Parham Pedram; Hannane Ghadirian; Sepideh Arab
Abstract
Background: Splinting anterior teeth is a way to fix them after orthodontics treatments. Occlusal trauma from functional or parafunctional forces can cause stress increase and movements of teeth especially while having bone loss.
Methods: Six anterior teeth with different bone levels were designed in ...
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Background: Splinting anterior teeth is a way to fix them after orthodontics treatments. Occlusal trauma from functional or parafunctional forces can cause stress increase and movements of teeth especially while having bone loss.
Methods: Six anterior teeth with different bone levels were designed in SolidWorks (2010), the models were then transferred to ANSYS Workbench 12.1. The models were loaded with 187 N force on the incisal edges of two incisors. Results: Stress on canine was 0.45 MPa in normal bone height and increased to 0.60 MPa in five millimeters of anterior teeth bone loss. Labial displacement was less in normal alveolar bone height while it was increased in all those teeth with five millimeter of bone loss.
Conclusions: Splinting distribute the forces between teeth and the stress production on canine increase while it splinted with low level bone incisors. Anterior teeth also showed tipping movements in reply to increased forces.
Zahra Dalili Kajan; Ali Khalighi Sigaroudi; Negar Khosravifard; Nahid Farsam
Abstract
Background: The mandibular foramen has often been considered as the most reliable reference point for several anesthetic and surgical procedures in the maxillofacial region. This study evaluated the position of the mandibular foramen in different skeletal classes.
Methods: A total of 90 panoramic and ...
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Background: The mandibular foramen has often been considered as the most reliable reference point for several anesthetic and surgical procedures in the maxillofacial region. This study evaluated the position of the mandibular foramen in different skeletal classes.
Methods: A total of 90 panoramic and lateral cephalometric images belonging to class I (n = 30), class II (n = 30), and class III (n = 30) patients were used for this study. The position of the mandibular foramen in relation to the anterior and posterior borders of the mandibular ramus, inferior border of the mandible, sigmoid notch and occlusal plane was determined in each panoramic radiograph. Results: The position of the mandibular foramen relative to the occlusal plane and the sigmoid notch significantly differed among the three skeletal groups; however, no significant difference existed among the skeletal classes with regard to the position of the mandibular foramen in relation to the anterior and posterior borders of the ramus and the inferior border of the mandible.
Conclusions: The position of the mandibular foramen tends to be lower in skeletal class II patients; therefore, it seems that lower injection heights in these patients could result in better outcomes.
Arisha Izhar; Gurkeerat Singh; Varun Goyal; Rajkumar Singh; Nishant Gupta; Prerna Pahuja
Abstract
Objectives: The objective of this clinical study was to assess the predicted treatment outcome and actual treatment outcome and compare the models of both the groups so as to evaluate the efficacy of tooth movement with clear aligner.
Methods: The sample size included 10 cases with mild anterior crowding ...
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Objectives: The objective of this clinical study was to assess the predicted treatment outcome and actual treatment outcome and compare the models of both the groups so as to evaluate the efficacy of tooth movement with clear aligner.
Methods: The sample size included 10 cases with mild anterior crowding treated with aligner therapy. The predicted software models were superimposed on the Clinical STL models at various stages by using MeshLab software (Developed at the Visual Computing Lab at ISTI-CNR with the support of the 3D-co-form project).The predicted software models showing orthodontic tooth movement was compared with the actual movement achieved clinically. Results: The results of this study have shown that when a comparison was made on the basis of irregularity scores in both the groups, it was seen that the irregularity score was more in Clinical STL group at each stage such as 2.55 at T4, 1.65 at T6 and 1.0 at T8 whereas 2.0 at T4. 0.90 at T6 and 0.25 at T8 in the Software model group. Also, on comparing mean accuracy these three stages, the analysis of data showed the mean accuracy at T4 is 62.5%, mean accuracy at T6 is 68.8% and the mean accuracy at T8 is 78.1%.
Conclusions: The predicted software models do not accurately reflect the patient’s tooth position .There is an overestimation by predicted software as compared to the actual achieved tooth position. There is a need of overcorrection to be built in the treatment planning stage itself and execution of the anticipated end result.
Arezoo Jahanbin; Shirin Dokht Shirazi; Elaheh Kamyabnezhad; Neda Eslami; Seyed Hosein Hoseini Zarch
Abstract
Background: The spheno‐occipital synchondrosis (SOS) is an important growth center which plays an important role in cranial base development and can define the final relation of SOS with the upper and lower jaws. The morphology and fusion degree of SOS varies in different ages among different populations.
Objectives: ...
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Background: The spheno‐occipital synchondrosis (SOS) is an important growth center which plays an important role in cranial base development and can define the final relation of SOS with the upper and lower jaws. The morphology and fusion degree of SOS varies in different ages among different populations.
Objectives: Thus, the aim of this study was to evaluate the age and sex dependence of ossification of the spheno-occipital synchondrosis in the Iranian population using CBCT.
Methods: This cross-sectional retrospective study was performed on 517 CBCT images of 6- to 18-year-old patients in Mashhad, Iran. Patients with obvious pathology or fractures were excluded from the study. The SOS ossification was classified into four stages from 0 to 3. Two independent observers scored the images. The ossification stage of the SOS was classified according to the age and sex of the patients. Kruskal-Wallis and Kendall’s tau-b used for statistical analysis. Results: In this study, 517 samples of 260 females (50.3%) and 257 males (49.7%) with a mean age of 12.03 ± 3.74 years were examined. A significant difference did not exist between males and females regarding their stage of SOS ossification, although males were younger at the SOS transitional stages of 0 to 1, and 1 to 2 compared to females. Also, the SOS starts the ossification process at the age of 11 in females and 10.8 in males.
Conclusions: The present study showed in the mean age of 16.81 ± 1.12 years, most subjects were in developmental stage 3. Due to the fact that in developmental stage 3 SOS closes, there were no passive maxillary growth after this time. In none of the SOS stages, females and males differed significantly in mean age (P > 0.05). The age of the onset of SOS closure in females was 11 years and in males it was about 10.8 years.
Valiollah Arash; Farhad Sobouti; Sina Haghanifar; Iman Dabbaghian; Ali Bijani; Reza Alizadeh Navaei
Abstract
Background: Maxillary molar distalization with intraoral or extraoral appliances is a common treatment modality in non-extraction treatment plan.
Objectives: In this study, an appliance with hyrax screw was used for maxillary molar distalization. Our purpose was to evaluate the amount of molar distalization, ...
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Background: Maxillary molar distalization with intraoral or extraoral appliances is a common treatment modality in non-extraction treatment plan.
Objectives: In this study, an appliance with hyrax screw was used for maxillary molar distalization. Our purpose was to evaluate the amount of molar distalization, type of molar movement, effects on anterior teeth, and amount of changes in lower anterior facial height.
Patients and Methods: 24 class II patients (13 females, 11 males) with bilateral half cusp class II molar relationship were participated. The appliance was made by hyrax screw for producing distalization force. Pre and post distalization lateral cephalometric radiographs and dental casts were evaluated. Lateral cephalograms and study models were obtained before treatment and after 12 weeks activation of the appliance (one turn per week).
Results: Cephalometric measurement demonstrated that, first molars tipped 2.9 degrees and displaced 1.76 mm. First premolar and upper incisor tipped 3.4 and 4.2 degrees, displaced 2.9 and 2.4 mm respectively. All of these results were statistically significant. The mean of maxillary first molars distaliztion was 2.6 mm per side in approximately four month. The mean of first maxillary molars tip was 3.93˚ and the mean of anchorage loss at the first premolars was 1.95 mm, but the crowns tipped 3.45˚ mesially. Lower anterior facial height (ANS-GN) and mandibular plan angle (GO-GN) increased, 0.7 ± 0.21 mm and 0.76 ± 0.32 degree, respectively, but were statistically insignificant.
Conclusions: It can be concluded that proposed appliance can correct class II molar relationship. Molars displaced distally by bodily movement and tipping.
Cleft Lip and Palate
Daniela Garib; Raquel Silva Poletto; Thagid Yasmin Leal Almeida; Silvia Maria Graziadei; Guilherme Janson
Abstract
Aim: This study compared the prevalence of tooth agenesis out of the cleft area in patients with complete bilateral cleft lip and palate (BCLP) with and without agenesis of maxillary permanent lateral incisors.Methods: Tooth agenesis was evaluated in panoramic radiographs taken between 7 and 11 years ...
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Aim: This study compared the prevalence of tooth agenesis out of the cleft area in patients with complete bilateral cleft lip and palate (BCLP) with and without agenesis of maxillary permanent lateral incisors.Methods: Tooth agenesis was evaluated in panoramic radiographs taken between 7 and 11 years of age. Intergroup comparison of tooth agenesis frequency was performed using the chi-square test (P<0.05) and the odds ratio. A sample of 130 patients (87 male, 43 female) with non-syndromic bilateral cleft lip and palate was selected. Group P (n = 44) consisted of individuals with the presence of maxillary lateral incisors on the right and left sides; group UA (n = 40) comprised patients with unilateral agenesis of lateral incisors; group BA (n = 46) comprised patients with bilateral agenesis of lateral incisors. Intergroup comparison for frequency of tooth agenesis outside the cleft area was performed using Chi-square test (p-value <0.05 was considered significant) and the odds ratio (p<0.016).Results: The prevalence of dental agenesis out of the cleft area in groups P, UA, and BA was 31.8%, 32.5%, and 60.8%, respectively. Group BA showed a significantly greater prevalence of tooth agenesis compared with the UA and P groups. There was no significant difference in the odds ratio between any groups. The most common absent teeth were the maxillary second premolars followed by the mandibular second premolars for all groups.Conclusion: Patients with BCLP and bilateral agenesis of maxillary lateral incisors show an increased prevalence of other permanent teeth. This association demonstrates a genetic background of maxillary lateral incisor agenesis at the cleft area.
Orthodontics
Amirhossein Mirhashemi; Nasim Chiniforush; Rashin Bahrami
Abstract
Aim: Hygiene is a challenge of orthodontic treatment due to its appliances and can lead to periodontal diseases. Antimicrobial photodynamic therapy (aPDT) is a preventive technique for periodontal diseases owing to its antimicrobial and anti-inflammatory properties. The present study reviews the effect ...
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Aim: Hygiene is a challenge of orthodontic treatment due to its appliances and can lead to periodontal diseases. Antimicrobial photodynamic therapy (aPDT) is a preventive technique for periodontal diseases owing to its antimicrobial and anti-inflammatory properties. The present study reviews the effect of aPDT on the management of gingivitis induced by orthodontic treatment.Methods: The research was conducted using databases such as Scopus, PubMed, Google Scholar, and Cochrane via inputting keywords such as photodynamic therapy, photo-activated chemotherapy, photoactivated disinfection, antimicrobial photodynamic therapy, laser-activated disinfection, light-activated disinfection, laser therapy, gingivitis, gingival inflammation, and orthodontic patient. The time frame for searching articles was from January 2010 to July 2022.Results: In terms of anti-inflammatory properties, aPDT technique is associated with reductions in clinical parameters (probing depth, bleeding on probing, plaque score, and plaque index) as well as paraclinical parameters (levels of the inflammatory cytokines IL-6, TNF- α, IL-1β, and human beta defensin-2). Also, this technique has caused a decline in the number of Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Prevotella intermedia, although the effect was short-term (one month).Conclusion: The results of the study demonstrated that aPDT is an effective and safe method in reducing gingivitis induced by orthodontic treatment via its reduction effect on dental plaque, gingival inflammation, inflammatory reactions, and infective pathogens load.
Orthodontics
Fahimeh Farzanegan; Farnaz Zia; Lohrasb Dehghani; Milad Zarei
Abstract
Aim: This study aimed to investigate the effect of growth modification treatments on oral health-related quality of life in adolescents aged 11 to 14 years with Class II malocclusion.
Methods: Eighty people participated in this case-control study. The case group (n=43) included adolescents with a history ...
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Aim: This study aimed to investigate the effect of growth modification treatments on oral health-related quality of life in adolescents aged 11 to 14 years with Class II malocclusion.
Methods: Eighty people participated in this case-control study. The case group (n=43) included adolescents with a history of Class II malocclusion treated with growth modification. The control group consisted of 37 adolescents with Class II malocclusion who were not treated. Both groups were given a translation of the Child Perception Questionnaire (CPQ), measuring the quality of life in four domains: oral symptoms, functional limitations, psychological health, and social well-being. Data were statistically analyzed by SPSS software and a significance level of 0.05 was considered.
Results: The oral health-related quality of life of the case group was better than the control group in all areas although this difference was not statistically significant (P=0.204).
Conclusion: The oral health-related quality of life between two groups was not different; however, the difference in mental health components between the two groups was clinically negligible.
Bijan Moghbel; Ahmad Sodagar; Tahura Etezadi; Amirfarhang Miresmaeili
Abstract
Aim: Facial appearance is an important factor for a successful orthodontic treatment that include soft-tissue profile, finding of standard cephalometric values for various population can be useful. The aim of this study was To detect the mean soft tissue facial profile for Iranian adolescent as determined ...
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Aim: Facial appearance is an important factor for a successful orthodontic treatment that include soft-tissue profile, finding of standard cephalometric values for various population can be useful. The aim of this study was To detect the mean soft tissue facial profile for Iranian adolescent as determined by the Holdaway analysis and also detect any differences between values of boys and girls. Materials and Methods: Lateral cephalometric radiographs for 58 Iranian adolescent with normal occlusion were used. sample were consist of 35 girls (mean age 16y,7m) and 23 boys (mean age 15y,3m). All of subjects were positioned in cephalostat with the lips in rest and the teeth in centric occlusion. The landmarks were detected on the basis of Holdaway definition. Results: Iranian soft tissue showed differences in some variables when comparing to Holdaway ideal values including upper lip sulcus depth, soft-tissue subnasal to H-line, inferior sulcus to H line, skeletal profile convexity and H angle, but all of them were in the normal range. Soft tissue chin thickness was the only parameter that showed differences from normal range. When comparing two sexes, upper lip thickness and soft tissue chin thickness were greater in boys in relation to girls. Conclusions: Persian people differ from Holdaway's soft tissue norms in an increased skeletal profile convexity, H angle, and soft tissue chin thickness. These are recommended for use when formulating a treatment plan for this ethnic group. Iranian boys had thicker upper lip and greater soft tissue chin thickness in relation to girls.
Mohsen Shirazi; Elahe Soltanmohamadi Borujeni; Homa Farhadifard
Abstract
Introduction: Hemifacial microsomia (HFM) is a branchial arch syndrome and the second most common craniofacial birth defect after cleft lip and palate. This syndrome involves the facial skeleton and ear. The most important goal in treatment of HFM is to improve facial symmetry. Traditionally, segment ...
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Introduction: Hemifacial microsomia (HFM) is a branchial arch syndrome and the second most common craniofacial birth defect after cleft lip and palate. This syndrome involves the facial skeleton and ear. The most important goal in treatment of HFM is to improve facial symmetry. Traditionally, segment repositioning and costochondral graft were used for the correction of mandibular asymmetry but recently distraction osteogenesis has been used for it.
Case Presentation: In this article an 8-year-old boy with HFM is presented. He was treated with functional appliance for one year and then at 9 years age distraction osteogenesis was performed for him and at the age of 18, maxillary impaction (right side: 3mm, left side: 13 mm), BSSO of mandible and reduction genioplasty were done for the functional and esthetic reconstruction of the face.
Conclusions: Satisfactory results were obtained in the patient.
Bahman Seraj; Mandana Tosifian; Sara Ghadimi; Mohammad Javad Kharrazifard
Abstract
Background: Tooth size is an important factor that affects alignment of the teeth in the dental arch and occlusion development during dentition transition.
Objectives: This study was carried out to measure mesiodistal dimensions of primary teeth to provide standard for the tooth size. Knowledge of such ...
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Background: Tooth size is an important factor that affects alignment of the teeth in the dental arch and occlusion development during dentition transition.
Objectives: This study was carried out to measure mesiodistal dimensions of primary teeth to provide standard for the tooth size. Knowledge of such a standard of tooth size is significant for a better analysis of the space and more appropriate planning of orthodontic treatments.
Patients and Methods: The current study was conducted on 32 children, aged 5.5 - 6.5 years, in late primary dentition. The dental casts were prepared and the tooth size was measured by a digital caliper. The obtained data were analyzed by ANOVA and t-test.
Results: The mesiodistal width of primary central incisor in the upper left quadrant was larger than those of the rest of quadrants. Also, the mesiodistal widths of primary lateral incisors in the upper left quadrant, primary canines in the upper left quadrant, primary fist molars in the lower right quadrant and primary second molars in the lower left quadrant were larger than those of the other quadrants. Moreover, it was concluded that the mesiodistal diameter of permanent central incisors could be obtained according to the primary central incisors using the formula: 1.12 × (Deciduous central incisor width) + 1.27 = (Permanent central incisor width).
Conclusions: The findings of this study can be used as a base and standard for the measurement of primary dentition in Iranian children. Also, measurement of mesiodistal width of deciduous central incisors can be used to predict the mesiodistal width of permanent central incisors.
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.
Atefe Saffar Shahroudi
Abstract
Objectives: The aim of this study was to assess the effects of different orthodontic vertical loop height and design on its force characteristics at different amount of loop activation by means of finite element method (FEM) analysis. Materials and Methods: Four 3D FEM models were designed of double ...
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Objectives: The aim of this study was to assess the effects of different orthodontic vertical loop height and design on its force characteristics at different amount of loop activation by means of finite element method (FEM) analysis. Materials and Methods: Four 3D FEM models were designed of double vertical open loop (DVOL) and double vertical helical open loop (DVHOL) each of them in two heights of 6 mm and 7 mm. The loops were modeled in SolidWorks 2006 and then transferred to ANSYS Workbench. The loops were activated in buccolingual direction for 0.1, 0.3, 0.5, 0.7 and 1 mm simulating an activated multi-loop arch wire to align a posterior tooth which is erupted with buccal or lingual inclination. The force delivered at each amount of activation for the four loop designs were measured and compared. Results: The results of this study showed that the minimum amount of force was delivered by double vertical helical open loop with the height of 7 mm at the activation of 0.1 mm which was about 1.06E-01 N. The maximum amount of force was 2.2199 N which was delivered by double vertical open loop with height of 6mm at 1 mm activation. At each amount of activation the value of exerted force followed this order: DVOL 6 mm > DVOL 7 mm > DVHOL 6 mm > DVHOL 7 mm.
Conclusions: According to this FEM study, considering its limitations, adding a helix in a double vertical open loop as well as increasing the height of loop can reduce the value of delivered force.
Jasneet Singh; Gurkeerat Singh; Sridhar Kannan; Deepak Rai; Ashish Gupta; Gaurav Gupta; Raj Kumar Singh
Abstract
Background: Increase in the number of adult patients seeking orthodontic treatment for aesthetics, demand for a more aesthetic orthodontic appliance has become inevitable.
Objectives: This prospective study was undertaken to evaluate torque expression of 0.019” × 0.025” fiber composite ...
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Background: Increase in the number of adult patients seeking orthodontic treatment for aesthetics, demand for a more aesthetic orthodontic appliance has become inevitable.
Objectives: This prospective study was undertaken to evaluate torque expression of 0.019” × 0.025” fiber composite wire and 0.019” × 0.025” NiTi wire in a similar prescription bracket systems (MBT, 0.022” slot) using CBCT.
Methods: Twenty arches each (ten maxillary and ten mandibular), of 15 - 25 year old patients, were bonded with metal brackets and ceramic brackets having MBT prescription and 0.022”slot. Two CBCT images were recorded at T0 and Tx. T0 point represented the stage of transition from a 0.017” × 0.025” NiTi wire to a 0.019” × 0.025” fiber composite or NiTi archwire. The Tx time point represented the end of treatment phase using 0.019” × 0.025” dimension wire, i.e. after 3 months of T0 scan. Results: The mean angulation change from T0 to Tx in fiber composite wire group and NiTi wire group was tested using Wilcoxon signed rank test and showed that the difference was statistically non-significant (P > 0.05).
Conclusions: It was concluded that fiber reinforced composite wires were comparable to NiTi wires in their ability to deliver consistent forces and bring about comparable torque in individual teeth.
Amanda Carneiro da Cunha; Mariana Marquezan; Lincoln Issamu Nojima; Eduardo Franzotti Sant’Anna
Abstract
Background: Orthodontic mini-implants represent one of the most used anchorage systems in daily clinical practice and frequently, these anchorage devices have to be placed between the roots of adjacent teeth reflecting the need to limit its dimensions. Among other factors, it has been suggested that ...
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Background: Orthodontic mini-implants represent one of the most used anchorage systems in daily clinical practice and frequently, these anchorage devices have to be placed between the roots of adjacent teeth reflecting the need to limit its dimensions. Among other factors, it has been suggested that mini-implant’s geometry have a great impact on primary stability.
Objectives: The aim of this study was to evaluate the primary stability (PS) of commercially available orthodontic mini-implants (MI) of different geometrical designs.
Methods: Twenty self-drilling MI (1.6 mm × 8 mm) were allocated to two groups (n = 10) according to their geometric design: INP-1 and INP-2. Twenty sections (8 mm ø × 10 mm long) were taken from bovine pelve, immersed in saline solution and stored by freezing (-20°C). Geometric characteristics concerning shape, diameter, length, pitch, thread details (number, angle and depth), thread shape factor (TSF) and conicity were evaluated by using Scanning Electron Microscope (SEM) imaging and all the measurements were carried out with Image-Pro® Insight Software. PS was evaluated by insertion torque (IT) and Periotest (PTV). Intergroup comparisons were made by Student t test. The level of significance was 5%. Results: Increased IT values were observed for INP-1 (20.08 ± 3.28 N.cm) (P < 0.05), the group that presented the greatest conicity (33%) and highest thread depth (0.19 mm).
Conclusions: The wide geometric variability of MI indicates that MI design parameters affect its PS and it could be selected in order to improve its mechanical performance.
Behnam Mirzakouchaki; Reza Faraji; Mahdi Rahbar; Hadi Shirvani
Abstract
Background: Lateral cephalometry is very important for the evaluation of growth, diagnosis, treatment planning and therapeutic evaluations. Considering the advantages of lateral cephalometric analyses with the automatic technique and given the existing problems, the present study was undertaken to use ...
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Background: Lateral cephalometry is very important for the evaluation of growth, diagnosis, treatment planning and therapeutic evaluations. Considering the advantages of lateral cephalometric analyses with the automatic technique and given the existing problems, the present study was undertaken to use a new automatic technique for determination of cephalometric landmarks.
Aim: The aim of the present study was to determine the specific anatomic area by SIFT algorithm for locating cephalometric points using an automatic technique.
Methods: In this study, 110 digital lateral cephalograms were randomly selected and pre-processing was carried out on the images. Three orthodontics used these cephalograms to manually select 11 cephalometric landmarks (point A, point B, PNS, ANS, Po, Or, N, Ar, Me, Gn and Pog) on a software program which had been designed to this end. The coordinates of the selected points were saved in the database for the corresponding process of the images. After completing the software program with these data, 30 new radiographs were submitted to the software program for anatomic determination of the points. SIFT algorithm was used in the software program for the anatomic identification of the landmarks. To make a comparison, these 30 cephalograms were manually analyzed by three orthodontists in order to evaluate the accuracy of the software program at various points. Paired t-teat was used to compare the manual and computerized techniques. Statistical significance was set at P < 0.05. Results: Based on the results, the differences between the manual and automatic methods in determining cephalometric landmarks were < 1 mm in 46% of cases, < 1.5 mm in 82% of cases and < 2 mm in 100% of cases. In addition, there were no significant difference between the two method except for points Or, Po and PNS (P > 0.05).
Conclusions: It was concluded that the designed algorithm had good performance for easy and relatively difficult points. In relation to very difficult points, too, it exhibited rather acceptable performance and located the points better than other algorithms.
Majid Heidarpour; Saeid Sadeghian; Amir Siadat; Sara Siadat; Maryam Keimasi
Abstract
Objectives: The aim of this study was to evaluate and compare the effects of concomitant use of a facemask and a removable appliance and a removable appliance alone for antero-posterior expansion in Cl III children with maxillary deficiency.
Methods: In this retrospective analytical study, 21 Cl III ...
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Objectives: The aim of this study was to evaluate and compare the effects of concomitant use of a facemask and a removable appliance and a removable appliance alone for antero-posterior expansion in Cl III children with maxillary deficiency.
Methods: In this retrospective analytical study, 21 Cl III children aged 8 - 10 years were selected using the census sampling technique. The subjects were divided into two groups based on the treatment modality. In group A, the subjects received an antero-posterior-expanding removable appliance and in group B, they received the same removable appliance concomitant with a facemask. Pre- and post-therapeutic cephalograms were analyzed and changes and angles on both images were determined. Mann-Whitney U and Wilcoxon tests were used to compare the results of the two treatment modalities and before-after results respectively (α = 0.05). Results: Wits appraisal, overjet, ANB, U1-SN, U1-PP and A-B difference increased in both groups after treatment (P < 0.05). In the removable appliance group, overbite, SNB and inter-incisal angle decreased (P < 0.05). In the facemask group, IMPA decreased significantly (P < 0.05). Comparison of the two treatment modalities showed that changes in SNA, ANB, overbite, IMPA, U1-SN, U1-PP and inter-incisal angle were significant between the two groups (P < 0.05).
Conclusions: Use of a removable appliance alone or in combination with a facemask resulted in the forward movement of point A and protrusion of upper incisors. The removable appliance increased the anterior facial height and decreased overbite. A combination of facemask-removable appliance did not result in the backward and downward rotation of the mandible.
Giordana Ariane Ribeiro Schwerz Antunes de Melo; Karine Martelli; Karina Maria Salvatore de Freitas; Fabrício Pinelli Valarelli; Rodrigo Hermont Cançado
Abstract
Background: The purpose of the present study was to evaluate the influence of asthma on the degree of apical root resorption in patients treated orthodontically.
Methods: Sample comprised 683 patients treated orthodontically; 240 with asthma and 443 who did not present any kind of respiratory allergy ...
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Background: The purpose of the present study was to evaluate the influence of asthma on the degree of apical root resorption in patients treated orthodontically.
Methods: Sample comprised 683 patients treated orthodontically; 240 with asthma and 443 who did not present any kind of respiratory allergy or asthma. The Levander and Malmgren score was used for the evaluation of the degree of root resorption. This evaluation was performed in the initial and final periapical radiographs of the maxillary and mandibular incisors of all patients in the sample. Then, the sample was divided as follows: Group 1: 614 patients presenting mild or no root resorption with scores 0, 1 and 2, with mean initial age of 14.37 years, final age of 16.44 years and treatment time of 2.07 years; group 2: 69 patients who had moderate to severe root resorption with scores 3 and 4, with mean initial age of 15.09 years, final age of 17.81 years and treatment time of 2.72 years. Results: The results revealed that asthma was not a statistically significant factor for severe root resorption. The group with severe root resorption showed higher initial and final age, and longer treatment time than the group with mild root resorption. In addition, performing extractions is a risk factor for the occurrence of severe root resorption.
Conclusions: Asthma is not a risk factor for the occurrence of severe root resorption after orthodontic treatment.
Hossein Aghily; Ahmad Mosadegh; Alireza Akrami; Zahra Moradi; Mohammad Reza Hakimimeiboodi; Zahra Ebrahimi Nik
Abstract
Objectives: The aim of this study was to evaluate and compare antibacterial and antifungal effects of different concentrations of Zataria multiflora extract mouthrinse.
Methods: In this lab trial study, 128 elastomeric ligatures were divided into 2 groups of 64. Before disinfection eight ligatures of ...
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Objectives: The aim of this study was to evaluate and compare antibacterial and antifungal effects of different concentrations of Zataria multiflora extract mouthrinse.
Methods: In this lab trial study, 128 elastomeric ligatures were divided into 2 groups of 64. Before disinfection eight ligatures of each group were randomly selected to evaluate the microbial load. The remaining ligatures in each group (n = 58) were divided into 7 subgroups of 8. All samples in group 1 (G1) contaminated with Streptococcus mutans (S. mutans) and in group 2 (G2) contaminated with Candida albicans (C. albicans). Then, Zataria multiflora extract in 1%, 0.1%, 0.01%, 0.001%, 0.0001% concentrations as decontamination agent were used in 5 subgroups of each group. Positive control consisted of penicillin in G1 and nystatin in G2. For the negative control in both groups phosphate buffered saline was used. The average number of adhered viable bacterial cell after performing the disinfection protocols were calculated and compared. The collected data was statistically analyzed by Kruskal-wallis, Wilcoxon and Mann-Whitney test using SPSS software version 18 at a significant level of 0.05. Results: Results showed that penicillin, nystatin, Zataria multiflora extract in 1% and 0.1% concentrations completely eliminated C. albicans and S. mutans on elastomeric ligatures. Statistically significant differences were found between the number of adhered S. mutans and C. albicans before and after performing the all five concentrations of disinfection solutions (P = 0.01). Also higher concentrations of Zataria multiflora showed more antibacterial effectse in both groups.
Conclusions: Zataria multiflora extract mouthrinse showed antibacterial and antifungal characteristics and could be useful for patients under orthodontic treatment.
Marziyeh Shafizadeh; Azita Tehranchi; Saeed Reza Motamedian
Abstract
Context: The labial cortical bone may influence the outcomes of several treatments including fresh socket implant placement and orthodontic treatments. A thin labial plate may contribute to increased risks of periodontal consequences during dental procedures. Acknowledgment of the average values may ...
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Context: The labial cortical bone may influence the outcomes of several treatments including fresh socket implant placement and orthodontic treatments. A thin labial plate may contribute to increased risks of periodontal consequences during dental procedures. Acknowledgment of the average values may guide clinicians to take particular considerations in making treatment decisions. Therefore, this study aimed to systematically review the labial cortical bone thickness (LBT) in the anterior maxillary teeth.
Objective: The primary purpose of this study was to review the LBT in the anterior maxillary teeth to present the range of average LBT in the global population.
Evidence Acquisition: An electronic search was conducted in PubMed, Embase, ProQuest, Web of Science, and Scopus databases. English studies that measured the LBT in the maxillary anterior teeth using CT or CBCT scans were deemed relevant. Only studies performed on adult patients with a lack of periodontal disease were included.
Results: A total of 49 studies were included. Mean LBT ranged 0.13 - 3.08, 0.29 - 4.2, and 0.36 - 4.5 mm in maxillary central incisor, lateral incisor, and canine, respectively. Expectedly, LBT was affected by the vertical level of the measurement point and increased toward the apex. In total, the LBT in the anterior maxilla ranged from 0.13 to 4.5 mm. In comparison with other populations, a relatively thin labial plate was evidenced in the Iranian populations.
Conclusions: This study showed a wide range of LBT in the esthetic zone. A thin plate in the esthetic area necessitates caution in orthodontic treatments, particularly when tooth expansion or proclination is required. Additionally, wide ranges of reported values which are mostly under 2 mm, highlight the importance of CBCT acquisition before any fresh socket implant placement.
Aydin Sohrabi; Ali Rafighi; Seyed Hossein Moslemzadeh; Saeid Foroughi Moghaddam; Farzaneh Rasouli
Abstract
Background: After completion of orthodontic treatment, the retention phase is necessary for premolar teeth to preserve them in an ideal esthetic and functional relationship and to counteract the inherent tendency of teeth to return to their previous positions. Different fixed and removable retainers ...
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Background: After completion of orthodontic treatment, the retention phase is necessary for premolar teeth to preserve them in an ideal esthetic and functional relationship and to counteract the inherent tendency of teeth to return to their previous positions. Different fixed and removable retainers are used to prevent relapse in the anterior segment of the dental arch. Retainers that are bonded to 6 anterior teeth, i.e. flexible spiral wires (FSW), are more commonly used. In addition, extended bonded retainers are used to keep the extraction space closed, which are bonded to premolars in addition to anterior teeth. In orthodontic treatments involving tooth extraction, the inability of retainers to prevent the re-opening of the extraction space will result in some periodontal and occlusion problems and patient dissatisfaction.
Objectives: Therefore, the present study evaluated the ability of extended fixed retainers in comparison to FSW retainers, along with overnight use of removable retainers, to prevent re-opening of the extraction space.
Patients and Methods: Thirty-one patients (60 quadrants) were included in this study after obtaining informed consent. Convenient sampling technique was use to assign patients to two group with 13 and 27 quadrants. In group 1, an extended fixed retainer (from the second premolar on one side to the second premolar on the other side) and in group 2 FSW retainer (from the canine tooth on one side to the canine tooth on the other side) in association with overnight use of Hawley plaque were administered. Opening of the interdental space was evaluated by measuring the distance between the mandibular second premolar and first molar on each side in both groups using a leaf gauge at baseline and 2 and 6 months after placing the retainers in the oral cavity. Wilcoxon’s test was used to compare the spaces between the mandibular second premolar and first molar in each group at each time interval. Mann-Whitney U test was used to compare changes in interdental spaces between the two retainer types.
Results: The interdental spaces decreased from the time of debonding up to two months after debonding, which was statistically significant in the FSW + Hawley group (P = 0.21). During the next 4 months, the space remained unchanged in the extended FSW group and slightly increased in the FSW + Hawley group, which was not significant. In general, the interdental space decreased from the debonding session up to six months later, which was not statistically significant (P = 0.91).
Conclusions: Both extended fixed retainer and fixed retainer in association with the overnight use of Hawley restrainer were successful in keeping the extraction space closed in fixed orthodontic patients during the first 6 months.
Orthodontics
Hiral Thakkar; Brijesh Prajapati; Anar G Andani; Arth Patel; Bhavya Trivedi; Sonali Mahadevia
Abstract
Aim: The purpose of this in-vivo study is to determine and compare the accuracy of dental measurements calculated on physical and digital models with the measurements taken directly from the patients’ mouth.Methods: This study was performed on 40 subjects. Forty maxillary impressions were produced ...
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Aim: The purpose of this in-vivo study is to determine and compare the accuracy of dental measurements calculated on physical and digital models with the measurements taken directly from the patients’ mouth.Methods: This study was performed on 40 subjects. Forty maxillary impressions were produced using a condensation silicone putty material and constructed into a physical model. A digital vernier caliper was utilized to take direct measurements from the patients’ mouth as well as from the physical models. CS 3600® was employed for direct intra-oral scanning for the subjects’ dentition and generating the digital model. Three-dimensional reverse engineering software was used to make measurements on the digital model. One-way ANOVA test was used to determine the accuracy between the control group, physical models, and virtual group. Tukey’s post-hoc analysis was done to compare between the individual group.Results: There were no statistically significant differences between the physical (p-value=0.254) and virtual models (p-value = 0.168) as compared to those measurements taken directly from the mouth.Conclusion: The results of the current study demonstrate that intraoral scans are clinically sound to be used in diagnosis and treatment planning in dentistry and provide a professional and well-grounded substitute to the use of conventional plaster models.
Biomechanics
Sayyed Muhammad Ali; Javed Sodawala; Shaheen Hamdani; Sumit Gandhi; Harsha Malhotra; Gaurav Agrawal
Abstract
Aim: The purpose of this study was to compare labial and lingual forces of the rate of canine retraction and three dimensional control of the molar and canine using sliding mechanics.Methods: Ten patients with Angle’s class I malocclusion with bimaxillary protrusion referred for first premolar ...
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Aim: The purpose of this study was to compare labial and lingual forces of the rate of canine retraction and three dimensional control of the molar and canine using sliding mechanics.Methods: Ten patients with Angle’s class I malocclusion with bimaxillary protrusion referred for first premolar extraction enrolled in this split mouth study. Forty canines were placed into four groups according to the arch and type of force: UB (upper canine–labial force), LB (lower canine–labial force), UL (upper canine–lingual force), and LL (lower canine–lingual force). The rate of retraction of the canine, molar and canine rotation, molar and canine angulation, and molar anchorage loss in the sagittal and vertical plane was assessed using study models and orthopantomographs (OPG). The paired and unpaired t tests were used for intra and inter group comparison. The significance level was 0.05.Results: The rate of canine retraction was significantly faster for labial forces than lingual forces using sliding mechanics (P<0.001). However, significantly greater amount of molar rotation was observed using lingual forces (P<0.001). There was no significant difference regarding canine rotation using labial forces (P<0.05). The molar anchorage loss in the sagittal plane was significantly lesser using lingual forces (P<0.001).Conclusion: Canine retraction was faster when labial forces were applied using sliding mechanics whereas 3D-molar control was better when lingual forces were applied, which is advantageous for critical anchorage cases.
Cephalometry
Diptesh Guha; Dolly Patel; Surina Sinha
Abstract
Aim: To validate Pi angle with other sagittal discrepancy indicators like Beta angle, Yen angle and W angle in skeletal Class I, II and III patients, to correlate the Pi angle with the size and position of the mandible, and to evaluate the reliability of Dolphin imaging software.
Methods: One hundred ...
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Aim: To validate Pi angle with other sagittal discrepancy indicators like Beta angle, Yen angle and W angle in skeletal Class I, II and III patients, to correlate the Pi angle with the size and position of the mandible, and to evaluate the reliability of Dolphin imaging software.
Methods: One hundred fifty subjects were nominated based on the inclusion criteria and their lateral cephalograms were traced based on their ANB angle, they were placed into skeletal Class I, II and III groups. A-P discrepancy indicators and parameters of the size and position of the mandible were traced manually and digitally.
Results: Pi angle had 85% and 100% accuracy in identifying skeletal Class II and III groups, respectively. Parameters of the morphology of the mandible were found to have statistically significant correlation with Pi angle e.g., mandibular base length (-0.265), SNB (-0.408), articular angle (0.277), facial angle (-0.800), and Y axis (0.728), etc. When data was compared between manual and digital tracing, there was no difference in the mean values of Pi angle (P=0.87), Beta angle (P=0.73), and Yen angle (P=0.64) between the two techniques, suggesting good accuracy of Dolphin imaging software.Conclusion: The Pi angle could accurately differentiate the sample into skeletal Class I, II and III groups. A statistically significant correlation was determined between Pi angle and most of the parameters of the size and position of the mandible. It was found that the imaging software Dolphin 3D is dependable to the analysis of cephalometric variables, which are not available in the software.
Masood Feizbakhsh; Mehrdad Barekatain; Ehsan Borhani; Fatemeh Teimoori
Abstract
Aim: The aim of this study was to compare the shear bond strength [SBS] of two different light sources, light-emitting diode and quartz-tungsten halogen, under thermal cycle frequencies. Method and materials: Sixty human premolar teeth were divided into two groups, on which composite (Transbond ...
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Aim: The aim of this study was to compare the shear bond strength [SBS] of two different light sources, light-emitting diode and quartz-tungsten halogen, under thermal cycle frequencies. Method and materials: Sixty human premolar teeth were divided into two groups, on which composite (Transbond XT™ adhesive paste) cured with light-emitting diode in group I, and with quartz-tungsten halogen in group II. Samples thermocycled 500 cycles, the exposure to each bath was 10 seconds and the transfer time between the two baths was 10 seconds. 500 cycles between 5°C and 55°C were performed. An Instron testing machine [Dartec Hc.10, England] was used for the shear bond test at a crosshead speed of 1mm/min. Force was applied directly to the bracket–tooth interface. The load at failure was recorded by a personal computer connected to the test machine. SBS values were expressed in mega Pascal [MPa]. T-test was used to compare the shear bond strength between two groups. Results: The comparison of both groups indicated that the quartz-tungsten halogen groups demonstrated higher mean shear bond strength [p=19.947Mpa] than light-emitting diode groups [19.878Mpa]. There was no statistical difference in the shear bond strength values between the two light sources. [P value =0.918] Conclusions: Both light sources showed favorable shear bond strength performance and there was no statistical difference in the shear bond strength values between these two light sources.