scholarly journals Evaluation of long-term stability of mesiodistal axial inclinations of maxillary molars through panoramic radiographs in subjects treated with Pendulum appliance

2016 ◽  
Vol 21 (1) ◽  
pp. 67-74 ◽  
Author(s):  
Caroline Andrade Rocha ◽  
Renato Rodrigues de Almeida ◽  
José Fernando Castanha Henriques ◽  
Carlos Flores-Mir ◽  
Marcio Rodrigues de Almeida
Keyword(s):  
Panoramic Radiograph ◽  
Post Treatment ◽  
Control Group ◽  
Long Term Stability ◽  
Maxillary Molars ◽  
Group Data ◽  
Maxillary Molar ◽  
Pendulum Appliance ◽  
The Stability

Objective: To evaluate the stability of mesiodistal inclination of maxillary molars produced by a pendulum appliance, five years after completion of orthodontic treatment. Angulation changes were compared to an untreated sample. Methods: The sample consisted of 20 patients (14 females and 6 males) with Class II, Division 1 malocclusion that was treated through molar distalization with a pendulum appliance followed by cervical headgear and full fixed appliances. Maxillary molar inclination was evaluated through panoramic radiograph. The mean age at pretreatment was 14.3 ± 1.6 years, whereas at immediate post-treatment it was 18.6 ± 1.8 years, and at long-term post-treatment it was 23.8 ± 2.0 years. A control group of 16 untreated individuals with untreated normocclusion ranging in age from 12 to 17 years old were used as comparison group. Data were statistically analyzed with independent t-tests and ANOVA test followed by Tukey post-hoc tests. Results: Statistically significant differences were found between T1 (94.50) and T2 (98.80) as well as between T2 and T3 (94.70) for maxillary first molars. Maxillary second molars did not show any statistically significant positional changes during the evaluated time periods T1 (107.50), T2 (109.30) and T3 (106.90). Conclusion: Although maxillary first molars underwent distal crown inclination immediately after treatment, approximately five years thereafter their roots tended to upright close to the pretreatment positions.

scholarly journals Long-term stability of miniscrew anchored maxillary molar distalization in Class II treatment

2020 ◽  
Vol 90 (3) ◽  
pp. 362-368 ◽  
Author(s):  
Till Edward Bechtold ◽  
Young-Chel Park ◽  
Kyung-Ho Kim ◽  
Heekyu Jung ◽  
Ju-Young Kang ◽  
...  
Keyword(s):  
Class Ii ◽  
Vertical Movement ◽  
Occlusal Plane ◽  
Control Group ◽  
Long Term Stability ◽  
Class Ii Treatment ◽  
Lateral Cephalograms ◽  
Maxillary Molar ◽  
Group A

ABSTRACT Objective To investigate treatment stability of miniscrew-anchored maxillary distalization in Class II malocclusion. Materials and Methods This retrospective study included a distalization (n = 19) and a control (n = 19) group; a patient group with minor corrections served the control. Lateral cephalograms of 38 adult patients were taken before (T0), immediately after (T1), and 3–4 years after (T2) treatment. Horizontal and vertical movement and tipping of the maxillary first molars (U6) and central incisors (U1) were measured along with skeletal craniofacial parameters at three time points to compare the two groups regarding the achieved treatment effects and their stability. Results Total arch distalization therapy led to 4.2 mm of distal movement of U6 without distal crown tipping (0.6° of axis change) and 3.3° of occlusal plane steepening. Over an average retention period of 42 months, maxillary total arch distalization provided high stability of treatment results, showing the same amount of mesial movement (0.7 mm) as the control group. Conclusions In Class II treatment, miniscrew-anchored maxillary total arch distalization can provide stable distal movement of the maxillary first molars and central incisors.

Stability of Implicit Self-Esteem Among Internetaddicted College Students in China

2017 ◽  
Vol 45 (2) ◽  
pp. 339-352 ◽  
Author(s):  
Lingbo Zhao ◽  
Xianglian Yu ◽  
Lixian Zhang ◽  
Zhihong Ren
Keyword(s):  
College Students ◽  
Internet Addiction ◽  
Positive Feedback ◽  
Self Esteem ◽  
Group Differences ◽  
The Internet ◽  
Control Group ◽  
Long Term Stability ◽  
The Stability

We explored the stability of, and between-group differences in, the implicit self-esteem of Internet-addicted and Internet-nonaddicted college students in China. Internet addiction was assessed using Young's Internet Addiction Scale and the participants comprised 52 Internet addicts (26 men, 26 women) and 52 Internet nonaddicts (26 men, 26 women). We then used the Implicit Association Test to assess levels of implicit self-esteem, employing a 2 (addiction, nonaddiction) × 2 (positive feedback, negative feedback) between-subjects factorial design. The pretest implicit self-esteem level of the Internet-addicted group was significantly higher than that of the control group; however, the implicit self-esteem levels of both groups were unstable. Positive feedback did not change the level of implicit self-esteem of the Internet addiction group. In future studies researchers need to pay more attention to the measurement of implicit self-esteem, long-term stability, and addiction to online games.

The Stability of the WHO Reference Thromboplastin NIBS & C 67/40

1979 ◽  
Vol 42 (04) ◽  
pp. 1135-1140 ◽  
Author(s):  
G I C Ingram
Keyword(s):  
Human Brain ◽  
Collaborative Study ◽  
Calibration Constant ◽  
Long Term Stability ◽  
Freeze Dried ◽  
Show Evidence ◽  
Human Material ◽  
Reference Preparation ◽  
The Stability

SummaryThe International Reference Preparation of human brain thromboplastin coded 67/40 has been thought to show evidence of instability. The evidence is discussed and is not thought to be strong; but it is suggested that it would be wise to replace 67/40 with a new preparation of human brain, both for this reason and because 67/40 is in a form (like Thrombotest) in which few workers seem to use human brain. A �plain� preparation would be more appropriate; and a freeze-dried sample of BCT is recommended as the successor preparation. The opportunity should be taken also to replace the corresponding ox and rabbit preparations. In the collaborative study which would be required it would then be desirable to test in parallel the three old and the three new preparations. The relative sensitivities of the old preparations could be compared with those found in earlier studies to obtain further evidence on the stability of 67/40; if stability were confirmed, the new preparations should be calibrated against it, but if not, the new human material should receive a calibration constant of 1.0 and the new ox and rabbit materials calibrated against that.The types of evidence available for monitoring the long-term stability of a thromboplastin are discussed.

scholarly journals Limitations and Challenges in the Stability of Cysteamine Eye Drop Compounded Formulations

2021 ◽  
Vol 15 (1) ◽  
pp. 2
Author(s):  
Cristina Martín-Sabroso ◽  
Mario Alonso-González ◽  
Ana Fernández-Carballido ◽  
Juan Aparicio-Blanco ◽  
Damián Córdoba-Díaz ◽  
...  
Keyword(s):  
Shelf Life ◽  
Stability Study ◽  
Eye Drops ◽  
Microbiological Analysis ◽  
Nitrogen Gas ◽  
Long Term Stability ◽  
Main Degradation Product ◽  
The Stability ◽  
Unstable Molecule

Accumulation of cystine crystals in the cornea of patients suffering from cystinosis is considered pathognomonic and can lead to severe ocular complications. Cysteamine eye drop compounded formulations, commonly prepared by hospital pharmacy services, are meant to diminish the build-up of corneal cystine crystals. The objective of this work was to analyze whether the shelf life proposed for six formulations prepared following different protocols used in hospital pharmacies is adequate to guarantee the quality and efficacy of cysteamine eye drops. The long-term and in-use stabilities of these preparations were studied using different parameters: content of cysteamine and its main degradation product cystamine; appearance, color and odor; pH and viscosity; and microbiological analysis. The results obtained show that degradation of cysteamine was between 20% and 50% after one month of storage in the long-term stability study and between 35% and 60% in the in-use study. These data confirm that cysteamine is a very unstable molecule in aqueous solution, the presence of oxygen being the main degradation factor. Saturation with nitrogen gas of the solutions offers a means of reducing cysteamine degradation. Overall, all the formulae studied presented high instability at the end of their shelf life, suggesting that their clinical efficacy might be dramatically compromised.

scholarly journals EFFECT OF COMBINATION OF HYPNOBREASTFEEDING AND ACUPRESSURE ON ANXIETY AND WOUND PAIN IN POST-CAESAREAN MOTHERS

2017 ◽  
Vol 3 (5) ◽  
pp. 525-532
Author(s):  
Diah Evawanna Anuhgera ◽  
Tjahjono Kuncoro ◽  
Sri Sumarni ◽  
Mardiyono Mardiyono ◽  
Ari Suwondo
Keyword(s):  
Public Hospital ◽  
Alternative Therapy ◽  
Control Group ◽  
P Value ◽  
Control Group Design ◽  
Group Data ◽  
Before And After ◽  
Wound Pain ◽  
And Control

Background: Post-cesarean mothers often experience anxiety and discomfort due to long-term pain. The combination of hypnobreastfeeding and acupressure is considered to be effective in reducing anxiety and pain levels. Objective: This study aims to examine the effect of combination of hypnobreastfeeding and acupressure on anxiety and pain levels in post-caesarean mothers.Methods: This study was a true experiment with pretest-posttest control group design, conducted in the Ambarawa Public Hospital on 5 November to 9 December 2016. There were 36 participants selected using stratified random sampling, with 18 assigned in the experiment and control group. Data were analyzed using paired t-test and wilcoxon test.Results: There were statistically significant differences of anxiety and pain levels before and after intervention in the experiment and control group with p-value 0.001 (<0.05).Conclusion: The combination of hypnobreastfeeding and acupressure has a significant effect in reducing anxiety and pain levels in post-cesarean mothers. This intervention could be applied as an alternative therapy in treating post-caesarean mothers.

scholarly journals Stress Distribution in Modified Veneer Crowns: 3D Finite Element Analysis

Oral ◽  
2021 ◽  
Vol 1 (3) ◽  
pp. 272-280
Author(s):  
Camila Ferreira Leite Madruga ◽  
Gabriela Freitas Ramos ◽  
Alexandre Luiz Souto Borges ◽  
Guilherme de Siqueira Ferreira Anzaloni Saavedra ◽  
Rodrigo Othávio Souza ◽  
...  
Keyword(s):  
Stress Concentration ◽  
Maximum Principal Stress ◽  
Zirconia Ceramic ◽  
Control Group ◽  
Element Analysis ◽  
New Approach ◽  
Biomechanical Behavior ◽  
Maxillary Molars ◽  
Maxillary Molar ◽  
Group B

(1) Background: to propose a new approach for crown veneers, with the use of an aesthetic porcelain coating, only in part of the zirconia infrastructure, and to analyze its biomechanical behavior to minimize chipping failures. (2) Methods: a maxillary molar was modeled using CAD software, preparing for traditional crowns and veneer crowns with various lengths. Five groups were formed: M—control group (monolithic crown of ultra-translucent zirconia); B—conventional (bilayer crown of ultra-translucent zirconia and ceramic covering); V—veneer (ultra-translucent zirconia crown with reduction only in the buccal and application of covering ceramics); V1—ultra-translucent zirconia crown with buccal reduction and 1 mm occlusal extension for covering ceramic application); V1.5—ultra-translucent zirconia crown with buccal reduction and 1.5 mm occlusal extension for application of covering ceramics. A load of 600 N was performed axially to a fossa bottom to simulate parafunction, and 300 N to the cusp tip to obtain the maximum principal stress results. (3) Results: group B showed a higher stress concentration in the occlusal region of the restorations, while the other groups absorbed the stress and dissipated it throughout the crown, presenting a higher stress concentration in the interface region with the tooth. (4) Conclusion: the highly translucent zirconia ceramic only associated with buccal covering ceramic could add aesthetic gain and rigidity to the system and could be a good option to restore maxillary molars in patients who do not have parafunction.

LONG-TERM STABILITY ANALYSIS OF ACOUSTIC ABSORBING BOUNDARY CONDITIONS

2013 ◽  
Vol 23 (11) ◽  
pp. 2129-2154 ◽  
Author(s):  
HÉLÈNE BARUCQ ◽  
JULIEN DIAZ ◽  
VÉRONIQUE DUPRAT
Keyword(s):  
Stability Analysis ◽  
Boundary Conditions ◽  
Absorbing Boundary Conditions ◽  
Computational Domain ◽  
Acoustic Wave Equation ◽  
Absorbing Boundary ◽  
Term Stability ◽  
Long Term Stability ◽  
The Stability

This work deals with the stability analysis of a one-parameter family of Absorbing Boundary Conditions (ABC) that have been derived for the acoustic wave equation. We tackle the problem of long-term stability of the wave field both at the continuous and the numerical levels. We first define a function of energy and show that it is decreasing in time. Its discrete form is also decreasing under a Courant–Friedrichs–Lewy (CFL) condition that does not depend on the ABC. Moreover, the decay rate of the continuous energy can be determined: it is exponential if the computational domain is star-shaped and this property can be illustrated numerically.

A Review of Preparation and Tribological Applications of Pickering Emulsion

2021 ◽  
pp. 1-27
Author(s):  
Yichen Bao ◽  
Kai Liu ◽  
Quan Zheng ◽  
Lulu Yao ◽  
Yufu Xu
Keyword(s):  
Pickering Emulsion ◽  
Solid Particles ◽  
Preparation Methods ◽  
Factors Affecting ◽  
Long Term Stability ◽  
New Strategy ◽  
New Type ◽  
The Stability ◽  
Near Future

Abstract Pickering emulsion is a new type of stable emulsion made by ultra-fine solid particles instead of traditional surfactants as stabilizers, which has received widespread attention in recent years. The preparation methods of stator-rotor homogenization, high-pressure homogenization, and ultrasonic emulsification were compared with others in this work. The main factors affecting the stability of Pickering emulsion are the surface humidity of the solid particles, the polarity of the oil phase, and the oil-water ratio. These factors could affect the nature of the solid particles, the preparation process of Pickering emulsion and the external environment. Consequently, the long-term stability of Pickering emulsion is still a challenge. The tribological investigations of Pickering emulsion were summarized, and the multifunctional Pickering emulsion shows superior prospects for tribological applications. Moreover, the latest development of Pickering emulsion offers a new strategy for smart lubrication in the near future.

Stability of a Piezoresistive Ceramic Pressure Sensor Made With LTCC Technology

2012 ◽  
Vol 2012 (CICMT) ◽  
pp. 000371-000376 ◽  
Author(s):  
Marina Santo Zarnik ◽  
Darko Belavic
Keyword(s):  
Pressure Sensor ◽  
Fatigue Testing ◽  
Low Pressure ◽  
Fatigue Tests ◽  
Point Of View ◽  
Long Term Stability ◽  
Pressure Cycling ◽  
Key Characteristics ◽  
The Stability

This paper discusses the stability of a piezoresistive, LTCC-based, pressure sensor that was designed for measurements in a low-pressure range below 100 mbar. The intrinsic stability of the sensor's offset was evaluated at a constant ambient temperature and different conditions regarding the atmospheric humidity. The sensors were also subjected to functional fatigue tests, which included a full-scale and an overload pressure cycling. The results of the fatigue testing revealed the vulnerability of the sensor's structure from the point of view of the long-term stability and the life-cycle. Nevertheless, the stability of the key characteristics of the prototype sensors was found to be satisfactory for accurate measurements in the low-pressure ranges.

Class II treatment in early mixed dentition with the eruption guidance appliance: effects and long-term stability

2019 ◽  
Vol 42 (2) ◽  
pp. 151-156 ◽  
Author(s):  
Katri Keski-Nisula ◽  
Leo Keski-Nisula ◽  
Juha Varrela
Keyword(s):  
Treatment Group ◽  
Class Ii ◽  
Post Treatment ◽  
Mixed Dentition ◽  
Term Stability ◽  
Long Term Stability ◽  
Class Ii Treatment ◽  
Significant Correction ◽  
The Mean

Summary Objectives Our aim was to analyse dentoskeletal effects and long-term stability of Class II treatment carried out with an eruption guidance appliance (EGA) in early mixed dentition. Materials and methods Sixty-five Class II patients (38 females and 27 males), treated with an EGA in early mixed dentition, were compared with 58 children (26 females and 32 males) with untreated Class II malocclusion. The mean age in the treatment group at the start (T1) and end of treatment (T2) was 5.4 years (±0.4) and 8.5 years (±0.9), respectively, and at the final examination in the early permanent dentition (T3) 16.7 years (±0.4). In the control group, the mean age at T1 and T2 were 5.1 years (±0.5) and 8.4 years (±0.5), respectively. The independent and dependent sample t-tests, Chi-square test, and Fisher’s test were used in the statistical evaluation. Results In the treatment group, the frequency of Class II decreased from 100 to 14% during the treatment (T1–T2) and a significant correction took place in all occlusal variables. At T2, the treatment and control groups showed statistically significant differences (P &lt; 0.05) in all occlusal variables. In the treated children, mandibular length increased 5 mm more (P &lt; 0.001) from T1 to T2 compared to the control children, and the ANB angle became significantly smaller (P = 0.006). During the post-treatment period (T2–T3), the frequency of Class II in the treatment group decreased from 14 to 2% (P &lt; 0.05), overbite increased from 2.2 to 3.1 mm (P &lt; 0.05), and lower crowding increased from 2to 14% (P &lt; 0.05). Post-treatment changes in overjet and upper crowding were not statistically significant. At T3, the mean values of the SNA, SNB, and ANB angles were 83.0° (SD 3.9°), 81.3° (SD 3.8°), and 2.4° (SD 1.5°), respectively. Conclusions A clinically significant correction of the molar relationship, overjet, overbite, incisor alignment, and growth enhancement of the mandible were observed after treatment in early mixed dentition. The treatment results remained largely stable in the early permanent dentition. However, an increase was observed in overbite and lower crowding. None of the children treated in early mixed dentition needed a second treatment phase.

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