Orthodontic Mini-implants Research Articles

SIMULTANEOUS RETRACTION AND INTRUSION OF MAXILLARY ANTERIOR TEETH: A REVIEW

Simultaneous retraction and intrusion of anterior segment are required in the patients who have deep overbite along with ared incisors. During the retraction of anterior segment, there is some bite deepening, which also requires intrusion. So there are various conventional methods which are used from many last years to achieve simultaneous retraction and intrusion, but these methods require patient compliance and have some undesirable side effects like anchorage loss. With the advent in technology, Orthodontic mini-implants (OMI) broaden the scope of orthodontic therapy by allowing treatment to proceed with little or no anchoring loss and require less patient participation than traditional procedures. Mini implants can be used to offer good anchorage for anterior tooth retraction and intrusion, and they can be inserted in almost any desirable site. There are various conventional methods as well as mini implant supported methods with which simultaneous retraction and intrusion can be achieved. This review article presents the various methods for achieving simultaneous retraction and intrusion of anterior segment either with conventional techniques or with the help of mini implants.

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.

Assessment of outcome of orthodontic mini dental implants

Background: Successful orthodontic therapy has always depended upon on intraoral anchorage with a great resistance to displacement. Osseointegrated implants are considered reliable sources of anchorage for orthodontists hence; the present study was undertaken for assessing the outcome of orthodontic Mini dental implants. Materials & methods: A total of 100 patients were enrolled. In all the involved patients, one or more self-drilling mini-screws were inserted. Orthodontic mini-implants were considered successful when they proved a perfect skeletal anchorage during the entire treatment period (independent from the period's length) without sign of mobility. All the results were recorded and analysed using SPSS software. Results: Success was observed in 85 percent of the cases. Failure was seen in 15 percent of the cases. Among the failure cases, inflammation was the cause in 10 percent of the cases while screw fracture was seen in 5 percent of the cases. Conclusion: Under the hands of skilled and experienced clinician, self-drilling orthodontic mini-implants had excellent prognosis.

Accuracy of Sterile and Non-Sterile CAD/CAM Insertion Guides for Orthodontic Mini-Implants

AimThe aim of this study was to measure the transfer accuracy of computer-aided design/computer-aided manufacturing (CAD/CAM) insertion guides using mini-implants. The target value is the virtual planned position (100%). It is also clinically mandatory to use sterilised surgical guides (autoclaved at 137°C). The results obtained using sterilised and non-sterilised insertion guides were compared. In addition, the actual position of the mini-implants, as implemented, was compared with the digitally planned positions.Materials and MethodsFollowing CAD/CAM planning and production of 60 insertion guides made from synthetic resins that had been previously tested for suitability, 120 mini-implants were inserted in pairs and in blocks of the bone of the substitute material. Half of the insertion guides were sterilised, while the other half were non-sterilised. Compared with the position of the mini-implants in the digital plans, deviations in the apical and coronal distances between the mini-implants and insertion depth, as well as the included angle of the mini-implants to one another and to the surface of the bone substitute material, were determined.ResultsIn post-sterilisation, the dimensional and material changes were observed. When compared, the deviations to the virtual planned position were achieved when the performed insertion using sterilised insertion guides were lower than those achieved when using non-sterilised insertion guides. The heat treatment during the sterilisation process improved the accuracy of the insertion guides. When comparing sterile insertion guides to the digital planned position (100%), the mean coronal deviation was 0.057 mm (0.81%), the apical deviation was 0.428 mm (6.11%), and insertion depth mean deviation at the right side was 0.15 mm (2.15%), while that on the left was 0.073 mm (1.04%).ConclusionThe CAD/CAM TAD insertion guide could not achieve 100% accuracy in translating the digitally planned position into the real anatomic location. Deviations to the ideal position between 0.81 and 6.11% were observed. Clinically, for appliances that fit post-mini-implant insertion, the coronal distance of the mid-mini-implant head is the most important. At this point, the mean deviation to the planned positions is 0.81%, which is clinically acceptable and most likely reproducible by using CAD/CAM insertion guides.

Comparison of antimicrobial effect of selenium nanoparticles and silver nanoparticles coated orthodontic mini-implants – An in vitro study

Objectives: Mini-implants have earned a significant role in orthodontic treatment, by augmenting anchorage requirements. Peri-implantitis contributes to miniscrew failures where progressive peri-implant bone loss occurs in conjunction with soft-tissue inflammation due to the growth of microorganisms such as Streptococcus and Lactobacillus. Nanoparticles have increased surface area and have increased interactions with biological targets like bacteria. This study aims to investigate the antimicrobial activity of silver nanoparticles (AgNP) and selenium nanoparticles (SeNPs) on orthodontic mini-implants. Material and Methods: Mini-implant (Ti-6Al-4V) was coated with AgNP and SeNP with biopolymer (Ti-BPAgNP and Ti-BPSeNP) by dip-coating technique. The crystal structure and crystallite size of AgNPs and SeNPs were characterized by the X-ray diffraction (XRD) method. The size distribution and morphology of SeNP and AgNP were determined by a scanning electron microscope (SEM). The antibacterial activity of Ti-BP-AgNP and Ti-BPSeNP was detected from the zone of inhibition by disk diffusion assay. Results: The SEM image of AgNP was roughly spherical, uniformly distributed and SeNPs were spherical, well distributed on the biopolymer surface. The area of the zone of inhibition of Ti-BP-SeNP-coated mini-implants shows a negligible difference in antibacterial activity compared to Ti-BPAgNP-coated mini-implants. Conclusion: Ti-BP-AgNP and Ti-BP-SeNP showed that a strong antibacterial activity was against Lactobacillus and Staphylococcus aureus. Antibacterial activity against Streptococcus mutans was slightly less than observed in other bacteria. SeNP shows only a marginal difference in antibacterial activity when compared to AgNP.

Evaluation of Optimal Sites for the Insertion of Orthodontic Mini Implants at Mandibular Symphysis Region through Cone-Beam Computed Tomography.

This study aims to evaluate the overall bone thickness (OBT) and cortical bone thickness (CBT) of mandibular symphysis and to determine the optimal sites for the insertion of orthodontic mini implants. Cone-beam computed tomography (CBCT) images of 32 patients were included in this study. The sample was further categorized into three facial types: low-, average-, and high-angle. OBT and CBT were measured at the mandibular symphysis region. All measurements were performed at six different heights from the cementoenamel junction [CEJ] and at seven different angles to the occlusal plane. Analysis of variance (ANOVA) was used for statistical comparison and a p value less than 0.05 was considered statistically significant. Our results revealed that neither OBT nor CBT was influenced by age or sex, except for the observation that CBT was significantly greater in adults than in adolescents. OBT and CBT were significantly greater in low-angle cases than in average- and high-angle cases. Both OBT and CBT were significantly influenced by insertion locations, heights and angles, and their interactions. CBT and OBT were greatest at the location between two lower central incisors, and became greater with increases in insertion height and angle. Both recommended and optimal insertion sites were mapped. The mandibular symphysis region was suitable for the placement of orthodontic mini implants. The optimal insertion site was 6–10 mm apical to the CEJ between two lower central incisors, with an insertion angle being 0–60 degrees to the occlusal plane.

Orthodontic management of skeletal Class II malocclusion using three mini-implants- A case report

Vertical dimension issues are frequently regarded as the most difficult dentofacial problems to treat in clinical practice. The difficulty level increases when vertical dysplasia is paired with sagittal discrepancy. The use of mini-implants in Orthodontics has broadened the scope of orthodontic treatment options. The treatment of a 14-year-old female patient with skeletal Class II malocclusion, slight hyperdivergent profile, and enhanced incisor visibility with four premolar extraction followed by comprehensive orthodontic treatment to correct the convex profile and increased incisor visibility, with two posterior implants for retraction and a midline mini implant for intrusion of the anterior maxillary dentoalveolar segment is described in this case report. The active therapy period was 25 months long.

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.

Deflection of mini implants from its intended path of placement on varying bone densities.

Knowledge of bone density in maxilla and mandible will allow the clinician to plan the anchorage strategies and placement of implants with necessary precautions. The study aims to evaluate the deflection changes of titanium alloy self-drilling mini implants from the intended path that occurs during placement in varying bone densities. 63 titanium alloy self-drilling mini implants of the lengths 6mm, 8mm, and 10mm with diameter of 1.3mm were placed in three homogenous solid rigid polyurethane foam (saw bone) with bone densities of 20pcf, 30pcf, and 40pcf simulating anatomic sites in maxilla and mandible. 7mini implants of each length in all bone densities were tested for study. The implants were inserted perpendicularly into artificial bone block held in a custom made stand. The bone blocks were then radiographically exposed and the deviation of the long axis of the implantfrom a true vertical line was measured. There was a decrease in deflection of the mini implant with increase in density. On the other hand, increase in length resulted in increase in the amount of deflection. Longer mini implants can be used in less dense bone as in maxilla, whereas shorter mini implants can be used in high dense bone as in mandible to increase the stability and success rate of implants. Bone density and implant length play a role in deflection of mini implant from its intended path of insertion. Key words:Orthodontic Mini implants, deflection, bone density, anchorage.

USE OF TEMPORARY ANCHORAGE DEVICES IN INTRUSION OF SUPRAERUPTED MOLARS-CASE REPORTS

Early loss of mandibular permanent molars with supraeruption of maxillary permanent molars is a common clinical finding causing functional posterior occlusion problems. Rehabilitation of the stomatognathic system often requires preprosthodontic intervention with molar intrusion which is one of the most difficult movements in orthodontic mechanics requiring efficient anchorage to achieve success. The aim of this article was to present two case reports, with orthodontic mini-implants used for molar intrusion as preprosthetic treatment, reducing the need for prosthetic crown reduction in patients with edentulous space discrepancy. With the aid of chain elastics, the force of intrusion passing through the center of resistance of the tooth, supraerupted maxillary molars were intruded approximately 0.5mm per month. The intrusive tooth movement maintained the vitality of the intruded teeth and was not aggressive to the periodontal structures, did not cause root resorption and no change of the pulp flow was detected. In contrast to traditional orthodontics, mini-implants were demonstrated to be clinically efficient in providing sufficient anchorage against orthodontic forces. With these devices using well-controlled magnitude and direction of the force, we reestablished successfully the functional posterior occlusion. Through this case reports, we emphasize the versatility of orthodontic mini-implants as a form of temporary anchorage devices (TADs) in the biomechanics of molar intrusion attempted to create interocclusal space for adequate prosthodontic restoration with osseointegrated implants and prosthesis. Keywords: Temporary anchorage devices (TADs), Mini-implants, Molar intrusion, Edentulous space discrepancy, Preprosthodontic therapy.

Chlorhexidine for the Treatment of Peri-Implantitis: Is it a Benison?

Chlorhexidine is the most favored and widely used antimicrobial agent for the treatment of peri-implantitis. But, not many clinicians are aware of its side effects on dental implants and its cytotoxic effects on osteoblasts. The objectives of this review are to study the effect of chlorhexidine on osteoblasts as well as on the surface topography of dental implants. MEDLINE-PubMed (The National Library of Medicine, Washington DC) was used as a search engine. Databases were searched from 2010 to 2020 were explored using the following terms: "dental implant surface," "chlorhexidine mouthwash," "osteoblast cells," "osseointegration." From the total hits obtained, each article along with its cross-reference was manually read and filtered based on the focused question. The inclusion criteria included articles published only in English language involving human studies, randomized control trials, in vitro studies, and review articles. Exclusion criteria included studies published in languages other than English, orthodontic mini-implants, and pilot studies. The final process involved scrutinizing for any duplicate content of the hand searched articles. Following this, data was extracted from the compiled hand searched articles to obtain relevant information for the review. Chlorhexidine alters the surface topography of dental implants and causes cell cytotoxicity. This, in turn, can hinder the re-osseointegration potential and hence cause dental implant failure. It is, therefore, recommended to discourage the use of chlorhexidine as a surface decontaminant for peri-implantitis cases and practice implementing other antimicrobial agents.

Correlation between cortical bone thickness at mini-implant insertion sites and age of patient.

ABSTRACTIntroduction: Orthodontic mini-implants (MI) are a reliable alternative to provide temporary orthodontic anchorage. Prior to miniscrew insertion, the best approach would be to evaluate each possible insertion site and measure the cortical bone thickness, and verify whether it would provide adequate primary stability. Objective: This study aimed to evaluate the difference in cortical bone thickness in areas of mini-implants insertion in patients of different ages, by means of cone beam computed tomography (CBCT). Methods: The sample of this retrospective study was composed of 123 CBCT scans, which were used to measure cortical bone thickness in the buccal and palatal inter-radicular space in the mesial region of the first permanent molars. These measures were compared by using the Student’s t-test, ANOVA/Tukey tests, and Linear regression between male and female subjects, from 12 to 30 years old. Results: No significant difference was found in cortical bone thickness between sex, race and sagittal facial patterns. Significantly higher measurement values were observed in patients older than 12 years of age at all sites evaluated. The coefficient β at the adjusted linear regression analysis showed that at each increment in age, mean cortical thickness values increased by 0.06mm in the mandible, 0.03mm in the buccal region and 0.02mm in the palatal region of the maxilla. Conclusions: The increase in cortical bone thickness was positively associated with age; that is, the more advanced the patient’s age was, the less chance there was of failure due to primary stability.

Recent Advancements in Orthodontic Anchorage Using Mini-Implants

Orthodontic mini-implants are a relatively newer form of anchorage compared to the conventional intraoral and extraoral anchorage appliances. Mini-implants can be used for the correction of a wide range of orthodontic malocclusions. This article reviews the current evidence on mini-implants regarding the clinical uses, and comparing it with conventional anchorage appliances. This article reports the difference between orthodontic mini-implants and prosthetic dental implants. It also reviews the information on how orthodontic mini-implants can be used for obtaining anchorage in antero-posterior, transverse, and vertical dimension. The biomechanical considerations of orthodontic treatment with conventional anchorage and mini-implants is presented in this paper.

Orthodontic mini-implants: clinical and peri-implant evaluation.

The study evaluated the clinical changes of orthodontic mini-implants (MI) inserted for the purpose of anchoring during orthodontic treatment. The null hypotheses were: 1-that there is no correlation between proximity of the MI to the root and peri-implantitis or mobility; 2-that peri-implantitis does not interfere with mobility; 3-that the pain is not related to mobility or peri-implantitis. Forty (40) patients were selected and the MI were evaluated for each patient. MI in the upper and lower arch were evaluated for a period of approximately 6 months with relationship to the distance MI - root, peri-implantitis, mobility, biological damage and pain through the analysis of periapical radiography and clinical/periodontal evaluation. The evaluations were performed out by means of scores and a correlation was made between the variables. No statistically significant differences were found between the upper and lower arch in the variables evaluated, except for the mobility that was more present in the lower arch (p = 0.0336). There was a correlation between peri-implantitis and mobility (p = 0.0003) and between pain and mobility (p = 0.0443). However, there was no correlation between a greater degree of peri-implantitis and greater mobility (p = 0.7054). In addition, the MI placed too close to the root showed peri-implantitis (p = 0.0142). The null hypotheses were rejected because there was a positive correlation between the analyzes. The placement of MI close to the root led to greater peri-implantitis. Patients who reported pain had greater mobility of the MI and peri-implantitis led to greater mobility.

Effects of self-ligating brackets and other factors influencing orthodontic treatment outcomes: A prospective cohort study.

ObjectiveThe purpose of this study was to evaluate the effects of self-ligating brackets (SBs) and other factors that influence orthodontic treatment outcomes.MethodsThis two-armed cohort study included consecutively treated patients in a private practice. The patients were asked to choose between SBs and conventional brackets (CBs); if any patient did not have a preference, he or she was randomly allocated to the CB or SB group. All patients were treated using an identical archwire sequence. Evaluated parameters were as follows treatment duration, number of bracket failures, poor oral hygiene, poor elastic wear, extraction, use of orthodontic mini-implants (OMI), OMI failure, American Board of Orthodontics (ABO) Discrepancy Index (DI), arch length discrepancy, and ABO Cast-Radiograph Evaluation (CRE) score. Stepwise regression analysis was performed to generate the equation for prediction of the CRE.ResultsThe final sample comprised 134 patients with an average age of 22.73 years. The average DI, CRE, and treatment duration were 21.81, 14.25, and 28.63 months, respectively. Analysis of covariance showed a significant difference in CRE between the CB and SB groups after adjusting for the effects of confounding variables. Stepwise regression analysis using four variables, namely extraction, SB use, poor elastic wear, and additional appliance use, could explain only 25.2% of the variance in the CRE.ConclusionsAlthough the CRE was significantly better for CBs than for SBs, the clinical significance of this result seems to be limited. Extraction, SB use, poor elastic wear, and additional appliance use may have significant effects on treatment outcomes.

How is Dentists Using CBCT in Their Clinics? - A Review Article

Cone beam computed tomography (CBCT) was introduced in 1997. The aim of this article was to evaluate how CBCT are being used in dental clinics and identify different factors such as workflow of CBCT scan procedure and indications of CBCT. The most common indications for CBCT are implant treatment planning, planning for orthodontic mini-implants, evaluation of periodontal structures, airway, and temporomandibular joint. The enhancements in the digital software can be used for evaluation of CBCT such as contrast, brightness, zoom, etc. The interpretation of CBCT is performed by dentists, dental specialists, and oral radiologists. There are some challenges in CBCT such as artifacts and cost. However, the utility of CBCT may offset these disadvantages when indicated. This review articles describes how dentists use the CBCT in their clinical practice.

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.

Correlation between insertion torque and peri-implant bone strain during placement of orthodontic mini-implants: A finite element study

Insertion torque is the amount of torque exerted on the implant to tighten into the bone. We investigated whether insertion torque values could be correlated with the strain level in the peri-implant cortical bone resulting from mini-implant insertion. The insertion of a standard size mini-implant (φ1.4mm×7mm) into maxillary alveolar bone was simulated using the finite element method. A total of 3600 calculation steps were employed to numerically reproduce the mini-implant insertion process and analyze the insertion torque and strain distribution in bone. Special attention was given to the relationship between insertion torque values and strain level in the cortical bone at the final tightening. The strain level was quantified using the following 3 strain parameters: (1) average insertion strain, (2) peak insertion strain recorded near the mini-implant thread tips, and (3) the size of the damage zone in the cortical bone. Correlations between the insertion torque values and these 3 parameters were analyzed using linear regression. Direct proportionality and strong correlation were found between the insertion torque values and each of the 3 strain parameters: average insertion strain (r2=0.91), peak insertion strain (r2=0.91), and the size of damage zone (r2=0.90) in the peri-implant cortical bone. The results of this finite element method study demonstrated that insertion torque could serve as a reliable indicator of the strain level in the peri-implant cortical bone resulting from mini-implant insertion.

Intrusion of Maxillary Incisors Using Orthodontic Mini-Implants in an Adult Patient with Deep Bite and Excessive Gingival Display

Intrusion of Maxillary Incisors Using Orthodontic Mini-Implants in an Adult Patient with Deep Bite and Excessive Gingival Display

Non-surgical management of a young adult with Class II Skeletal Base and vertical maxillary excess using Mini Implants

Class II skeletal dysplasias have always been a challenge in orthodontics and often require surgical management in adjunct to Orthodontics in non growing patients when presented with a severe discrepancy. Difficulty increases more when the patient also has a vertical dysplasia in congruence with a sagittal discrepancy. The advent of mini implants in orthodontics has expanded the envelope of camouflage treatment. This case report presents a female patient with a skeletal Class II base attributable to retrognathic mandible and an orthognathic maxilla showing Vertical Maxillary excess, treated non-extraction with absolute intrusion of maxillary arch using Infra zygomatic crestal (IZC) bone screws bilaterally in the posterior and two inter radicular implants in the anterior region. Keywords: Absolute intrusion, Infra Zygomatic Crestal implants, Mini implants