scholarly journals A theoretical analysis of longitudinal temporomandibular joint compressive stresses and mandibular growth

2021 ◽  
Author(s):  
Riddhi J. Desai ◽  
Laura R. Iwasaki ◽  
Sohyon M. Kim ◽  
Hongzeng Liu ◽  
Ying Liu ◽  
...  

ABSTRACT Objectives To determine if temporomandibular joint (TMJ) compressive stresses during incisor biting (1) differed between growing children over time, and (2) were correlated with Frankfort Horizontal-mandibular plane angle (FHMPA, °) and ramus length (Condylion-Gonion (Co-Go), mm). Materials and Methods Three-dimensional anatomical geometries, FHMPA and Co-Go, were measured longitudinally from lateral and posteroanterior cephalographs1 of children aged 6 (T1), 12 (T2), and 18 (T3) years. Geometries were used in numerical models to estimate subject-specific TMJ eminence shape and forces for incisor bite-forces of 3, 5, and 8 Newtons at T1, T2, and T3, respectively. TMJ compressive stresses were estimated via two steps: First, TMJ force divided by age-dependent mandibular condylar dimensions, and second, modified by loading surfaces' congruency. Analysis of variance and Tukey honest significant difference post-hoc tests, plus repeated measures and mixed effects model analyses were used to evaluate differences in variables between facial groups. Regression analyses tested for correlation between age-dependent compressive stresses, FHMPA, and Co-Go. Results Sixty-five of 842 potential subjects had T1-T3 cephalographs and were grouped by FHMPA at T3. Dolichofacial (FHMPA ≥ 27°, n = 36) compared to meso-brachyfacial (FHMPA< 27°, n = 29) subjects had significantly larger FHMPA at T1-T3, shorter Co-Go at T2 and T3 (all P < .01), and larger increases in TMJ compressive stresses with age (P < .0001). Higher compressive stresses were correlated with larger FHMPA (all R2 ≥ 0.41) and shorter Co-Go (all R2 ≥ 0.49). Conclusions Estimated TMJ compressive stress increases from ages 6 to 18 years were significantly larger in dolichofacial compared to meso-brachyfacial subjects and correlated to FHMPA and Co-Go.

Author(s):  
Tayebe Ziaei ◽  
Maryam Ghanbari Gorji ◽  
Naser Behnampour ◽  
Masumeh Rezaei Aval

AbstractBackgroundSex dialogue is one of the most critical and challenging topics between mothers and adolescents. The knowledge and skills of mothers in sex dialogue with their daughters are essential. The purpose of this study is to determine the effect of group counseling based on communication skills on mothers through their sex dialogue with their daughters.MethodsA randomized controlled field trial was conducted on 168 couples of mothers and their daughters selected by the stratified matching method and randomly divided into two control and intervention groups. The mothers in the intervention group participated in a communication-based consultation in groups consisting of 6–12 people for 6–7 weekly sessions, each one lasting 60 min. The data collection tool was a Persian-translated questionnaire by Jaccard for sex dialogue between mother and daughter. The data were analyzed using Chi-square (χ2), ANOVA with repeated measures and modified post hoc Bonferroni tests.ResultsThere was a significant difference in the mean score of mother-daughter sex dialogue 1 week after intervention between the intervention (34.48 ± 8.74) and control (40.44 ± 9.49) groups (p = 0.001) and 1 month after the intervention between the intervention (30.41 ± 10.07) and control (42.47 ± 9.62) groups (p < 0.001).ConclusionThrough applying communication skills, an increase in mother-daughter sex dialogue frequency was observed after group counseling. Therefore, it is suggested to promote mother-daughter communication skills by accessing the mothers via schools, health centers and with the aid of midwifery counselors, midwives and other trained caretakers.


2003 ◽  
Vol 15 (4) ◽  
pp. 383-391 ◽  
Author(s):  
Theophanis Siatras ◽  
Georgios Papadopoulos ◽  
Dimitra Mameletzi ◽  
Vasilios Gerodimos ◽  
Spiros Kellis

Although warm-up and stretching exercises are routinely performed by gymnasts, it is suggested that stretching immediately prior to an activity might affect negatively the athletic performance. The focus of this investigation was on the acute effect of a protocol, including warm-up and static and dynamic stretching exercises, on speed during vaulting in gymnastics. Eleven boys were asked to perform three different protocols consisting of warm-up, warm-up and static stretching and warm-up and dynamic stretching, on three nonconsecutive days. Each protocol was followed by a “handspring” vault. One-way analysis of variance for repeated-measures showed a significant difference in gymnasts’ speed, following the different protocols. Tukey’s post hoc analysis revealed that gymnasts mean speed during the run of vault was significantly decreased after the application of the static stretching protocol. The findings of the present study indicate the inhibitory role of an acute static stretching in running speed in young gymnasts.


2017 ◽  
Vol 38 (10) ◽  
pp. 776-780 ◽  
Author(s):  
Anna Laws ◽  
Sean Williams ◽  
Cassie Wilson

AbstractBiomechanical imbalances and inefficient functional movements are considered contributing factors to running-related injuries. Clinical Pilates uses a series of exercises focused on retraining normal movement patterns. This study investigated whether a 6-week course of Clinical Pilates improves functional movement and thereby, potentially, reduces the risk of running-related injuries associated with movement dysfunction. A modified functional movement screen was used to analyze the functional movement ability of forty runners. Forty participants completed a 6-week course of Clinical Pilates delivered by a Clinical Pilates instructor. The movement screen was carried out 3 times for each runner: 6 weeks pre-intervention (baseline), within one week pre-intervention (pre) and within one week post-intervention (post). Repeated-measures analysis of variance and post-hoc tests found significant increases in scores between baseline and post (mean±SD; 13.4±2.4 vs. 17.0±1.7, p<0.01) and pre and post (mean±SD; 13.5±2.5 vs. 17.0±1.7, p<0.01), but no significant difference between baseline and pre (p=0.3). A 6-week course of Clinical Pilates significantly improves functional movement in recreational runners, and this may lead to a reduction in the risk of running-related injuries.


2019 ◽  
Vol 21 (1) ◽  
pp. 31-38
Author(s):  
Safar Abdi ◽  
Tayebeh Sharifi ◽  
Ahmad Qazanfari ◽  
Kamal Solati

Background and aims: Irrational beliefs in brilliant talent students can influence their psychological hardiness and lead to adverse social and academic outcomes. The present study mainly aimed to compare the effectiveness of group reality therapy and positive psychotherapy in improving the irrational beliefs and psychological hardiness of male brilliant talent high school students in Shahrekord during 2017. Methods: The present experimental research, used pretest and posttest design including intervention and control groups. The study population included all the male gifted students in Shahrekord (N=276) who were first screened and then, 60 individuals were selected by convenience random sampling. Next, the individuals were assigned a number and then divided into two experimental groups (each containing 20 students) and one control group (including 20 students) using a random number table. Afterward, group reality therapy and positive psychotherapy interventions were performed within eight and ten weeks for the experimental groups, respectively. In addition, Jones Irrational Beliefs Test (IBT) and Kobasa’s Psychological Hardiness Scale were employed to data collection. Six months after post-test implementation, the students were followed up. Finally, the data were analyzed using repeated-measures ANOVA and Bonferroni post hoc test. Results: The findings revealed that group reality therapy and positive psychotherapy led to a decrease in irrational beliefs while such therapies improved psychological hardiness in brilliant talent students (P<0.001). Conversely, the results of the post-hoc test indicated no significant difference between the effects of group reality therapy and positive psychotherapy on irrational beliefs and psychological hardiness in brilliant talent students (P>0.05). Conclusion: In general, group reality therapy and positive psychotherapy reduced irrational beliefs whereas they improved psychological hardiness of the brilliant talent students and therefore, these therapies can be used as effective interventions for the intended population.


2021 ◽  
Vol 31 (1) ◽  
pp. 35-43
Author(s):  
Shahab Papi ◽  
◽  
Yadollah Abolfathi Momtaz ◽  
Mahshid Foroughan ◽  
Farahnaz Mohammadi Shahboulaghi ◽  
...  

Introduction: Regular physical activity is very effective in preventing or delaying chronic diseases and premature death in the elderly. Objective: This study aimed to compare the effect of face-to-face education and e-learning methods on the physical activity of the elderly. Materials and Methods: This is a quasi-experimental study conducted in Karaj, Iran in 2018. The participants were 88 elderly people referred to a senior rehab center and then were assigned into three groups of face-to-face education (n=30), e-learning (n=28), and control (n=30).The study data were collected by a demographic form and the 41-item community healthy activities program for seniors questionnaire (CHAMPS) before the intervention, 1 month after the intervention, and 3-month follow-up. Face-to-face education and e-learning were presented to the two educational groups’ during eight 20-minute sessions. The obtained data were analyzed using ANOVA, Bonferroni post hoc test, the Chi-square test, and repeated measures ANOVA. The significance level was set at0.05. Results: Between the two educational groups, a significant difference was observed in the mean score of physical activity at three measurement phases (P = 0.001).The effect size was 0.61 for face-to-face education and 0.64 for e-learning. Based on the results of the Bonferroni post hoc test, there was no significant difference between e-learning and face-to-face education groups. Conclusion: Both face-to-face and e-learning methods were effective in promoting the physical activity behavior of the elderly. E-learning method can be used as one of the complementary methods of traditional education for improving the physical activity of the elderly.


2019 ◽  
pp. 030573561987849 ◽  
Author(s):  
Abbey L Dvorak ◽  
Eugenia Hernandez-Ruiz

The purpose of this study was to compare the effectiveness of and preference for different auditory stimuli in supporting mindfulness meditation. Undergraduate non-musicians ( N = 57) listened to four different auditory stimuli guiding them in a mindfulness meditation: script only (i.e., Script), steady beat (i.e., Beat), beat and harmonic progression (i.e., Harmony), and beat, harmony, and melody (i.e., Melody). This study used a within-subjects repeated-measures design with the four conditions counterbalanced and randomized across participants. Participants rated responses using the Mindful Attention Awareness Scale (MAAS), completed the Absorption in Music Scale (AIMS), and ranked auditory stimuli according to preference and usefulness for mindfulness meditation. A repeated-measures analysis of covariance (ANCOVA) on the MAAS scores, using the AIMS as a covariate, indicated no statistically significant difference between auditory stimuli. However, with the AIMS removed, the analysis revealed significant differences between stimuli, indicating that levels of absorption in music may moderate participants’ responses to auditory stimuli for mindfulness meditation. Friedman analyses of variance (ANOVAs) and post hoc analyses indicated that participant rankings of usefulness and preference were significantly different among conditions, with the Melody and Harmony conditions ranked highest.


2019 ◽  
Vol 28 (7) ◽  
pp. 429-435 ◽  
Author(s):  
Ambreen Chohan ◽  
Lauren Haworth ◽  
Simon Sumner ◽  
Mairi Olivier ◽  
Daniel Birdsall ◽  
...  

Objective: Compression devices have been shown to reduce venous stasis, increase blood flow and skin tissue oxygenation (StO2), promoting healthy tissue. This study aimed to explore the efficacy of a new compression garment in three different positions in healthy adults. Methods: In this quantitative study, potential participants were screened and recruited using the Physical Activity Readiness Questionnaire (PAR-Q, Canada). Participants attended three separate, one-hour sessions to evaluate StO2 in supine-lying, chair-sitting and long-sitting positions. StO2 was recorded for 20 minutes pre-, during and post- a 20-minute intervention using a compression garment, TributeWrap (Lohmann-Rauscher, Germany). A repeated-measures analysis of variance (ANOVA) was followed by post-hoc pairwise comparisons. Results: A total of 28 healthy volunteers took part (aged 24.6 ±8.4years; 13 males, 15 females). A significant difference was seen between the three positions (p<0.001). Chair-sitting had the lowest StO2 pre-intervention, increasing StO2 significantly (32.25%, p<0.001) during wear of the compression garment (24.8% higher than baseline post-intervention). No significant difference was seen between long sitting and supine-lying (p=1.000). In contrast, long-sitting and supine-lying StO2 was higher pre-intervention compared with chair-sitting and only increased post-intervention (11% and 16.8% respectively, p<0.001) compared with baseline. Conclusion: The compression garment significantly increased StO2 levels in both seating positions. Further studies are required to determine if increasing StO2 through short intervention sessions with this device has the potential to improve self-management of tissue health in individuals with reduced mobility, oedema or venous insufficiency.


2021 ◽  
pp. 030573562198897
Author(s):  
Aaron Lohmeyer

The primary purposes of this study were (1) to determine the effect of three encoding conditions (singing, playing, studying silently) on participants’ music memorization accuracy; (2) to examine potential differences between choral, jazz, and concert band musicians’ accuracy in completing the music memorization task; and (3) to determine whether ensemble affiliation yielded any performance advantages among the three presentation conditions. Three folk melodies were selected for memorization under the three encoding conditions. Participants ( N = 81) had 75 s to commit each melody to memory while studying silently, singing, or playing on a keyboard. Participants then notated the three melodies using conventional staff notation. A two-way analysis of variance (ANOVA) with repeated measures on one factor revealed significant differences based on participants’ ensemble affiliation. A Tukey’s honest significant difference (HSD) post hoc test revealed the jazz group had higher accuracy scores than the band group. No significant differences were found based on encoding conditions, and no significant interactions were found between the encoding conditions and ensemble groups. The experiment is framed by questions related to memory, reading, and differing notions of literacy.


2020 ◽  
Author(s):  
Xue Jiang ◽  
Zhiwei Cao ◽  
Yang Yao ◽  
Zhihe Zhao ◽  
Wen Liao

Abstract Background: The maxillary anterior teeth play a crucial role in smile aesthetics. Previous studies regarding the importance of maxillary lateral incisors for smile aesthetics concentrated on their size, incisor edge level, and inclination, etc. However, the aesthetic effect of lateral incisor movement in the spatial position has not been studied yet. Therefore, the purpose of this study was to explore the influence of the labiolingual position of maxillary lateral incisors on the aesthetic perception of smiles by orthodontists and laypersons, as well as analyze differences in this perception between male and female raters.Methods: A three-dimensional (3D) dental model was generated from the photograph of a man’s smile using iOrtho7.0 software (Time Angel, Wuxi, China). Based on this model, seven images were generated with different labiolingual positions of the maxillary lateral incisors in 0.5 mm increments (+ indicating labial translation, and - indicating lingual translation). The images were evaluated by 86 orthodontists and 161 laypersons using a visual analog scale, with lower scores indicating less attractiveness. Data were analyzed using Student’s t test and one-way analysis of variance with post hoc test.Results: There was no significant difference in smile ratings by males and females. Orthodontists assigned lower scores to all images than laypersons. The smile at +1.5 mm was considered the least attractive by orthodontists, while smiles at +1.5 mm and -1.5 mm were regarded as the least attractive by laypersons. The smile at 0 mm was evaluated as the most attractive by all raters. Laypersons gave different scores to smiles at 0 or -0.5 mm, but orthodontists did not.Conclusions: The labiolingual position of maxillary lateral incisors does affect the perception of smile aesthetics. Orthodontists may rate smile aesthetics more critically than laypersons. Therefore, communication and discussion between orthodontists and patients is needed to achieve better therapeutic and aesthetic outcomes.


2021 ◽  
Author(s):  
Fahimeh Rezazadeh ◽  
Negin Esnaashari ◽  
Azita Azad ◽  
Sara Emad

Abstract Background: The aim of this study was to investigate the effect of Botulinum toxin-A (BTX-A) injection in lateral pterygoid (LP) muscle and analyze the efficacy of this treatment modality in reducing Temporomandibular disorder (TMD) symptoms. TMD is the main cause of nondental pain in the orofacial area. The most common symptoms of temporomandibular disorder are joints pain and sound and limitation of jaw function. Botulinum toxin (BTX) injection in LP temporarily paralysesis the muscle. BTX injection is considered as a potential treatment for TMD, due to its pain relieving characteristic and its ability to reduce muscle activity. However, these evidences are mostly case series and more studies are required to prove its efficacy. Methods: Thirty-eight patients (19 women and 19 men, mean age: 26.53 years) with painful unilateral temporomandibular joint click and LP muscle tenderness entered the study. They were divided into two groups; one received extraoral Botax injection in LP muscle, and the other was injected by placebo. Pain severity, jaw’s range of movement, click severity and Helkimo-Index, were taken recorded at first and also in follow upin first visit and in one week, one month and three months after intervention. Data were analyzed using Repeated measures ANOVA and t-test.Results: The result showed that click severity was not significantly different between BTX and placebo groups (p=0.07). Pain and Helkimo index were decreased significantly in BTX group (p=0.00 and P=0.006 respectively); however, there was no significant difference when compared between the two groups (P=0.22 and p=1 respectively). There was a significant difference in lateral movements between the groups (p=0.00) but not in protrusion movement (p=0.095).Conclusions: It can be concluded that although some studies state that BTX injection can make the click sound disappear, in this study we did not find a significant difference between two groups. Furthermore, our results showed that click and pain severity were decreased, but the difference was not statistically significant. Therefore, further studies with more dosage of BTX and higher participants seem to be necessary.Trial registration: The local Ethics Committee of Shiraz University of Medical Science approved this research under Ethics code: IR.SUMS.REC. 2018/10/01 and IRCT number: IRCT20130521013406N3.


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