Success Rate Of Mini-implants Research Articles

Success rate of mini-implants based on side of insertion and type of jaw in adult patients undergoing orthodontic treatment – A systematic review and meta-analysis

Objectives: To find out success rate of mini-implants based on side of insertion and type of jaw. The aim of orthodontic treatment is to maintain sufficient anchorage control to create appropriate force systems that provide the desired treatment effects. Implants have been used as skeletal anchorage devices for orthodontic purposes. Material and Methods: The following study is a systematic review of mini-screws as an intervention to evaluate the stability and different related clinical parameters to define the success rate (outcome) depending on the side of insertion (i.e., right side and left side) and type of jaw (i.e., maxilla and mandible following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses). Results and Conclusion: A total of 52 articles were extracted for qualitative synthesis among which 24 articles were reviewed for meta-analysis and the results showed that the maxilla is a better placement site for insertion of mini-implant (MI) than mandible with the odds ratio of 0.58, that is, the MI placement in the maxillary region is 58% more successful than mandibular region. The other parameter showed that the insertion of MI on the right side was more successful with the odds ratio of 0.50, that is, the insertion of MI on the right side of the jaw is 50% more successful than on the left side of the jaw.

Applications of mini-implants in orthodontics

(Salman Dental Center, Hidd) Mini-implants obtain anchorage form bone and thus provide increased control of orthodontic tooth movement and help in reducing the side effects during the management of complex malocclusion. Since the introduction of mini-implants in orthodontics, is has undergone several modifications in design, composition, size and shape. In this article, a wide-ranging review of the current application of mini-implants, the success rates of mini-implants, factors affecting the success rates of mini-implants, complications with mini-implants has been described. The utility of mini-implants has increased in the recent years. With the high success rates found with palatal mini-implants, mini-screw assisted rapid palatal expansion is popular method in contemporary orthodontics. Additionally, mini-implants with aligners can also be used to provide an esthetic option to the patients for the correction of complex malocclusion.

Prevalence and Cause of Mini-Implant Failure Encountered by Orthodontic Residents.

This study was designed to increase understanding of mini-implants as well as causes of mini-implant complications and failure in orthodontic patients. Orthodontic case sheets were evaluated to identify retraction in mini-implant cases. Samples were taken and tabulated to determine causes and sites of mini-implant failure. The overall success rate of mini-implants over a period of 3 months postplacement follow-up was 83.5%, indicating that screw implants can be used for orthodontic anchorage. To minimize failure, clinicians should attempt to reduce inflammation around screw implants.

Stainless steel or titanium mini-implants?

To investigate whether there was a difference in success rates when stainless steel (SS) was compared to titanium mini-implants (MIs) in orthodontic patients. PubMed, Cochrane, Scopus, Web of Science, Lilacs, Google Scholar, Clinical Trials, and OpenGray were searched without restrictions. A manual search was also performed in the references of the included articles. Studies comparing the success rate between SS and titanium MIs were included. Risk of bias (RoB) was assessed using the ROBINS-I (Risk of Bias in Non-randomized Studies-of Interventions) Tool or RoB 2.0 according to the study design. The level of evidence was assessed through GRADE (Grading of Recommendation, Assessment, Development, and Evaluation). Six studies met the eligibility criteria. One study was a randomized clinical trial that evaluated extraalveolar MIs, and nonrandomized trials examined interradicular MIs. The RCT presented a low RoB, two nonrandomized trials presented a moderate risk, and three presented a high risk. The quality of the evidence was high for the randomized clinical trial and moderate for the nonrandomized trials. Most studies found no difference between materials, with good success rates for both (SS, 74.6%-100%; titanium: 80.9%-100%) and only one study, with a high RoB, showed a higher success rate with titanium MIs (90%) when compared with SS (50%). A quantitative analysis was not because of the great heterogeneity among the studies. Although limited, the current evidence seems to show that the material used is not a major factor in the success rate of MIs. Because it has a lower cost than titanium and presents similar clinical efficiency, SS is a great material for orthodontic MIs.

Influence of the growth pattern on cortical bone thickness and mini-implant stability.

ABSTRACTIntroduction: Controversial reports suggest a relationship between growth pattern and cortical alveolar bone thickness, and its effect in the use of mini-implants. Objective: The main purpose of this study was to assess the influence of the growth pattern on the cortical alveolar bone thickness and on the stability and success rate of mini-implants. Methods: Fifty-six mini-implants were inserted in the buccal region of the maxilla of 30 patients. These patients were allocated into two groups, based on their growth pattern (horizontal group [HG] and vertical group [VG]). Cortical thickness was measured using Cone Beam Computed Tomography. Stability of mini-implants, soft tissue in the insertion site, sensitivity during loading and plaque around the mini-implants were evaluated once a month. Intergroup comparisons were performed using t tests, Mann-Whitney tests, and Fisher exact tests. Correlations were evaluated with Pearson’s correlation coefficient. Results: The cortical bone thickness was significantly greater in the HG at the maxillary labial anterior region and at the mandibular buccal posterior and labial anterior regions. There was a significant negative correlation between Frankfort-mandibular plane angle (FMA) and the labial cortical thickness of the maxilla, and with the labial and lingual cortical bone thicknesses of the mandible. No significant intergroup difference was found for mini-implant mobility and success rate. No associated factor influenced stability of the mini-implants. Conclusions: Growth pattern affects the alveolar bone cortical thickness in specific areas of the maxilla and mandible, with horizontal patients presenting greater cortical bone thickness. However, this fact may have no influence on the stability and success rate of mini-implants in the maxillary buccal posterior region.

Influence of orthodontic mini-implant penetration of the maxillary sinus in the infrazygomatic crest region.

Mini-implants are widely used for predictable tooth movements, but insertion is often restricted by anatomic structures. The aims of this study were to investigate the incidence of penetration of mini-implants into the sinus and the relationship between penetration depth and sinus tissue. Data from 32 patients who received mini-implants in the infrazygomatic crest were collected from a data base. The success rate of mini-implants was determined by clinical retrospective analysis. The incidence of penetration, penetration depth, and sinus configuration were investigated and compared between cone-beam computed tomography scans obtained immediately after insertion and before mini-implant removal. The overall success rate of mini-implants in the infrazygomatic crest was 96.7%, and 78.3% penetrated into the sinus. In the group in which penetration exceeded 1mm, the incidence of membrane thickening was 88.2%, and the mean value of thickening was 1.0mm; however, the variable values of penetration in the 1-mm group were only 37.5% and 0.2mm, respectively (P<0.05). The incidence of penetration of infrazygomatic crest mini-implants into the sinus may be high. Penetration through double cortical bone plates with limitation of the penetration depth within 1mm is recommended for infrazygomatic crest mini-implant anchorage.

Temporary anchorage devices (TADs) in orthodontics: review of the factors that influence the clinical success rate of the mini-implants.

The mini-implant, temporary anchorage devices (TADS), are now a common method of treatment in Orthodontics with versatility, minimal invasiveness and the relationship between costs and benefits that they offer even today. Skeletal anchorage has, to a large degree, replaced conventional anchorage in situations where anchorage is considered either critical, insufficient, or likely to result in undesirable side effects such as vertical displacements generated by inter-maxillary force systems. The objective of this study is to carry out a review about the factors that seem affect the success or failure rate of orthodontic mini-implants. A computerized literature review was performed by searching the MEDLINE database (Entrez PubMed, www.ncbi.nlm.nih.gov), Google Scholar, Scopus, Cochrane Central Register of Controlled Trials, Isi Web of Knowledge until March 2016 . The main subject heading "orthodontics" was combined with these keywords mini-implant, mini-screw, micro-implants, mini-implant success rate, mini-implant failure rate, skeletal anchorage, temporary anchorage device (TADS). In the selection process, abstracts were initially read independently by two researchers to identify potentially eligible full text papers which were then retrieved and assessed in order to decide on the final inclusion. The clinical success of orthodontic anchorage by mini-implants depends on the stability of the miniscrews used for fixation. For good stability, the application site must provide bone of good quantity and quality. We can reasonably assume that the stability of the anchorage of the mini-implants could be optimized by selecting a position with particular characteristics of quality and quantity of bone, in relation to cortical and total mandibular and jaw bone thickness. These expected informations are important because they indicates that the bone quality and quantity are significant when considering an implant placement site, but also that there are other confounding factors influencing the success rate.

Residents' journal review

Residents' journal review

Miniscrews and Mini-Implants Success Rates in Orthodontic Treatments: A Systematic Review and Meta-Analysis of Several Clinical Parameters

Introduction: The aim of the following research is to conduct a systematic review in order to update the actual knowledge about miniscrews in the clinical practice, in particular about their stability and reliability. Methods: An electronic search in the main database was performed up to February 10th, 2015 to identify articles that complied with the parameters set out in the protocol. The selection included studies showing the success rate of mini-implants for a sample exceeding 5 miniscrews, giving a definition of success, using implants with a diameter <2.5 mm and applying forces for at least 3 months. The success rate was considered as a paradigm and was divided by the following variables namely age and sex of patients, length and diameter of the miniscrew, location and method of placement of mini-implants, time and amount of loading. A meta-analysis was performed to combine comparable results. Results: 65 clinical trials that collected 4080 patients and 8524 screws were included in the study. The mean weighted overall success rate was 86.75 ± 8.48%. The maxilla represents a better placement site for insertion than the mandible. The lengths of the miniscrews do not compromise the success rate. Conclusions: In all 65 articles miniscrews could be used to help orthodontic treatment. The usage of miniscrews for a stable period of 3 months showed the highest success rates. Screws less than 8 mm in length and 1.2 mm in diameter should be used under restricted conditions, while miniscrews longer than 10 mm could be avoided.

Implants for Orthodontic Anchorage

The aims of this study were to analyze the success rate of mini-implants and miniscrews and to report the reasons behind them. An electronic literature search from PubMed databases and a hand search in implant- and orthodontic-related journals were performed until December 31, 2011. Human clinical studies in English that reported temporary anchorage devices used for orthodontic purpose with at least 6 months follow-up were included. In addition, the minimal number of implants had to be at least 10. Implants placed in maxilla, mandible, and hard palate were included. The initial search resulted in 847 articles, of which 46 were further evaluated. Finally, 29 studies were qualified and classified into 2 groups: implants placed in maxilla and mandible (group 1) and implants placed in hard palate (group 2). A meta-analysis performed for groups 1 and 2 showed 87.8% and 93.8% survival rate, respectively. In addition, the most common cause for implants failure was surgery-related factors. Mini-implant survival rate is location dependent, with those placed in the palate showing higher success rates. In addition, failures most commonly occur because of surgery-related factors.

Editor's Summary, Q & A, Reviewer's Critique: Mini-implants in orthodontics: A systematic review of the literature

Introduction In this article, we systematically reviewed the literature to quantify success and complications encountered with the use of mini-implants for orthodontic anchorage, and to analyze factors associated with success or failure. Methods Computerized and manual searches were conducted up to March 31, 2008, for clinical studies that addressed these objectives. The selection criteria required that these studies (1) reported the success rates of mini-implants on samples sizes of 10 implants or more, (2) gave a definition of success, (3) used implants with a diameter smaller than 2.5 mm, and (4) applied forces for a minimum duration of 3 months. Factors associated with implant success were accepted only if potentially influencing variables were controlled. The Cochrane Handbook for Systematic Reviews of Interventions was used as the guideline for this article. Results Nineteen reports met the inclusion criteria, but definitions of success, duration of force application, and quality of the methodology of these studies varied widely. Rates of primary outcomes ranged from 0% to 100%, but most articles reported success rates greater than 80% if mobile and displaced implants were included as successful. Adverse effects of miniscrews included biologic damage, inflammation, and pain and discomfort. Only a few articles reported negative outcomes. All proposed correlations between clinical success and specific variables such as implant, patient, location, surgery, orthodontic, and implant-maintenance factors were rejected because they did not meet the selection criteria for controlling those variables. Conclusions Mini-implants can be used as temporary anchorage devices, but research in this field is still in its infancy. Interpretation of findings was conditioned by lack of clarity and poor methodology of most studies. Questions concerning patient acceptability, rate and severity of adverse effects of miniscrews, and variables that influenced success remain unanswered. This article includes a guideline for future studies of these issues, based on specific definitions of primary and secondary outcomes correlated with specific operational variables.

Mini-implants in orthodontics: A systematic review of the literature

In this article, we systematically reviewed the literature to quantify success and complications encountered with the use of mini-implants for orthodontic anchorage, and to analyze factors associated with success or failure. Computerized and manual searches were conducted up to March 31, 2008, for clinical studies that addressed these objectives. The selection criteria required that these studies (1) reported the success rates of mini-implants on samples sizes of 10 implants or more, (2) gave a definition of success, (3) used implants with a diameter smaller than 2.5 mm, and (4) applied forces for a minimum duration of 3 months. Factors associated with implant success were accepted only if potentially influencing variables were controlled. The Cochrane Handbook for Systematic Reviews of Interventions was used as the guideline for this article. Nineteen reports met the inclusion criteria, but definitions of success, duration of force application, and quality of the methodology of these studies varied widely. Rates of primary outcomes ranged from 0% to 100%, but most articles reported success rates greater than 80% if mobile and displaced implants were included as successful. Adverse effects of miniscrews included biologic damage, inflammation, and pain and discomfort. Only a few articles reported negative outcomes. All proposed correlations between clinical success and specific variables such as implant, patient, location, surgery, orthodontic, and implant-maintenance factors were rejected because they did not meet the selection criteria for controlling those variables. Mini-implants can be used as temporary anchorage devices, but research in this field is still in its infancy. Interpretation of findings was conditioned by lack of clarity and poor methodology of most studies. Questions concerning patient acceptability, rate and severity of adverse effects of miniscrews, and variables that influenced success remain unanswered. This article includes a guideline for future studies of these issues, based on specific definitions of primary and secondary outcomes correlated with specific operational variables.

The effect of cortical bone thickness on the stability of orthodontic mini-implants and on the stress distribution in surrounding bone

Cortical bone thickness (CBT) was evaluated at mini-implant placement sites in 65 orthodontic patients and was found to be directly proportional to the success rate of the mini-implant. The success rate of the mini-implant was significantly greater at sites with CBT ≥ 1.0 mm. To examine the biomechanical effects of CBT, finite element models were made for CBT from 0.5 to 1.5 mm, at 0.25-mm intervals. Cortical bone models without cancellous bone were constructed to examine the biomechanical influence on cortical bone after cancellous bone resorption. CBT influenced the stresses in the cancellous bone, but could not directly influence the stresses in the cortical bone. For CBT < 1 mm, the cancellous bone models exhibited von Mises stresses exceeding 6 MPa, and the cortical bone models without cancellous bone showed von Mises stresses exceeding 28 MPa. Greater CBT values were associated with higher mini-implant success rates. This morphometric study and mathematical simulation verify that a clinical CBT threshold of 1 mm improves the success rate of mini-implants.

Application of orthodontic mini-implants in adolescents

The aim of this study was to determine the success rate of mini-implants in adolescents, and also whether a latent period is necessary and the optimum placement torque in an attempt to improve the success rate in adolescent patients. There were 57 orthodontic patients involved in the study, with ages ranging from 11.7 to 36.1 years, who underwent surgery to insert mini-implants (169 implants). When a mini-implant endured an orthodontic force applied for 6 months or more without any mobility, it was considered a success. The success rate was 63.8% in the early-load group (less than 1-month latent period) of adolescents, 97.2% in the late-load group (3-month latent period) of adolescents and 91.9% in the adult group. The success rate of the early-load group of adolescents was significantly inferior to those of the other groups ( P < 0.01). In measurements of the placement torque in adolescents, the success rate of the 5–10 N cm group was significantly higher than the other groups only in the maxilla of the early-load group. Although the optimum torque could not be defined, a latent period of 3 months before loading is recommended to improve the success rate of the mini-implant when placed in the alveolar bone in adolescent patients.

Recommended placement torque when tightening an orthodontic mini‐implant

To determine an adequate placement torque for obtaining a better success rate of mini-implants that are screwed into the buccal alveolar bone of the posterior region as an anchor for orthodontic treatment, implant placement torque (IPT) was measured. The subjects were 41 orthodontic patients (124 implants), with an average age of 24.9 years (SD 6.5 years), who had surgery to place titanium mini-implants. The peak value of IPT was measured using a torque screwdriver. The success rate of the mini-implant anchor for 124 implants was 85.5%. The mean IPT ranged from 7.2 to 13.5 N cm, depending on the location of the implants. There was a significant difference in the IPT between maxilla and mandible. The IPT in the mandible was, unexpectedly, significantly higher in the failure group than in the success group. Therefore, a large IPT should not be used always. According to our calculations of the risk ratio for failure, to raise the success rate of 1.6-mm diameter mini-implants, the recommended IPT is within the range from 5 to 10 N cm.