scholarly journals Evaluation of Extraradicular Diffusion of Hydrogen Peroxide during Intracoronal Bleaching Using Different Bleaching Agents

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Mohammad E. Rokaya ◽  
Khaled Beshr ◽  
Abeer Hashem Mahram ◽  
Samah Samir Pedir ◽  
Kusai Baroudi
Keyword(s):  
Hydrogen Peroxide ◽  
Sodium Perborate ◽  
Water Mixture ◽  
Carbamide Peroxide ◽  
Group 4 ◽  
Group 3 ◽  
Group 2 ◽  
Materials Used ◽  
Diffusion Of Hydrogen ◽  
Group 1

Objectives. Extra radicular diffusion of hydrogen peroxide associated with intracoronal teeth bleaching was evaluated.Methods. 108 intact single rooted extracted mandibular first premolars teeth were selected. The teeth were instrumented with WaveOne system and obturated with gutta percha and divided into four groups (n=27) according to the bleaching materials used. Each main group was divided into three subgroups (n=9) according to the time of extra radicular hydrogen peroxide diffusion measurements at 1, 7, and 14 days: group 1 (35% hydrogen peroxide), group 2 (35% carbamide peroxide), group 3 (sodium perborate-30% hydrogen peroxide mixture), and group 4 (sodium perborate-water mixture). Four cemental dentinal defects were prepared just below the CEJ on each root surface. The amount of hydrogen peroxide that leached out was evaluated after 1, 7, and 14 days by spectrophotometer analysis. The results were analyzed using the ANOVA and Tukey’s test.Results. Group 1 showed highest extra radicular diffusion, followed by group 3 and group 2, while group 4 showed the lowest mean extra radicular diffusion.Conclusion. Carbamide peroxide and sodium perborate-water mixture are the most suitable bleaching materials used for internal bleaching due to their low extra radicular diffusion of hydrogen peroxide.

scholarly journals Microbial Leakage of Enterococcus Faecalis of Temporary Restorative Materials in Endodontic Treatment

2015 ◽  
pp. 125
Author(s):  
José Pablo Meneses Guzmán ◽  
Evelyn Loaiza Azofeifa
Keyword(s):  
Enterococcus Faecalis ◽  
Bromocresol Purple ◽  
Group 4 ◽  
Significant Difference ◽  
Restorative Materials ◽  
Group 3 ◽  
Group 2 ◽  
Materials Used ◽  
Negative Controls ◽  
Group 1

<p><span>The aim of this study was to determine whether there is any significant difference in average days of Enterococcus faecalis microleakage through the coronal seal of four temporary restorative materials used in endodontics , Cavit® (3M), Duotemp® (Coltène), Clip® (VOCO) y Cimpat L.C® (Septodont). Ninety caries free extracted human premolars were randomly divided into 4 groups after the coronal access preparation; Group 1. Cavit® , Group 2 Duotemp® , Group 3. Clip , Group 4 Cimpat and controls were not restored with any material. Each group were mounted in 24 sterile well plates. Each well contained 2 ml of broth with bromocresol purple indicator 1% glucose. All Samples, except negative controls, were inoculated with E. faecalis in saline 0.85% 10 ^ 6 U / ml. The groups were observed daily for 30 days to detect changes in the indicator color from purple to yellow. ®. Jonckheere-Terpstra test was used with a 95% of confidence. The average days Filtration of materials was 12.50 for Clip®, 12.83 for Cavit®, 13.44 for DuoTemp® and 14.44 for Cimpat LC®. The temporary restorative materials studied shows microbial leakage after 15 days. </span></p>

scholarly journals The effect of tooth bleaching on the shear bond strength of orthodontic brackets using self-etching primer systems

2013 ◽  
Vol 07 (01) ◽  
pp. 055-060 ◽  
Author(s):  
Mehmet Akin ◽  
Sertac Aksakalli ◽  
Faruk Ayhan Basciftci ◽  
Abdullah Demir
Keyword(s):  
Hydrogen Peroxide ◽  
Bond Strength ◽  
Shear Bond Strength ◽  
Orthodontic Brackets ◽  
Control Group ◽  
Carbamide Peroxide ◽  
Peroxide Bleaching ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

ABSTRACTObjective: The purpose of this study was to determine the effect of 10% carbamide peroxide and 38% hydrogen peroxide bleaching agents on the shear bond strength of orthodontic brackets using self-etching primer systems.Methods: Forty five freshly extracted human premolar teeth were randomly divided into 3 groups of 15 teeth each: control (group 1), 10% carbamide peroxide at-home bleached (group 2), and 38% hydrogen peroxide in-office bleached (group 3). Three weeks later, all brackets were bonded using a self-etching primer system. The shear bond strength of these brackets was measured and recorded in MPa. Adhesive remnant index (ARI) scores were determined after the brackets failed. Data were analyzed using Kruskal- Wallis test, pairwise comparisons were made using the Mann-Whitney U test and ARI scores were analyzed using a chi-square test at a significance level of P<.05.Results: The shear bond strengths of group 1 (mean: 17.7 ± 9.7 MPa) were significantly higher (P<.05) than those of group 3 (mean: 9.9 ± 5.4 MPa). No significant differences were found between group 2 (mean: 12.3 ± 4.7) and either group 1 or group 3 (P>.05). ARI scores did not differ significantly among the 3 groups.Conclusions: The use of 10% carbamide peroxide bleaching does not significantly reduce shear bond strength values. In contrast, use of 38% hydrogen peroxide bleaching significantly reduces these values. (Eur J Dent 2013;7:55-60)

scholarly journals Influence of bleaching and desensitizing gel on bond strength of orthodontic brackets

2015 ◽  
Vol 20 (2) ◽  
pp. 49-54 ◽  
Author(s):  
Fernanda Alves Rodrigues Britto ◽  
Adriana Simoni Lucato ◽  
Heloisa Cristina Valdrighi ◽  
Sílvia Amélia Scudeler Vedovello
Keyword(s):  
Hydrogen Peroxide ◽  
Bond Strength ◽  
Group 4 ◽  
Adhesive Remnant Index ◽  
Significant Difference ◽  
Group 3 ◽  
Group 5 ◽  
Group 2 ◽  
Bovine Enamel ◽  
Group 1

OBJECTIVE: The objective of this study was to assess, in vitro, the influence of bleaching gel and the use of desensitizing agent over bond strength of ceramic brackets bonded to bovine enamel. METHODS: One hundred bovine incisors were selected and randomly divided into five groups (n = 20): Group 1, control group (without bleaching); Group 2, bleached with 35% hydrogen peroxide; Group 3, bleached with 35% hydrogen peroxide (three applications, 15 minutes each) and desensitizing agent applied for 10 minutes; Group 4, bleached with 35% hydrogen peroxide for 40 minutes; Group 5, bleached with 35% hydrogen peroxide for 40 minutes with desensitizing agent applied for 10 minutes. Brackets were bonded 7 days after bleaching and submitted to shear bond strength test after 24 hours at a compression rate of 1 mm/minute. After fracture, the adhesive remnant index (ARI) was assessed under stereoscopic at 40 x magnification. Shear strength data (MPa) were submitted to one-way ANOVA and Tukey's test with significance level set at 5%. RESULTS: Group 5 (29.33 MPa) showed significantly higher bond strength than Group 1 (19.19 MPa), Group 2 (20.59 MPa) and Group 4 (23.25 MPa), but with no difference in comparison to Group 3. There was no significant difference among the other groups. The adhesive remnant index showed predominance of score 3, that is, all resin remained adhered to enamel for all groups. CONCLUSION: Bleaching with 35% hydrogen peroxide with calcium associated with desensitizing agent application produced higher bond strength values of brackets bonded to bovine enamel.

scholarly journals Bond Strength of Metallic Brackets After Dental Bleaching

2009 ◽  
Vol 79 (1) ◽  
pp. 122-126 ◽  
Author(s):  
Virna Cavalcante Patusco ◽  
Gil Montenegro ◽  
Marcos Augusto Lenza ◽  
Adilson Alves de Carvalho
Keyword(s):  
Hydrogen Peroxide ◽  
Bond Strength ◽  
Shear Bond Strength ◽  
Tooth Surface ◽  
Carbamide Peroxide ◽  
Peroxide Bleaching ◽  
Group 3 ◽  
Group 2 ◽  
Group 1 ◽  
At Home

Abstract Objective: To test the hypothesis that there is no difference between the action of at-home and in-office vital bleaching on the shear bond strength of metallic brackets bonded with composite resin 24 hours after bleaching. Materials and Methods: Forty-five human upper premolars were randomly divided into three groups: (1) control, (2) 10% carbamide peroxide at-home bleached, and (3) 35% hydrogen peroxide in-office bleached. Twenty-four hours after bleaching the teeth were pumiced, bonded with metallic brackets, and stored in distilled water. One day after bonding the shear bond strength of the brackets was determined. Results: The mean shear bond strength of Group 1 (control) and Group 2 (carbamide peroxide bleached) were not statistically different. Group 3 (hydrogen peroxide bleached) had a significantly lower mean shear bond strength than Group 1 and Group 2. Conclusions: The hypothesis is rejected. Use of 10% carbamide peroxide bleaching does not significantly alter shear bond strength values. On the other hand, use of 35% hydrogen peroxide bleaching significantly reduces these values and diminishes the amount of resin remnant on the tooth surface after bracket debonding.

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.

Does Perioperative Hemoglobin A1c Level Affect the Incidence, Pattern and Mortality of Lower Extremity Amputation?

2019 ◽  
Vol 17 (4) ◽  
pp. 354-364
Author(s):  
Hassan Al-Thani ◽  
Moamena El-Matbouly ◽  
Maryam Al-Sulaiti ◽  
Noora Al-Thani ◽  
Mohammad Asim ◽  
...  
Keyword(s):  
Glycemic Control ◽  
Lower Extremity ◽  
Hazard Ratio ◽  
Lower Extremity Amputation ◽  
Group 4 ◽  
Group 3 ◽  
Group 5 ◽  
Group 2 ◽  
Extremity Amputation ◽  
Group 1

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.

Association between cervical disc disease and lesions of multiple sclerosis

2021 ◽  
pp. 197140092098356
Author(s):  
Marwan Alkrenawi ◽  
Michael Osherov ◽  
Azaria Simonovich ◽  
Jonathan Droujin ◽  
Ron Milo ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Cervical Disc ◽  
Cervical Disc Disease ◽  
Disc Disease ◽  
Group 4 ◽  
Demyelinating Lesions ◽  
Grade Ii ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

Background Cervical discopathy and demyelinating lesions often co-exist in patients with multiple sclerosis (MS). Our study examines the possible association between these two pathologies. Methods Medical records and cervical magnetic resonance imaging scans of MS patients with cervical discopathy who were seen at our MS clinic during 2018 were retrospectively reviewed. The severity of the disc disease was classified as grade I (no compression), grade II (compression of the dural sac) and grade III (cord compression). The spinal cord in each scan was divided into six segments corresponding to the intervertebral space of the spine (C1–C6). Each segment was defined as containing demyelinating lesion and disc pathology (group 1), demyelinating lesion without disc pathology (group 2), disc pathology without demyelinating lesion (group 3) and no demyelinating lesion or disc pathology (group 4). Fisher’s exact test was used to test the association between demyelinating lesions and disc pathology. Results Thirty-four MS patients with cervical discopathy were included in the study (26 females; average age 42.9 ± 13.7 years; average disease duration 8.4 ± 5.4 years). A total of 204 spinal cord segments were evaluated. Twenty-four segments were classified as group 1, 27 segments as group 2, 52 segments as group 3 and 101 segments as group 4. There was no association between demyelinating lesions and the grade of disc disease ( p = 0.1 for grade I, p = 0.3 for grade II and p = 1 for grade III disc disease). Conclusion Our study did not find any association between cervical disc disease and demyelinating spinal cord lesion.

scholarly journals Association between serum oestradiol level on the hCG administration day and neonatal birthweight after IVF-ET among 3659 singleton live births

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yu Liu ◽  
Jing Li ◽  
Wanyu Zhang ◽  
Yihong Guo
Keyword(s):  
Birth Weight ◽  
Ovarian Stimulation ◽  
Group 4 ◽  
Group 6 ◽  
Group 3 ◽  
Group 5 ◽  
Group 2 ◽  
The Impact ◽  
Ivf Et ◽  
Group 1

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.

scholarly journals Control of Vulval Competence and Centering in the Nematode Oscheius sp. 1 CEW1

Genetics ◽  
2003 ◽  
Vol 163 (1) ◽  
pp. 133-146 ◽  
Author(s):  
Sophie Louvet-Vallée ◽  
Irina Kolotuev ◽  
Benjamin Podbilewicz ◽  
Marie-Anne Félix
Keyword(s):  
Germ Line ◽  
Specific Mechanism ◽  
C Elegans ◽  
Group 4 ◽  
Cell Ablation ◽  
Group 3 ◽  
Group 2 ◽  
P Cells ◽  
Large Category ◽  
Group 1

Abstract To compare vulva development mechanisms in the nematode Oscheius sp. 1 to those known in Caenorhabditis elegans, we performed a genetic screen for vulva mutants in Oscheius sp. 1 CEW1. Here we present one large category of mutations that we call cov, which affect the specification of the Pn.p ventral epidermal cells along the antero-posterior axis. The Pn.p cells are numbered from 1 to 12 from anterior to posterior. In wild-type Oscheius sp. 1 CEW1, the P(4-8).p cells are competent to form the vulva and the progeny of P(5-7).p actually form the vulva, with the descendants of P6.p adopting a central vulval fate. Among the 17 mutations (defining 13 genes) that we characterize here, group 1 mutations completely or partially abolish P(4-8).p competence, and this correlates with early fusion of the Pn.p cells to the epidermal syncytium. In this group, we found a putative null mutation in the lin-39 HOM-C homolog, the associated phenotype of which could be weakly mimicked by injection of a morpholino against Osp1-lin-39 in the mother’s germ line. Using cell ablation in a partially penetrant competence mutant, we show that vulval competence is partially controlled by a gonadal signal. Most other mutants found in the screen display phenotypes unknown in C. elegans. Group 2 mutants show a partial penetrance of Pn.p competence loss and an abnormal centering of the vulva on P5.p, suggesting that these two processes are coregulated by the same pathway in Oscheius sp. 1. Group 3 mutants display an enlarged competence group that includes P3.p, thus demonstrating the existence of a specific mechanism inhibiting P3.p competence. Group 4 mutants display an abnormal centering of the vulval pattern on P7.p and suggest that a specific mechanism centers the vulval pattern on a single Pn.p cell.

scholarly journals Hypertrophy of unaffected cardiomyocytes correlates with severity of cardiomyopathy in female patients with Fabry disease

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Cristina Chimenti ◽  
Romina Verardo ◽  
Andrea Frustaci
Keyword(s):  
Fabry Disease ◽  
Wall Thickness ◽  
Left Ventricular ◽  
Female Patients ◽  
Maximal Wall Thickness ◽  
Group 4 ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

Abstract Aim To investigate the contribution of unaffected cardiomyocytes in Fabry disease cardiomyopathy. Findings Left ventricular (LV) endomyocardial biopsies from twenty-four females (mean age 53 ± 11 ys) with Fabry disease cardiomyopathy were studied. Diagnosis of FD was based on the presence of pathogenic GLA mutation, Patients were divided in four groups according with LV maximal wall thickness (MWT): group 1 MWT ≤ 10.5 mm, group 2 MWT 10.5–15 mm, group 3 MWT 16–20 mm, group 4 MWT > 20 mm. At histology mosaic of affected and unaffected cardiomyocytes was documented. Unaffected myocytes’ size ranged from normal to severe hypertrophy. Hypertrophy of unaffected cardiomyocytes correlated with severity of MWT (p < 0.0001, Sperman r 0,95). Hypertrophy of unaffected myocytes appear to concur to progression and severity of FDCM. It is likely a paracrine role from neighboring affected myocytes.

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