scholarly journals Key Factors Contributing to The Anchorage Loss of Maxillary First Molars: A Retrospective Study of 726 Extraction Cases

Author(s):  
Hong Su ◽  
Kaiyuan Xu ◽  
Bing Han ◽  
Gui Chen ◽  
Tianmin Xu

Abstract Background: Anchorage control is one of the key components in the treatment of extraction cases. However, why anchorage loss happens is still an unanswered question. The purpose of this study was to investigate the most important factors contributing to the anchorage loss of maxillary first molars in premolar extraction cases. The study enrolled 726 upper premolar extraction cases, including 214 male patients and 512 female patients, and the average age was 14 (range: 9-45 years old).Factors including physiological characteristics, treatment mechanics and cephalometric variables were collected and their influences on the angulation changes of maxillary first molars were analyzed. Results: The average angulation change of maxillary first molar after treatment was 2.81°, meaning the molar tipped forward during treatment by 2.81°. The change of UM/PP showed statistically significant difference in different sex ( male 3.84°±5.26 ° vs female 2.38°±5.10°), age (adult -0.05°±4.73 ° vs teenager 3.46°±5.07°), and molar relationship(Class II 3.28°±5.15°vs Class I 2.36°±5.19°). There are six variables accounted in the regression analysis (R=0.608, R²=37.0%). Among them, the pre-treatment molar tipping (Standardized Coefficients:-0.65) and the pre-treatment incisor/molar height ratio (Standardized Coefficients:-0.27)were the most important factors influencing anchorage loss during treatment.Conclusion: Compared with treatment-related factors, the patient’s physiological characteristics play a more important role in anchorage loss. The pre-treatment angulation of the maxillary first molar is the most contributing factor of the maxillary molar angulation changes, which are often predisposing anchorage loss.

2021 ◽  
Author(s):  
Hong Su ◽  
Kaiyuan Xu ◽  
Bing Han ◽  
Gui Chen ◽  
Tianmin Xu

Abstract Background: Anchorage control is one of the key components in the treatment of extraction cases. However, why anchorage loss happens is still an unanswered question. The purpose of this study was to investigate the most important factors contributing to the anchorage loss of maxillary first molars in premolar extraction cases. Methods:The study enrolled 726 upper premolar extraction cases, including 214 male patients and 512 female patients, and the average age was 14 (range: 9-45 years old).Factors including physiological characteristics, treatment mechanics and cephalometric variables were collected and their influences on the angulation changes of maxillary first molars were analyzed. Results: The average angulation change of maxillary first molar after treatment was 2.81°, meaning the molar tipped forward during treatment by 2.81°. The change of UM/PP showed statistically significant difference in different sex ( male 3.84°±5.26 ° vs female 2.38°±5.10°), age (adult -0.05°±4.73 ° vs teenager 3.46°±5.07°), and molar relationship(Class II 3.28°±5.15°vs Class I 2.36°±5.19°). There are six variables accounted in the regression analysis (R=0.608, R²=37.0%). Among them, the pre-treatment molar tipping (Standardized Coefficients:-0.65) and the pre-treatment incisor/molar height ratio (Standardized Coefficients:-0.27)were the most important factors influencing anchorage loss during treatment.Conclusion: Compared with treatment-related factors, the patient’s physiological characteristics play a more important role in anchorage loss. The pre-treatment angulation of the maxillary first molar is the most contributing factor of the maxillary molar angulation changes, which are often predisposing anchorage loss.


2019 ◽  
Vol 89 (4) ◽  
pp. 605-610
Author(s):  
Yassir A. Yassir ◽  
Grant T. McIntyre ◽  
Ahmed M. El-Angbawi ◽  
David R. Bearn

ABSTRACT Objectives: To compare maxillary first molar anchorage loss between 0.018-inch and 0.022-inch slot fixed appliance systems. Materials and Methods: Patients requiring bilateral maxillary premolar extractions (n = 74) within a randomized clinical trial comparing the effectiveness of 0.018-inch and 0.022-inch slot MBT bracket systems (3M-Unitek, Monrovia, Calif) were included. Three-dimensional pre- and posttreatment digital models were landmarked and measured (R700 scanner and OrthoAnalyzer software, 3Shape, Copenhagen, Denmark). Anteroposterior position of the first molars was measured using the third medial rugae point as a reference. Anchorage loss (AL) represented the subtraction of the posttreatment distance from the pretreatment distance for both anchorage loss right (ALR) and left (ALL) sides. The values were then compared using a two-way analysis of variance. Results: There were 41 and 33 cases for the 0.018-inch and 0.022-inch bracket slot systems, respectively. The baseline characteristics were similar between groups, except for the presence or absence of anchorage devices (P = .050). For the total sample: 0.018-inch ALR = 3.86 mm, ALL = 3.30 mm and 0.022-inch ALR = 3.73 mm, ALL = 3.47 mm (P = .970). There was also no significant difference between the 0.018-inch and 0.022-inch groups when subjects with anchorage devices were excluded (P = .383). Conclusions: Bracket slot size does not influence maxillary molar anchorage loss during orthodontic treatment.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Federico Raimondi ◽  
◽  
Luca Novelli ◽  
Arianna Ghirardi ◽  
Filippo Maria Russo ◽  
...  

Abstract Background Gender-related factors might affect vulnerability to Covid-19. The aim of this study was to describe the role of gender on clinical features and 28-day mortality in Covid-19 patients. Methods Observational study of Covid-19 patients hospitalized in Bergamo, Italy, during the first three weeks of the outbreak. Medical records, clinical, radiological and laboratory findings upon admission and treatment have been collected. Primary outcome was 28-day mortality since hospitalization. Results 431 consecutive adult patients were admitted. Female patients were 119 (27.6%) with a mean age of 67.0 ± 14.5 years (vs 67.8 ± 12.5 for males, p = 0.54). Previous history of myocardial infarction, vasculopathy and former smoking habits were more common for males. At the time of admission PaO2/FiO2 was similar between men and women (228 [IQR, 134–273] vs 238 mmHg [150–281], p = 0.28). Continuous Positive Airway Pressure (CPAP) assistance was needed in the first 24 h more frequently in male patients (25.7% vs 13.0%; p = 0.006). Overall 28-day mortality was 26.1% in women and 38.1% in men (p = 0.018). Gender did not result an independent predictor of death once the parameters related to disease severity at presentation were included in the multivariable analysis (p = 0.898). Accordingly, the Kaplan–Meier survival analysis in female and male patients requiring CPAP or non-invasive ventilation in the first 24 h did not find a significant difference (p = 0.687). Conclusion Hospitalized women are less likely to die from Covid-19; however, once severe disease occurs, the risk of dying is similar to men. Further studies are needed to better investigate the role of gender in clinical course and outcome of Covid-19.


2020 ◽  
Vol 12 (4) ◽  
pp. 185
Author(s):  
Shueh-Chin Ting

In the past, there has been a dearth of research exploring related factors regarding the benefactor in the research of gratitude. The focus of this study is to investigate whether different benefactors elicit different levels of gratitude in beneficiaries after conferring a favor. Using college students as the research subjects, questionnaires were conducted after subjects read the experimental text to explore whether college students’ gratitude is different when two types of benefactors (friends and parents) give the same help. This study found that when the benefactor makes a big effort to confer a favor and the favor is very important to the beneficiary, there is no significant difference in the gratitude toward their parents and friends among college students and the level of gratitude for both is very high. However, when the favor only is conferred through an ordinary amount of effort and the favor is of ordinary importance to the beneficiary, college students have a higher level of gratitude to their friends, but a lower level of gratitude to their parents. Therefore, college students do not necessarily have higher gratitude to their friends than to their parents; the amount of effort exerted by the benefactor and the importance of the favor to the beneficiary are two key factors.


Author(s):  
P Han ◽  
A Turpie ◽  
E Genton ◽  
M Gent

Platelets play a role in the development and complications of coronary artery disease (CAD) and a number of abnormalities of platelet function which can be corrected by antiplatelet drugs have been described. Betathromboglobulin (BTG), a platelet-specific protein which is released from α-granules during platelet activation is significantly elevated in patients with angiographically demonstrated CAD (51.0 ± 31.0 ng/ml., n = 50) compared to normal (28.0 ± 8.0 ng/ml., n = 70) p < 0.001. The effect of sulphinpyrazone (800 mg.) or aspirin (1200 mg.)/dipyridamole (200 mg.) on plasma BTG in CAD was studied in a blind prospective crossover trial in 25 patients. Mean BTG concentration pre-treatment was 52.3 ng/ml. and after 1 month’s treatment with placebo, sulphinpyrazone or aspirin/dipyridamole mean plasma BTG concentrations were 53.5, 49.6 and 56.7 ng/ml. respectively. Analysis of variance showed no significant difference between the means (p > 0.1) . This study confirms increased plasma BTG concentrations in patients with CAD and indicates that therapeutic doses of these antiplatelet drugs do not significantly effect the BTG level and thus appear not to prevent α-granule release in CAD.


1960 ◽  
Vol XXXV (III) ◽  
pp. 381-396 ◽  
Author(s):  
Sven Almqvist

ABSTRACT The sulfation factor (SF) activity of human sera has been estimated using a modification of the method of Daughaday et al. (1959). Each assay was statistically evaluated. The method had a mean precision of 0.14 and, used as an assay of GH of human serum, a sensitivity in three pituitary dwarfs of 0.1 to 0.6 μg of HGH/ml of serum. SF activity was found at all ages between 1 month and 75 years. There was a significantly lower mean SF activity below the age of half a year. Three cases of pituitary dwarfism had significantly low SF activities of sera. There was no significant difference between the SF activities of sera from untreated pituitary dwarfs and the sera from normal children below half a year of age. Dose-response curves with large volumes of sera from pituitary dwarfs and small volumes of sera from normal humans had the same slopes. Four mg of HGH prepared according to the method of Li & Papkoff (1956) resulted in a normal serum SF activity in each of the three dwarfs. A significant (P < 0.01) linear relationship was found between the concentration of SF activity of sera from these subjects and the logarithm of the dose of HGH given with dose levels of 1, 2 and 4 mg daily for three days. The decline of serum SF activity to the pre-treatment level following HGH in one dwarf suggested a half life not different from that indicated by others for growth hormone.


2019 ◽  
Vol 118 (5) ◽  
pp. 122-131
Author(s):  
S. Thowseaf ◽  
M. Ayisha Millath ◽  
K. Malik Ali

Tax is an important source of income for the country. It is through tax; country strengthens its defense system, infrastructure, and government. Hence, tax system plays a predominant role in developing country’s economy. The complication in taxation system and liberty for taxpayers are key factors generating loopholes for corruption. GST is superior taxation system over VAT but, if neither properly implemented nor scrutinized according to the economy, it is people residing get affected.  GST taxation system is capable of increasing legal transaction, reducing corruption and complexity that exists in current taxation. India is 166th country to adopt GST and GST taxation slab in India is 0%, 5%, 12%, 18% and 28%.  Although average Tax levied is 14.8750% in India, it is 28% tax that is levied for most of the commodities, which are directly or indirectly used in everyday life of common individuals. Despite, GST being favorable to distributor in-terms of profit and government to attain tax by increasing legal transaction through invoice. It is noted that for the same percentage of taxation, the amount does not vary for VAT and GST. The tax slab decreased for 71 commodities and no change in 21 commodities; there has been an increase in tax slab for 60 commodities. 26% taxation was levied for most commodities considered was currently levied by 28% taxation which is greater than before. It was found that average tax percentage reduced was calculated to be 6.07143. The average tax percentage increase was calculated to be 4.7833 percentage for the considered commodities. The overall tax average tax percentage is estimated to be 14.8750% which does not have a significant difference concerning tax levied before GST, which was calculated to be 15.7829% for considered commodities. Therefore, the consumer purchasing power and overall living standard of the individual in India will remain almost same.


2017 ◽  
Vol 17 (1) ◽  
pp. 93-98
Author(s):  
Zheng Yue ◽  
Zhang Wen-Cheng ◽  
Wu Ze-Yu ◽  
Fu Chuan-Xiang ◽  
Gao Han ◽  
...  

The purpose of this study was to evaluate the anti-fatigue activity of maca hydroalcoholic extract (ME), which mainly contains macamides and polysaccharides. ME was prepared by circumfluence extraction with enzymatic pre-treatment. Anti-fatigue activity of ME was investigated in weight-loaded forced swimming mice, with pure macamides and commercially available maca tablet as positive control. Compared with normal group, pure macamides treatment group could prolong the swimming time to exhaustion, but there was no statistically significant difference (P > 0.05); while ME (middle-dose and high-dose groups) could effectively prolong the swimming durations (P < 0.05). Supplementation with pure macamides significantly decreased blood lactic acid (BLA), whereas ME significantly increased hepatic glycogen (HG), decreased BLA, and blood urea nitrogen (BUN) compared with those in normal control (P < 0.05). The results suggested that the anti-fatigue effect of ME was better than that of pure macamides, which can be explained by the increase of glycogen storage and the reduction of metabolites accumulation.


Author(s):  
Gero Stefan Michael Kinzinger ◽  
Jan Hourfar ◽  
Jörg Alexander Lisson

Abstract Purpose Conventional anchorage with exclusively intraorally anchored appliances for non-compliance molar distalization combines a palatal acrylic button with periodontal anchorage. This type of anchorage is critically discussed because of the temporary hygienic impairment of the palate and the uncertain anchoring quality of the button. A purely dentally/periodontally anchored Pendulum K appliance was developed, which is exclusively anchored via four occlusal rests. The aims of this pilot study were to examine the suitability of the skeletonized Pendulum K for distalization of maxillary molars, and to investigate the quality of this alternative anchoring modality. Patients and methods In all, 10 patients received skeletonized Pendulum K appliances attached to all maxillary premolars for bilateral molar distalization. Supporting anchorage through an acrylic button adjacent to the anterior palate was not used. The pendulum springs were initially activated on both sides with a distalization force of 220 cN each and provided with uprighting and toe-in bends. The specific force/moment system was regularly reactivated intraorally by adjustment of the distal screw. Results The study demonstrates the suitability of the skeletonized Pendulum K appliance for the distalization of maxillary molars (3.28 ± 0.73 mm). Side effects on the molars were slight distal tipping (3.50 ± 2.51°/PP, 3.00 ± 1.41°/SN) and mesial inward rotation (average 2.75 ± 7.50° and 4.50 ± 12.77°). Significant anchorage loss occurred in the form of mesialization of the incisors by 1.40 ± 0.82 mm and of the first premolars by 2.28 ± 0.85 mm. Conclusion The skeletonized Pendulum K appliance allows compliance-free upper molar distalization. Exclusively dental/periodontal anchorage resulted in a lower percentage of molar distalization compared to a conventional anchoring preparation of the Pendulum K with a palatal acrylic button. Anchorage loss had a comparatively stronger effect on the anchoring premolars but less on the incisors. Typical side effects on the molars such as distal tipping and mesial inward rotation were remarkably low.


Author(s):  
Minjung Lee ◽  
Myoungsoon You

Avoidance of healthcare utilization among the general population during pandemic outbreaks has been observed and it can lead to a negative impact on population health. The object of this study is to examine the influence of socio-demographic and health-related factors on the avoidance of healthcare utilization during the global outbreak of a novel coronavirus (COVID-19) in 2020. Data were collected through an online survey four weeks after the Korea Centers for Disease Control and Prevention (KCDC) confirmed the first case in South Korea; 1000 subjects were included in the analysis. The logit model for regression was used to analyze the associations between sociodemographic and health-related factors regarding the avoidance of healthcare utilization. Among the participants, 73.2% avoided healthcare utilization, and there was no significant difference in the prevalence of healthcare avoidance between groups with (72.0%) and without (74.9%) an underlying disease. Sociodemographic characteristics (e.g., gender, age, income level, and residential area) were related to healthcare avoidance. Among the investigated influencing factors, residential areas highly affected by COVID-19 (i.e., Daegu/Gyeoungbuk region) had the most significant effect on healthcare avoidance. This study found a high prevalence of healthcare avoidance among the general population who under-utilized healthcare resources during the COVID-19 outbreak. However, the results reveal that not all societal groups share the burden of healthcare avoidance equally, with it disproportionately affecting those with certain sociodemographic characteristics. This study can inform healthcare under-utilization patterns during emerging infectious disease outbreaks and provide information to public health emergency management for implementing strategies necessary to improve the preparedness of the healthcare system.


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