scholarly journals A comparative study between the effect of reverse curve of Spee archwires and anterior bite turbos in the treatment of deep overbite cases: A randomized clinical trial

2021 ◽  
Author(s):  
Ekram M. Al-Zoubi ◽  
Kazem S. Al-Nimri

ABSTRACT Objectives To compare deep overbite treatment using 0.016 × 0.022 nickel-titanium lower reverse curve of Spee archwire (LRCA) or metal anterior bite turbos (ABTs). Materials and Methods 48 patients with deep overbite malocclusion were randomly allocated into two groups. Group I (age = 18.4 ± 2.8 years, overbite = 5.8 ± 0.6 mm) was treated with LRCA, while Group II (age = 18.2 ± 3.1 years, overbite = 5.2 ± 0.4 mm) was treated with ABTs bonded to the palatal surface of the upper central incisors. Two cephalograms were taken for each patient, at post-alignment stage (T1) and post-leveling stage (T2). The primary outcomes were the anteroposterior and vertical changes of the lower teeth. The secondary outcomes were the effect on upper incisor inclination and the vertical linear changes of upper teeth, to assess the sagittal and vertical skeletal changes, and to compare the duration of overbite correction. Results 42 of the 48 patients recruited completed the study (21 in each group). At T2, the lower incisors proclined more in Group I (P ≤ .001). Both lower second molars (P ≤ .001) and lower first molars (P = .001) tipped more distally, while the lower first premolar tipped more mesially, in Group I (P < .05). All cusps of both lower molars showed more extrusion in Group II (P < .05) except for the mesial cusp of lower second molars (P = .095). The duration of overbite correction was shorter using the ABTs by 1.7 months (4.85 ± 1.56 and 3.15 ± 0.93 months for Group I and Group II, respectively). Conclusions LRCA causes lower incisor proclination with distal tipping of lower molars, while ABTs result in lower posterior tooth extrusion.

2020 ◽  
Vol 29 (04) ◽  
pp. 246-248
Author(s):  
Huma Sarwar ◽  
◽  
Meshal M Meshal M Naeem ◽  
Sumaiya Shabbir ◽  
Sania Riaz ◽  
...  

OBJECTIVE: To investigate the effect of nickel titanium rotary endodontic file immersion in hydrogen peroxide on cyclic fatigue resistance. METHODOLOGY: Twenty Six Protaper Universal (Dentsply Maillerfier) F1 files were randomly divided into two experimental groups. In Group I, Protaper universal variable taper F1 files were immersed in normal saline where as in Group II, the files were soaked in hydrogen peroxide (6% w/v) for 2 hours at 37°C. Cyclic fatigue of each file was checked by recording the number of rotations required to break a file in a 90°curve with a 5 mm radius. For statistical analysis of data, Two-way ANOVA was applied. A p value of <0.05 was considered significant. RESULT: Out of Twenty Six, Six files fractured spontaneously after immersion in hydrogen peroxide. Twenty files were subjected to fracture resistance testing. Statistically significant difference in cyclic fatigue resistace between the two groups was found (p=0.002). The files soaked in Group II required less revolutions to fracture than the ones immersed Group I. CONCLUSION: The immersion of NiTi endodontic files in hydrogen peroxide significantly reduces cyclic fatigue resistance. Therefore, immersion of the NiTi endodontic files in hydrogen peroxide solution for removal of clogged debris should be discouraged. KEYWORDS: Cyclic fatigue, Endodontic instruments, Hydrogen peroxide, NiTi HOW TO CITE: Sarwar H, Naeem MM, Shabbir S, Riaz S, Afaq H, Shabbir J. Effect of hydrogen peroxide on cyclic fatigue resistance of NiTi endodontic files. J Pak Dent Assoc 2020;29(4):246-248.


2006 ◽  
Vol 17 (2) ◽  
pp. 139-143 ◽  
Author(s):  
Carlos Eduardo da Silveira Bueno ◽  
Maraisa Greggio Delboni ◽  
Roberta Aranha de Araújo ◽  
Hilton José Carrara ◽  
Rodrigo Sanches Cunha

The purpose of this study was to assess in vitro the efficacy of nickel-titanium K³ rotary files and hand files for removal of gutta-percha and sealer from obturated root canals using either chloroform or chlorhexidine as solvents. Sixty extracted single-rooted bovine teeth with straight, large canals were prepared, obtured and randomly assigned to 3 groups (n=20). The teeth were stored at 37ºC for 1 month and then the gutta-percha and sealer were removed using different techniques, as follows. Group I: size 3 Gates-Glidden drills plus size 30 hand K-files and Hedström files and chloroform; Group II: K³ NiTi rotary files and chloroform; and Group III: K³ NiTi rotary files and 2% chlorhexidine gel. Radiographs were taken and scanned and the images were digitized. The total area of the canal and the area with remaining obturation material were measured in millimeters using a computed image analysis system (ImageLab). Data were analyzed statistically by one-way ANOVA and Tukey test at 5% significance level. The groups differed statistically (p<0.05) with respect to the average percentage of remaining gutta-percha and sealer, presenting the following sequence of effectiveness (from most to least effective): Group I (15.48%), Group II (28.42%) and Group III (35.96%). The findings of this study showed that, despite the technique used for removal of filling material, none of the retreated canals were completely free of gutta-percha and sealer remnants. The use of stainless steel hand files resulted in a lesser amount of filling debris than the use of nickel-titanium rotary instruments.


Author(s):  
K.K. SEKHRI ◽  
C.S. ALEXANDER ◽  
H.T. NAGASAWA

C57BL male mice (Jackson Lab., Bar Harbor, Maine) weighing about 18 gms were randomly divided into three groups: group I was fed sweetened liquid alcohol diet (modified Schenkl) in which 36% of the calories were derived from alcohol; group II was maintained on a similar diet but alcohol was isocalorically substituted by sucrose; group III was fed regular mouse chow ad lib for five months. Liver and heart tissues were fixed in 2.5% cacodylate buffered glutaraldehyde, post-fixed in 2% osmium tetroxide and embedded in Epon-araldite.


1998 ◽  
Vol 80 (09) ◽  
pp. 393-398 ◽  
Author(s):  
V. Regnault ◽  
E. Hachulla ◽  
L. Darnige ◽  
B. Roussel ◽  
J. C. Bensa ◽  
...  

SummaryMost anticardiolipin antibodies (ACA) associated with antiphospholipid syndrome (APS) are directed against epitopes expressed on β2-glycoprotein I (β2GPI). Despite a good correlation between standard ACA assays and those using purified human β2GPI as the sole antigen, some sera from APS patients only react in the latter. This is indicative of heterogeneity in anti-β2GPI antibodies. To characterize their reactivity profiles, human and bovine β2GPI were immobilized on γ-irradiated plates (β2GPI-ELISA), plain polystyrene precoated with increasing cardiolipin concentrations (CL/β2GPI-ELISA), and affinity columns. Fluid-phase inhibition experiments were also carried out with both proteins. Of 56 selected sera, restricted recognition of bovine or human β2GPI occurred respectively in 10/29 IgA-positive and 9/22 IgM-positive samples, and most of the latter (8/9) were missed by the standard ACA assay, as expected from a previous study. Based on species specificity and ACA results, IgG-positive samples (53/56) were categorized into three groups: antibodies reactive to bovine β2GPI only (group I) or to bovine and human β2GPI, group II being ACA-negative, and group III being ACA-positive. The most important group, group III (n = 33) was characterized by (i) binding when β2GPI was immobilized on γ-irradiated polystyrene or cardiolipin at sufficient concentration (regardless of β2GPI density, as assessed using 125I-β2GPI); (ii) and low avidity binding to fluid-phase β2GPI (Kd in the range 10–5 M). In contrast, all six group II samples showed (i) ability to bind human and bovine β2GPI immobilized on non-irradiated plates; (ii) concentration-dependent blockade of binding by cardiolipin, suggesting epitope location in the vicinity of the phospholipid binding site on native β2GPI; (iii) and relative avidities approximately 100-fold higher than in group III. Group I patients were heterogeneous with respect to CL/β2GPI-ELISA and ACA results (6/14 scored negative), possibly reflecting antibody differences in terms of avidity and epitope specificity. Affinity fractionation of 23 sera showed the existence, in individual patients, of various combinations of antibody subsets solely reactive to human or bovine β2GPI, together with cross-species reactive subsets present in all samples with dual reactivity namely groups III and II, although the latter antibodies were poorly purified on either column. Therefore, the mode of presentation of β2GPI greatly influences its recognition by anti-β2GPI antibodies with marked inter-individual heterogeneity, in relation to ACA quantitation and, possibly, disease presentation and pathogenesis.


Phlebologie ◽  
2003 ◽  
Vol 32 (05) ◽  
pp. 115-120 ◽  
Author(s):  
A. Franek ◽  
H. Koziolek ◽  
M. Kucharzewski

SummaryAim: The study of the influence of sulodexide in the treatment of venous leg ulcers. Patients and method: 44 patients with chronic venous ulceration were randomly divided into two groups. Group I: 21 patients (ulceration area: 12.7-18.9 cm2), Group II: 23 patients (ulceration size: 12.1-20.3 cm2). Both groups were treated by using Unna’s boot. This dressing was changed every seven days until the ulcer had healed. Additionally, the patients in group II received the systemic pharmacological treatment with sulodexide. Results: After 7 weeks of treatment ulcers of seven patients (35%) from group I had healed, and 3 weeks later the ulceration of two more patients had healed completely. After further 7 weeks the ulcers of 12 patients had healed completely. Whereas in group II after 7 weeks of treatment ulceration of 16 (70%, p <0.05) patient had healed completely and after further 3 weeks the ulcers of the remaining 7 patients had healed, too. Conclusion: The use of sulodexide in patients with chronic venous leg ulcers accelerates the healing process.


1997 ◽  
Vol 36 (08) ◽  
pp. 259-264
Author(s):  
N. Topuzović

Summary Aim: The purpose of this study was to investigate the changes in blood activity during rest, exercise and recovery, and to assess its influence on left ventricular (LV) volume determination using the count-based method requiring blood sampling. Methods: Forty-four patients underwent rest-stress radionuclide ventriculography; Tc-99m-human serum albumin was used in 13 patients (Group I), red blood cells was labeled using Tc-99m in 17 patients (Group II) in vivo, and in 14 patients (Group III) by modified in vivo/in vitro method. LV volumes were determined by a count-based method using corrected count rate in blood samples obtained during rest, peak exercise and after recovery. Results: In group I at stress, the blood activity decreased by 12.6 ± 5.4%, p <0.05, as compared to the rest level, and increased by 25.1 ± 6.4%, p <0.001, and 12.8 ± 4.5%, p <0.05, above the resting level in group II and III, respectively. This had profound effects on LV volume determinations if only one rest blood aliquot was used: during exercise, the LV volumes significantly decreased by 22.1 ± 9.6%, p <0.05, in group I, whereas in groups II and III it was significantly overestimated by 32.1 ± 10.3%, p <0.001, and 10.7 ± 6.4%, p <0.05, respectively. The changes in blood activity between stress and recovery were not significantly different for any of the groups. Conclusion: The use of only a single blood sample as volume aliquot at rest in rest-stress studies leads to erroneous estimation of cardiac volumes due to significant changes in blood radioactivity during exercise and recovery.


1994 ◽  
Vol 72 (05) ◽  
pp. 745-749 ◽  
Author(s):  
Elza Chignier ◽  
Maud Parise ◽  
Lilian McGregor ◽  
Caroline Delabre ◽  
Sylvie Faucompret ◽  
...  

SummaryP-selectin, also known as CD62P, GMP140 or PADGEM, is present in platelet a-granules and endothelial cell Weibel-Palade bodies and is very rapidly expressed on the surface of these cells on activation. In this study, an anti P-selectin monoclonal antibody (LYP20) was used, in tandem with flow cytometry, to identify activated platelets at the site of induced vascular trauma or in peripheral blood. Moreover, electron microscopy was performed to characterize sites of vascular trauma and quantify the number of adhering platelets. The same induced vascular trauma was observed to result into animals responding in 2 different ways (Group I, Group II) following the degree of platelet activation. Five rats, out of 14 with induced vascular trauma, had more than half of their circulating platelets expressing P-selectin when drawn at the site of the trauma (67.4% ± 3.44) or in peripheral blood (78.5% ± 2.5) (Group I). In the remaining 9 animals a much smaller proportion of circulating platelets expressed P-selectin when assayed from trauma sites (18% ± 3.34) or in peripheral blood (18.0% ± 4.30) (Group II). Enhanced P-selectin expression by circulating platelets in Group I, compared to Group II, appears to be linked to the degree of activated platelets adhering at sites of trauma (171 ± 15 × 103 platelets versus 48 ± 31 × 103 platelets per mm2). In the 5 control animals, that were not operated on, platelets expressing P-selectin when drawn at the site of a mock trauma (7.0% ± 1.84) or in the peripheral blood (11.2% ± 3.30) showed little activation. In addition, no platelet adhesion was seen on the vascular bed of these animals. Results from this study show that analysis of P-selectin (CD62P) expression, in circulating platelets, is a valuable and rapid marker of platelet activation following severe vascular trauma induced in rats. However, activated platelets were not detected to the same extent in the peripheral blood of all animals having undergone vascular trauma. It is conceivable that platelets, depending on the degree of activation, may be actively sequestered in organs and prevented from circulating. Alternatively, P-selectin may be rapidly endocytosed, or not expressed, by activated circulating platelets depending on the type of agonists implicated in vivo activation.


2012 ◽  
Vol 5 (1) ◽  
pp. 37-43
Author(s):  
ABMM Alam ◽  
M Moniruzzaman ◽  
MB Alam ◽  
N Islam ◽  
F Khatoon ◽  
...  

Background: CIN has gained increased attention in the clinical setting, particularly during cardiac intervention but also in many other radiological procedures in which iodinated contrast media are used. There is at present good clinical evidence from well-controlled randomized studies that CIN is a common cause of acute renal dysfunction.Methodology: This was a prospective study conducted among the patients who underwent coronary angiography and percutaneous coronary intervention in the Department of Cardiology, Dhaka Medical College Hospital during January 2010 to December 2010. A total of 111 patients age range from 25 to 75 years were included in the study. Serum creatinine level at baseline and at the end of 48 hours was done in all these patients. Study population was divided into two groups according to development of acute kidney injury (AKI). Group-I = AKI, Group II = Not developed AKI. Results: AKI developed 11.7% of the study patient. DM and Preexisting renal insufficiency were significantly higher in group I patients. HTN was (61.5% Vs 44.9%) higher in group I but not significantly. History of ACE inhibitor/ARB, NSAID intake and LVEF <40% were significantly higher in group I patients. The mean±SD volume of CM (Contrast Media) were 156.9±44.8 ml and 115.4±30.0 ml in group I and group II respectively, which was significant. The mean±SD of serum creatinine after 48-72 hours of CAG/PCI was 1.4±0.37 mg/dl and 1.1±0.2 mg/dl in group I and group II respectively. The serum creatinine level increased significantly (p<0.05) after 48-72 hours of CAG/PCI in group I. In group II, S. creatinine level increased but not significant (p>0.05). Impaired renal function was found 76.9% and 2.0% in group I and group II respectively. DM, HTN, preexisting renal insufficiency, ACE inhibitor/ARB, NSAIDs, contrast volume (>150 ml), eGFR (<60 ml/min/ 1.73m2) and LVEF (<40%) are significantly (p0.05) associated for CIN development.Conclusion: CIN is an iatrogenic but preventable disorder results from the administration of contract media. Although rare in the general population, CIN occurs frequently in patients with underlying renal dysfunction and diabetes. In patients with pre angiographic normal renal function, the prevalence is low but in pre-existing renal impairment it may pose a serious threat. Thus risk factors are synergistic in their ability to predispose to the development of CIN. A careful risk-benefit analysis must always be performed prior to the administration of contrast media to patients at risk for CIN. DOI: http://dx.doi.org/10.3329/cardio.v5i1.12227 Cardiovasc. j. 2012; 5(1): 37-43


1980 ◽  
Vol 94 (3) ◽  
pp. 315-320 ◽  
Author(s):  
D. Schams ◽  
E. Stephan ◽  
R. D. Hooley

Abstract. Six Holstein bulls were housed in a climate-chamber under constant light regimen and after two weeks of preconditioning at 15°C, 60% relative humidity RH (day) and 12°C, 60% RH (night) were subjected to two weeks of heat exposure. This involved one week at 30°C and 60% RH (day) and 25°C and 60% RH (night) and a further week at 35°C, 60% RH (day) and 30°C, 60% RH (night). Three bulls were untreated (group I) and 3 bulls were treated (group II) just before and during heat exposure with a prolactin inhibitor to study the possible physiological role of prolactin on the regulation of water, potassium and sodium. Serum prolactin levels increased significantly (P < 0.01) in group I from the control value of 6 ng/ml to 33 and 44 ng/ml when the ambient temperature was increased (weeks 3 and 4) and then decreased to 21 and 12 ng/ml after reduction in temperature during weeks 5 and 6, respectively. For group II prolactin values decreased under the treatment with the prolactin inhibitor to 0.5 ng/ml and remained at this level throughout the experiment. GH levels were unaffected by heat treatment or by treatment with prolactin inhibitor. There were no differences between groups I and II in respiratory rate, pulse rate and rectal temperature. Water intake increased in both groups under heat exposure but decreased significantly afterwards only in group II. Differences in urinary excretion volume and blood serum osmolality were not significant. Urinary potassium and sodium excretion were unchanged in group II but increased with heat exposure in group I. During heat exposure 2 bulls of group II lost weight despite maintaining food intake.


1986 ◽  
Vol 113 (4_Suppl) ◽  
pp. S157-S163 ◽  
Author(s):  
K.W. KASTRUP ◽  
_ _

Abstract Early therapy with a low dose of estrogen (estradiol-17β) was given to 33 girls with Turner's syndrome (T.s.) for a period of 4 years. The dose (0.25-2 mg/day) was adjusted every 3 months to maintain plasma estradiol in the normal concentration range for bone age. Growth velocity was compared with that of untreated girls with T.s. All girls were above age 10 years. Bone age was below 10 years in 11 girls (group I) and above 10 years in 22 girls (group II). Growth velocity in the first year of treatment in group I 7.5 ± 1.3 cm (SD) with mean SD score (SDS) of +4.3 and in group II 4.9 ± 1.3 with mean SDS of +3.5. Growth velocity decreased in the following years to 1.6 ± 1.0 cm, SDS -1.44 in group I and 0.9 ± 0.6cm, SDS -2.34 in group II during the fourth year. Withdrawal bleeding occurred in 16 girls of group II after the mean of 23 (range 15-33) months and in 3 girls of group I after 15 to 51 months of treatment. The treatment did not cause an inappropriate acceleration of pubertal development. Breast development appeared in most girls by 3 months of treatment. Pubic hair appeared by 12 months of treatment in group I; it was present in most girls in group II at start of treatment. Final height is known for 12 girls of group II; it was 144.2 ± 4.5 cm. The final height as predicted at the start of therapy was 142.2 ± 5.3 cm. Bone age advanced in the first year of treatment by 2 years. Early treatment with small doses of estrogens induces a growth spurt and normalizes the events of puberty. This will presumably decrease the psychological risks associated with abnormally delayed development.


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