Stability Of Orthodontic Mini-implants Research Articles

Effect of Splinting on Orthodontic Mini-Implant Tipping and Bone Histomorphometric Parameters: An In Vivo Animal Model Study

This study aimed to address the stability of orthodontic mini-implants submitted to an immediate orthodontic functional load, in splinted or unsplinted conditions, further characterizing the histomorphometric parameters of the neighboring bone tissue, in an in vivo experimental model. Mini-implants (1.4 × 6.0 mm) were placed in the proximal tibia of New Zealand White rabbits and immediately loaded with a 150 g force. Tissue healing was characterized within 8 weeks. Microtomography was used to assess the mini-implants' tipping and bone histomorphometric indexes. Loaded implants were evaluated in splinted and unsplinted conditions, with data being compared to that of unloaded mini-implants with the Kruskal-Wallis nonparametric test, followed by Dunn's multiple comparison tests. The splinting of mini-implants submitted to immediate orthodontic loading significantly reduced the tipping to levels similar to those of unloaded mini-implants. Immediate loading further increased the histomorphometric indexes associated with bone formation at the peri-implant region, in both splinted and unsplinted conditions, with no significant differences between the tension and compression regions. Accordingly, within this experimental setting, splinting was found to lessen tipping and mini-implants' displacement, without affecting the increased bone formation at the peri-implant region, induced by a functional orthodontic load.

In-vitro investigation of primary stability of orthodontic mini implants with different lengths using resonance frequency analysis

Out of various ways of gaining anchorage, mini implants are gaining attention due to its minimum compliance and maximum curative effects.Mini implants are considered successful if they have sufficient primary stability that comes from mechanical interlocking of mini implant with the bone.Factors which influence the implant stability are bone physiology, implant size, shape and surface characteristics. Considering all other factors within anatomic constraints, what may play a role in primary stability of mini implants is length. Literature search to correlate mini implant length with primary stability was found to be insufficient and hence this study was undertaken. In this study, two goat jaws were subjected to spiral 3D CT scan and the areas with D2 bone density were identified and marked. In these D2 density marked areas, 30 implants of 1.5 x 6mm (GROUP A) and 30 implants of 1.5 x8mm (GROUP B) were placed. Their stability was measured by Radio Frequency Analysis using Osstell ISQ device with its Smart Peg. A connector was fabricated to make the fit of smart peg compatible with the head of mini implant. Readings were made in 5 different directions for each implant and their average value was considered as final reading. It was noted that primary mini implant stability is significantly higher (p 0.034) with GROUP B implants than with GROUP A implants. The increased length of mini-implants positively affects its primary stability and should be taken into consideration when implants are used as anchorage devices.

The Effect of Photobiomodulation Therapy on the Stability of Orthodontic Mini-implants in Human and Animal Studies: A Systematic Review and Meta-analysis.

Introduction: The present study aimed to systematically explore available literature on the possible impact of photobiomodulation (PBM) therapy on the stability and success of orthodontic mini-implants. Methods: A comprehensive electronic search was conducted in PubMed, ISI Web of Science, Scopus, Cochrane and Embase databases for human and animal studies published until July 2021. Two independent researchers reviewed the studies based on specific eligibility criteria. Results: 15 studies were included in the systematic review after a comprehensive search. Ten studies were included in the meta-analysis. Four were human RCT studies that evaluated the stability with Preriotest. Three other human RCT studies and two animal studies had evaluated the Implant stability quotient (ISQ). Two human RCTs that had evaluated displacement of mini-implants were also analyzed. The analysis of Periotest stability results showed a positive effect of PBM on mini-implant stability at 30 and 60 days after implantation (P<0.05). In human studies using the ISQ method, a slight improvement was seen in the PBM groups; however, this was not statistically significant (CI=-1.92-2.70, SMD=0.39). In studies that examined the displacement of mini-implants, no statistically significant difference was observed between irradiated and non-irradiated groups (CI=-1.92-2.70, SMD=0.03). According to the results of animal studies, which had used the ISQ method, the use of laser was statistically effective in increasing the stability of mini-implants (SMD=1.43, CI=1.00-1.85). Conclusion: PBM therapy can be suggested as an adjunctive clinical method to improve the stability of mini-implant treatment. Further well-designed clinical studies can help establish evidence-based dosing and irradiation protocols.

Significance of bone morphology and quality on the primary stability of orthodontic mini-implants: in vitro comparison between human bone substitute and artificial bone.

This study evaluated artificial bone models against ahuman bone substitute to assess the primary stability of orthodontic mini-implants (OMIs) at varying implant sites with different morphologies and qualities. Atotal of 1200 OMI placements of four types were inserted into four artificial bone models of different density (D1, D2, D3, D4) and into ahuman bone substitute (HB). The implants varied in diameter (2.0 and 2.3 mm) and length (9and 11 mm). Each specimen had four implant sites: no defect, one-wall defect, three-wall defect, and circular defect. The implant stability quotient (ISQ) values were measured using resonance frequency analysis (RFA) and insertion placement torque values (IPT) were assessed for primary stability. Correlation analysis was performed to evaluate the different models. The highest IPT value was registered for the 2.0 mm × 11 mm implant inserted into D1 with no defect (37.53 ± 3.02 Ncm). The lowest ISQ value was measured for the 2.3 mm × 9 mm OMI inserted into D3 with acircular defect (12.33 ± 5.88) and the highest for the 2.3 mm × 9 mm implant inserted into HB with no defect (63.23 ± 2.57). Astrong correlation (r = 0.64) for IPT values and avery strong correlation (r = 0.8) for ISQ values was found between D2 and HB. Bone defects and bone quality affected the primary stability of implants in terms of ISQ and IPT values. Results for bone model D2 correlated very well with the HB substitution material.

Photobiomodulation and its Effect on Stability of Orthodontic Mini-implants: A Systematic Review and Meta-analysis of Randomised Controlled Trials

Introduction: The influence of Photobiomodulation (PBM) in the field of orthodontics has been of recent interest. PBM has a promising effect on acceleration of tooth movement, alleviation of pain during orthodontic treatment and Mini-Implant (MI) stability. Aim: The aim of this review was to systematically report on the effectiveness of PBM on the stability of orthodontic MI. Materials and Methods: Literature search was conducted in five electronic databases for human trials published between January 2000 to February 2021 on the effectiveness of PBM therapy for stability of orthodontic MI. This systematic review was conducted during January 2021 and February 2021. Cochrane review manager software (Revman version 5.4) and Cochrane Risk Of Bias (ROB) 2 tool were used for bias assessment. The primary outcome measured was the stability of MI using Resonance Frequency Analysis (RFA) or Periotest Value (PTV). The secondary outcomes measured were pain and inflammation around the peri-implant area. Also, Interleukin-1β (IL-1β) was also measured in gingival crevicular fluid. Results: A total of six Randomized Controlled Trials (RCTs) were included in the review. Out of the 6 studies, 2 showed low Risk Of Bias (ROB) whereas 3 showed some concerns and 1 showed high ROB. Quantitative analysis was done for 4 studies with a random effects model to assess the MI stability measured by periotest at 30 days and 60 days. A significant mean difference of -3.31 (95% CI-5.15,-1.47) between PBM and controls for mini-implant stability at 30 days and a significant mean difference of -3.47 (95% CI-4.58, -2.36) between PBM and controls at 60 days with low heterogeneity was obtained. Three studies reported on the pain response after PBM and both groups showed no significant difference. A decrease in gingival inflammation was reported in one study whereas other study showed no significant change in IL-1ß in gingival crevicular fluid. Conclusion: Majority of the studies included in this review reported improved secondary stability with PBM. The low heterogeneous nature of the quantitative studies also supports the data obtained. However, the results should be concluded with caution.

Effect of placement angle, diameter, length and bone density on the pull-out strength of orthodontic mini-implants: An in vitro study.

To evaluate the effect of the placement angle, diameter, length and bone density on the mechanical stability of orthodontic mini-implants by measuring their pull-out strengths. A total of 120 mini-implants of four different dimensions made from titanium were used. They measured 1.3 × 6.0mm, 1.3 × 8.0 mm, 1.5 × 6.0 mm and 1.5 × 8.0 mm. Synthetic polyurethane bone blocks (Saw Bones, USA) in two different densities were used. Each size of mini-implant was inserted equidistantly into synthetic bone blocks of two different densities, in three different insertion angles of 30°, 60° and 90°. This resulted in 24 test groups with five mini-implants allocated to each group. The pull-out strength was measured using an Instron Universal Testing Machine exerting a vertical force parallel to the long axis of the mini-implant until removal or failure occurred. Peak load at failure of the mini-implant was recorded in kN. Showed that mini-implants placed at an insertion angle of 30° offered least resistance to pull-out. Mini-implants 6.0 mm in length showed less pull-out strength compared to the longer 8.0-mm mini-implants. Mini-implants 1.3 mm in diameter provided similar pull-out values as 1.5-mm mini-implants. Bone densities of 0.20 g/cc and 0.32 g/cc did not affect the pull-out strength of mini-implants. From the study, it was concluded that a logical choice of mini-implant dimension and prudent use of placement technique can help achieve the treatment goals with a reduced hazard of mini-implant failure.

Significance of photobiomodulation therapy in increasing stability of orthodontic mini-implants: a systematic review and meta-analysis

Significance of photobiomodulation therapy in increasing stability of orthodontic mini-implants: a systematic review and meta-analysis

Impact of Implant Design and Bone Properties on the Primary Stability of Orthodontic Mini-Implants

This study investigated the correlation between bone characteristics, the design of orthodontic mini-implants, the pull-out force, and primary stability. This experimental in vitro study has examined commercial orthodontic mini-implants of different sizes and designs, produced by two manufacturers: Tomas-pin SD (Dentaurum, Ispringen, Germany) and Perfect Anchor (Hubit, Seoul, Korea). The total number of 40 mini-implants were tested. There are two properties that are common to all tested implants—one is the material of which they are made (titanium alloy Ti-6Al-4V), and the other is the method of their insertion. The main difference between the mini-implants, which is why they have been selected as the subject of research in the first place, is reflected in their geometry or design. Regardless of the type of implant, the average pull-out forces were found to be higher for a cortical bone thickness (CBTC) of 0.62–0.67 mm on average, compared to the CBTC &lt; 0.62 mm, where the measured force averages were found to be lower. The analysis of variance tested the impact of the mini-implant geometry on the pull-out force and proved that there is a statistically significant impact (p &lt; 0.015) of all three analyzed geometric factors on the pull-out force of the implant. The design of the mini-implant affects its primary stability. The design of the mini-implant affects the pulling force. The bone quality at the implant insertion point is important for primary stability; thus, the increase in the cortical bone thickness increases the value of the pulling force significantly.

Is gingival biotype a critical determinant of secondary stability of orthodontic mini-implants – A prospective clinical study using resonance frequency analysis

Objectives: The objectives of the study were to determine the association of gingival biotype and secondary stability of orthodontic mini-implants using resonance frequency analysis. Materials and Methods: Twenty patients, each receiving two mini-implants, were divided into two groups; thick and thin gingival biotype based on the thickness of gingiva before mini-implant placement. Implant stability was assessed at the time of placement; at the 1st, 2nd, 3rd, and 4th month by resonance frequency analysis. Peri-implant soft-tissue conditions were also examined at each month till 4 months interval using periodontal indices. Results: Thick and thin gingival biotype groups showed statistically different implant stability quotient (ISQ). Mini-implants showing signs of failure consistently displayed lesser ISQ. Statistically significant difference was observed in the scores of peri-implant indices of failure and no failure group of mini-implants. Conclusion: Mini-implants in thin gingival biotype are more susceptible to failure and peri-implantitis compared to thick gingival biotype. Longitudinal assessment of mini-implant stability may help predict failure so as to avoid long duration and cost of orthodontic treatment.

The Effect of Insertion Angle on Primary Stability of Orthodontic Mini-implants "An Experimental in vivo Study"

The Effect of Insertion Angle on Primary Stability of Orthodontic Mini-implants "An Experimental in vivo Study"

Effect of Photobiomodulation by 808nm Diode Laser on the Stability of Orthodontic Mini-implants.

Effect of Photobiomodulation by 808nm Diode Laser on the Stability of Orthodontic Mini-implants.

Long-term stability behavior of paramedian palatal mini-implants: A repeated cross-sectional study

The initial stability of orthodontic mini-implants is well investigated over a period of 6weeks. There is no clinical data available dealing with the long-term stability. The aim of this study was the assessment of long-term stability of paramedian palatal mini-implants in humans. Stability of 20 implants was measured after removal of the orthodontic appliance (sliding mechanics for sagittal molar movement 200cN each side) before explantation (T4) using resonance frequency analysis (RFA). Data were compared with a matched group of 21 mini-implants assessing the stability immediately after insertion, and after 2, 4, and 6weeks (T0-T3). The mini-implants used in this study were machined self-drilling titanium implants (2.0×9.0mm). Gingival thickness at the insertion site was 1-2mm. The implant stability quotient (ISQ) values before removal of the implant at T4 were 25.2±2.9 after 1.7±0.2years and did not show a statistically significant change over time compared with the initial healing group (T0-T3). Comparing the stability of mini-implants just after completion of the healing period and at the end of their respective usage period revealed no significant difference. An increase of secondary stability could not be detected. The level of stability seemed to be appropriate for orthodontic anchorage.

Low-Level Laser Therapy with a 635 nm Diode Laser Affects Orthodontic Mini-Implants Stability: A Randomized Clinical Split-Mouth Trial.

Background: The study aimed to clinically estimate an influence of a 635 nm diode laser on the stability of orthodontic mini-implants, to assess mini-implants loss, and to evaluate a pain level after the treatment. Materials and Methods: The randomized clinical split-mouth trial included 20 subjects (13 women and 7 men; age: 32.5 ± 6.1 years), 40 implants (RMO, West Colfax Ave., Denver, CO, USA) with a diameter 1.4 mm and length of 10 mm. Mini-implants were placed in the area of the attached gingiva between the second premolar and first molar teeth, 2 mm below the mucogingival junction of both sides of the maxilla. Each implant on the right side (G1, n = 20) of the maxilla was irradiated with a diode laser, and the implants on the opposite side (left, G2, n = 20) were a control group (without laser irradiation). The 635-nm laser parameters; dose: 10 J per point (20 J/cm2), time: 100 s per point, two points (irradiation on a buccal, and a palatal side of the alveolus/implant), the total energy per session 20 J. Laser application protocol: immediately and 3, 6, 9, 12, 15, and 30 days after surgery. The total energy after all therapeutic sessions was 140 J. The implants’ stability was measured employing a Periotest device (Periotest Test Value—PTV) immediately and 3, 6, 9, 12, 15, 30, and 60 days after the insertion of the mini-implants. Results: We found significantly higher secondary stability, lower mean PTV (6.18 ± 5.30) and (1.51 ± 2.25), for self-drilling mini-implants (G1, test group) in contrast to the control, G2 group (9.17 ± 8.25) and (5.00 ± 3.24), after 30 (p = 0.0003) and 60 days (p = 0.0000). Moreover, the analysis of the mini-implants stability after 635-nm diode laser application revealed significant higher stability in comparison with none irradiated implants (G2 group) after 3 days. (p = 0.0000) There was no significant difference in pain level measured on the NRS-11 scale on both sides of the maxilla. (p = 0.3665) An important finding was that all inserted mini-implants survived during a two-month observation period. Conclusions: 635-nm diode laser at laser irradiation increases the secondary stability of orthodontic mini-implants.

Predicting primary stability of orthodontic mini-implants, according to position, screw-size, and bone quality, in the maxilla of aged patients: a cadaveric study.

This study aimed to evaluate the effect of implant size and bone condition on primary stability of orthodontic mini-implants with a view to predict the primary stability before insertion. Four-hundred and forty mini-implants of two different diameters (2.0 and 2.3mm) and lengths (7 and 12mm) were inserted at 11 different positions in human cadaver maxillae. Before placement of mini-implants, cone beam computed tomography (CBCT) scans were performed to measure bone density and cortical thickness and, after mini-implant placement, implant stability quotient (ISQ) values were determined by resonance frequency analysis and cofactors were analyzed to determine their influence on the primary stability. Additionally, an equation was developed to predict the expected stability based on implant size and bone quality. Bone density varied between 433(SD122) and 587(SD249) Hounsfield units (HU), and cortical thickness varied between 0.49(SD0.42) and 0.98(SD0.60)mm. The lowest ISQ value, of 15.50(SD7.29) (bone density: 531 (SD219) HU; cortical thickness: 0.65(SD0.58)mm), was found for a mini-implant of 2.0×7mm and the highest ISQ value, of 46.30(SD8.69) (bone density: 587(SD249) HU; cortical thickness: 0.98(SD0.60)mm), was found for a mini-implant of 2.3×11mm. Statistically significant influences of the cofactors on primary stability were demonstrated. To visualize the predictive power of the model, the observed values versus the predicted values of primary stability were compared and the model fit was represented by residual plots. The expected primary stability can be estimated by a linear regression model comprising the radiologically determined bone density, cortical thickness, implant length and diameter, and placement position.

Effects of cortical bone thickness and trabecular bone density on primary stability of orthodontic mini-implants

Background/purposeMini-implant screws are now routinely used as anchorage devices in orthodontic treatments. This study used synthetic bone models to investigate how the primary stability of an orthodontic mini-implant (OMI) as measured by resonance frequency (RF) is affected by varying cortical bone thickness and trabecular bone density. Materials and methodsThree synthetic cortical shells (thicknesses of 1, 2, and 3 mm) and three polyurethane foam blocks (densities of 40, 20, and 10 pound/cubic foot) were used to represent jawbones of varying cortical bone thicknesses and varying trabecular bone densities. Twenty-five stainless steel OMIs (2 × 10 mm) were sequentially inserted into artificial bone blocks to depths of 2, 4, and 6 mm. Five experimental groups of bone blocks with OMIs were examined by Implomates® RF analyzer. Statistical and correlation analyses were performed by Kruskal-Wallis test, Wilcoxon rank-sum test, and simple linear regression. ResultsAs trabecular bone density decreased, RF decreased; as cortical bone thickness decreased, RF also decreased. Simple linear regression analysis showed highly linear correlations between trabecular bone density and RF (R2 > 0.99; P < 0.0001) and between cortical bone thickness and RF (R2 > 0.98; P < 0.0001). ConclusionThe stability of an OMI at the time of placement is influenced by both cortical bone thickness and trabecular bone density. Both cortical bone thickness and trabecular bone density have strong linear correlations with RF.

Effect of insertion angle on the stability of orthodontic mini-implants in a rabbit tibia model: A finite element analysis.

Mini-implants are an alternative to traditional methods of anchorage in orthodontic treatment. However, there are still questions concerning their application, in particular, with the insertion angle. To determine whether the angle of insertion of the mini-implant is a determining factor in their primary stability when they support orthodontic loads. A finite element model (FEM) of tibia bone, spring and mini-implant was developed. The three-dimensional model of the rabbit tibia was constructed based on tomographic slices. The angles that were analyzed were 90°, 80°, 70°, 60°, 50°, 45°, 40°, and 30°. A horizontal force of 2 N applied to the head of the mini-implants was simulated. The von Mises stresses and displacements were determined using FEM. Von Mises stresses were lower for an insertion angle of 40° followed by 90° and 70°; likewise, the displacements of the mini-implants with respect to the spring were lower for the 40° angle followed by 90° and 70°, we found a statistically significant association between the insertion angle and displacement. All mini-implants underwent a degree of angulation and displacement; however, mini-implants inserted to the bone surface at 40° tend to have better primary stability, and they can withstand loads immediately.

Investigation of the optimal design of orthodontic mini-implants based on the primary stability: A finite element analysis.

Background. The design of an orthodontic mini-implant is a significant factor in determining its primary stability and its clinical success. The aim of this study was to measure the relative effect of mini-implant design factors on primary stability of orthodontic mini-implants. Methods. Thirty-two 3-dimensional assemblies of mini-implant models with their surrounding bone were generated using finite element analysis software. The maximum displacement of each mini-implant model was measured as they were loaded with a 2-N horizontal force. Employing Taguchi’s design of experiments as a statistical method, the contribution of each design factor to primary stability was calculated. As a result of the great effect of the upper diameter and length, to better detect the impact of the remaining design factors, another set of 25 models with a fixed amount of length and diameter was generated and evaluated. Results. The diameter and length showed a great impact on the primary stability in the first set of experiments (P<0.05). According to the second set of experiments, increased taper angle in the threaded and non-threaded area decreased the primary stability. There was also an optimum amount of 2.5 mm for threaded taper length beyond which the primary stability decreased. Conclusion. It is advisable to increase the diameter and length if primary stability is at risk. In the second place, a minimum amount of taper angle, both in the threaded and non-threaded area with an approximate proportion of 20% of threaded taper length to MI length, would be desirable for MIs with a moderate size.

A novel technique for measurement of orthodontic mini-implant stability using the Osstell ISQ device.

To develop and validate a method for application of the Osstell ISQ device in the assessment of mini-implant stability. An adaptor was developed for attachment of Osstell's SmartPeg onto a variety of orthodontic mini-implants. For validation of the adaptor, Benefit mini-implants were inserted into bone blocks that mimicked different stability conditions. The Osstell device was used to assess mini-implant stability with the adaptor (test measurement) and conventional SmartPeg attachment (gold-standard measurement). Implant stability quotient (ISQ) values were assessed for agreement, repeatability, and reproducibility. Strong positive correlations were found between ISQ values obtained using the novel adaptor and the conventional attachment. Repeatability and reproducibility of ISQ values with the adaptor were similar to those obtained with the conventional attachment. A method was developed and validated to assess the stability of orthodontic mini-implants using the Osstell system. The novel mini-implant adaptor provided repeatable and reproducible measurements of mini-implant stability, which agreed with those obtained using a conventional SmartPeg attachment. This adaptor permits noninvasive stability assessment of various designs of mini-implants, most of which are incompatible with the conventional SmartPeg attachment.

Measurement of Primary Stability of Mini Implants Using Resonance Frequency Analysis

Introduction In the last decade, anchorage control with mini-implants has gained enormous credibility in maintaining orthodontic anchorage. Resonance frequency analysis (RFA) has proven to be an adequate method to measure the stability of these mini-implants because of its non-invasiveness and contactless measurement method. Materials and Method Tomas and S.K surgical mini-implants were tested. For this purpose custom fabricated attachment was fabricated to attach the smart peg on orthodontic mini-implant head, and 45 mini-implants were inserted in fresh swine pelvic bone in the density matched sites to that of most common sites where mini-implants are placed in human mandible. Mini-implants of two different lengths with diameter constant were also placed to assess the effect of length on primary stability. Results The mean ISQ of Group 1 (Tomas 10 mm) was 55.53±3.39 while that of Group 2 (S.K Surgical 10mm) was 56.63±3.48 and that of Group 3(S.K Surgical 8 mm) was 55.90±3.48. Difference among the groups were not statistically significant when ANOVA test was used (P &gt;0.05). Conclusion The resonance frequency analysis is applicable to comparatively assess the primary stability of orthodontic mini-implants. There was no difference in primary stability of Tomas and S.K Surgical mini-implant and primary stability was not affected by the length of the mini-implant.

Effects of low-intensity laser therapy on the stability of orthodontic mini-implants: a randomised controlled clinical trial.

To investigate the effect of low-intensity laser therapy on mini-implant stability using resonance frequency analysis during canine retraction with fixed appliances. A split-mouth randomised clinical trial. Subjects were recruited and treated in the outpatient clinic, Department of Orthodontics, Faculty of Dentistry, Cairo University. Fifteen subjects with mean age 20.9 (±3.4) years who required extraction of maxillary first premolar teeth and mini-implant-supported canine retraction. Thirty orthodontic mini-implants were inserted bilaterally in the maxillary arches of recruited subjects following alignment and levelling. Mini-implants were immediately loaded with a force of 150 g using nickel titanium coil springs with split-mouth randomisation to a low-intensity laser-treated side and control side. The experimental sides were exposed to low-intensity laser therapy from a diode laser with a wavelength of 940 nm at (0, 7, 14, 21 days) after mini-implant placement. Mini-implant stability was measured using resonance frequency analysis at (0, 1, 2, 3, 4, 6, 8, 10 weeks) after implant placement. A total sample of 28 mini-implants were investigated with 14 in each group. Clinically, both mini-implant groups had the same overall success rate of 78.5%. There were no significant differences in resonance frequency scores between low-intensity laser and control sides from baseline to week 2. However, from week 3 to 10, the low-intensity laser sides showed significantly increased mean resonance frequency values compared to control (P > 0.05). Despite evidence of some significant differences in resonance frequency between mini-implants exposed to low-intensity laser light over a 10 weeks period there were no differences in mini-implant stability. Low-intensity laser light cannot be recommended as a clinically useful adjunct to promoting mini-implant stability during canine retraction.