the collecting duct at the base of the papilla increased. Between base and tip, sodium reabsorption was inhibited. Tubule fluid sodium concentration (TFNa) was increased at the base and remained high at the tip; in contrast TFNa fell between base and tip in control and acetazolamide groups. After acetazolamide, sodium reabsorption in the terminal CD was not inhibited. These results demonstrate that in vivo ANP 1) increases the delivery of sodium to the terminal CD and 2) inhibits sodium reabsorption in the terminal CD. The findings for chloride were similar to those for sodium. ANP also increased delivery of H2O, K, Ca, and Mg to the CD at the papillary base but did not significantly affect their transport by the terminal CD.

Early Surgical Repair of Medial Meniscus Posterior Root Tear Minimizes the Progression of Meniscal Extrusion: 2-Year Follow-up of Clinical and Radiographic Parameters After Arthroscopic Transtibial Pull-out Repair

2020 ◽  
Vol 48 (11) ◽  
pp. 2692-2702 ◽  
Author(s):  
Hyun-Soo Moon ◽  
Chong-Hyuk Choi ◽  
Min Jung ◽  
Dae-Young Lee ◽  
Seung-Pyo Hong ◽  
...  
Keyword(s):  
Symptom Duration ◽  
Root Tear ◽  
Meniscal Extrusion ◽  
Factors Affecting ◽  
Preoperative Symptom ◽  
Pull Out ◽  
Radiographic Parameters ◽  
Group 2 ◽  
Relevant Factors ◽  
Group 1

Background: Conflicting results have been reported concerning the progression of medial meniscal extrusion (MME) after arthroscopic transtibial pull-out repair of medial meniscus posterior root tear (MMRT), and no study has evaluated the relevant factors affecting the progression of MME. Purpose: To (1) evaluate the subjective and objective surgical outcomes of arthroscopic transtibial pull-out repair of MMRT and (2) identify relevant factors affecting the progression of MME after surgery. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 63 patients who underwent isolated arthroscopic transtibial pull-out repair of MMRT between January 2010 and June 2017 were evaluated retrospectively. Clinical scores and various radiographic parameters were evaluated to assess the surgical outcomes. The patients were classified into 2 groups according to the change in medial meniscal extrusion ratio (MMER) at 1 year after surgery compared with before surgery (group 1 consisted of 21 patients with reduced or maintained MMER; group 2 consisted of 42 patients with increased MMER). Variables including baseline demographics, radiographic parameters, and arthroscopic findings were compared to identify relevant factors affecting the progression of MME after surgery. Results: In the overall cohort, clinical outcomes at postoperative 2 years improved significantly ( P < .001 for visual analog scale score, International Knee Documentation Committee subjective score, and Lysholm score), whereas radiographic parameters showed an overall deterioration compared with the preoperative level. In subgroup comparisons, a significant difference was seen in the time from the onset of symptoms until surgery ( P < .001), defined as preoperative symptom duration, which a subsequent logistic regression analysis revealed to be a relevant factor associated with the progression of MMER ( P = .015). Both groups showed progression of radiographic osteoarthritis, but the progression was significantly higher in group 2 compared with group 1 at postoperative 2 years ( P = .032). On receiver operating characteristic curve analysis, the cutoff point for preoperative symptom duration associated with the progression of MMER was 13 weeks (sensitivity, 52.4%; specificity, 76.2%; accuracy, 72.4%). Conclusion: The arthroscopic transtibial pull-out repair of MMRT showed clinical improvement but did not prevent the progression of knee osteoarthritis, MME, or MMER. Although the preservation of MMER was not capable of completely preventing the progression of knee degeneration, MMER still has a potential clinical value in delaying the rate of progression of knee degeneration. Early surgical repair of MMRT, within 13 weeks from the onset of symptoms, might be helpful to prevent the progression of MME.

scholarly journals How to Achieve Faster Osteotomy Healing and Prevent Refracture after Ulnar Shortening Osteotomy?

2020 ◽  
Author(s):  
Jong woo Kang ◽  
Soo Min Cha ◽  
Sang-gyun Kim ◽  
In Cheul Choi ◽  
Dong Hun Suh ◽  
...  
Keyword(s):  
Dynamic Compression ◽  
Factors Affecting ◽  
Ulnar Shortening Osteotomy ◽  
Ulnar Impaction ◽  
Shortening Osteotomy ◽  
Osteotomy Technique ◽  
Baseline Characteristics ◽  
Group 2 ◽  
Ulnar Impaction Syndrome ◽  
Group 1

Abstract Background: Parallel osteotomy is essential for favorable osteotomy reduction and healing and technically challenging during diaphyseal ulnar shortening osteotomy (USO). This study aimed to evaluate the advantages of guided osteotomy for parallel osteotomy and reduction osteotomies and healing over freehand osteotomy. It also aimed to identify surgical factors affecting healing after diaphyseal USO.Methods: Between June 2005 and March 2016, 136 wrists that had undergone diaphyseal USO for ulnar impaction syndrome (UIS) were evaluated. The wrists were divided into two groups according to the osteotomy technique (Group 1: freehand osteotomy, 74 wrists; Group 2: guided osteotomy, 62 wrists). The osteotomy reduction gap and time to osteotomy healing (union and consolidation) were compared between the groups. A multiple regression test was performed to identify the surgical factors affecting healing. The cut-off length of the reduction gap to achieve osteotomy union on time and the cut-off period to decide the failure of complete consolidation were statistically calculated. Results: The baseline characteristics were not different between the two groups. The osteotomy reduction gap, time to osteotomy union, and complete consolidation were shorter in Group 2 than in Group 1 (p=0.002, <0.001, 0.002). The osteotomy reduction gap was a critical surgical factor affecting both time to osteotomy union and complete consolidation (p<0.001, <0.001). The use of a dynamic compression plate affected only the time to complete consolidation (p<0.001). The cut-off length of the osteotomy reduction gap to achieve osteotomy union on time was 0.85 mm. The cut-off period to decide the failure of complete consolidation was 23.5 months after osteotomy.Conclusions The minimal osteotomy reduction gap was the most important for timely osteotomy healing in the healthy ulna and a guided osteotomy was beneficial to reducing the osteotomy reduction gap during USO.

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