Assessment of the convergence angle of teeth prepared for full crown by preclinical dental students

2021 ◽  
pp. 6399-6404
Author(s):  
Amaweya Abdulrahman Al-Sammarraie ◽  
Ayyam Khalid Abdulkareem ◽  
Hadeel Rateb AlAridi ◽  
Rahel Fayez Hammad ◽  
Duaa Yousef Shehadeh
Keyword(s):  
Dental Students ◽  
T Test ◽  
Ideal Convergence ◽  
Convergence Angle ◽  
Paired Samples ◽  
Mean Convergence ◽  
Significant Difference ◽  
Normal Convergence ◽  
The Mean ◽  
One Way Anova

The objective of this study was to measure the buccolingual and mesiodistal convergence angles of six typodont teeth (# 26, 36, 45, 15, 21, and 13), prepared by preclinical dental students at Ajman University, for porcelain fused to a metal full crown and to compare them with the recommended convergence angle (6.5°). Additionally, we sought to compare the angles recorded for the six sets of teeth and relate the results according to the tooth position and surface and to know which one shows the greater tendency of straying from the normal convergence angle. Materials and methods: The angle of convergence of one hundred ninety-eight typodont teeth preparations was measured both buccolingually and mesiodistally by using a Dino-lite pro digital microscope (AM-413ZT Taiwan) with a Dinocapture (2.0 version 1.5.27.A, AnMo Electronics Corporation). All the results were recorded, and the data were analyzed by means of a one-sample t-test and one-way ANOVA. Results: The mean total convergence angle for this study was 11.29°± 6.66° from both surfaces, which is greater than the recommended value of 6.5° and statistically significant (p<0.000). Only 7.07% of teeth met the ideal convergence angle from both surfaces, and the one-sample test showed a statistically significant difference (p<0.057) from the recommended convergence angle, except for the mesiodistal convergence angle of the lower-right second premolar, which revealed no significant difference. The mean convergence angle for the buccolingual surface was 12.42°± 6.16°, which was higher than that of the mesiodistal surface (10.16°± 7°). One-way ANOVA showed a significant difference between all selected teeth (p<0.000), and a paired samples t-test showed a significant difference within two teeth only, the lower-right second premolar and upper-right canine (p<0.000), in which the mesiodistal measurement showed a lower convergence angle than the buccolingual angle. Conclusions: Preclinical students prepared teeth with a convergence angle higher than the recommended convergence angle. However, all the recorded angles were within the range of previous studies. It was concluded that the recommended convergence angle was difficult to achieve in preclinical practice.

scholarly journals Impact of Concrete-Pictorial-Abstract Approach with Collaborative Lesson Research on Year Four Pupils’ Proficiency in Perimeter

2021 ◽  
Vol 29 (4) ◽  
pp. 2301-2313
Author(s):  
Mohd Shafian Shafiee ◽  
Cheng Meng Chew
Keyword(s):  
Test Scores ◽  
Random Sampling ◽  
T Test ◽  
Paired Samples ◽  
Abstract Approach ◽  
Significant Difference ◽  
Post Test ◽  
The Mean ◽  
One Way Anova ◽  
Cluster Random Sampling

The purpose of this study was to determine whether the concrete-pictorial-abstract (CPA) approach developed based on the Collaborative Lesson Research (CLR) cycles can positively impact Year Four pupils’ proficiency in perimeter. Counterbalanced design was used with pre- and post-test in every CLR cycle. The participants involved were three groups of pupils totaling 115 pupils and a group of three teachers. The sampling used was cluster random sampling. A paired-samples t test was used to determine whether there is a significant difference between the pre- and post-test for each CLR cycle while a one-way ANOVA test was used to analyze if there is an increase in proficiency from the first, second and third CLR cycles. The results indicated that there was an increase in the mean post-test scores compared to the mean of pre-test scores and the mean difference between the first, second and third CLR cycles. In conclusion, the CLR cycle carried out helped teachers in developing better teaching plans based on the CPA approach as well as enhancing pupils’ proficiency in the perimeter.

scholarly journals Productive and Receptive Collocational Knowledge of Iranian EFL Learners at Different Proficiency Levels

2017 ◽  
Vol 6 (7) ◽  
pp. 11
Author(s):  
Fahimeh Talakoob ◽  
Mansour Koosha
Keyword(s):  
Test Scores ◽  
T Test ◽  
Placement Test ◽  
Efl Learners ◽  
Proficiency Levels ◽  
Paired Samples ◽  
Significant Difference ◽  
Intermediate Learners ◽  
The Mean

In the present study, an attempt was made to probe into the probable difference between Iranian intermediate and advanced EFL learners' receptive and productive collocational knowledge. To this end, 60 EFL learners studying at Islamic Azad University, Isfahan Branch, including 30 advanced and 30 intermediate learners, were chosen through the Oxford Placement Test (OPT). The participants at each level of proficiency received two tests of collocations, namely receptive collocation test and productive test of collocations. Paired-samples t test showed no statistically significant difference between productive and receptive knowledge of collocations of the advanced EFL learners. However, the mean comparison between the receptive and productive collocation test scores of intermediate EFL learners revealed a significant difference. Pedagogical implications emanating from the obtained results are elaborated in the study.

A Different DNA Methylation Profile is Obtained from a Recently Published MZ Study of Psychiatry

2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1
Author(s):  
M. Liang ◽  
Y. Hu ◽  
D. Chen
Keyword(s):  
Dna Methylation ◽  
Birth Weight ◽  
Monozygotic Twins ◽  
Methylation Profile ◽  
T Test ◽  
Paired Samples ◽  
Significant Difference ◽  
Dna Methylation Profile ◽  
Analysis Strategy ◽  
The Mean

Aim:To get a more robust DNA methylation profile from the data given by a published article of a MZ study of psychiatry.Method:Considering the relevance of birth weight with DNA methylation profiles, we reanalyzed the data from the paper of Mill etc. (DOI: 10.1002/ajmg.b.30316) with rearrangement of the group order within twin pair, prior if lighter in birth weight. Statistical methods used are including mean, correlation and paired-samples t-test (considering twins’ particularity).Results:We calculated twin difference by lighter twin's methylation percentage minus that of heavier twin. The mean of CpG1 methylation differences is -7.08% while -7.17% for CpG2. The two means have no statistical significant difference in a paired-samples t-test (t=0.027, p=0.979, 2-tailed). These results are different from the original paper: 10.3% for CpG1 and 16.1% for CpG2, which are statistical significantly different (t=-2.792, p=0.018, 2-tailed). Besides, we found that in the lighter twin group, the methylation percentage are statistical significantly different between CpG1 and CpG2 (t=2.627, p=0.024, 2-tailed). As to correlation analysis, we got a slightly different result: correlation between MZ differences in two sites is weaker after rearrangement (r=0.875, while r=0.913 before arrangement, both p< 0.001).Conclusion:According to our study, the results imply that twin differences may not be the only thing worthy of investigation. Different patterns among CpGs in certain kinds of subgroups should also need attention. We need conduct a robust data analysis strategy in our researches on the epigenetic aspects of psychiatry, where monozygotic twins have a favorable utility.

scholarly journals Comparison of the Infertility-Related Stress Among Couples and its Relationship With Infertility Factors

2018 ◽  
Vol 7 (3) ◽  
pp. 313-318 ◽  
Author(s):  
Razhan Chehreh ◽  
Giti Ozgoli ◽  
Khadijeh Abolmaali ◽  
Malihe Nasiri ◽  
Elahe Mazaheri
Keyword(s):  
Treatment Failure ◽  
Cross Sectional Study ◽  
T Test ◽  
Social Concern ◽  
Cross Sectional ◽  
Paired Samples ◽  
Significant Difference ◽  
The Mean ◽  
Inducing Factors ◽  
Related Stress

Objectives: Inability to have a child is stressful and affects all aspects of couples’ lives. Infertility diagnosis, duration and reason of infertility, treatment failure, and frequent pregnancy tests are among the stress-inducing factors in couples. The current study aimed to compare infertility-related stress among couples and evaluate its relationships with infertility factors. Materials and Methods: This cross-sectional study was performed on 150 infertile couples (300 individuals) visiting infertility centers of Tehran. The data were collected using the Fertility Problem Inventory (FPI) and fertility and demographic characteristics form. The subjects were selected through convenience sampling method. The data were analyzed through inferential statistics, including paired samples t-test, independent samples t test, ANOVA, and linear regression. Results: According to the results, the mean stress score of women was significantly higher than that of the men (P=0.007). There was a significant difference between males and females regarding the mean scores of social concern and need for parenthood (P=0.005). The mean score of infertility-related stress was also significantly higher in women with treatment failure than in men (P=0.01). Conclusions: Based on the findings of the present study, infertile women experienced greater stress than males. Furthermore, infertility-related stress increased in women due to treatment failure. Therefore, it is recommended that women who have experienced treatment failure be subjected to precise psychological evaluations before undergoing the treatment process.

scholarly journals THE EFFECTIVENESS OF ZINC AND RISEDRONATE ON BONE TURNOVER IN RAT MODEL OF OSTEOPOROSIS ASSESSED WITH THE EXPRESSION OF β-CROSSLAPS

2019 ◽  
Vol 7 (2) ◽  
pp. 114
Author(s):  
Adam Fajar ◽  
Mohammad Rizal Chaidir ◽  
Dicky Mulyadi ◽  
Ahmad Ramdan ◽  
Yoyos Dias Ismiarto
Keyword(s):  
Bone Turnover ◽  
Blood Sample ◽  
Rat Model ◽  
Bone Structure ◽  
Comparative Method ◽  
T Test ◽  
Term Therapy ◽  
Significant Difference ◽  
The Mean ◽  
One Way Anova

Background: Osteoporosis prevalence in Indonesia is high. Risedronate commonly used for treating the osteoporosis. Unfortunately, long term therapy can cause hazardous adverse effect to the patient. Previous research in rat model osteoporosis, Zinc have a potential effect to prevent and rebuild bone structure with osteoblast stimulation in bone formation and osteoclast activity inhibition in bone resorption by increasing Osteoprotegerin production, that inhibit bond between RANKL and RANK.Purpose: To determine the effectiveness of Zink and Risedronate on bone turnover in osteoporotic model rats assessed the β-CrossLaps expression.Methods: This research is conducted as experimental comparative method used 25 female Galur Wistar rat that divided into Non-ovariectomy and Ovariectomy group to induce osteoporosis. The treatment is divided into Zinc-Risedronate, and Zinc, or Risedronate only. One Way Anova and Independent T-test was used to analyzed the significant difference between groups.Result: One Way Anova statistic test forβ-CrossLaps expression value in the 3rd Taken blood sample showed that p is less than 0.05 (p<0.05), which indicated that are significant difference in the mean between variable at 3rd Taken blood sample in all group. Meanwhile, Independent T-test was used to compare β-CrossLaps expression in 3rd taken blood sample between Ovari and Ovari+Zinc, Ovari and Ovari+Zinc+Rise showed p is less than 0.05 (p<0.05), which indicated that there are significant difference in the mean between variable 2 groups.Conclusion: Zinc-Risedronate administration will decrease bone turnover and β-CrossLaps expression more than Zinc or Risedronate only in rat model osteoporosis.

scholarly journals Comparison of Enamel Demineralisation Scores between Passive Self-Ligation Brackets and Conventional Ligation Brackets in Patients Undergoing Orthodontic Treatment- A Laser Fluorescence Study

2020 ◽  
Author(s):  
Akriti Tiwari ◽  
Ravindra Kumar Jain
Keyword(s):  
Orthodontic Treatment ◽  
T Test ◽  
Laser Fluorescence ◽  
Anova Test ◽  
Significant Difference ◽  
The Mean ◽  
Gender Association ◽  
T1 And T2 ◽  
The Difference ◽  
One Way Anova

Introduction: Enamel demineralisation is often seen in patients undergoing fixed orthodontic treatment because appliances create retentive areas around the brackets leading to food debris accumulation. The method of ligation is also an additional factor in causing plaque accumulation leading to demineralisation around the brackets. Aim: The present study aims to compare enamel demineralisation around self-ligation brackets and conventional ligation brackets at the 3rd month and 12th month of orthodontic treatment using laser fluorescence. Materials and Methods: The present prospective study aims to compare enamel demineralisation around self-ligation brackets (Damon 3mx) and conventional ligation brackets (Gemini 3M) at the 3rd month and 12th month of orthodontic treatment using laser fluorescence. Nineteen subjects who were scheduled for fixed orthodontic treatment were selected for the study and were divided into two groups that is conventional ligation and passive self-ligation. Diagnodent (DD) was used to take enamel demineralisation scores at the time of bonding (T0), 3 months (T1) and 12 months (T2) into treatment. All statistical analysis was performed using IBM SPSS version 20. Chi-square test was performed to find the gender association, One-way ANOVA test was carried out to evaluate the difference of DD scores at time period T0, T1 and T2 in self-ligation group and conventional ligation group and Independent t-test was carried out to evaluate the difference of DD scores between self-ligation brackets and conventional ligation at T0, T1 and T2. Results: One-way ANOVA test reported that in conventional ligation groups there was a statistically significant difference in the mean DD scores between T0 and T1, T0 and T2 (p<0.05). Similarly, in the self-ligation group, a statistically significant difference was observed in the mean DD score between T0 and T1, T0 and T2 (p<0.05). Independent t-test to evaluate the difference of mean DD scores between self-ligation brackets and conventional ligation at T2 was found to be statistically non-significant (p>0.05). No gender association was noted. Conclusion: The method of ligation did not influence enamel demineralisation around orthodontic brackets.

Estimating the pH of Commercially Available Dentifrices and Evaluating its Effect on Salivary pH After Brushing

2013 ◽  
Vol 7 (1) ◽  
pp. 12-16 ◽  
Author(s):  
P Gulati ◽  
S Dhingra ◽  
S Chand ◽  
Swatika LNU
Keyword(s):  
Study Groups ◽  
T Test ◽  
Significant Difference ◽  
Active Salt ◽  
Different Types ◽  
Salivary Ph ◽  
Before And After ◽  
The Mean ◽  
One Way Anova ◽  
Paired T Test

ABSTRACT Objectives The purpose of the study was to estimate the pH of commercially available dentifrices and evaluating its effect on salivary pH after brushing Material and Methods 60 study subjects were selected and were divided into 12 groups (each group comprises of 5 subjects). The salivary pH was directly estimated using the digital pH meter calibrated using buffers of pH 4, 7 and 22. Paired t test was used to compare the changes in the mean salivary pH after brushing in each group. One way ANOVA and Tukey's test was used to compare the changes in mean salivary pH after brushing between different groups. Results pH of different types of commercially available dentifrices which were used in the study was found to be 8.4, 7.9, 7.9, 6.7, 7.2, 8.3, 8.4, 7.1, 6.5, 5.6, 8.2 and 6.5 respectively. Difference in mean salivary pH after brushing was found to be statistically significant for Colgate, Neem active group, Vicco, Triguard, Colgate active salt, Dabur meswak, Dabur babool, Close-up active gel, RA Thermoseal, Dabur lal dant manjan, Colgate powder groups. Mean salivary pH (before and after brushing) between study groups showed a statistically significant difference. Conclusion The pH of saliva increases after brushing in each commercially available dentifrice group.

scholarly journals The Effect of Hope Therapy-based Training on the Happiness of Women with Breast Cancer: A Quasi-experimental Study

2021 ◽  
Vol 9 (4) ◽  
Author(s):  
Niloofar Kondori Fard ◽  
Asadollah Keikhaei ◽  
Maliheh Rahdar ◽  
Nasrin Rezaee
Keyword(s):  
Breast Cancer ◽  
Experimental Study ◽  
Intervention Group ◽  
T Test ◽  
Control Group ◽  
Paired Samples ◽  
Significant Difference ◽  
Quasi Experimental ◽  
The Mean ◽  
Hope Therapy

Background: The prevalence of cancer and its psychological consequences has increased steadily in recent decades. Hence, parallel to providing medical interventions, psychological therapies should be provided to cancer patients. Objectives: The present study aimed to determine the effect of hope therapy-based training on the happiness of women with breast cancer. Methods: In this quasi-experimental study, 100 female patients with breast cancer admitted to the chemotherapy wards of two hospitals affiliated to the Zahedan University of Medical Sciences (Iran) in 2020 are studied. Participants were selected using the convenience sampling technique and randomly divided into two groups of intervention and control (each with 50 subjects). The intervention group received eight sessions of group-based hope therapy training. Data were collected using a demographic information form and the Oxford Happiness questionnaire. Data were analyzed using SPSS version 16 by chi-square, independent samples t-test, and paired samples t-test, at a significant level of P < 0.05. Results: There was no significant difference between the two groups concerning demographic characteristics. The independent samples t-test showed no significant difference in the mean scores of happiness between the two groups before the intervention (P = 0.55). However, the mean score of happiness for the participants in the intervention group showed a significant increase after providing the intervention compared to the control group (P = 0.001). Besides, the paired samples t-test indicated a significant increase in the mean score of happiness after providing the intervention compared to before intervention (P = 0.001), while the mean score of happiness for the participants in the control group showed a statistically significant decrease (P = 0.004). Conclusions: This study demonstrated that hope therapy-based training is effective for the happiness of women with breast cancer. Since physical and psychological problems caused by cancer lead to sadness and reduced happiness, hope therapy can be added to the care programs for women with cancer undergoing chemotherapy.

Employing Personal Reading Logs through Short Stories to Enhance Students’ L2 Reading Comprehension Achievement

2019 ◽  
Vol 3 (2) ◽  
pp. 1
Author(s):  
Eliyas Sulaiman Mohandas ◽  
Nik Mastura Nik Ismail Azlan ◽  
Salwa Othman ◽  
Muhammad Aizat Azhari
Keyword(s):  
Short Stories ◽  
Reading Comprehension ◽  
P Value ◽  
L2 Reading ◽  
Reading Score ◽  
Paired Samples ◽  
Significant Difference ◽  
Post Test ◽  
The Mean ◽  
L2 Reading Comprehension

This study aims to investigate whether the use of six selected short stories throughout the duration of a 14-week course could enhance students’ reading comprehension achievement at the end of the semester. Out of the six short stories read, three were chosen as in-class assignments known as ‘Personal Reading Logs’ (hereafter, PRLs). One group of semester two Diploma students taking a reading skills course was selected through a convenience sampling method. A pre-test was conducted by having the students answer a past semester reading quiz of which the results would then be compared to their post-test (final reading exam) results. A paired samples t-test revealed no significant difference in the reading scores of the pre-test and the post-test, t (17) = -.265, p > .05. Since the p-value was bigger than 0.05, this indicated that the mean reading score of the post-test (M = 50.556) was not significantly higher than the mean reading score of the pre-test (M = 49.722). Therefore, the null hypothesis which stated that there was no difference in the mean score of the pre-test and post-test was retained. Overall, the result refuted the findings of other studies promoting the effectiveness of using short stories to enhance L2 reading comprehension achievement.

scholarly journals Pattern of symptom improvement following endoscopic sinus surgery for chronic rhinosinusitis

BMC Surgery ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Salma S. Al Sharhan ◽  
Mohammed H. Al Bar ◽  
Shahad Y. Assiri ◽  
Assayl R. AlOtiabi ◽  
Deemah M. Bin-Nooh ◽  
...  
Keyword(s):  
Surgical Outcomes ◽  
Endoscopic Sinus Surgery ◽  
T Test ◽  
Sinus Surgery ◽  
Symptom Improvement ◽  
P Value ◽  
Psychological Dysfunction ◽  
Significant Difference ◽  
The Mean ◽  
Snot 22

Abstract Background Chronic rhinosinusitis (CRS) is a common inflammation of the nose and the paranasal sinuses. Intractable CRS cases are generally treated with endoscopic sinus surgery (ESS). Although the effect of ESS on CRS symptoms has been studied, the pattern of symptom improvement after ESS for CRS is yet to be investigated. The aim of this study was to determine the magnitude and sequence of symptom improvement after ESS for CRS, and to assess the possible preoperative factors that predict surgical outcomes in CRS patients. Methods This was a longitudinal prospective study of 68 patients who had CRS (with or without nasal polyps). The patients underwent ESS at King Fahd Hospital of the University, Al Khobar, Saudi Arabia. The Sino-nasal Outcome Test-22 (SNOT-22) questionnaire was used for assessment at four time points during the study: pre-ESS, 1-week post-ESS, 4 weeks post-ESS, and 6 months post-ESS. Results The difference between the mean scores recorded for the five SNOT-22 domains pre-ESS and 6 months post-ESS were as follows: rhinologic symptoms (t-test = 7.22, p-value =  < 0.001); extra-nasal rhinologic symptoms (t-test = 4.87, p-value =  < 0.001); ear/facial symptoms (t-test = 6.34, p-value =  < 0.001); psychological dysfunction (t-test = 1.99, p-value = 0.049); and sleep dysfunction (t-test = 5.58, p-value =  < 0.001). There was a significant difference between the mean scores recorded for the five domains pre-ESS and 6 months post-ESS. Rhinologic symptoms had the largest effect size (d = 1.12), whereas psychological dysfunction had the least effect size (d = 0.24). The only statistically significant difference in the SNOT-22 mean scores recorded 4 weeks post-ESS was observed between allergic and non-allergic patients (t = − 2.16, df = 66, p = 0.035). Conclusion Understanding the pattern of symptom improvement following ESS for CRS will facilitate patient counselling and aid the optimization of the current treatment protocols to maximize surgical outcomes and quality of life. Level of evidence Prospective observational.

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