scholarly journals LED vs Halogen Light-Curing of Adhesive-Precoated Brackets

2008 ◽  
Vol 78 (5) ◽  
pp. 935-940 ◽  
Author(s):  
Davide Mirabella ◽  
Raffaele Spena ◽  
Giovanni Scognamiglio ◽  
Lombardo Luca ◽  
Antonio Gracco ◽  
...  
Keyword(s):  
Failure Rate ◽  
Rank Test ◽  
Fisher Exact Test ◽  
Halogen Lamp ◽  
Chi Square ◽  
Halogen Light ◽  
Significant Difference ◽  
Chi Square Test ◽  
Light Curing ◽  
Bracket Failure

Abstract Objective: To test the hypothesis that bonding with a blue light-emitting diode (LED) curing unit produces no more failures in adhesive-precoated (APC) orthodontic brackets than bonding carried out by a conventional halogen lamp. Materials and Methods: Sixty-five patients were selected for this randomized clinical trial, in which a total of 1152 stainless steel APC brackets were employed. In order to carry out a valid comparison of the bracket failure rate following use of each type of curing unit, each patient's mouth was divided into four quadrants. In 34 of the randomly selected patients, designated group A, the APC brackets of the right maxillary and left mandibular quadrants were bonded using a halogen light, while the remaining quadrants were treated with an LED curing unit. In the other 31 patients, designated group B, halogen light was used to cure the left maxillary and right mandibular quadrants, whereas the APC brackets in the remaining quadrants were bonded using an LED dental curing light. The bonding date, the type of light used for curing, and the date of any bracket failures over a mean period of 8.9 months were recorded for each bracket and, subsequently, the chi-square test, the Yates-corrected chi-square test, the Fisher exact test, Kaplan-Meier survival estimates, and the log-rank test were employed in statistical analyses of the results. Results: No statistically significant difference in bond failure rate was found between APC brackets bonded with the halogen light-curing unit and those cured with LED light. However, significantly fewer bonding failures were noted in the maxillary arch (1.67%) than in the mandibular arch (4.35%) after each light-curing technique. Conclusions: The hypothesis cannot be rejected since use of an LED curing unit produces similar APC bracket failure rates to use of conventional halogen light, with the advantage of a far shorter curing time (10 seconds).

scholarly journals A Retrospective Clinical Audit of Bracket Failure among Patients Undergoing Orthodontic Therapy

2020 ◽  
Vol 2020 ◽  
pp. 1-5
Author(s):  
Dashrath Kafle ◽  
Rajeev Kumar Mishra ◽  
Md Riasat Hasan ◽  
Takashi Saito
Keyword(s):  
Failure Rate ◽  
Treatment Time ◽  
Class Iii ◽  
Chi Square ◽  
Delayed Treatment ◽  
Orthodontic Therapy ◽  
Bonding Failure ◽  
Significant Difference ◽  
Chi Square Test ◽  
Bracket Failure

Objective. Bonding failure is a problem in orthodontic therapy and has been associated with orthodontic emergencies and delayed treatment time. The aim of this study is to determine the bracket failure rate among patients undergoing orthodontic therapy. Materials and Methods. From the archives of posttreatment records, 200 total cases were selected, out of which 122 cases had detailed treatment records. Cases with incomplete records, large restorations, or enamel aberrations were excluded from the study. Descriptive statistics were applied to obtain sample characteristics, and a chi-square test was applied to compare the bracket failure between different categories. Result. Out of the 122 samples enrolled in the study, female and male patients comprised 71% and 29%, respectively. Class I malocclusions were the most common problem (56%), followed by Class II (41%) and Class III (3%). The bracket failure rate was 3.43%, and 32% of the patients had an incidence of bracket failure. There was no significant difference in bracket failure among genders ( p = 0.344 ), malocclusion types ( p = 0.191 ), or operators ( p = 0.188 ). The maxillary left quadrant was the most common site of bracket failure, followed by the mandibular right quadrant. Conclusion. Bracket failure is relatively uncommon. It is not affected by the gender or age of the patient or by malocclusion type. The maxillary left and mandibular right quadrants are the most common sites of bracket failure.

scholarly journals Clinical Evaluation of Bracket Bonding Using Two Different Polymerization Sources

2008 ◽  
Vol 78 (5) ◽  
pp. 922-925 ◽  
Author(s):  
Nikolaos S. Koupis ◽  
Theodore Eliades ◽  
Athanasios E. Athanasiou
Keyword(s):  
Failure Rate ◽  
Orthodontic Treatment ◽  
Light Emitting Diode ◽  
Rank Test ◽  
Dental Arch ◽  
Halogen Lamp ◽  
Failure Rates ◽  
Bond Failure ◽  
Significant Difference ◽  
The Right

Abstract Objective: To comparatively assess clinical failure rate of brackets cured with two different photopolymerization sources after nine months of orthodontic treatment. Materials and Methods: The sample of this study comprised 30 patients who received comprehensive orthodontic treatment by means of fixed appliances. Using the same adhesive, 600 stainless steel brackets were directly bonded and light cured for 10 seconds with the light-emitting diode (LED) lamp or for 20 seconds with the conventional halogen lamp. A split-mouth design randomly alternated from patient to patient was applied. Failure rates were recorded for nine months and analyzed with Pearson χ2 test, and log-rank test at α = .05 level of significance. Results: The overall failure rate recorded with the halogen unit (3.33%) was not significantly different from the failure rate for the LED lamp (5.00%). Significantly more failures were found in boys compared with girls, in the mandibular dental arch compared with the maxillary arch, and in posterior segments compared with anterior segments. However, no significant difference was found between the right and left segments. Conclusion: Both light-curing units showed sufficiently low bond failure rates. LED curing units are an advantageous alternative to conventional halogen sources in orthodontics because they enable a reduced chair-time bonding procedure without significantly affecting bond failure rate.

scholarly journals Prevalence of Congenitally Missing Permanent Teeth in Aseer, KSA

2017 ◽  
Vol 1 (2) ◽  
Keyword(s):  
Permanent Teeth ◽  
P Value ◽  
Fisher Exact Test ◽  
Missing Teeth ◽  
Chi Square ◽  
Cross Sectional ◽  
Significant Difference ◽  
Chi Square Test ◽  
Congenitally Missing Teeth ◽  
Congenitally Missing

Background: Hypodontia or congenitally missing teeth is among dental anomalies with different prevalence in each region. The aim of this study was to evaluate the prevalence of congenitally missing permanent teeth in Aseer region population. Materials and Methods: A descriptive, retrospective and cross-sectional study was done. Panoramic radiographs of 1050 patients (370 girls and 680 boys), 12-40 years old, were collected. The radiographs were studied for evidence of congenitally missing teeth. Data were analyzed using Paired t-test, Mann-Whitney test, Fisher exact test and Chi-square test (0.05). Results: Prevalence of congenitally missing teeth was totally 7.42%. The most frequent congenitally missing teeth was mandibular second premolars (28.21%) followed by maxillary second premolars (25.64%). Upper jaw showed significantly higher number of congenitally missing teeth (P value 0.001). According to Chi-square test, congenital missing teeth were found approximately 7.42% in both females and males and there were no statistically significant difference between sexes (P 0.19). Conclusion: The prevalence of congenitally missing teeth (CMT) in Aseer region permanent dentition was 7.42%. The most common congenitally missing teeth were mandibular second premolar fallowed by maxillary second premolars.

scholarly journals Comparison of Transmittance and Reflectance Pulse Oximetry in Anesthetized Dogs

2021 ◽  
Vol 8 ◽  
Author(s):  
Jan Nixdorff ◽  
Yury Zablotski ◽  
Katrin Hartmann ◽  
Rene Dörfelt
Keyword(s):  
Failure Rate ◽  
Pulse Oximeter ◽  
Matched Pair ◽  
Rank Test ◽  
Chi Square ◽  
Signed Rank ◽  
Signed Rank Test ◽  
Chi Square Test ◽  
Probe Site ◽  
Pulse Oximeter Probe

Objectives: The tongue is the standard site for placement of a pulse oximeter probe but is difficult to access during certain procedures such as dental and ophthalmic procedures and computerized tomography of the head. The aim of this study was to evaluate the performance of a new-generation reflectance pulse oximeter using the tail and tibia as sites for probe attachment.Materials and Methods: A total of 100 client-owned dogs that underwent anesthesia for various reasons were premedicated with butorphanol (n = 50; 0.2 mg/kg; group BUT) or butorphanol and dexmedetomidine (n = 50; 5 μg/kg; group DEX), administered intravenously. Anesthesia was induced with propofol and maintained with sevoflurane. A transmittance pulse oximeter probe was placed on the tongue and served as the reference standard. A reflectance probe was randomly placed on the tail base or the proximal tibia, and the position changed after testing. Signals from three consecutive measurements were obtained at each position. Failure was defined as “no signal,” “low signal,” or a pulse difference >10/min compared with the ECG heart rate. Data were analyzed using chi-square test, Wilcoxon matched-pair signed-rank test, and Bland-Altman analysis. P < 0.05 was considered significant.Results: In both groups (BUT and DEX), failure rate was higher when the tibia and tail were used as probe sites compared with the tongue. In both groups, the failure rate was higher for the tibia than for the tail. Dexmedetomidine-induced vasoconstriction increased failure rate at all probe positions.Clinical Significance: The tail base, but not the tibia, is an acceptable position for reflectance pulse oximeter probes in dogs. The tongue remains the probe site of choice, if accessible.

RADT-31. TREATMENT TRENDS AND SURVIVAL OUTCOMES IN ATYPICAL MENINGIOMA

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi48-vi48
Author(s):  
Yusef Syed ◽  
Manali Rupji ◽  
Jeffrey Switchenko ◽  
Bree Eaton ◽  
Jeffrey Olson ◽  
...  
Keyword(s):  
Survival Data ◽  
Cox Regression ◽  
Atypical Meningioma ◽  
Rank Test ◽  
Chi Square ◽  
Who Grade ◽  
Treatment Type ◽  
Significant Difference ◽  
Chi Square Test ◽  
Atypical Meningiomas

Abstract BACKGROUND WHO grade II (atypical) meningiomas are treated with surgical resection, often followed by adjuvant fractionated radiation therapy (FRT). The increased availability of frameless stereotactic radiosurgery (SRS) presents an opportunity to offer patients a high biological effective dose over fewer fractions. Here we study the patterns of care and outcomes of these two forms of adjuvant RT. METHODS Patients with atypical meningioma were abstracted from the National Cancer Database (NCDB). Descriptive statistics were reported, and differences between treatment groups were assessed using either a chi-square test or ANOVA. Patients were grouped by treatment type and Kaplan Meier (KM) analysis was performed to compare overall survival (OS) using a log rank test. Univariable (UVA) and multivariable (MVA) cox regression analyses were completed. RESULTS Of 10,015 cases diagnosed from 2004-2016, 7,153 received surgery alone, 2,059 received surgery and adjuvant FRT (S+RT), and 362 received adjuvant SRS (S+SRS). The use of adjuvant RT increased by 71.8% for S+RT and 97.8% for S+SRS. In 2004, 15.1% of 443 registered patients received S+RT and 2.26% received S+SRS, while in 2016 these figures were 26.0% and 4.47%, respectively, for the 1051 registered patients (p< 0.001 and 0.022, respectively). For the 8,636 patients with survival data there was no significant difference in median OS between S+RT and S+SRS (130 months vs. 125 months, log rank p=0.935). On UVA, S+RT conferred better survival compared to surgery alone (HR 0.81 [0.72-0.91], p< 0.001) while S+SRS trended towards better survival (HR 0.82 [0.64-1.06], p=0.124). On MVA, no significant OS benefit was seen with S+RT (HR 0.96 [0.85-1.08], p=0.491) or S+SRS (HR 0.90 [0.69-1.16], p=0.413) versus surgery alone. CONCLUSIONS While the use of adjuvant RT for atypical meningioma has increased substantially since 2004, OS is comparable between FRT and SRS. The data presented here support further prospective investigation of adjuvant SRS.

scholarly journals Survival Analysis of Hungarian Large White, Duroc and Pietrain Sows

2016 ◽  
pp. 31-36
Author(s):  
Ágnes Baginé Hunyadi ◽  
Szilvia Kusza ◽  
Péter Balogh
Keyword(s):  
Survival Analysis ◽  
Rank Test ◽  
Large White ◽  
Chi Square ◽  
Survival Percentage ◽  
Kaplan Meier ◽  
Significant Difference ◽  
Chi Square Test ◽  
Single Factor Analysis ◽  
The Individual

The aim of the present study was to perform lifetime performance analysis in three pig breeds; Hungarian Large White (n=295), Duroc (n=76) and Pietrain (n=91) on a commercial farm using analysis of survival sows. We took into consideration the age of sows at the time of their inclusion into breeding, their age at the time of culling, time spent in production, number of mating and parities, parity percentage, intervals between litters, number and mean of piglets born alive and born dead, number of raised piglet litters, number and mean of 21 days old piglets, the weight and mean of raised litter and raise percentage. We carried out the analysis by SPSS 22.0. Single factor analysis of variants, Kaplan-Meier analysis and Cox PH model were used. The determination of the significance of risk rates differences was done by Wald chi square test. Our results showed that the average culling age were 1056 (±33.52) days for the Hungarian Large White, 735 (±73.56) days for Duroc and 818 (±71.98) days for the Pietrain. The log rank test of the survival analysis indicated a significant difference between the three tested genotypes (χ2=16.981, P<0.001), which means that the survival percentage of the individual breeds varied significantly from one another. In comparison with the Hungarian Large White genotype the Duroc genotype has a 1.6 times higher (P<0.001) culling risk while that of the genotype Pietrain was 1.36 times higher (P<0.001). Our results can be used to compare the breeds kept under the same conditions and to compare the life span of one genotype under different farming conditions. Factors that increase survival and improve the profitability of pig farming can be determined by this method.

scholarly journals A hospital-based study of severe anemia in adults in Eastern India

2018 ◽  
Vol 7 (1) ◽  
pp. 114
Author(s):  
Subhash C. Dash ◽  
Naba K. Sundaray ◽  
Promod K. Tudu ◽  
Beeravelli Rajesh
Keyword(s):  
Iron Deficiency ◽  
Fisher Exact Test ◽  
Severe Anemia ◽  
Chi Square ◽  
Anemia Of Chronic Disease ◽  
Exact Test ◽  
Significant Difference ◽  
Chi Square Test ◽  
The Mean ◽  
Absolute Iron Deficiency

Background: Anemia remains a crucial health problem in developing countries. Cardiac compromise and fatal complications usually occur at Hb of <5g/dL. The aim of the study was to determine possible etiologic and clinical profile in adult patients with very severe anemia (Hb of <5g/dL).Methods: A prospective observational study was conducted in a teaching hospital of Odisha over a period of 12months. A total of 70 patients of both men and non-pregnant women admitted to the medicine wards were included after exclusion. Detailed history, clinical examination and investigation findings were recorded. Independent ‘t’ test, Wilcoxon rank sum test, Pearson chi-square test and Fisher exact test were used as applicable, to compare the variables.Results: The mean Hb (g/dL) was 3.73 ±0.85 and the mean age of the study group was 53.34±17.75years. No significant difference was observed in the severity of anemia between the female (mean Hb of 3.56±0.93) and male patients (mean Hb of 3.87±0.77) (p=0.130). The most frequent etiology found was absolute iron deficiency (44.3%, n=31) and mostly (41.9%) found in the age group of ≥65years (p<0.001). Congestive cardiac failure was found in 20% (n=14) of patients and majority of patients (64.2%, n=9) were males (p<0.001).Conclusions: Iron deficiency is the principal cause of very severe anemia in adults rather than malignancy or anemia of chronic disease and only about one fourth of patients develop heart failure even with very severe anemia.

Role of pulse plethysmograph in the prediction of hypotension in caesarean section patient under spinal anesthesia

2021 ◽  
Vol 19 (3) ◽  
pp. 77-80
Author(s):  
Sheetal K Desai ◽  
Keyword(s):  
Blood Pressure ◽  
Caesarean Section ◽  
Spinal Anesthesia ◽  
Characteristic Curve ◽  
Elective Caesarean Section ◽  
Rank Test ◽  
Chi Square ◽  
Significant Difference ◽  
Chi Square Test

Background: Spinal anesthesia is a commonly employed technique for anesthesia for caesarean section and is associated with hypotension which may cause maternal morbidity. Prediction of hypotension before the procedure can reduce complications. The study aimed to evaluate the role of pulse plethysmograph in the prediction of hypotension in caesarean section patients under spinal anesthesia. Methods: The observational study was conducted on 50 patients who were undergoing emergency or elective caesarean section. Spinal anesthesia was performed by anaesthesiologist using a 25 or 26-gauge spinal needle with bupivacaine at L3-4 interspinous space. Pre and post-anesthesia observations such as the width of pulse plethysmograph, non-invasive blood pressure in another arm, and heart rate were recorded. Paired T-test, Wilcoxon sign rank test, and chi-square test was used to analyse data using R Studio V 1.2.5001 software. Results: Post spinal anesthesia minor fall in systolic blood pressure (SBP) was observed in 11 patients, moderate fall in 21 patients, severe fall in 8 patients and a massive fall in 10 patients. A significant difference was observed between mean pre- and post-spinal anesthesia SBP (P<0.001). Width of pulse plethysmograph (PPG) was maintained in 14 patients whereas, narrowed and significantly narrowed PPGs were observed in 29 and 7 patients, respectively. Significant association was observed between grades of SBP and width of PPG (P<0.05). Receiver operating characteristic curve showed the width of PGG was good for prediction of hypotension in patient (AUC=0.828). Conclusion: Width of PPG can be used to predict SA induced maternal hypotension.

scholarly journals Ruxolitinib-treated polycythemia vera patients and their risk of secondary malignancies

2021 ◽  
Author(s):  
Rohit Sekhri ◽  
Parvis Sadjadian ◽  
Tatjana Becker ◽  
Vera Kolatzki ◽  
Karlo Huenerbein ◽  
...  
Keyword(s):  
Polycythemia Vera ◽  
Rank Test ◽  
Secondary Malignancies ◽  
Chi Square ◽  
Increased Risk ◽  
Single Center Study ◽  
Significant Difference ◽  
Chi Squared ◽  
Chi Square Test

AbstractRecently, there has been increased concern about a risk of secondary malignancies (SM) occurring in myelofibrosis (MF) patients receiving ruxolitinib (RUX). In polycythemia vera (PV), on the other hand, only limited data on the risk of SM under RUX treatment are available. To investigate the association between RUX therapy in PV and SM, we conducted a retrospective, single-center study that included 289 PV patients. RUX was administered to 32.9% (95/289) of patients for a median treatment duration of 48.0 months (range 1.0–101.6). Within a median follow-up of 97 months (1.0–395.0) after PV diagnosis, 24 SM occurred. Comparing the number of PV patients with RUX-associated SM (n = 10, 41.7%) with the 14 (58.3%) patients who developed SM without RUX, no significant difference (p = 0.34, chi square test) was found. No increased incidences of melanoma, lymphoma, or solid “non-skin” malignancies were observed with RUX (p = 0.31, p = 0.60, and p = 0.63, respectively, chi square test). However, significantly more NMSC occurred in association with RUX treatment (p = 0.03, chi-squared test). The “SM-free survival” was not significantly different by log rank test for all 289 patients (p = 0.65), for the patients (n = 208; 72%) receiving cytoreductive therapy (p = 0.48) or for different therapy sequences (p = 0.074). In multivariate analysis, advanced age at PV diagnosis (HR 1.062 [95% CI 1.028, 1.098]) but not administration of RUX (HR 1.068 [95% CI 0.468, 2.463]) was associated with an increased risk for SM (p = 0.005). According to this retrospective analysis, no increased risk of SM due to RUX treatment could be substantiated for PV.

scholarly journals Physical Education and Leisure Time Activities Among Pupils With and Without Hearing Loss

2021 ◽  
Vol 21 (2) ◽  
pp. 167-172
Author(s):  
Aneta Změlíková ◽  
Petra Kurková
Keyword(s):  
Hearing Loss ◽  
Physical Education ◽  
Leisure Time ◽  
Leisure Activities ◽  
Fisher Exact Test ◽  
Chi Square ◽  
Exact Test ◽  
Significant Difference ◽  
Chi Square Test ◽  
Schools For The Deaf

The objective of this study was to analyse differences among Czech pupils’ with/without hearing loss related to feelings and opinions on physical education classes; sport preferences in physical education classes; and leisure time activities at the lower secondary schools for the deaf.  Materials and methods. Participants were 83 pupils with hearing loss (n = 41; 49.4%) and pupils without hearing loss (n = 42; 50.6%); an average age of them was 14.3 ± 1.3 years. The non-parametric Mann-Whitney U-test, Fisher exact test, Chi-square test were used for statistical analyses. For calculation of effect size coefficient abs(r) was used. All tests were performed at a level of 0.05.  Results. Pupils without hearing loss are more likely to express disappointment due to cancellation of a physical education class than pupils without hearing loss (Z = –2.168; p = 0.029). A statistically significant difference was found in preference for the various physical education activities and in leisure activities, where pupils without hearing loss prefer dancing (χ2 = 8.622; p = 0.003), whereas pupils with hearing loss prefer volleyball (χ2 = 14.833; p = 0.00001). In terms of leisure time activities, pupils with hearing loss spent their leisure time watching television significantly more often (χ2 = 5.198; p = 0.023).  Conclusion. Both groups do not differ in feelings and opinions on physical education in terms of popularity, difficulty, importance, effort during physical education. On the contrary, differences in feelings associated with the cancellation of physical education or preference of activities in physical activities in physical education and leisure time appeared.

Sign in / Sign up

Export Citation Format

Share Document