Fatemeh Gorjizadeh; Maryam Javaheri Mahd; Abdo Rahim Maktabi
Abstract
Background: Prediction of the mesio-distal width of the unerupted premolars and canine is an important point to the practitioner.
Objectives: The main goal of this study was to find the relationship of the teeth size to be used when needed in treatments planning. Materials and Methods: 200 plaster casts ...
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Background: Prediction of the mesio-distal width of the unerupted premolars and canine is an important point to the practitioner.
Objectives: The main goal of this study was to find the relationship of the teeth size to be used when needed in treatments planning. Materials and Methods: 200 plaster casts including 5600 teeth were measured and studies. A caliper with accuracy of 0.1 mm was used for measuring teeth and most teeth were measured twice and the average value was considered as the teeth size. In all cases, the vernier calipers jaws were moved along the teeth longitudinal axis and the biggest width was measured in the contact point area.
Results: Tables of mesiodistal widths of the permanent teeth and some equations were prepared. The measurement difference varied from 0 to 0.04 mm. the average value of difference was 0.016 mm with SD of 0.02 mm. All teeth in male are bigger than those in female and this different is most evident in canine teeth, especially the lower jaw canine teeth.
Conclusions: At the end of this study an equation was found which was used to measure the total value of mesiodistal width of canine and premolar teeth of upper and lower jaws in a simple and exact way.
Jean Marc Retrouvey; Allahyar Geramy
Abstract
Background: Occlusal loads are always present though not widely considered in orthodontic treatments. Applied force systems are analyzed in detail and taught but their interaction with occlusal force is oftentimes ignored. Numeric evaluation of this combination by finite element method is the main goal ...
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Background: Occlusal loads are always present though not widely considered in orthodontic treatments. Applied force systems are analyzed in detail and taught but their interaction with occlusal force is oftentimes ignored. Numeric evaluation of this combination by finite element method is the main goal of this research.
Objectives: The present study has implemented FEA to investigate the effect of orthodontic force application on the tooth-periodontium-alveolar bone system. Materials and Methods: A 3D model of a lower premolar was designed. The model contained cortical and spongy bone, PDL, and tooth. A 1.73 N force decomposed to 1 N in each plane axis was applied as a random levelling and aligning force to assess the von Mises stress produced at the mesial aspect of the PDL from cervical down to the apical area. At the second phase a 200-Newton intruding force vector was applied simulating the occlusal force. The effects of the combination force system were evaluated in the same area of the PDL. Results: The maximum finding of von Mises for both stages were in found in the cervical area. This was almost 0.267 MPa for the first stage and 2.27 MPa for the second stage.
Conclusions: Our findings show that the co-existence of heavy occlusal forces due to clenching or bruxism in our tooth-periodontium-orthodontic force system has a significant influence on the magnitude and location of the high stress areas.
Hasan Salehi; Sepide Arab
Abstract
Background: Alignment of the teeth as the first stage of comprehensive orthodontic treatment has widely been addressed. Several methods such as using super elastic arch wires, multi-strand wires and incorporation of various loops into the round stainless steel wires have been suggested in this stage.
Objectives: ...
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Background: Alignment of the teeth as the first stage of comprehensive orthodontic treatment has widely been addressed. Several methods such as using super elastic arch wires, multi-strand wires and incorporation of various loops into the round stainless steel wires have been suggested in this stage.
Objectives: The aim of this study was to investigate and compare the horizontal forces produced by six various loop designs in different amounts of activation using the finite element method. Materials and Methods: The Finite Element Model (FEM) was used to design and compare the horizontal forces of round 0.014 inches stainless steel vertical open loop, vertical closed loop, vertical helical open loop, vertical helical closed loop, plain vertical loop and the squash loop. The forces were measured at 0.1, 0.4, 0.8 and 1mm activations. Results: For all activations, vertical open loop had the highest horizontal force; while vertical helical closed loop showed the lowest force.
Conclusions: The design of vertical loops influences the horizontal force in all activations, immensely.
Mohammad Reza Jamalpour; Mohammad Moslem Imani; Atefe Saffar Shahroudi; Sina Oladzadeh
Abstract
Background: Facial trauma is a common sport-related injury and risk of this injury in contact sports is greater than non-contact sports. Facial trauma has been suggested as a possible etiologic factor of temporomandibular disorder (TMD).
Objectives: The purpose of this study was to investigate the frequency ...
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Background: Facial trauma is a common sport-related injury and risk of this injury in contact sports is greater than non-contact sports. Facial trauma has been suggested as a possible etiologic factor of temporomandibular disorder (TMD).
Objectives: The purpose of this study was to investigate the frequency of TMD and its clinical manifestation in boxers of Islamic Republic of Iran national team. Materials and Methods: In this study, thirty-two male players with average age of 23.75 ± 2.21 who were playing boxing more than 6 years were evaluated regarding TMD. After taking the history, a clinical examination was performed for each athlete. The presence of at least a sign or symptom was considered as TMD diagnosis. Data were collected and presented as descriptive findings. Results: Of 32 boxers, 28.1% (9 cases) had TMD and 71.9% (23 cases) were healthy. The most common symptom was ante-auricular pain (25%) followed by neck pain (21.87%) right ante-auricular tenderness (9.37%) muscle tenderness (9.37%), neck tenderness (9.37%) and headache (3.12%). The uppermost sign was right joint click (25%) followed by left joint click (12.5%) and jaw deviation during mouth opening (12.5%).average age of (25 ± 2 years) and boxing record (10.44 ± 2.29 years) of athletes with TMD were higher than average age of (23.26 ± 2.4 years) and boxing record (7.26 ± 1.76 years) of athletes without TMD.
Conclusions: This study showed that the prevalence of various sign and symptoms of TMD is relatively high in boxers which could result from boxing-related facial trauma.
Mohsen Shirazi; Homa Farhadifard; Meisam Moradi; Hamid Golshahi
Abstract
Introduction: Cleft lip and palate (CLP) is the most common congenital facial anomaly. Its incidence varies according to epidemiologic studies but is usually between 1 and 1.82 for each 1000 births. The etiology of this malformation is complex and includes both genetic and environmental factors.
Case ...
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Introduction: Cleft lip and palate (CLP) is the most common congenital facial anomaly. Its incidence varies according to epidemiologic studies but is usually between 1 and 1.82 for each 1000 births. The etiology of this malformation is complex and includes both genetic and environmental factors.
Case Presentation: In this article a 13-year-old girl with CLP is presented. She was treated with expansion of maxillary arch form, bone grafting, pre surgical orthodontics, orthognathic surgery and minor esthetic surgical procedure.
Conclusions: Satisfactory results regarding functional occlusion, dental esthetics, and facial esthetics were achieved in the patient.
Reza Jelodar; Farhad Shafiei; Angela Yalda Rezaei
Abstract
Background: In the oral environment orthodontic wires will be subjected to thermal fluctuations and repeated loading (fatigue).
Objectives: The aim of this study is to evaluate the thermocycling and fatigue effect on the CuNiti wires. Materials and Methods: Samples of CuNiti wires, 0.014 round, were ...
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Background: In the oral environment orthodontic wires will be subjected to thermal fluctuations and repeated loading (fatigue).
Objectives: The aim of this study is to evaluate the thermocycling and fatigue effect on the CuNiti wires. Materials and Methods: Samples of CuNiti wires, 0.014 round, were divided into four groups: 1, Fatigue loading; 2, Fatigue and thermocycling; 3, thermocycling; 4, control. The groups involved in fatigue loading by determined protocol (0.5 mm deflection, 1Hz frequency) also thermocycling performed by this method: bath time (90 seconds), transfer time (15 seconds) and temperature range: 5 - 55C.after these procedure, fatigue and thermocycling effects on the maximum loading force (MLF) and maximum unloading force (MULF) assessed with a 3-point bending test. Results: In this study, the amounts of MLF in group 1 and 2 were significantly different with themselves and control group, but in the control group, the results were not significantly different with thermocycling group. Also the amounts of MLF in the group 3 were not different by the group 1 and 2. For the MULF, the results of group 1 and 2 were significantly different with the control and thermocycling group. Difference between fatigue and control groups for hysteresis loading (difference between MLF and MULF) variable was not significant while other two by two comparisons were significant.
Conclusions: The fatigue loading increased MLF and MULF, but the effect of thermocycling was complicated on the MLF. Thermocycling also did not affect the MULF, but decreased hysteresis loading.
Elahe Soltanmohamadi Borujeni; Homa Farhadifard
Abstract
Context: The use of skeletal anchorage not only changed how far teeth can be moved, but also offered more treatment options to patients and clinicians. So many orthodontists use them in severe malocclusions to save patient from orthognatic surgery and the other invasive treatment plans. So our information ...
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Context: The use of skeletal anchorage not only changed how far teeth can be moved, but also offered more treatment options to patients and clinicians. So many orthodontists use them in severe malocclusions to save patient from orthognatic surgery and the other invasive treatment plans. So our information about them must increase to use them in a right way.
Evidence Acquisition: To know recent findings about miniscrews and their use in orthodontic treatments
Results: In this review article, by focusing on the newest papers published in PubMed (from 2010 - 2015) we want to survey the most common applications of miniscrews in today orthodontics. To ease reading this paper, applications where divided into 7 groups. Almost all of papers used in this article had a common conclusion about safety and effectiveness of miniscrews in treatment of patients.
Conclusions: miniscrews are helpful in increasing treatment options for various malocclusions and they make treatment simpler, shorter and more comfortable for patients and clinicians.
Shabnam Ajami; Hooman Zarif Najafi; Sareh Mahdavi
Abstract
Background: The evaluation of the soft tissue facial profile is essential to achieve facial harmony in orthodontic diagnosis and treatment planning.
Objectives: This study aimed to develop soft tissue angular photogrammetric norms for a sample of Iranian population.
Patients and Methods: Standardized ...
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Background: The evaluation of the soft tissue facial profile is essential to achieve facial harmony in orthodontic diagnosis and treatment planning.
Objectives: This study aimed to develop soft tissue angular photogrammetric norms for a sample of Iranian population.
Patients and Methods: Standardized profile photographic records were taken from 34 men and 37 women. Twelve measurements were analyzed on each photograph by AutoCad software. For statistical evaluation a Student’s t-test was used and the reliability of the method was assessed by using Intra-class Correlation Coefficient (ICC) within a four week interval. Results: Three of the angles showed sexual differences: nasofrontal (G-N-Prn, P = 0.009), nasal (Cm-Sn/N-Prn, P = 0.012) and vertical nasal (N-Prn/Tv, P = 0.029). Other nine angles showed statistically insignificant gender differences (P > 0.05). Two of the angles that suggested gender differences were wider in females: nasofrontal and nasal angle while the third angle was wider in males. Other angles such as nasolabial (Cm-Sn-Ls), mentolabial (Li-Sm-Pg), nasal dorsum (N-Mn-Prn) and angle of the total convexity (G-Prn-Pg) were also found wider in females. The inferior third was larger than the middle third. Mentolabial angle (Li-Sm-Pg), which had the highest standard deviation, showed the greatest variability.
Conclusions: The results showed gender dimorphism in three of the measurements: the nasofrontal, the nasal and the vertical nasal angles. Another significant finding was the large variability for the mentolabial angle. The result of this measurement should be assessed with caution.
