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.
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.
Massoud Seifi; Negin Sadat matini
Abstract
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 ...
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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.
