• The korean journal of orthodontics
• /
• v.44 no.4
• /
• pp.177-183
• /
• 2014

Objective: To determine the unique contribution of geometrical design characteristics of orthodontic mini-implants on maximum insertion torque while controlling for the influence of cortical bone thickness. Methods: Total number of 100 cylindrical orthodontic mini-implants was used. Geometrical design characteristics of ten specimens of ten types of cylindrical self-drilling orthodontic mini-implants (Ortho Easy$^{(R)}$, Aarhus, and Dual Top$^{TM}$) with diameters ranging from 1.4 to 2.0 mm and lengths of 6 and 8 mm were measured. Maximum insertion torque was recorded during manual insertion of mini-implants into bone samples. Cortical bone thickness was measured. Retrieved data were analyzed in a multiple regression model. Results: Significant predictors for higher maximum insertion torque included larger outer diameter of implant, higher lead angle of thread, and thicker cortical bone, and their unique contribution to maximum insertion torque was 12.3%, 10.7%, and 24.7%, respectively. Conclusions: The maximum insertion torque values are best controlled by choosing an implant diameter and lead angle according to the assessed thickness of cortical bone.

• Journal of Korean Dental Science
• /
• v.4 no.1
• /
• pp.20-25
• /
• 2011

Purpose: To describe the newly developed Film image transfer system (FITS) for proper positioning of the orthodontic mini-implant in the narrow interdental space and considerations for better application. Materials and Methods: A patient who was planning to have orthodontic mini-implant treatment on the posterior maxilla was recruited to assess the feasibility of FITS. Dental radiographic film and bite record was taken. And then the film image was transferred on the photographic emulsion coated model using transfer light through film projector (enlarger). After exposing the photo emulsion coating on the model, the image was developed with a working solution for a paper developer and fixed. The surgical guide for the mini-implant was fabricated from the transported FITS data. Results: The completed surgical guide was easily placed intraorally, and allowed a simple and rapid placement of the mini-implant. The site of the implant placement was accurate as planned position. Conclusion: In the reported case, The FITS technique represents an effort to minimize risk to the patient and produce consistently good results based upon accurate information about the anatomy of the implant site.

• The Journal of Korean Academy of Prosthodontics
• /
• v.43 no.3
• /
• pp.331-337
• /
• 2005

For a missing teeth, orthodontic treatment may be a better choice of treatment in comparison to a conventional prosthetic replacement such as FPD, resin bonded prosthesis in view of aesthetics, periodontal health and function. Occasionally after an orthodontic treatment, an insufficient space may occur. The mini-implant could be an alternative in situations of narrow ridge dimension, where conventional root form implant could be compromised. The aim of this clinical report is to describe how a space that could not be restored with a traditional root form endosteal implant was managed and to present a technique to achieve optimal anterior esthetics in single implant restoration.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.41 no.5
• /
• pp.240-245
• /
• 2015

Objectives: This study was performed to evaluate patterns of failure time after insertion, failure rate according to loading time after insertion, and the patterns of failure after loading. Materials and Methods: A total of 331 mini-implants were classified into the non-failure group (NFG) and failure group (FG), which was divided into failed group before loading (FGB) and failed group after loading (FGA). Orthodontic force was applied to both the NFG and FGA. Failed mini-implants after insertion, ratio of FGA to NFG according to loading time after insertion, and failed mini-implants according to failed time after loading were analyzed. Results: Percentages of failed mini-implants after insertion were 15.79%, 36.84%, 12.28%, and 10.53% at 4, 8, 12, and 16 weeks, respectively. Mini-implant failure demonstrated a peak from 4 to 5 weeks after insertion. The failure rates according to loading time after insertion were 13.56%, 8.97%, 11.32%, and 5.00% at 4, 8, 12, and 16 weeks, respectively. Percentages of failed mini-implants after loading were 13.79%, 24.14%, 20.69%, and 6.9% at 4, 8, 12, and 16 weeks, respectively. Conclusion: Mini-implant stability is typically acquired 12 to 16 weeks after insertion, and immediate loading can cause failure of the mini-implant. Failure after loading was observed during the first 12 weeks.

• The Journal of the Korean dental association
• /
• v.43 no.3 s.430
• /
• pp.218-224
• /
• 2005

• The korean journal of orthodontics
• /
• v.38 no.5
• /
• pp.328-336
• /
• 2008

Objective: The purpose of this study was to compare the torque resistance to removal of sandblasted large grit and acid etched (SLA) surface treated orthodontic mini-implants and smooth surface orthodontic mini-implants as well as performing histologic observations. Methods: Two groups of custom screw shaped orthodontic mini-implants (C-implant, 1.8 mm outer diameter $\times$ 9.5 mm length, Cimplant, Seoul, Korea) were designated. 22 SLA treated C-implants (SLA group) and 22 machined surface C-implants (machined group) were placed in the tibia metaphysis of 11 adult New Zealand white rabbits. Following a 6-week healing period, the rabbits were sacrificed. Subsequently, the C-implants were removed under reverse torque rotation with a digital torque measuring device and independent t-test was performed. Selected tissues were prepared for histologic observation. Results: The SLA group presented a higher mean removal torque value (6.286 Ncm) than the machined group (4.491 Ncm) which was statistically significant (p < 0.005). Histologic observation revealed a trend of more new bone formation in contact with the screw surface in the SLA group than the smooth group. Conclusions: The results of this study suggested that SLA surface treatment can enhance the osseintegration potential for C-orthodontic mini-implants.

• The korean journal of orthodontics
• /
• v.42 no.4
• /
• pp.159-168
• /
• 2012

Objective: The aims of this study were to investigate mandibular deformation under clenching and to estimate its effect on the stability of orthodontic mini-implants (OMI). Methods: Three finite element models were constructed using computed tomography (CT) images of 3 adults with different mandibular plane angles (A, low; B, average; and C, high). An OMI was placed between #45 and #46 in each model. Mandibular deformation under premolar and molar clenching was simulated. Comparisons were made between peri-orthodontic mini-implant compressive strain (POMI-CSTN) under clenching and orthodontic traction forces (150 g and 200 g). Results: Three models with different mandibular plane angles demonstrated different functional deformation characteristics. The compressive strains around the OMI were distributed mesiodistally rather than occlusogingivally. In model A, the maximum POMI-CSTN under clenching was observed at the mesial aspect of #46 (1,401.75 microstrain [${\mu}E$]), and similar maximum POMI-CSTN was observed under a traction force of 150 g (1,415 ${\mu}E$). Conclusions: The maximum POMI-CSTN developed by clenching failed to exceed the normally allowed compressive cortical bone strains; however, additional orthodontic traction force to the OMI may increase POMI-CSTN to compromise OMI stability.

• The korean journal of orthodontics
• /
• v.41 no.5
• /
• pp.371-378
• /
• 2011

Transposition is defined as a dental anomaly manifested by a positional interchange of 2 adjacent teeth within the same quadrant of the dental arch. Maxillary canine-first premolar [Mx4-3] transposition is the most frequent tooth transposition reported in the literature. In this case report, an orthodontic correction of a transposition of the maxillary left canine and first premolar with the help of palatally located mini-implant anchorage is described. Esthetic and occlusal evaluations suggested alignment of the transposed teeth to their correct anatomic positions in the dental arch. The clinical result at the end of the treatment was satisfactory. Alignment was obtained, and intercuspation was adequate. Nevertheless, the maxillary canine showed facial recession, probably because it was initially positioned buccally. Supporting tissue was examined after treatment and no alveolar bone damage was observed.

• The Journal of the Korean dental association
• /
• v.57 no.11
• /
• pp.654-663
• /
• 2019

This case report describes the management of a 30-year-old woman with hopeless mandibular first molars and right maxillary second premolar. The treatment plan included mandibular second and third molar protraction after extraction of mandibular first molars. Mini-implants were placed between roots of first and second premolar. Sliding mechanics with lever arm was used to prevent inclination of molars. A good functional occlusion was achieved in 38 months without clinically significant side effects. Most of the extraction space of mandibular first molar was closed by protraction of second and third molars. The skeletal Class II pattern was improved by counterclockwise rotation of mandible through reduction of wedge effect. Mandibular molar protraction with orthodontic mini-implants in adequate cases would be a great alternative to prosthetic implant and reduce the financial and surgical burden of patients.

• The korean journal of orthodontics
• /
• v.33 no.3 s.98
• /
• pp.151-156
• /
• 2003

To provide some guideline for microscrew implants, 73 patients that received a total of 180 mini- or microscrew implants were scrutinized. The overall success rate was $93.3\%$ (168 among 180 mini- or microscrew implants) and the mean period of utilization was 15.8 months. Microscrew implants in the UB group (maxillary buccal area) succeeded at a rate of $94.6\%$ (87 among 92), mini- or microscrew implants in the LB group (mandibular buccal area) succeeded $96.6\%$ of the time (56 out of 58), while microscrew implants in the UP group (maxillary palatal area) had a $100\%$ success rate (11 out of 11), and mini- or microscrew implants in the LR group (retromolar area) succeeded in $73.7\%$ of cases (14 among 19). This study might indicate that microscrew implants can be used successfully as orthodontic anchorage in daily orthodontic practice.