Power Arm Research Articles

Traditional strength training with low row kinesis exercise improving muscle strength and power arm in male students

This study aims to prove the effect of traditional strength training with low row kinesis exercise on increasing muscle strength and arm power in male students. This study uses a pre-experimental method with one group pretest posttest design. A total of 10 adolescent males, aged 20-21 years, and without a history of heart disease were involved in the study and given a traditional strength training intervention with kinesis low row for 6 weeks then muscle strength and power arm measurements were carried out between before and after the intervention. Statistical analysis uses paired sample t-test with a significant level of 5%. The results showed a significant increase in muscle strength between before and after the intervention (21.30±5.91 to 32.65±9.38 kg, p=0.005) and has a large effect size with a Cohen's d value of 1.449. We also observed an increase in power arm between before and after the intervention (178.46±31.84 to 236.96±49.65 kg, p=0.019) and has a large effect size with a Cohen's d value of 1.403. These findings prove that the traditional strength training with low row kinesis exercise intervention for 6 weeks is effective in increasing muscle strength and arm power in male students.

Numerical Simulation of Maxillary Anterior Teeth Retraction Utilizing Power Arms in Lingual Orthodontic Technique.

It was the scope of this study to explore the biomechanical implications of retraction force application point modifications in lingual orthodontics, aiming to mitigate the bowing effect and enhance anchorage stability in the anterior teeth. Using the FE method on an idealized maxillary model, en masse retraction was simulated using a modified lingual fixed appliance including edgewise lingual brackets, a 0.017″ × 0.025″ mushroom-shaped archwire, and power arms between lateral incisors and canines, with a transpalatal arch (TPA) connecting the first molars. Applying bilateral retraction forces of 1.5 N at twelve positions, initial tooth displacements during space closure were evaluated. Shifting power arms gingivally did not effectively counteract palatal tipping of incisors but reduced posterior and palatal tipping of canines with a power arm length of 11.3 mm preventing posterior tipping. Apically displacing the TPA retraction force increased mesiobuccal rotation while preventing mesial molar tipping for retraction forces applied 12.6 mm from the archwire. Apically shifting retraction forces can mitigate vertical bowing effects in lingual orthodontics, yet it also highlights the challenges in maintaining torque in the anterior teeth. Further research and clinical validation are essential in order to confirm these results, emphasizing the complexity and need for advanced biomechanical strategies in personalized lingual orthodontic treatments.

Research on Output Characteristics of a Non-Contact Piezoelectric Actuator’s Micro-Displacement Amplifying Mechanism

A non-contact piezoelectric actuator is proposed. The non-contact power transfer between stator and rotor is realized by pneumatic transmission, characterized by fast response, long life, compact structure, and easy miniaturization and control. The structure of the non-contact piezoelectric actuator is designed and its working principle is elucidated. The equation of the relationship between the output displacements of the non-contact piezoelectric actuator’s micro-displacement amplifying mechanism and the input displacements of piezoelectric stack is deduced, and the simulation analysis method of output displacement of the micro-displacement amplifying mechanism is established. Using the equation and the simulation analysis, the output characteristics of micro-displacement amplifying mechanism for the non-contact piezoelectric actuator and their changes along with the system parameters are investigated. The detailed process of optimal design of the micro-displacement amplifying mechanism is given by means of mathematical statistics. The prototype is made and the performance test is carried out. The correctness of the theoretical calculation and simulation analysis is verified by comparing the experimental values with the theoretical and simulated values of the output displacement of the micro-displacement amplifying mechanism. The results show that the initial angle of bridge structure I has an obvious effect on the output characteristics of the micro-displacement amplifying mechanism in the range of 5°–15°. When the lever’s rod length is 13 mm–15 mm, the bridge structure II’s rod length is 6 mm–7 mm, and the power arm length of bridge structure I’s driving lever is 5 mm–7 mm, the bridge structure II’s rod horizontal projection length is 5 mm–6 mm and the output displacement of the micro-displacement amplifying mechanism is larger. Through the optimal design, it is obtained that the bridge structure I’s initial angle is 8°, the lever’s rod length is 15 mm, the bridge structure II’s rod length is 7 mm, and the power arm length of bridge structure I driving lever is 5 mm, the bridge structure II’s rod horizontal projection length is 6 mm, and the simulated output displacement of the micro-displacement amplifying mechanism is 0.1415 mm. The prototype test reveals that as the input excitation displacement decreases, the error increases, while as the input excitation displacement increases, the error decreases. Specifically, when the input excitation displacement is 0.005 mm, the measured output displacement of the micro-displacement amplifying mechanism is 0.1239 mm, resulting in a 19.8% deviation from the theoretical value and a 12.44% deviation from the simulated value. The research work in this paper enriches the research achievements of non-contact piezoelectric actuators, and also provides a reference for designing small structure and large travel micro-displacement amplifying mechanisms of this type of actuator.

Finite element analysis of the effects of different archwire forms and power arm positions on maxillary incisors in en masse retraction using fixed lingual orthodontic appliances.

This study aimed to investigate the effects of archwire form and power arm positions on maxillary incisors during lingual en masse retraction supported by miniscrew implants, using the finite element analysis method. Sliding mechanics for lingual en masse retraction were simulated using the finite element method. Power arms were placed mesial and distal to the maxillary canine with straight and mushroom-shaped archwires. Miniscrews provided absolute anchorage for retraction force. When power arms were positioned mesial to the canine teeth, an increase in the intercanine distance was observed, while a decrease was noted when the power arms were distal to the canine tooth. Lateral incisors exhibited a greater torque loss, particularly when the power arm was mesial to the canine tooth. In the central incisors, the mushroom archwire resulted in intrusion, while the straight archwire showed an extrusion tendency. Movements in groups using the straight archwire were less controlled compared to those in groups using the mushroom archwire. The archwire form and the position of the power arm affected the torque loss and vertical position of incisors during lingual en masse retraction supported by miniscrew implants. The most controlled movement was achieved with the combination of a power arm positioned distal to the canine tooth and a mushroom archform.

Relationship between Arm Length, Power Arm Muscles and Power Lemb Muscles on Butterfly Style Swimming Achievement

This study aims to determine the relationship between arm length, arm muscle power and leg muscle power on butterfly swimming performance. This research uses a survey method. Data collection techniques use tests and measurements. The population in this study were swimming athletes aged 12 to 13 years in the Special Region of Yogyakarta Province. The research used was population research with a total of 27 athletes. The main instruments used are the arm length test, arm muscle power test, leg muscle power test and 25 meter butterfly swimming test. The data analysis used is the normality test, linearity test, correlation test and multiple regression analysis test with a significance level of 5%. The results showed that the relationship between arm length and butterfly swimming performance was 0.617, the relationship between arm muscle power and butterfly swimming performance was 0.460, the relationship between leg muscle power and butterfly swimming performance was 0.838 and the relationship between arm length, arm muscle power and leg muscle power on butterfly swimming performance is 0.897. The correlation between arm length is greater than arm muscle power because each athlete's butterfly swimming technique is not the same (how much the elbow bends when the arm is pulled).

Efficiency of friction versus frictionless mechanics for correcting bimaxillary dentoalveolar protrusion in dizygotic twins – A case report

The purpose of this case presentation is to determine the efficiency of two treatment mechanics in correcting clinically comparable malocclusion in dizygotic twins. The case report describes the orthodontic management of 19-year-old non-identical twins diagnosed with bimaxillary dentoalveolar protrusion on a Class I skeletal base with severe crowding using two different treatment mechanics. The first patient was treated with frictionless mechanics by making use of Kalra simultaneous intrusion and retraction arch for space closure, whereas the friction mechanics accomplished the task in the second patient with mini-implant (Titanium mini-implant, FavAnchor™ SAS, Favorite supplies, Thane west, Maharashtra, India) assisted power arm (Power hook, Azdent Orthodontics, Zhengzhou, China) retraction. It evaluated the overall treatment duration, anterior torque control, and level of comfort for the patients with the two mechanics. The post-treatment results in both cases exhibited remarkable change in inclination of upper anterior teeth which were established through cephalometric findings. Moreover, the anterior torque control was comparatively superior with loop mechanics over mini-implant assisted sliding mechanics. Both the treatment mechanics effectively and efficiently corrected the malocclusion with considerable impact on soft-tissue profile.

Evaluating the Injection of Platelet-Rich Plasma on Second Lower Molars Protraction: A Randomized Controlled Clinical Trial.

Background The use of platelet-rich plasma (PRP) in dentistry was entered several decades ago, yet its clinical use in orthodontics still requires further investigation. The aim of this study was to evaluate the possible effects of local injection of PRP on the rate and typeof mandibular second molar protractionmovement compared with the comparator (no PRP) group. Material and methods Eighteen patients aged between 17 and 25 years were randomly allocated in a split-mouth study design to receive PRP injections on one sideimmediately before the start of molar protraction (PRP group), while the other side received only saline solution (comparator group). Eligibility criteria included bilaterally extracted mandibular first molars casesand indicated mandibular second molars protraction. The primary outcome of the study consisted of measuring the rate of molar protraction from the beginning of protraction (T0) to the end of the seventh month (TF), using a digital gauge. The secondary outcome included measuring the typeof second molar protraction movement between T0 and TFby lateral cephalometric images. Randomization of the intervention side was performed by picking out opaque sealed envelopes. The blinding of the principal investigator was impossible but blinding of the patient was achieved by injection of saline. Analyses were done using paired samples T-test to compare the changes in all variables between T0 and TF. The level of significance was taken at a P-value < 0.05. Results No significant difference was detected between the PRP and comparator groups in the rate of second lower molar protraction during seven months (0.56±0.07 mm per month in the comparator group, whereas, was 0.6±0.11 mm per month in the PRP group). Molar protraction parameters in both groups showed second lower molars moving by controlled tipping closer to bodily movement (Root Movement:Crown Movement≈0.8). Conclusions Platelet-rich plasma (PRP) is ineffective in accelerating the rate of orthodontic tooth movement (OTM) during molar protraction, and it has no effect on the type of tooth movement. In addition, the mechanics that we used (6 mm power arm in combination with miniscrews) are effective in mandibular second molar protraction by controlled tipping closer to bodily movement.

Biomechanical effect of dual-dimensional archwire on controlled movement of anterior teeth compared with rectangular archwire: A finite element study

This study aimed to determine and compare the effectiveness of the use of the dual-dimensional archwire and conventional rectangular archwire on tooth movement patterns when combined with various lengths of power arms. Displacements of the maxillary central incisor and the deformation of the wire section were calculated when applying retraction forces from different lengths of power arms using the finite element method. Torque control of the incisor could be carried out more effectively when using the dual-dimensional archwire combined with long power arms than with the rectangular archwire. The use of the dual-dimensional archwire produced bodily movement of the central incisor at height levels of the power arm between 8 and 10 mm and lingual root tipping at the level of 10 mm. The use of the dual-dimensional archwire provided better-controlled movement of the incisor, including bodily movement or root movement, than the rectangular archwire.

Biomechanical analysis of total arch maxillary distalization using infrazygomatic crest miniscrews: a finite element analysis study

AimTo evaluate the maxillary incisors and canine’s immediate movement tendency using three different power arms (PA) height levels during total arch maxillary distalization supported on infrazygomatic crest (IZC) miniscrews according to finite element analysis (FEA).MethodsThree finite element models of the maxilla were developed based on CBCT imaging of a teenage male patient presenting a Class II Division 1 malocclusion in the early permanent dentition. Maxillary complex, periodontium, orthodontic accessories, IZC miniscrews and an orthodontic wire were digitally created. The PAs were placed between canines and lateral incisors and projected at 4, 7, and 10 mm height distances. After that, distalization forces were simulated between PA and IZC miniscrews.ResultsThe anterior teeth deformation produced in the FEA models was assessed according to a Von Mises equivalent. The stress was measured, revealing tendencies of initial maxillary teeth movement. No differences were found between the right and left sides. However, there was a significant difference among models in the under-stress areas, especially the apical and cervical root areas of the maxillary anterior teeth. More significant extrusion and lingual tipping of incisors were observed with the 4 mm power arm compared to the 7 mm and 10 mm ones. The 10 mm power arm did not show any tendency for extrusion of maxillary central incisors but a tendency for buccal tipping and intrusion of lateral incisors.ConclusionThe maxillary incisors and canines have different immediate movement tendencies according to the height of the anterior point of the en-masse distalization force application. Based on the PA height increase, a change from lingual to buccal tipping and less extrusion tendency was observed for the incisors, while the lingual tipping and extrusion trend for canines increased.

Effects of aligner activation and power arm length and material on canine displacement and periodontal ligament stress: a finite element analysis

BackgroundThis study aimed to assess the impact of aligner activation and power arm length and material on canine and aligner displacement, von Mises stress in the power arm, and principal stress in the periodontal ligament (PDL) during canine tooth distalization using finite element analysis (FEA). The effects of aligner activation and power arm length were primary outcomes, while the effect of the power arm material was a secondary outcome.MethodsAligner activation (0.1 mm or 0.2 mm) was applied without using a power arm in two models. The effects of aligner activation, power arm length (12, 13, or 14 mm) and power arm material (stainless steel [SS] or fiber-reinforced composite [FRC]) on canine distalization were investigated in 12 models by evaluating displacement and stress via ALTAIR OptiStruct analysis.ResultsGreater canine displacement was observed in all models with 0.2 mm than 0.1 mm of aligner activation. When models with the same aligner activation were compared, reduced mesiodistal tipping, increased palatal tipping, and increased extrusion of the canine cusp were observed with increasing power arm length. Moreover, the von Mises stress increased as the power arm length increased. Increasing the aligner activation and power arm length increased the maximum principal stress in the PDL. Power arms of the same length in both materials showed the same results in terms of canine displacement, clear aligner displacement, and maximum principal stress in the PDL. However, under conditions of equal length and aligner activation, the von Mises stress of the SS power arm was higher than that of the FRC power arm.ConclusionUsing a power arm in canine distalization reduced mesiodistal tipping but increased palatal tipping and extrusion of the canine cusp. Aligner activation and additional force increased tooth movement and principal stress in the canine PDL. FRC power arms exhibited less von Mises stress than SS power arms.

Effect of power arm length combined with additional anterior torque on the axial orientation of the maxillary incisors during en-masse retraction: A finite element analysis

This study aimed to clarify the effect of power arm length combined with additional torque incorporated into the archwire on the controlled movement of the anterior teeth using the finite element method. An adult patient requiring medium anchorage after extraction of the maxillary first premolars was selected for this study. The power arms were placed between the lateral incisor and the canine at 3 levels: 3 mm, 6 mm, and 9 mm. A 150 g of retraction force was applied from each height of the anterior hook to the first molar tube, with 0°, 5°, and 10° of applied lingual root torque on the incisors. A 3-mm hook with 10° of applied torque, a 6-mm hook with 5° of applied torque, or a 9-mm hook with no extra torque constituted the best combinations targeted at controlling the inclination of incisors during retraction. Extrusion and distal tipping of the canine were observed. Moreover, mesial tipping and mesiopalatal rotation of the molar were unavoidable. Finally, intercanine and intermolar widths were decreased. Adding extra torque on the incisors or using high torque brackets is recommended for patients with maxillary first premolar extraction.

Overview of Ability Levels of Physical Conditions of Athletic Athletes Center for Student Training Education (PPLP)

This study aims to determine the level of the physical condition of PPLP West Sumatra athletes which includes: endurance, strength, speed, flexibility, endurance strength, explosive power and leg muscle explosive power arm muscles. this research is descriptive. The population in this study, PPLP West Sumatra athletic athletes which amounted to 14 people consisting of 9 athletes of male and 5 female athletes. Data were analyzed by percentage formula P = (F / N) x 100%. The results were obtained: 1. The level of ability of endurance athletes possessed by sons and daughters are being categorized, 2. The level of ability of the strength of male and female athletes including one less category, 3. The level of speed capabilities possessed by males and female athletes are categorized 4. The degree of flexibility that is owned by sons and daughters athletes get good category, 5. The degree of endurance strength of the male athlete category and female athletes are less category, 6. The degree of leg muscle explosive power possessed male athlete including in the medium category and female athlete, including at least once a category, 7. The degree of arm muscle explosive power possessed male athlete gain medium category and daughter get one less category.

Lever-inspired triboelectric respiration sensor for respiratory behavioral assessment and exhaled hydrogen sulfide detection

Enhancing the flow sensitivity of the triboelectric respiration sensors (TRSs) is crucial in detecting shallow oral/nasal breath signal. The modulation of contact-separate distances between dielectrics is a simple and convenient tactic to enhance the output sensitivity of TRSs compared with the complex composite materials and microstructure design of the triboelectric dielectrics. Herein, a lever-inspired TRS with adjustable contact-separate distances between arms was designed for simultaneous respiratory behavioral assessment and exhaled hydrogen sulfide (H2S) detection. Results show that the TRS with the optimal length ratio of power arm to resistance arm (1:2) possesses excellent respiration sensing behaviors in measuring flow rate (0.5–8 L/min) and frequency (0.25–1 Hz), enabling the flow sensitivity under oral/nasal respiration. Meanwhile, an in-situ self-assembled Fe2+ doped polypyrrole (FPPy) sensing film was rationally selected as one of the back electrodes of triboelectric layers owing to the selective reaction between ferrous ions (Fe2+) and H2S. Under the optimal synthesis condition of FPPy film, the prepared TRS exhibits good H2S sensing performances, including a high response of 25.21% (10 ppm), good sensing repeatability (±0.46%), and low detection limit (1 ppm). Finally, a sensing mechanism on account of the impedance variations is proposed and verified based on the composition changes of the sensing materials unveiled by multiple analytical methods. This work proposes an effective way for building a flow-sensitive respiration monitoring device, and provides new insights into the impedance-induced sensing mechanism via establishing a linkage between interfacial gas chemisorption and output signals.

Influence of Different Mouth Rinsing Agents on Friction During Sliding Mechanics Between Orthodontic Metal Brackets and Stainless Steel Archwire: A Comparative In Vitro Study.

Aim and objectives The aim of this in-vitro study is to evaluate and compare the effect of various mouth rinsing agents on frictional resistance through sliding mechanics among orthodontic metal brackets and stainless steel (SS) archwire. Materials and methods Each group comprised 15 samples of maxillary first premolar pre-adjusted edgewise SS movable, un-bonded brackets (Koden Inc., United States) which were welded with a power arm, where 100 gof the load was suspended. Brackets were ligated with elastic modules (Koden Inc., United States) onto the perspex sheet along with 0.019" x 0.025" SS archwire (Classic Orthodontics, United States) and were suspended from the upper component of the Instron machine. The coefficient of friction was tested in dry conditions (control), artificial saliva (AS) (Wet Mouth, ICPA Health Product Ltd., India), 0.2% chlorhexidine gluconate (CHG) mouthwash (Hexidine, ICPA Health Product Ltd., India), 0.05% sodium fluoride (NaF) mouthwash (ACT Anti-Cavity Fluoride Mouthwash, Sanofi Company, United States), charcoal (CC) mouthwash (Hello Activated Charcoal Extra Freshening Mouthwash, Hello Products LLC, United States) and ozone-infused oil-pulling solution with coconut oil (O3) (O3Essentials, Health Ranger Store, United States). In order to calculate the coefficient of friction, 50 L was addedto the test sample while moving at a 5 mm/min crosshead speed. The groups were compared using the one-way analysis of variance (ANOVA), and Tukey's post hoc analysis was performed for multiple pairwise comparisons. Results The coefficient of friction with the highest mean values was observed with the control group (2.01), followed by AS (1.79), and the least with O3(1.15). Statistically significant differences were observed with almost all groups of mouth rinsing agents, but NaF is significant with CHG and CC. However, CHG did not have any significant difference from CC. Conclusions Lower coefficient of frictional values were observed with the ozone-infused oil-pulling solution with coconut oil during sliding mechanics between metal brackets and stainless steel archwire. Almost all the mouth rinsing agents showed a significantly different coefficient of friction value.

The technical assessment of the level of innovative traction transmission of railway vehicle

The article deals with the development of an innovative model of traction transmissions of railway vehicles with a higher technical level, which allows to eliminate the existing shortcomings of the mechanical system, simplify the repair processes and reduce the cost, and evaluate its technical level. By reducing the overall dimensions and weight of the mechanical system, increasing reliability due to equal distribution of the load and shortening the power arm, as well as reducing the number of structural elements, increasing the useful work coefficient due to the reduction of the mass of double sliding pads and rotating parts, saving electricity and thereby improving the technical level of rail transport. Traction transmissions consisting of an innovative reducer are offered that ensure the increase.&#x0D; The technical level of the proposed dart transmission is determined based on three compatibility parameters with a creative approach. Compatibility parameters are determined according to the minimum value of the geometric dimensions characterizing the mass of the mechanical system, the maximum value of the useful work coefficient characterizing economic efficiency, as well as the maximum values of the degree of reliability characterizing safety. The technical level of the proposed project transmitter is determined and compared with existing buildings, its technical and economic advantages are highlighted. As a result of the application of the proposed innovative reducers in the traction drives of railway vehicles, the basis is created for reducing the cost and maintenance costs of traction vehicles, increasing the level of traffic safety, as well as improving the traction and braking characteristics

Displacement Pattern, Stress Distribution, and Archwire Play Dimensions during En-masse Retraction of Anterior Teeth using Sliding Mechanics: A FEM Study.

This finite element study was undertaken to evaluate the pattern of stress distribution around the implant and anterior teeth during en-masse retraction in the premolar extraction case. Displacement of the teeth and play of wire in the bracket slot were also evaluated to determine the most favorable height of the power arm attached to the arch-wire. A three-dimensional (3D) finite element model of the maxilla was constructed using computed tomography (CT) scan. A total of 12 models were fabricated with different heights of power arms placed distal to the canine. A retraction force of 1.5 N was applied from the implant placed between the roots of the second premolar and first molar, and the response was predicted using Analysis of Systems (ANSYS) software. When power-arm height was near the center of resistance of the anterior segment, stability in the stress distribution around the implant site and anterior teeth was observed. Displacement of the teeth varied along the three planes of space with the change in power-arm height. For en-masse retraction, power-arm height should be kept at a level of the center of resistance. Play in the bracket slot and the archwire show a negative role in the bodily movement of anterior teeth. For efficient en-masse retraction of anterior teeth, it is imperative to study the most effective site of application of force. Therefore, our study recommends certain key points to keep in mind during the attachment of the power arm and engaging wire in the bracket slot, which could benefit the orthodontist immensely. Singh H, Khanna M, Walia C, et al. Displacement Pattern, Stress Distribution, and Archwire Play Dimensions during En-masse Retraction of Anterior Teeth using Sliding Mechanics: A FEM Study. Int J Clin Pediatr Dent 2022;15(6):739-744.

Perancangan Alat Pencetak Brown Sugar Cube

Palm is a type of palm whose potential for high economic value and can thrive in Indonesia. Nagari Andaleh Baruh Bukik is an area in Tanah Datar District that is a center of palm crop production and has the potential to be developed by its economy. Seeing a promising market, the idea was born to process ant sugar into brown sugar cubes by making a brown sugar cube printer. The manufacture of brown sugar cubes using the manual press method with a pressing system utilizes the principle of the 2nd type of leverage, where the load point is between the power point and the fulcrum. This pressing system works if the lever is pulled by the operator according to the specified depth limit, to restore the position of the lever to its original position is to take advantage of the spring force. It takes about 392 N to press the mold. By doing the calculation so that a mechanical profit is obtained 3 times, the total force required to press is 130.6 N. The safety factor equation is 69.76 N/mm2 ≤ 200 MPa with the largest curved moment being 130.87 N/mm2, so this tool is safe and will not be bent. Power arm length: 34.5 cm, weight arm length: 11.5 cm. Designing components and assembling brown sugar cube printers using the SolidWork application.

Evaluation of Stress Distribution of Maxillary Anterior Segment during en Masse Retraction Using Posterior Mini Screw: A Finite Element Study

The current study aimed to perceive and estimate the distribution of stress generated by the forces on the maxillary anterior teeth during orthodontic retraction using the bilateral mini screw implant. Finite element models were generated from the three-dimensional (3D) reconstruction of the maxillary arch via cone–beam computed tomography (CBCT). These models imitate the retraction of maxillary anterior teeth with the mini screw placed as the skeletal anchorage. The titanium mini screw of 1.3 mm × 8 mm dimension was placed at a height of 9 mm between the first molar and second premolar on both sides of the maxilla. A nickel titanium (NiTi) coil spring of 9 mm length was attached from the mini screw implant to the power arm which generated a force of 250 gm/side. Two different power arms were placed between the lateral incisor and canine at a height of 4 mm (group 1) and 8 mm (group 2), respectively. There were no significant differences observed when the stress values were compared to the left side and the right side in group 1 with a power arm of 4 mm. In group 2, the stresses around the lateral incisors were found to be on the higher side when compared with the central incisors and canines. The length of the power arm shows no significant difference in stress distribution pattern on the left and right sides except for stresses moving from the canine region to the lateral incisor region with the increase in power arm height.

Relationship of Power, Waist Muscle Flexibility, and Power Muscle Legs Against Smash Volleyball For FIK UNM Makassar Students

Power Leg Muscle Power volleyball for FIK UNM Makassar students. The sample used in this study were FIK UNM Makassar students who took volleyball courses. Data analysis techniques used to test the hypothesis are normality test, linearity test, and correlation test. From the results of the first hypothesis correlation test, a significance value of 0.046 &lt; 0.05 was obtained, so there was a significant relationship between power arm muscle smash. The results of the second hypothesis test have a significance value of 0.037 &lt; 0.05, so there is a significant relationship between Waist Muscle Flexibility and Smash. The results of the third hypothesis test have a significance value of 0.032 &lt; 0.05, so there is a significant relationship between Waist Muscle Flexibility and Smash. Based on the multiple correlation test in the summary model table, it is known that the magnitude of the relationship between arm muscle power, waist muscle flexibility and leg muscle power (simultaneously) on the smash results calculated by the correlation coefficient is 0.452, this indicates a moderate effect. Meanwhile, the simultaneous contribution or contribution of the arm muscle power variable with the flexibility of the waist muscles is 20.4% while 79.1% is determined by other variables.

The Influence of Heights of Power Arm for Controlled Anterior Teeth Movement in Sliding Mechanics: A 3D FEM Study

Introduction: The effectiveness of orthodontic treatment depends on precise control of the anterior teeth during retraction in sliding mechanics. That is why researchers were interested in finding the appropriate loading conditions for sliding mechanics to govern anterior teeth's movement, such as the height of retraction force application and its location on the arch wire.Methods: A FEM study was conducted to evaluate the type of movement of anterior teeth during en-masse retraction by applying 200 gms of force to each side of the maxillary arch with power arms set at various levels (4 mm, 6 mm, 8 mm) mesial to canine from mini-screw placed at a height of 8 mm between maxillary first molar and second premolar. A 3D model (FEM) of the maxillary arch was constructed to study the amount of labio-lingual tipping and bodily displacement of maxillary central incisor achieved.Results: When a 200-gm power was applied to the power arm, controlled lingual crown tipping was seen at the levels of 4 mm and 6 mm, in contrast to the level of 8 mm, where bodily displacement occurred, according to this evaluation. Conclusion: In sliding mechanics, the height of the power arm plays an important role in obtaining controlled lingual crown tipping or bodily displacement during retraction of anterior teeth.