Mini Implants Research Articles

Anchorage and Stability of Orthodontic Mini Implants in Relation to Length and Types of Implants

Anchorage and Stability of Orthodontic Mini Implants in Relation to Length and Types of Implants

A comparative evaluation of cytotoxicity and corrosion resistance between titanium and stainless steel orthodontic mini implants: An in vitro study

A comparative evaluation of cytotoxicity and corrosion resistance between titanium and stainless steel orthodontic mini implants: An in vitro study

Automatic Segmentation of the Jaws Used in Guided Insertion of Orthodontic Mini Implants to Improve Their Stability and Precision.

Background and Objectives: With the goal of identifying regions with bicortical bone and avoiding root contact, the present study proposes an innovative technique for the simulation of the insertion of mini orthodontic implants using automatic jaw segmentation. The simulation of mini implants takes place in 3D rendering visualization instead of Multi-Planar Reconstruction (MPR) sections. Materials and Methods: The procedure involves utilizing software that automatically segments the jaw, teeth, and implants, ensuring their visibility in 3D rendering images. These segmented files are utilized as study models to determine the optimum location for simulating orthodontic implants, in particular locations characterized by limited distances between the implant and the roots, as well as locations where the bicortical structures are present. Results: By using this method, we were able to simulate the insertion of mini implants in the maxilla by applying two cumulative requirements: the implant tip needs to be positioned in a bicortical area, and it needs to be situated more than 0.6 mm away from the neighboring teeth's roots along all of their axes. Additionally, it is possible to replicate the positioning of the mini implant in order to distalize the molars in the mandible while avoiding the mandibular canal and the path of molar migration. Conclusions: The utilization of automated segmentation and visualization techniques in 3D rendering enhances safety measures during the simulation and insertion of orthodontic mini implants, increasing the insertion precision and providing an advantage in the identification of bicortical structures, increasing their stability.

Effects of mini-implant anchorage on mandibular rotation and esthetic outcomes in hyperdivergent skeletal Class II malocclusion treatment

Objectives: This research aimed to investigate the effects of mini-implants (MIs) on mandibular position and changes in lower face height, as well as their relationship with the position of the maxillary molars and incisors in the camouflage treatment of patients with hyperdivergent skeletal Class II malocclusion. Material and Methods: This retrospective study included 27 patients aged 15–38 years. The hyperdivergent patients were diagnosed with skeletal Class II malocclusion and treated with tooth compensation, tooth extraction, posterior repositioning of the maxillary incisors, and anchoring with MIs. Cephalometric analyses of these patients were performed before (T1) and after (T2) treatment. Measurements were taken at each treatment stage and analyzed. Results: Significant correlations were observed in the mandibular position and lower face height (P < 0.05). The GoGnSN angle decreased (−1.05 ± 1.61°), the ANS-Me distance reduced (−1.98 ± 4.76 mm), and the NBaPtGn angle increased (1.67 ± 4.08°). In addition, the vertical height position of the maxillary first molar significantly decreased (6M-FH, −1.61 ± 3.74 mm), while the vertical height position of the maxillary incisor increased (U1-FH, 1.48 ± 2.11 mm). Conclusion: During the camouflaging treatment of patients with hyperdivergent skeletal Class II malocclusion using MIs anchorage, MIs helped intrude the maxillary first molar and extrude the maxillary incisor, leading to a difference in a mandibular counterclockwise rotation. Controlling the rotation of the lower jawbone helps create an improved esthetic for the patient after treatment.

Mandibular overdenture retained by four one-piece titanium-zirconium mini implants: A 2-year RCT on patient-reported outcomes

AimThe positive impact of implant interventions on dental patient-reported outcomes is an essential parameter of treatment effectiveness. This study assessed the 2-year changes in patient satisfaction and oral health-related quality of life (OHRQoL) of edentulous patients treated with a four mini implant mandibular overdenture (IOD) MethodsThe study was planned as a 2 × 2 factorial randomized clinical trial that tested two surgical approaches (flapped or flapless) and two loading protocols (immediate and delayed) using a titanium-zirconium mini implant (Straumann Mini Implant System®) and a PEEK retentive system (Straumann® Optiloc® Retentive System). Outcome measures (OHIP-Edent scores and the McGill Denture Satisfaction questionnaire) were assessed before treatment and at the 3-, 6-, 12-, and 24-month follow-ups. The Friedman test and multiple regression using Generalized Estimating Equations (GEE) were used for data analysis, considering the per-protocol (PP) and intention-to-treat (ITT) approaches ResultsSeventy-four patients were randomized to the study groups. No implant failure occurred during the study period. Marked improvement in all post-treatment periods compared to baseline were observed for the two outcomes. No significant effect of patient's gender, age, and surgical protocol on the study outcomes. The effect of treatment provision was significant for the two outcomes in the PP and ITT approaches (p < 0.001). A barely significant positive effect of the immediate loading was observed for OHIP-Edent in the PP approach (p = 0.020) ConclusionIOD treatment significantly improved patient-reported outcomes measures, with sustained benefits over the two years of overdenture use, and can be considered a promising treatment option in for the edentulous mandible.

Mandibular overdenture retained by four one-piece titanium-zirconium mini implants: A 2-year follow-up on prosthodontic outcomes

ObjectiveThis 2-year prospective study reports the incidence of prosthetic complications and maintenance events after treatment with mandibular overdenture retained by four mini implants opposed to a maxillary denture. MethodsImplant intervention included flapless or flapped surgery combined with immediate or delayed loading, as part of a randomized clinical trial. Four one-piece titanium-zirconium mini-implants (Straumann Mini Implant System) were inserted, and the retentive PEEK elements (Optiloc) were incorporated into the overdenture using chairside procedures. Prosthodontic complications and maintenance events were recorded over a 2-year follow-up, and the final outcome was defined according to standardized criteria. Data analysis included descriptive statistics, incidence and incidence density rates, and Kaplan-Meier survival. Results73 out of 74 patients (64.9 % female), mean age of 64 (SD=8.2) years, completed the study follow-up (one withdrew after 9 months). Implant survival was 100 %. A total of 163 prosthodontic events occurred in 53 patients (72.6 %), and 20 patients had no clinical complaints or maintenance needs. The most common procedures were adjustment/repair of the overdenture base (47.0 %), replacement of retentive inserts (19.8 %), and laboratory relining (12.9 %). A high prosthodontic success rate was achieved (93.2 %), and all patients presented serviceable overdentures and continuous use after the resolution of prosthodontic complications. The incidences of matrix replacement and laboratory relines were low in the first year, while denture base adjustments were common within the first year, especially in the first 6 months. ConclusionThe mini implant system showed high prosthodontic success rates. Minor adjustments/repairs during the initial follow-up were common. Relines and matrix replacements tend to occur after one year of overdenture use, and matrix replacements may occur as a consequence of the need for relining.

Accessories in clear aligner therapy: Laypeople's expectations for comfort and satisfaction.

This study explored the layperson's perception of comfort, satisfaction, and willingness to use various accessories in clear aligner therapy. A total of 267 people analyzed standardized intraoral photographs of a female model in orthodontic treatment using: 1) only clear aligner (CA), the control group; 2) clear aligner+attachments (AT); 3) clear aligners+Cl II elastics (EL); 4) clear aligner+hybrid treatment with esthetic braces (HEB); 5) Clear aligner+hybrid treatment with metallic braces (HMB); 6) clear aligner+mini-implants (MI); 7) clear aligner+mini-implants and elastics for intrusion (MIE). In addition, a social media questionnaire was distributed to assess the willingness to undergo orthodontic treatment with various accessories. There was a significant difference between CA and all the other groups (P<0.001), with CA being considered more comfortable and providing greater satisfaction compared to other accessories. Moreover, AT showed a significant difference in reducing treatment time compared to other groups. The CA was the most comfortable, exhibiting a higher satisfaction rate and a greater willingness to use it. The AT therapy was perceived as more comfortable and was associated with higher satisfaction and a greater likelihood of use, especially if it resulted in reduced treatment time. On the other hand, the participants reported that the HMB, MI, and MIE accessories were less comfortable.

A finite element method study to compare enmasse retraction of maxillary anteriors using mini implant and conventional anchorage method

Increased upper lip procumbency is associated with protrusive maxillary dentition in Angle’s class I malocclusion, creating unaesthetic facial profile, leading to the need of orthodontic treatment where Enmasse retraction will require maximum anchorage.The present study was conducted to compare Enmasse retraction of maxillary anteriors using mini implant and conventional anchorage in Angle’s Class I malocclusion with bimaxillary protrusion. A numeric approach was adopted. Finite element method was used to determine the stress and displacement of various components at a given time by dividing it into two groups namely, Implant arrangement and T- loop arrangement for enmasse retraction. Significant differences were observed when the stress values were compared between Implant arrangement and T-loop arrangement. In Implant arrangement highest stress values were seen around the lateral incisors and in T loop arrangement stresses were found around canine and premolar. Comparison of displacement in both arrangements gave results of greater displacement in anterior and posterior segments in T-loop arrangement. Mini implants were considered more effective for enmasse retraction but in this study, it was found that although the rate of retraction/ displacement was more in T-loop arrangement but Mini implants in implant arrangement served as an absolute anchorage.

Comparative evaluation of accuracy and stability of Orthodontic temporary anchorage device with and without the use of Mini-implant placement guiding device (MIG-20) in adults- An in vivo study

Mini implants have been researched extensively in terms of their efficiency, material used, and methods of accurate placement. When properly used,they might be a substitute method of anchorage preparation as compared toconventional molar anchorage and might reach alike or even superior results in certaincases.The present study aimed to evaluate and compare accuracy and stability of orthodontic temporary anchorage device with and without the use of Mini-implantplacement guiding device (MIG-20) in adults.Each patient underwent implant placement using both methods to have a similar oral environment for groups. Each case was treated in a split-mouth pattern to eliminateselection bias (to have the same baseline characteristics for both groups). Sideselection for that particular method was undertaken by using computer-generatedrandomization. So in all 2 groups were categorized. Mini-implant inserted by theconventional method (Control Group). Group II: Mini- Implant inserted by using MIG-20. Mini-implants were placed on both sides of the maxillary jaw between the 1 st molarand 2 nd premolar with the self-drilling manual method. Evaluation of clinical pictures, pre and post RVG and stability/mobility were done for each sample in both groupsusing AutoCAD software 2013.Out of 21 cases in Control group, it was observed that100% of cases in Control group had a vertically deviated mini-implant, which was statistically significant as compared to Study group, where 28.57% (6) cases demonstrated vertical deviation and 71.43 % (15) cases, where no deviation of miniimplantwas seen in vertical dimension when observed clinically. (p=0.0001, S). In71.43 % of cases, no significant variation was observed clinically in Study Group inmesiodistal dimension. (p=0.0001, S).The findings of the study substantiate the effectiveness of the 3-D Mini-Implant placement guide (MIG-20) when compared to the conventional method, inachieving a more accurate mesiodistal and vertical placement of mini implants.

Two simple yet efficient biomechanics for correction of retroclined maxillary central incisors

Angle’s class II division 2 malocclusion is characterized by retroclined maxillary central incisors and increased overbite. The first step in the treatment of such cases involves the correction of incisor inclination and their intrusion. Conventional techniques for intrusion are taxing on the anchor teeth like molars and adjacent teeth like lateral incisors. Appropriate biomechanical use of temporary anchorage devices (TADS) will enable the clinician to avoid undesirable tooth movements. The following are two cases in which simple and efficient biomechanics have been performed with the use of TADS for the correction of incisor inclination and deep overbite. The case-specific use of single vs two mini implants as well as round vs rectangular wire for intrusion and proclination of central incisors has also been explained.

Changes in masticatory performance and bite force after treatment with mandibular overdentures retained by four titanium-zirconium mini implants: One-year randomised clinical trial.

This prospective study is part of a randomised clinical trial and reports the changes in masticatory performance (MP) and bite force, and explores their influential factors, 1 year after the provision of mandibular overdentures retained by four titanium-zirconium mini implants. Edentulous patients received conventional complete dentures, followed by placement of four mini implants (Straumann® Mini Implant System) in the anterior mandible and converting the conventional prosthesis into a mandibular overdenture. Treatment protocols were randomised using a 2×2 factorial design combining different surgical (flapped vs. flapless) and loading (immediate vs. delayed) protocols. MP was assessed using a two-colour mixing ability test and a colorimetric analysis to measure the level of colour mixing (Variance of Hue-VoH). Maximum voluntary bite force (MBF) was measured by a digital gnathodynamometer in the posterior and anterior regions. Sex, age, surgical and loading protocols and ridge morphology were tested as independent variables. MP and MBF tests were performed at baseline (pre-treatment) and the 3-, 6- and 12-month after implant loading. Descriptive statistics, independent t-test, and linear mixed-effect model (LMM) regression were used for data analysis. Seventy-four participants were assessed and 73 completed the 1-year follow-up. Statistically significant improvements in functional parameters were observed in all follow-up periods compared to baseline (p < .001). The flapless protocol was associated with higher improvement in MP at the 3-month follow-up (p = .004), while less resorbed ridges were associated with better MP (p = .038) and higher MBF (p < .001). The mandibular overdenture protocol using four titanium-zirconium mini implants was effective in improving MP and MBF of edentulous patients, compared to pre-treatment values. The findings also suggest that improvements in chewing function and bite force are impacted by clinical factors since better outcomes were observed for flapless surgeries and less resorbed edentulous ridges. ClinicalTrials.Gov ID NCT04760457.

Unilateral mesialisation using Temporary anchorage device and segmental T loop – A case report

A temporary anchorage device is a device that is temporarily fixed to bone for the purpose of enhancing orthodontic anchorage either by supporting the teeth of the reactive unit or by obviating the need for the reactive unit altogether, and which is subsequently removed after use. Use of mini implants is one of the innovative approach for complex tooth movements such as mesialisation. Space closure from distal to mesial is one of the most difficult orthodontic tasks. Tooth-borne anchorage limits the scale of tooth movement. Extraoral or intraoral appliances are used especially for unilateral space closure. As an alternative to conventional mesialization appliances, osseointegrated implants may be used for maximum anchorage in orthodontic treatment. The use of direct anchorage in the form of installed mini-implant that is connected to the teeth requiring horizontal movement causes low levels of strains on anchor unit comparing to the results that were registered during indirect anchorage with one or two anchor teeth. This report presents the case of removal of mesiodens and blocked out and fractured premolar and the space closure by unilateral mesialisation with the help of mini implants and loops.

Ridge split assisted molar protraction

Protraction of a second molar into the gap left by a missing first molar is an option, although it is challenging to maintain root parallelism during mesial migration due to the thick and dense cortical bone. This study was carried out to make an attempt to evaluate whether molar protraction in subjects with missing mandibular first molar and knife edge ridges is possible or not using ridge split procedure (expansion).The sample consisted of 12 subjects with missing mandibular first molar and knife edge ridges. All pre-treatment records were taken, after initial leveling and alignment ridge split procedure was performed and molar protraction was carried out using mini implants. Data was collected at a fixed interval of every six weeks. Statistical analysis using Repeated-measures ANOVA and Paired t test were done for evaluation of the rate of molar protraction and mesial molar tipping 0.12mm per week and 0.9 mm per six weeks was the rate of molar protraction that was accomplished. The mean edentulous space decreased from pre protraction to third visit significantly with a p value of ≤ 0.001.There is mesial tipping of molar post protraction with a P value of 0.148 which is statistically non-significant. On an average duration for molar protraction was 8.4 months.Ridge split made molar protraction possible in subjects with missing mandibular molar and knife edge ridges and enhanced the rate of tooth movement. The absolute anterior dental anchorage for the desired orthodontic movement was achieved by utilisation of mini implants.

Effect of Different Mini Implant Assisted Rapid Palatal Expansion (MARPE) Designs on Maxillary Protraction in Skeletal Class III malocclusion: An FEM Study.

Four different designs of mini-implant-assisted rapid palatal expansion (MARPE) and protraction in nasomaxillary complex and mid-palatal sutures in late adolescent skeletal Class III malocclusion were compared using a three-dimensional finite element analysis. A finite element model of skull and related sutures was constructed using the computed tomography scan of a 16-year-old female patient with skeletal Class III and ANB of -2°. Four appliance designs: Type I: MARPE with palatal force, Type II: MARPE with buccal force, Type III: Hybrid hyrax with palatal force, and Type IV: Hybrid hyrax with buccal force. Protraction vectors were and analyzed using Ansys software (ANSYS 2021 R2). The displacement pattern of the nasomaxillary structures and the stress distribution in the sutures were examined in all four appliance designs. All the appliance designs resulted in a forward movement of the maxilla, while Type I and III, which used palatal protraction force, caused the greatest forward displacement. In Type I, II, and III, along with forward movement, a clockwise rotation of maxilla was observed, while in Type IV, an anticlockwise rotation of maxilla was observed. Type I, II, and III resulted in higher stress distribution around the superior structures, while Type IV resulted in less stress distribution around the superior structures of maxilla. The forward displacement was enhanced when palatal plates were used to protract the maxilla. The effective appliance design for skeletal class III with open bite case was Type I, II, and III and Type IV for deep bite cases.

Dimensiones tomográficas para la instalación de miniimplantes de expansión rápida maxilar en diferentes grupos de edad

Objective: The purpose of the research was to com-pare the dimensions of the upper jaw between different age groups for the installation of mini-implants for rapid maxillary expansion. Materials and Methods: The study was descriptive, retroprospective and observational. Cone beam computed tomography was used for the evaluation of 30 patients between 7 and 56 years of age, divided into three groups, ten up to 14 years, ten from 15 to 30 years, and ten from 31 years and older. The premolar and molar regions were selected for the measurement of the maxilla in the coronal plane, both bone and soft tissue. To compare the measurements, the Kruskal Wallis and Mann-Whitney U tests were used. Results: No statistically significant differences were found between the groups. The thicknesses of the bone tissue decreased from the first premolar to the second molar from 9.48 +/-3.71 mm to 5.40 +/-2.80 mm respectively, while the soft tissue thicknesses were more homogeneous with measurements of 0.56 +/-0.74 mm to 2.76 +/- 2.42 mm. Conclusions: The dimensions of the bone and soft tis-sue of the upper jaw, evaluated vertically for the installa-tion of mini-implants, were similar in all the age groups studied, with larger dimensions in men than in women at the premolar level. The dimensions of the maxilla for the palatal miniimplants were close to 9 mm in bone tissue and 3 mm of soft tissue at the level of premolars and 5 mm in hard tissue with 1 mm of soft tissue at the level of molars. Keywords: Palatal expansion technique; Dental im-plants; Mini implants; Maxilla; Cone-beam computed to-mography; Age groups

Stability of Mini Implants in the Periodontum during Orthodontic Treatment

Stability of Mini Implants in the Periodontum during Orthodontic Treatment

Evaluation of stress in bone by 9 different mini implants based on placement angle with relation to enmasse retraction force - An FEM study

The aim of this study was to evaluate the stress in bone at the mini implant site, placed at 5 different insertion angles with relation to en-mass retraction force using a Finite element analysis. Evaluation of stress in bone and their distribution pattern at the mini implants. Evaluation of stress distribution in surrounding cortical bone on application of retraction force at 5 different insertion angle. Force applied was 200 grams on the model. The mini implants were modelled with varying diameters (1.3mm, 1.6mm, and 2.3mm) and varying lengths (7mm, 8mm, 10mm). The implant insertion angulations used were 30°, 45°, 60°, 90°, 120°.The pitch of the implant thread used was 0.5mm. This was fixed in all implant designs in this study. After the models were created, a process called meshing in which the models were divided individually into a finite number of elements,. The model was meshed with a tetrahedral configuration. The complete geometry has an assembly of discrete pieces called elements and is connected to gather at a finite number of points called nodes.In bone Von Mises stress was high in 1.3 × 8 mm implant at 60angulation and least was in 2.3 × 7 mm implant at 30angulation. In Implant of 1.3 × 10 mm in 90angulation showed high Von Mises stress and in Implant of 2.3 × 8 mm in 30angulation showed least Von Mises stress.Mini implant which has got smaller diameter, long length and high inclination angle showed higher stresses when compared to other mini implants.

The intra- and inter-rater reproducibility of bone level measurements at strategic mini-implants using dental panoramic radiography

ObjectivesThis experimental study focused on the intra- and inter-rater reproducibility of vertical bone level (VBL) measurements at strategic mini-implants (MI) using digital panoramic radiographs (PR). Study designVBLs of 152 MIs for removable partial denture stabilization at 50 randomly chosen PRs from a clinical trial were digitally evaluated by three ratters. Rater deviations exceeding 0.5 mm were re-examined. The intra-class correlation coefficient (ICC) was applied to estimate reliability. The smallest detectable change (SDC) was interrelated to the minimal clinically important change of 0.2 mm. ResultsThe first measurement round revealed intra- and inter-rater ICCs of > 0.8. However, 28 sites (9 %) were unreadable, and 97 sites (32 %) revealed differences between observers of ≥ 0.5 mm. Following a consensus session and re-training, an additional 8 sites were excluded and all remaining VBL differences were ≤ 0.5 mm. Thus, the SDCs with 95 % credibility were improved from 0.73 to 0.31 mm in the intra-rater and from 1.52 to 0.34 mm in the inter-rater statistics. Given a 50 % credibility for this special setting, both the intra- and inter-rater SDCs were 0.11 mm. ConclusionsDigital PR can be reliably utilized to determine VBLs around MIs under conditions of at least two trained observers, mutual calibration sessions, and exclusion of unquantifiable radiographs. German Clinical Trials Register IDDRKS00007589, www.germanctr.de

CONTRIBUTION OF CORRECTIVE ORTHODONTICS PRIOR TO PROSTHETIC REHABILITATIVE TREATMENT: literature review

Today's dentistry has increasingly sought treatments that involve a multidisciplinary approach to specialties. Therefore, orthodontics is the branch that deals with the prevention and correction of occlusal problems, acting in many cases in the pre-prosthetic treatment of patients. For this, the most used movements are, in general, extrusion, intrusion and verticalization. Thus, the justifications for this research consist of bringing updated information through a literature review, on the importance of multidisciplinary treatment in the rehabilitation of partially edentulous patients, with removable partial dentures, fixed prostheses or dental implants, correlating pre-prosthetic treatment with orthodontics. corrective. To this end, the general objective is to discuss the role of orthodontics in establishing a stable occlusion in patients who will undergo prosthetic rehabilitation. Specifically defining the advantages of orthodontics as an integral part of rehabilitative treatment, explaining the principles of malocclusion in partially edentulous patients. It is concluded, therefore, that there is a constant improvement in techniques and the possibility of success in the treatment of each patient. Intensive studies on mini implants are a factor of great importance in resolving cases requiring orthodontic adjustment. Therefore, orthodontic maneuvers, when planned before the prosthesis, can provide better hygiene, less plaque retention, elimination of unnecessary wear, correction of the occlusal relationship, distribution of occlusal forces, greater preservation of dental structures and better periodontal condition.

Stress distribution of four implant supported overdentures with tilted standard-sized implants and mini implants.

The goal of the current study is to evaluate the stress distribution when tilted implants and mini-implants are used to support a mandibular overdenture. Three-dimensional (3D) finite element models of mandibular overdentures were established using four, axial, standard-sized implants (SA model), four standard-sized implants with the mesial ones axial and the distal ones tilted (ST model) and four mini-implants (MA model) with Locator attachments. On each model, a 100 N load was applied to the overdenture in four different directions; bilateral vertical, unilateral vertical and oblique load on the posterior region, and a vertical load on the incisors. The stresses distributed at the peri-implant bone, implants, the prosthetic components, and the overdentures were evaluated. Non-axial posterior loading caused higher stress values in the implant and the prosthetic component than axial posterior loading. Lower stress values of the implant and the prosthetic component were observed in the ST model than SA model. The stress distribution in the overdenture at posterior loads were mostly observed around the implants. Less prosthetic complications may be expected when the treatment option in the ST model is used. Fatigue fractures may occur around the implants in the overdentures, precautions are advised.