Success and Failure Rates of Orthodontic Mini-screws: A Systematic Review
Massoud
Seifi
Professor of Orthodontics, Dentofacial Deformities Research Center, Shahid Beheshti University of Medical
Sciences, Tehran, Iran
author
Negin Sadat
matini
Department of Orthodontics, Shahid Beheshti University of Medical Sciences, Tehran, Iran
author
text
article
2014
eng
Aim: The purpose of the present study was to systematically review the literature on the success and failure of the miniscrews.Materials and Methods: Titles and abstracts in Medline Databases (PubMed) were screened by 2 reviewers. First result contains 273 articles, after search filters they have reached to 9 articles. All articles were discussed by 2 reviewers and disagreements were solved.Results: The total success rate were available in all 9 studies and ranged from 70.3% to 96%. The number of treated patients were ranged from 15 to 141and also the number of miniscrews ranged from 44 to 260. The success and failure rates of miniscrews in these 9 studies had no significant correlation with gender. Statistic methods are different among these clinical trials.Conclusion: It seems that weak consensus exist between bulk of data obtained from different clinical trials. Gender has been mentioned as a predisposing factor for success or failure rate and some article reported more success for male, some for female, and some no difference. Immediate loading has more success rate according to some investigations but many investigators suggest a healing period and delayed loading. Diameter and length of miniscrews and their dispersion factor is another source of inconsistency among authors. Diameters start from (in millimeter) 1.2, 1.3, 1.6-1.8 to 2 mm and length starts from (in millimeter) 5, 6,7,8 to 10 mm and different success rate is reported for these parameters. Even success or failure rate is described differently among clinicians and it start from stability during first one week, extends to six month and two year. In addition, some authors believe that because of the pool of subjects (large sample with important elements) in retrospective studies, appropriate statistics are Kaplan-Meier survival curves based on rigorous clinical success or failure criteria instead of success or failure rate.
Iranian Journal of Orthodontics
Iranian Association of Orthodontists
1735-5087
9
v.
1
no.
2014
1
7
https://www.ijorth.com/article_247407_356703cf4d6ce4308b80413cd8eeab29.pdf
dx.doi.org/10.22034/ijo.2014.247407
Relationship between Mid-palatal Bone Thickness and Facial Height Using CBCT for Orthodontic Mini-implant
S.
NaghiNejad Ahmadi
Post-graduate Student of orthodontics, Faculty of Dentistry, Tabriz University of Medical Sciences,
Tabriz, Iran
author
Mojgan
Kochoei
Associate Professor of orthodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran
author
text
article
2014
eng
Aim: Orthodontic mini-implants have been incorporated into orthodontic treatment modalities. Adequate bone at mini-implant placement site can influence the success or failure of anchorage. The aim of the present study was to determine the thickness of bone in the maxillary mid-palatal area at predetermined points for the placement of orthodontic mini-implants using Cone Beam CT technique in order to evaluate the relationship of these values with the facial height.
Materials and methods: A total of 161 patients, consisting of males (39.32%) and females (60.86%), were evaluated in the present study, 38% of the subjects had normal facial height, 29% had short face and 33% had long face. In order to determine which patient belonged to which facial height category, i.e. normal, long or short, two angular and linear evaluations were used: the angle between S-N and Go-Me lines and the S-Go to N-Me ratio. Twenty points were evaluated in all the samples. First the incisive foramen was located. The para-coronal cross-sections were prepared at distances of 4, 8, 16 and 24 mm from the distal wall of the incisive foramen and on each cross-section the mid-sagittal and para-sagittal areas were determined bilaterally at 3- and 6-mm distances (a total of 5 points). The thicknesses of the bone were determined at the predetermined points. Results: Statistical analysis did not show significant differences between three different facial height groups at none of the 20 points.Conclusion: The present study did not find any relationship between palatal bone thickness and facial height. Further studies with larger sample size are necessary to evaluate the relationship between the thickness of bone and facial height.
Iranian Journal of Orthodontics
Iranian Association of Orthodontists
1735-5087
9
v.
1
no.
2014
8
12
https://www.ijorth.com/article_247408_3649e003964cc4bfd94d523f4315df14.pdf
dx.doi.org/10.22034/ijo.2014.247408
Cephalometric Comparison of a Modified Bionator (Farmand Appliance) and Twin-Block Appliance in Treatment of Skeletal Cl II Malocclusion
Mohammad Karim
Soltani
Assistant professor, Department of Orthodontics, Dental Faculty, Hamadan University of Medical
Sciences, Hamadan, Iran
author
Amirfarhang
Miresmaeili
Associate professor, Department of Orthodontics, Dental Faculty, Hamadan University of Medical
Sciences, Hamadan, Iran
author
Bahareh
Javanshir
postgraduate student of orthodontics, Department of Orthodontics, Dental Faculty, Hamadan
University of Medical Sciences, Hamadan, Iran
author
Mojgan
AkbarZadeh
Ph.D. candidate in biostatistics , biostatistics and epidemiology department, health faculty ,Hamadan
University of Medical Sciences, Hamadan, Iran
author
text
article
2014
eng
background and aim: functional appliances with various designs have been introduced in the treatment of Class II malocclusions. The aim of this study was to evaluate dentoskeletal effects of a modified bionator (FA) and Twin Block (TB) functional appliance in treatment of skeletal Class II malocclusion.Method and material: in this retrospective study 30 treated cl II patients with overjet greater than 4mm have been selected from each of two private offices .in each office either FA or TB were used. Pre-treatment and post-treatment lateral cephalograms were digitized and traced with Dolphin Imaging software. ANCOVA and paired T test were used for analysis with SPSS software (19).Results: FA group consisted of 17 girls and 13 boys(mean age: 9.53± 1.1), TB group consisted of 12 boys and 18 girls(mean age: 10.26 ±.944 ) .ANB angle and overjet were reduced significantly in both groups. (p=.000) Mandibular body length demonstrated a significant increase in both groups( 3.06±4.98mm with TB and 3.03±5.52mm with FA ). In Both appliances significant retrusion of upper lip occurred as a result of decrease in overjet (TB=002, FA=.000). No statistical significant difference were found between two appliances.Conclusions: Treatment with both appliances resulted in correction of Class II discrepancy, reduction of overjet, and retrusion of upper lip. No significant dento-skeletal differences were observed between the 2 appliances.
Iranian Journal of Orthodontics
Iranian Association of Orthodontists
1735-5087
9
v.
1
no.
2014
13
20
https://www.ijorth.com/article_247409_a55133625dbf330d10256c7f374302fd.pdf
dx.doi.org/10.22034/ijo.2014.247409
An Innovative Non-Compliant Interceptive Approach for 3-Dimensional Class II Defect in Mixed Dentition
A.V.
Jumle
(B.D.S., M.D.S.) Practitioner and Orthodontic consultant at Om Dental Clinic- Orthodontic Care &
Implant Center, Pune, Maharashtra, India
author
N.
Toshniwal
Prof. and Head,Department of Orthodontics and Dentofacial Orthopedics, Rural Dental College,
Loni, India
author
text
article
2014
eng
Aim: The aim of this study was to intercept the Class II Div 1 malocclusion with 3 dimensional defects early in mixed dentition to reduce its severity, so to avoid the psychological trauma, in this poor non-compliant patient, which would also be cost effective.Method: A combination appliance, which would consider all 3 dimension, be cost effective and which would not depend on patient for compliance was a need for this patient. So an innovative approach of using a maxillary expansion plate with the incline plate as that of twin block but which can be cemented to the arch and prism shaped composite blocks as that of Planas Direct Tract on the mandibular second deciduous molar was designed. As soon as the appliance was bonded, profile was improved. Results and conclusion: At the end of 8 months of active treatment, there was improvement in transverse, sagittal and vertical dimension with the satisfaction of the patient and the parent. The fabricated combination appliance, proved successful for intercepting the condition, satisfying the patient and parent by improving psychological condition along with the Class II condition. It was decided to name the appliance as 3D RDC CORRECTOR [3 dimensional (institution name) corrector].
Iranian Journal of Orthodontics
Iranian Association of Orthodontists
1735-5087
9
v.
1
no.
2014
21
25
https://www.ijorth.com/article_247410_429aa350bb50b62957da378a46f8dfb3.pdf
dx.doi.org/10.22034/ijo.2014.247410
Prevalence of Crossbite Malocclusion among 7-10 Years-Old Children in Yazd, in 2012
Navid
Hosseini
Assistant professor, Department of Orthodontics, Yazd University of Medical Sciences
author
H.
Azadikhah
Under graduate student , School of Dentistry, Yazd University of Medical Sciences
author
Soghra
Yassaie
Associate professor, Department of Orthodontics, Yazd University of Medical Sciences
author
Mohammad
Tayyebi
Associate professor, Department of Orthodontics, Yazd University of Medical Sciences
author
text
article
2014
eng
Background and aim: cross bite is an Abnormal relationship between one or more teeth and their corresponding antagonist tooth so that the buccolingual or labiolingual relationship is opposite. Given the high prevalence and impact of these disorders, diagnosis and early treatment of this problem is very important. The aim of this study is to determine the prevalence of anterior and posterior cross bite for girls and boys who were 7-10 years old in Yazd, Iran.Materials and methods: This cross-sectional study on 400 students aged 7-10 was carried out using clinical examination. Examinations were performed by the dentist and the presence or absence of crossbite and occlusal relationship was evaluated in the mixed dentition.Results: The prevalence of anterior cross bite is 11% ,12.9% of girls and 9% of boys and prevalence of posterior cross bite was 3.5%, 4.5% in girls and 2.5% in boys. prevalence of anterior cross-bite at age 9 was 11.9% and posterior cross bite at age 10 was 7.1% which are the highest rates reported .In mouth breathing children 35.7% and 21.4%, had anterior and posterior cross bite respectively. The anterior and posterior cross bite was more in Class II malocclusion than any other malocclusion. Among the cases investigated, mouth breathing and malocclusion have correlation with crossbites.Conclusion: Given the prevalence of anterior and posterior cross bite, mothers should be awared on the prevention and control of these disorders and also periodic examinations of children To prevent complications in future.
Iranian Journal of Orthodontics
Iranian Association of Orthodontists
1735-5087
9
v.
1
no.
2014
26
30
https://www.ijorth.com/article_247411_9964df1062e444e084c2dfb39d37a46b.pdf
dx.doi.org/10.22034/ijo.2014.247411
The Effect of ZnO Nanoparticles on Resistance to Sliding of Nickel Titanium Orthodontic Wires
Mojgan
Kachoie
Associate professor. Dental and Periodontal Research Center, Department of Orthodontics, Faculty
of Dentistry, Tabriz University of Medical Sciences
author
Baharak
Divband
Associate professor. Dental and Periodontal Research Center, Department of Orthodontics, Faculty
of Dentistry, Tabriz University of Medical Sciences
author
Masoumeh
khatamian
Department of Inorganic Chemistry, Faculty of Chemistry, Tabriz University
author
Azin
Nourian
postgraduate student of orthodontics. Department of Orthodontics, Faculty of Dentistry, Tabriz
University of Medical Sciences
author
text
article
2014
eng
Introduction: NiTi wires which are considered the ideal alloys used during the alignment and leveling stage of comprehensive orthodontic treatment exhibit very high frictional resistance. Therefore, overcoming such resistance to sliding results in a rapid tooth movement and proper anchorage control. Recently, coating the wires with nanoparticles has been introduced to decrease resistance to sliding. The aim of this invitro study was to evaluate effect of ZnO nanoparticles on resistance to sliding of nickel titanium orthodontic wires. Materials and methods: 40 straight pieces of 0.016-inch NiTi wires were evaluated in two groups with and without spherical ZnO nanoparticle coating, along with 40 standard system 0.018 stainless steel brackets. ZnO nanoparticles were deposited on NiTi wires and analyzed by SEM. A universal testing machine was used to determine friction between the wires and brackets at an angle of 5°. Student’s t-test were used for data analysis. Results: The SEM results confirmed the homogeneous deposition of ZnO nanoparticles on NiTi wires. At 5º angle between the wires and brackets the means of frictional forces were 1.2475±0.13 and 1.5075±0.12 N with and without ZnO nanoparticle deposits on the wires, respectively, revealing a significant decrease of 17.24% in frictional forces in coated wires (P<0.001).Conclusion: Based on the results of this study, ZnO nanoparticle coating reduces the resistance to sliding of nickel titanium orthodontic wires.
Iranian Journal of Orthodontics
Iranian Association of Orthodontists
1735-5087
9
v.
1
no.
2014
31
36
https://www.ijorth.com/article_247412_73d8dc7f65575564fd6ad9c792e55e5f.pdf
dx.doi.org/10.22034/ijo.2014.247412
A Retrospective Cephalometric Evaluation on Location of Center of Mandibular Autorotation after Le Fort I Superior Repositioning Osteotomy
Tahereh
Hosseinzadeh Nik
Professor, Dental research center, Dentistry research institute, Tehran University of Medical Sciences,
Tehran, Iran And Department of Orthodontics, Faculty of Dentistry, Tehran University of Medical
Sciences, Tehran, Iran
author
Elham Sadat
Emdadian Razavi
Postgraduate student, Orthodontic department, Dental school, Tehran University of Medical Sciences
author
Afsaneh
Modarresi
Postgraduate student, Oral and maxillofacial surgery department, Dental school, Azad University of
Medical Sciences
author
Mobina
Mollaei
Postgraduate student, Orthodontic department, Dental school, Azad University of Medical Sciences
author
text
article
2014
eng
Introduction: A possible treatment option for non-growing patients with vertical maxillary excess (VME), is superior repositioning of maxilla with or without mandibular surgery. After maxillary impaction, mandible rotates around a center. A common assumption at the time of cephalometric prediction, is taking condyle as an unchangeable center of rotation. Any error in determination of center of mandibular autorotation (CMA) may lead to improper jaw positioning and unaesthetic results.
Materials and methods: In this study, before and after cephalometric radiographs from fourteen orthognathic patients with maxillary impaction were evaluated.
Results: showed that center of mandibular autorotation are not similar in different patients, partly because of individualized craniofacial morphology. Therefore, precise determination of center of mandibular autorotation is necessary for obtaining ideal results.
Iranian Journal of Orthodontics
Iranian Association of Orthodontists
1735-5087
9
v.
1
no.
2014
37
42
https://www.ijorth.com/article_247413_a0f1bc8dd40e839afb1c95ce595757c4.pdf
dx.doi.org/10.22034/ijo.2014.247413
Dentofacial Relapse in Class II Patients Treated with Functional Appliances
Soghra
Yassaei
Associate professor, Department of Orthodontics, Faculty of Dentistry, Shahid Sadoughi
University of Medical Sciences, Yazd, Iran
author
Farzaneh
Eslami
Postgraduate student, Department of Orthodontics, Faculty of Dentistry, Shahid Sadoughi
University of Medical Sciences, Yazd, Iran
author
Roya
Ghafouri fard
Postgraduate student, Department of Pediatrics, Faculty of Dentistry, Shahid Sadoughi
University of Medical Sciences, Yazd, Iran
author
text
article
2014
eng
Aim: Considering the importance of stability on the orthodontic treatment outcomes, the instability may cause dentoskeletal and soft tissue changes in patients after the treatment. The aim of this study was to evaluate dentoskeletal and facial soft tissue relapse in class II patients whom have been treated with functional appliances. Materials and Methods: 23 patients with Class II Division 1 malocclusion who had received treatment with Farmand functional appliance and had at least two years of post treatment follow up, were evaluated using cephalometric analysis for dentoskeletal and soft tissue changes. The lateral cephalometric radiographs of the patients immediately after the treatment (T1) and two years follow up (T2) were traced and statistical analysis was performed to obtain the amount of occurred relapse between T1 and T2.Results: The mean decrease of ANB angle between T1 and T2 was 0.73 º, which was not statistically significant. Overall, the mean changes of skeletal and dental variables (FMA, GOGN-SN, U1 to SN, U1 to FH and IMPA) in T1 and T2 were not statistically significant. For the soft tissue variables, the mean increase of the nasolabial and mentolabial angle in T1 and T2 were not significant. The mean changes of Z and H angles in T1 and T2 were 0.53º and 0.63 º, which were not statistically significant. Conclusion: Dentoskeletal and soft tissue facial changes that occurred during treatment with Farmand functional appliance remained stable at least 2 years after treatment.
Iranian Journal of Orthodontics
Iranian Association of Orthodontists
1735-5087
9
v.
1
no.
2014
43
49
https://www.ijorth.com/article_247414_6060130e7eedd866150e1cbbbe0ab6d2.pdf
dx.doi.org/10.22034/ijo.2014.247414