scholarly journals Comparison of Polymerization Shrinkage, Physical Properties, and Marginal Adaptation of Flowable and Restorative Bulk Fill Resin-Based Composites

2017 ◽  
Vol 42 (4) ◽  
pp. 375-386 ◽  
Author(s):  
JH Jung ◽  
SH Park

SUMMARY Purpose: The purpose of this study was to compare the marginal adaptation of two flowable bulk fill resin-based composites (FB-RBCs), two restorative bulk fill resin-based composites (RB-RBCs), and one regular incremental-fill RBC in MOD cavities in vitro. Additionally, the influence of linear polymerization shrinkage, shrinkage force, flexural modulus, and bottom/top surface hardness ratio on the marginal adaptation was evaluated. Methods: A Class II MOD cavity was prepared in 40 extracted sound lower molars. In group 1 (control group), the preparation was filled with Filtek Z350 (Z3, 3M ESPE, St Paul, MN, USA) using the incremental filling technique. The FB-RBCs, SDR (SD, group 2) (Dentsply Caulk, Milford, DE, USA) and Venus Bulk Fill (VB, group 3) (Heraeus Kulzer, Dormagen, Germany), were placed in the core portion of the cavity first, and Z350 was filled in the remaining cavity. The RB-RBCs, Tetric N-Ceram Bulkfill (TB, group 4) (Ivoclar Vivadent, Schaan, Liechtenstein) and SonicFill (SF, Group 5) (Kerr, West Collins, Orange, CA, USA), were bulk filled into the preparation. Images of the magnified marginal area were captured under 100× magnification before and after thermomechanical loading, and the percentage ratio of the imperfect margin (%IMwhole) was calculated. Gaps, cracks in the enamel layer, and chipping of composite, enamel, or dentin were all considered to be imperfect margins. Linear polymerization shrinkage, polymerization shrinkage force, flexural strength, flexural modulus, and bottom/top surface hardness ratio of were measured. Eight specimens were allocated for each material for each test. One-way analysis of variance with the Scheffé test was used to compare the groups at a 95% confidence level. Results: Before thermomechanical loading, %IMwhole was in the order of group 3 ≤ groups 2 and 5 ≤ groups 1 and 4 (p=0.011), whereas after loading, it was in the order of group 4 ≤ group 5 ≤ group 1 ≤ groups 2 and 3 (p<0.001). The order of materials were Z3 < TB and SF < SD and VB (p<0.001) in polymerization shrinkage; SF ≤ TB ≤ Z3 < SD < VB (p<0.001) in polymerization shrinkage force; VB < SD < TB ≤ Z3 ≤ SF (p<0.001) in flexural modulus; SD, VB, and TB < Z3 and SF (p<0.001) in flexural strtength; and SF< Z3 < TB < VB and SD (p<0.001) in bottom/top surface hardness ratio. The Pearson correlation constant between %IMwhole and polymerization shrinkage, shrinkage force, elastic modulus, and bottom/top surface hardness ratio was 0.697, 0.708, −0.373, and 0.353, respectively, after thermomechanical loading. Conclusion: Within the limitations of this study, RB-RBCs showed better marginal adaptation than FB- RBCs. The lower level of polymerization shrinkage and polymerization shrinkage stress in RB-RBCs seems to contribute to this finding because it would induce less polymerization shrinkage force at the margin. FB-RBCs with lower flexural modulus may not provide an effective buffer to occlusal stress when they are capped with regular RBCs.

Author(s):  
P. Bagavandoss ◽  
JoAnne S. Richards ◽  
A. Rees Midgley

During follicular development in the mammalian ovary, several functional changes occur in the granulosa cells in response to steroid hormones and gonadotropins (1,2). In particular, marked changes in the content of membrane-associated receptors for the gonadotropins have been observed (1).We report here scanning electron microscope observations of morphological changes that occur on the granulosa cell surface in response to the administration of estradiol, human follicle stimulating hormone (hFSH), and human chorionic gonadotropin (hCG).Immature female rats that were hypophysectcmized on day 24 of age were treated in the following manner. Group 1: control groups were injected once a day with 0.1 ml phosphate buffered saline (PBS) for 3 days; group 2: estradiol (1.5 mg/0.2 ml propylene glycol) once a day for 3 days; group 3: estradiol for 3 days followed by 2 days of hFSH (1 μg/0.1 ml) twice daily, group 4: same as in group 3; group 5: same as in group 3 with a final injection of hCG (5 IU/0.1 ml) on the fifth day.


2019 ◽  
Vol 17 (4) ◽  
pp. 354-364
Author(s):  
Hassan Al-Thani ◽  
Moamena El-Matbouly ◽  
Maryam Al-Sulaiti ◽  
Noora Al-Thani ◽  
Mohammad Asim ◽  
...  

Background: We hypothesized that perioperative HbA1c influenced the pattern and outcomes of Lower Extremity Amputation (LEA). Methods: A retrospective analysis was conducted for all patients who underwent LEA between 2000 and 2013. Patients were categorized into 5 groups according to their perioperative HbA1c values [Group 1 (<6.5%), Group 2 (6.5-7.4%), Group 3 (7.5-8.4%), Group 4 (8.5-9.4%) and Group 5 (≥9.5%)]. We identified 848 patients with LEA; perioperative HbA1c levels were available in 547 cases (Group 1: 18.8%, Group 2: 17.7%, Group 3: 15.0%, Group 4: 13.5% and Group 5: 34.9%). Major amputation was performed in 35%, 32%, 22%, 10.8% and 13.6%, respectively. Results: The overall mortality was 36.5%; of that one quarter occurred during the index hospitalization. Mortality was higher in Group 1 (57.4%) compared with Groups 2-5 (46.9%, 38.3%, 36.1% and 31.2%, respectively, p=0.001). Cox regression analysis showed that poor glycemic control (Group 4 and 5) had lower risk of mortality post-LEA [hazard ratio 0.57 (95% CI 0.35-0.93) and hazard ratio 0.46 (95% CI 0.31-0.69)]; this mortality risk persisted even after adjustment for age and sex but was statistically insignificant. The rate of LEA was greater among poor glycemic control patients; however, the mortality was higher among patients with tight control. Conclusion: The effects of HbA1c on the immediate and long-term LEA outcomes and its therapeutic implications need further investigation.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yu Liu ◽  
Jing Li ◽  
Wanyu Zhang ◽  
Yihong Guo

AbstractOestradiol, an important hormone in follicular development and endometrial receptivity, is closely related to clinical outcomes of fresh in vitro fertilization-embryo transfer (IVF-ET) cycles. A supraphysiologic E2 level is inevitable during controlled ovarian hyper-stimulation (COH), and its effect on the outcome of IVF-ET is controversial. The aim of this retrospective study is to evaluate the association between elevated serum oestradiol (E2) levels on the day of human chorionic gonadotrophin (hCG) administration and neonatal birthweight after IVF-ET cycles. The data of 3659 infertile patients with fresh IVF-ET cycles were analysed retrospectively between August 2009 and February 2017 in First Hospital of Zhengzhou University. Patients were categorized by serum E2 levels on the day of hCG administration into six groups: group 1 (serum E2 levels ≤ 1000 pg/mL, n = 230), group 2 (serum E2 levels between 1001 and 2000 pg/mL, n = 524), group 3 (serum E2 levels between 2001 and 3000 pg/mL, n = 783), group 4 (serum E2 levels between 3001 and 4000 pg/mL, n = 721), group 5 (serum E2 levels between 4001 and 5000 pg/mL, n = 548 ), and group 6 (serum E2 levels > 5000 pg/mL, n = 852). Univariate linear regression was used to evaluate the independent correlation between each factor and outcome index. Multiple logistic regression was used to adjust for confounding factors. The LBW rates were as follows: 3.0% (group 1), 2.9% (group 2), 1.9% (group 3), 2.9% (group 4), 2.9% (group 5), and 2.0% (group 6) (P = 0.629), respectively. There were no statistically significant differences in the incidences of neonatal LBW among the six groups. We did not detect an association between peak serum E2 level during ovarian stimulation and neonatal birthweight after IVF-ET. The results of this retrospective cohort study showed that serum E2 peak levels during ovarian stimulation were not associated with birth weight during IVF cycles. In addition, no association was found between higher E2 levels and increased LBW risk. Our observations suggest that the hyper-oestrogenic milieu during COS does not seem to have adverse effects on the birthweight of offspring after IVF. Although this study provides some reference, the obstetric-related factors were not included due to historical reasons. The impact of the high estrogen environment during COS on the birth weight of IVF offspring still needs future research.


1997 ◽  
Vol 65 (2) ◽  
pp. 267-273 ◽  
Author(s):  
I. A. Forsyth ◽  
F. E. Gebbie ◽  
J. Arendt

AbstractTo avoid winter scarcity of fresh goat milk, simple methods of advancing the season of kidding would be commercially valuable. A combination of long-day light treatment followed by melatonin is successful but other aspects of seasonality including coat growth are also reset. To investigate whether effects on breeding season and coat growth can be dissociated, British Saanen dairy goats (no. = 30) were randomly allocated to one of six groups. Control goats were untreated. Goats in the other five groups received 2 months of treatment with 20 h light: 4 h darkness (20L: 4D) and were then given 3 mg melatonin orally at 16.00 hfor 2 months. The treatments started on 11 January (group 1), 29 March (group 2), 14 June (group 3), 30 August (group 4) and 8 November (group 5). Weekly blood samples were taken for the measurement of progesterone to monitor ovarian activity and prolactin. Side patches (10 cm ×10 cm) were clipped monthly from alternate sides and weighed to measure coat growth. The onset of ovarian activity was advanced from a median date of 15 November in controls to 24 May in group 1 (P < 0·01), 16 August in group 2 (P < 0·05) and 18 October in group 3 (? < 0·05). Groups 4 and 5 showed no significant change in the onset of oestrus (median onset dates 8 November and 1 November, respectively). Group 1 goats came into season again with controls in November. In all except group 5, treatment interacted with time to affect significantly the growth of the coat. The pattern of coat growth was most altered (P < 0·001) in groups 1 and 2. This was associated with effects on plasma prolactin concentrations of light stimulation and melatonin suppression. Group 1 goats resynchronized with control goats to show a coat of normal weight in the winter following treatment. Division of milking goat herds into spring and autumn kidding groups is, therefore, a practical possibility, but effects on overall milk yield require study.


1984 ◽  
Vol 64 (1) ◽  
pp. 39-43 ◽  
Author(s):  
L. E. JEREMIAH ◽  
G. M. WEISS

A total of 130 barrows and 113 gilts were slaughtered over a range of liveweights from 65.6 to 143.9 kg. These animals were randomly assigned to six different liveweight groups (group 1, less than 79.5 kg; group 2, 79.5 through 93.1 kg; group 3, 93.2 through 106.7 kg; group 4, 106.8 through 120.4 kg; group 5, 120.5 through 134.0 kg; and group 6, 134.1 kg and over) and utilized to evaluate the effects of slaughter weight and sex on palatability and cooking properties. The composite results indicated that the slaughter weight of both barrows and gilts can, from a practical standpoint, be increased to take advantage of potential economic advantages without meaningfully altering cooking losses or palatability attributes. Key words: Pork, slaughter weight, sex, palatability, cooking losses


Kavkazologiya ◽  
2021 ◽  
pp. 12-25
Author(s):  
S.M. OSTASHINSKIJ ◽  
◽  
M.A. KULKOVA ◽  

The article presents the results of petrographic analysis of the ceramics of the Chalcolithic settlement of Meshoko. A total of 42 fragments were examined (see appendix), 10 of which belong to the upper part of the monument's sediments (layers 1 and 2a; Fig. 1), 20 refer to the middle part of the sediments (layer 2b; Fig. 2), 12 – to the lower part (layer 3; Fig. 3). Based on the analysis, 5 groups of ceramics were identified (Fig. 4). Group 1 consists of fragments with an admixture of limestone, group 2 – with an admixture of diorite, group 3 – with an admixture of biogenic carbonates and sand, group 4 – with an admixture of calcite, group 5 – with an admixture of diorite and chamotte. Clays of smectite composition predominate in groups 1 and 2, while clays of smectite-carbonate composition predominate in groups 3 and 4. Comparison of these groups with stratigraphy revealed that most of the ceramics of groups 3 and 4 are confined to the lower layer, and groups 1 and 2 to the middle and upper layer (Table 1). In addition, the ceramics of these layers differ in the nature of the external surface treatment. Significant changes in the technology of making ceramics during the transition from the lower layer to the middle layer allow us to assume corresponding changes in the composition of the population.


2018 ◽  
Vol 32 (4) ◽  
pp. 163
Author(s):  
Fábio Herrmann Coelho-de-Souza ◽  
Guilherme Fossá ◽  
Flávia Ávila Pereira ◽  
Celso Afonso Klein-Júnior ◽  
Maria Carolina Guilherme Erhardt ◽  
...  

OBJECTIVE: This study evaluated in vitro the shear bond strength of experimentally fractured human tooth fragments reattached with different adhesive materials and retentive techniques.METHODS: Forty-eight sound mandibular incisors were randomly divided into 6 groups (n=8). Their incisal edges were cut off in 5 groups, representing an enamel-dentin fracture. Intact teeth were used as control (Group 1). The fragment edges were reattached with adhesive system (Scotch Bond Multipurpose – 3M ESPE) (Group 2), adhesive system and composite resin (ICE – SDI) (Group 3), adhesive system and composite resin with circumferential bevel (Group 4), adhesive system and composite resin with internal dentin groove (Group 5), and adhesive system and composite resin with the circumferential bevel and internal dentin groove (Group 6). Shear bond strength was determined in a universal testing machine. Fracture modes were identified by light microscope. Kruskal-Wallis was used to analysis resistance to fracture and fracture patterns.RESULTS: The results showed statistically significant differences (p<0.05) among groups. The intact teeth (Group 1) showed higher fracture resistance than the other groups. Groups 2 and 6 did not differ and were statistically superior to other techniques. Group 4 presented statistically higher than in Group 5, which in turn was more resistant than Group 3.CONCLUSIONS: None of the fragment reattachment techniques was able to achieve the strength of sound teeth. Fragments reattached only with adhesive system or with adhesive system and composite resin with the circumferential bevel and internal dentin groove showed the best performance for resistance to fracture.


2012 ◽  
Vol 6 (6) ◽  
pp. 234 ◽  
Author(s):  
Ugur Kuyumcuoglu ◽  
Bilal Eryildirim ◽  
Murat Tuncer ◽  
Gokhan Faydaci ◽  
Fatih Tarhan ◽  
...  

Background: We investigated whether the frequency of lower urinary tract symptoms (LUTS) increased in patients in whom double-J stents were applied. We also evaluated several medical therapy protocols to treat symptoms related with ureteral stents.Materials and Methods: A total of 108 patients, in whom unilateral double-j stent was applied during ureteral stone treatment, were included. Before the double-J stent was applied, all patients completed storage components of the “International Prostate Symptom Score” (IPSSs), quality of life components of the IPSS (IPSS-QOL) and “Overactive Bladder Questionnaire” (OABq) forms and scores were calculated. After the procedure, cases were randomized into 5 groups, an antiinflammatory was given to Group 1, spasmolytic to Group 2, anticholinergic to Group 3 and α-blocker to Group 4. No additional drug was given to Group 5 as this control group. During the fourth week of the procedure, IPSSs, IPSS-QOL and OABq forms were again completed and scores were compared with the previous ones.Results: When all the cases were evaluated, the IPSSs, IPSS-QOLand OABq scores of patients in whom the double-J stent was applied were statistically significantly higher the procedure. Compared to the control group, the cases where the double-J stent was applied showed a higher IPSSs, IPSS-QOL and OABq scores and none of the medical therapies could prevent this increase.Interpretation: The frequency of LUTS increased in cases where the ureteral stent was applied and discomfort continued as long as the stent stayed in the body.


Author(s):  
Yogi Ramdani, Erwanto, Farida Fathul, dan Liman

This study aimed to investigate the effect of adding multi nutrient sauce to rations on the digestibility of dry matter and organic matter in sheep. This research was conducted in May--July 2019 in Kebagusan Village, Gedong Tataan District, Pesawaran Regency. Analysis of feed ingredients and feces was carried out at the Animal Nutrition and Feed Laboratory, Department of Animal Husbandry, Faculty of Agriculture, University of Lampung. This research was conducted experimentally using the Randomized Block Design (RBD) method. Sheep were divided into six groups based on body weight, namely group 1 (11,18--13,18 kg), group 2 (13,97--14,13 kg), group 3 (14,31--14,51 kg), group 4 (14,89--15,91 kg), group 5 (16,35--16,66 kg), and group 6 (17,15--17,77 kg). Each group consisted of 3 sheep. Treatment given were R0: basal ration formulated by farmer (forage silage + cassava byproduct), R1: R0 + 5% multi nutrient sauce, R2: R0 + 10% multi nutrient sauce. The results showed that the addition of 10% multi nutrient sauce was the best treatment that could improve the digestibility of dry matter and organic matter in sheep.   Key word : Multi nutrient sauce, Dry matter digestibility, Digestibility of organic matter, Sheep.


2020 ◽  
Vol 11 (1) ◽  
pp. 280-284 ◽  
Author(s):  
Julietpoornamathy J ◽  
Parameswari C.S.

In medical sciences, toxicity is an area wherein extensive studies have been carried to improve the diseases as well as to prevent. So, there is a high requirement for novel and improved alternative therapeutic strategies to manage diseases. The liver is the largest gland in the body, which executes several important mechanisms; it stores minerals and vitamins and releases them in periods of need. The main aim of this study was to give a closer insight into potent non- toxic compounds that is capable of modifying the responses. Animals were divided into five equal groups viz control (Group 1), administered with food and water ad libitum, (Group 2) administered with olive oil, (Group 3) administered with zingerone, (Group 4) administered with concanavalin A, (Group 5) administered with cyclosporine A followed by zingerone. Our results revealed significant changes in liver marker enzymes and liver histology of zingerone treated rats when compared to control rats.  A corollary, zingerone has no toxic effect on hepatocytes and was found to be safe at a dose of 10mg/kg b wt and also ameliorates hepatotoxicity.


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