Seong-Hun Kim - Academia.edu (original) (raw)

Papers by Seong-Hun Kim

Research paper thumbnail of Do sand blasted with large grit and acid etched surface treated mini-implants remain stationary under orthodontic forces?

The Angle Orthodontist, 2012

Objectives: To determine the positional stability of sand blasted, large grit, and acid-etched (S... more Objectives: To determine the positional stability of sand blasted, large grit, and acid-etched (SLA) surface-treated mini-implants (C-implants) used as the exclusive source of anchorage during en masse retraction. Materials and Methods: A retrospective clinical investigation was performed comparing pretreatment cone beam computed tomography (CBCT) images with those taken after en masse retraction of the six anterior teeth. Force was applied to 16 C-implants (1.8 mm in diameter, 8.5 mm in length) placed between the upper second premolars and first molars. Three-dimensional superimposition of CBCT data using mutual information was used to evaluate the positional difference of C-implants between preretraction and postretraction CBCT data. Results: There was no significant difference in mini-implant position between the preretraction and postretraction CBCT evaluation. Conclusions: The SLA-coated C-implant provides stationary anchorage as well as stable anchorage during orthodontic tooth movement. (Angle Orthod. 2012;82:304-312.

Research paper thumbnail of Film Image Transfer System (FITS): An Efficient Method for Proper Positioning of Orthodontic Mini-implants

Journal of Korean Dental Science, 2011

Purpose: To describe the newly developed Film image transfer system (FITS) for proper positioning... more 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 miniimplant 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.

Research paper thumbnail of Effects of a new type of clear overlay retainer on occlusal contacts

The Korean Journal of Orthodontics, 2017

The popularity of clear overlay retainers (CORs) has increased recently because of their advantag... more The popularity of clear overlay retainers (CORs) has increased recently because of their advantages such as better esthetics, cost effectiveness, easy fabrication, and good compliance. However, a deficiency in posterior occlusal settling is a reported limitation of CORs. The aim of this study was to evaluate the posterior occlusal contact changes in a new type of clear orthodontic retainer called Oral-treaper (OTP), which consists of three layers and has stronger mechanical characteristics than do conventional retainers. Three patients who completed fixed orthodontic treatment received OTP as a removable retainer. Cast models were fabricated after the removal of fixed appliances (T1) and after 4 to 11 months of using the retainers (T2). We evaluated all the cast models to compare the post-orthodontic settling pattern during the use of the OTPs. The depth of occlusal contacts was evaluated using color maps. The OTP did not prevent vertical settling in all patients but resulted in an improvement in posterior occlusal contact points.

Research paper thumbnail of Displacement pattern of the anterior segment using antero-posterior lingual retractor combined with a palatal plate

Korean journal of orthodontics, 2015

To evaluate and compare the effects of two appliances on the en masse retraction of the anterior ... more To evaluate and compare the effects of two appliances on the en masse retraction of the anterior teeth anchored by temporary skeletal anchorage devices (TSADs). The sample comprised 46 nongrowing hyperdivergent adult patients who planned to undergo upper first premolar extraction using lingual retractors. They were divided into three groups, based on the lingual appliance used: the C-lingual retractor (CLR) group (group 1, n = 16) and two antero-posterior lingual retractor (APLR) groups (n = 30, groups 2 and 3). The APLR group was divided by the posterior tube angulation; posterior tube parallel to the occlusal plane (group 2, n = 15) and distally tipped tube (group 3, n = 15). A retrospective clinical investigation of the skeletal, dental, and soft tissue relationships was performed using lateral cephalometric radiographs obtained pretreatment and post en masse retraction of the anterior teeth. All groups achieved significant incisor and canine retraction. The upper posterior teeth...

Research paper thumbnail of A new type of clear orthodontic retainer incorporating multi-layer hybrid materials

Korean journal of orthodontics, 2015

Clear thermoplastic retainers have been widely used in daily orthodontics; however, they have inh... more Clear thermoplastic retainers have been widely used in daily orthodontics; however, they have inherent limitations associated with thermoplastic polymer materials such as dimensional instability, low strength, and poor wear resistance. To solve these problems, we developed a new type of clear orthodontic retainer that incorporates multi-layer hybrid materials. It consists of three layers; an outer polyethylenterephthalate glycol modified (PETG) hard-type polymer, a middle thermoplastic polyurethane (TPU) soft-type polymer, and an inner reinforced resin core. The resin core improves wear resistance and mechanical strength, which prevent unwanted distortion of the bucco-palatal wall of the retainer. The TPU layer absorbs impact and the PETG layer has good formability, optical qualities, fatigue resistance, and dimensional stability, which contributes to increased support from the mandibular dentition, and helps maintain the archform. This new type of vacuum-formed retainer showed impr...

Research paper thumbnail of New approach of maxillary protraction using modified C-palatal plates in Class III patients

Korean journal of orthodontics, 2015

Maxillary protraction is the conventional treatment for growing Class III patients with maxillary... more Maxillary protraction is the conventional treatment for growing Class III patients with maxillary deficiency, but it has undesirable dental effects. The purpose of this report is to introduce an alternative modality of maxillary protraction in patients with dentoskeletal Class III malocclusion using a modified C-palatal plate connected with elastics to a face mask. This method improved skeletal measurements, corrected overjet, and slightly improved the profile. The patients may require definitive treatment in adolescence or adulthood. The modified C-palatal plate enables nonsurgical maxillary advancement with maximal skeletal effects and minimal dental side effects.

Research paper thumbnail of Periodontal responses to augmented corticotomy with collagen membrane application during orthodontic buccal tipping in dogs

BioMed research international, 2014

This prospective randomized split-mouth study was performed to examine the effects of absorbable ... more This prospective randomized split-mouth study was performed to examine the effects of absorbable collagen membrane (ACM) application in augmented corticotomy using deproteinized bovine bone mineral (DBBM), during orthodontic buccal tipping movement in the dog. After buccal circumscribing corticotomy and DBBM grafting into the decorticated area, flaps were repositioned and sutured on control sides. ACM was overlaid and secured with membrane tacks, on test sides only, and the flaps were repositioned and sutured. Closed coil springs were used to apply 200 g orthodontic force in the buccolingual direction on the second and third premolars, immediately after primary flap closure. The buccal tipping angles were 31.19 ± 14.60° and 28.12 ± 11.48° on the control and test sides, respectively. A mean of 79.5 ± 16.0% of the buccal bone wall was replaced by new bone on the control side, and on the test side 78.9 ± 19.5% was replaced. ACM application promoted an even bone surface. In conclusion, ...

Research paper thumbnail of Tooth movement out of the bony wall using augmented corticotomy with nonautogenous graft materials for bone regeneration

BioMed research international, 2014

This prospective randomized split-mouth study was performed to compare the effects of augmented c... more This prospective randomized split-mouth study was performed to compare the effects of augmented corticotomy with those of different nonautogenous bone graft materials combined with orthodontic tooth movement in dogs. Decortication was performed on the buccal bone surface of 6 male beagle dogs that were randomly assigned to receive grafts of deproteinized bovine bone mineral, irradiated cortical bone, or synthetic bone. Immediate orthodontic force was applied to the second and third premolars for buccal tipping for 6 weeks. The pocket depth and width of keratinized tissue (WKT) were measured. Histologic and histomorphometric analyses were performed. The probing depth, WKT, and ratio of the area of new bone to that of total bone on the buccal side were not significantly different between groups. All groups had considerable new bone formation on the pressure side. New bone formation on the buccal side and buccal plate formation in the coronal direction along the root surfaces were indu...

Research paper thumbnail of Treatment and retention of relapsed anterior open-bite with low tongue posture and tongue-tie: A 10-year follow-up

Korean journal of orthodontics, 2014

The purpose of the current report is to present 6-year long-term stability and 10-year follow-up ... more The purpose of the current report is to present 6-year long-term stability and 10-year follow-up data for an adult patient who was treated with a tongue elevator for relapsed anterior open-bite. The 19-year-old male patient presented with the chief complaint of difficulty in chewing his food. Collectively, clinical and radiographic examinations revealed an anterior open-bite, low tongue posture, and tongue-tie. The patient opted for orthodontic treatment alone, without any surgical procedure. A lingual frenectomy was recommended to avoid the risk of relapse, but the patient declined because he was not experiencing tongue discomfort. Initial treatment of the anterior open-bite with molar intrusion and tongue exercises was successful, but relapse occurred during the retention period. A tongue elevator was used for retreatment, because the approach was minimally invasive and suited the patient's requirements regarding discomfort, cost, and time. The appliance changed the tongue pos...

Research paper thumbnail of Severe bimaxillary protrusion with adult periodontitis treated by corticotomy and compression osteogenesis

The Korean Journal of Orthodontics, 2009

Research paper thumbnail of Finite-element analysis of the shift in center of resistance of the maxillary dentition in relation to alveolar bone loss

The Korean Journal of Orthodontics, 2009

The aim of this study was to investigate the changes in the center of resistance of the maxillary... more The aim of this study was to investigate the changes in the center of resistance of the maxillary teeth in relation to alveolar bone loss. Methods: A finite element model, which included the upper dentition and periodontal ligament, was designed according to the amount of bone loss (0 mm, 2 mm, 4 mm). The teeth in each group were fixed with buccal and lingual arch wires and splint wires. Retraction and intrusion forces of 200 g for 4 and 6 anterior teeth groups and 400 g for the full dentition group were applied. Results: The centers of resistance were at 13.5 mm, 14.5 mm, 15 mm apical and 12 mm, 12 mm, 12.5 mm posterior in the 4 incisor group; 13.5 mm, 14.5 mm, 15 mm apical and 14 mm, 14 mm, 14.5 mm posterior in the 6 anterior teeth group; and 11 mm, 13 mm, 14.5 mm apical and 26.5 mm, 27 mm, 25.5 mm posterior in the full dentition group respectively according to 0 mm, 2 mm, 4 mm bone loss. Conclusions: The center of resistance shifted apically and posteriorly as alveolar bone loss increased in 4 and 6 anterior teeth groups. However, in the full dentition group, the center of resistance shifted apically and anteriorly in the 4 mm bone loss model.

Research paper thumbnail of Torque control during lingual anterior retraction without posterior appliances

The Korean Journal of Orthodontics, 2013

Objective: To evaluate the factors that affect torque control during anterior retraction when uti... more Objective: To evaluate the factors that affect torque control during anterior retraction when utilizing the C-retractor with a palatal miniplate as an exclusive source of anchorage without posterior appliances. Methods: The C-retractor was modeled using a 3-dimensional beam element (0.9-mm-diameter stainless-steel wire) attached to mesh bonding pads. Various vertical heights and 2 attachment positions for the lingual anterior retraction hooks (LARHs) were evaluated. A force of 200 g was applied from each side hook of the miniplate to the splinted segment of 6 or 8 anterior teeth. Results: During anterior retraction, an increase in the LARH vertical height increased the amount of lingual root torque and intrusion of the incisors. In particular, with increasing vertical height, the tooth displacement pattern changed from controlled tipping to bodily displacement and then to lingual root displacement. The effects were enhanced when the LARH was located between the central and lateral incisors, as compared to when the LARH was located between the lateral incisors and canines. Conclusions: Three-dimensional lingual anterior retraction of the 6 or 8 anterior teeth can be accomplished using the palatal miniplate as the only anchorage source. Using LARHs at different heights or positions affects the quality of torque and intrusion.

Research paper thumbnail of Accelerated Tooth Movement and Temporary Skeletal Anchorage Devices (TSADs)

International journal of dentistry, 2014

Research paper thumbnail of En-masse retraction with a preformed nickel-titanium and stainless steel archwire assembly and temporary skeletal anchorage devices without posterior bonding

Korean journal of orthodontics, 2014

To evaluate the therapeutic effects of a preformed assembly of nickel-titanium (NiTi) and stainle... more To evaluate the therapeutic effects of a preformed assembly of nickel-titanium (NiTi) and stainless steel (SS) archwires (preformed C-wire) combined with temporary skeletal anchorage devices (TSADs) as the sole source of anchorage and to compare these effects with those of a SS version of C-wire (conventional C-wire) for en-masse retraction. Thirty-one adult female patients with skeletal Class I or II dentoalveolar protrusion, mild-to-moderate anterior crowding (3.0-6.0 mm), and stable Class I posterior occlusion were divided into conventional (n = 15) and preformed (n = 16) C-wire groups. All subjects underwent first premolar extractions and en-masse retraction with pre-adjusted edgewise anterior brackets, the assigned C-wire, and maxillary C-tubes or C-implants; bonded mesh-tube appliances were used in the mandibular dentition. Differences in pretreatment and post-retraction measurements of skeletal, dental, and soft-tissue cephalometric variables were statistically analyzed. Both...

Research paper thumbnail of Stress distribution and displacement by different bone-borne palatal expanders with micro-implants: a three-dimensional finite-element analysis

The European Journal of Orthodontics, 2012

The aim of this study was to analyze stress distribution and displacement of the maxilla and teet... more The aim of this study was to analyze stress distribution and displacement of the maxilla and teeth according to different designs of bone-borne palatal expanders using micro-implants. A threedimensional (3D) finite-element (FE) model of the craniofacial bones and maxillary teeth was obtained. Four designs of rapid maxillary expanders: one with micro-implants placed lateral to mid-palatal suture (type 1), the second at the palatal slope (type 2), the third as in type 1 with additional conventional Hyrax arms (type 3), and the fourth surgically assisted tooth-borne expander (type 4) were added to the FE models. Expanders were activated transversely for 0.25 mm. Geometric nonlinear theory was applied to evaluate Von-Mises Stress distribution and displacement. All types exhibited downward displacement and demonstrated more horizontal movement in the posterior area. Type 3 showed the most transverse displacement. The rotational movement of dentoalveolar unit was larger in types 1 and 3, whereas it was relatively parallel in types 2 and 4. The stresses were concentrated around the micro-implants in types 1 and 3 only. Type 2 had the least stress concentrations around the anchorage and showed alveolar expansion without buccal inclination. It is recommended to apply temporary anchorage devices to the palatal slopes to support expanders for efficient treatment of maxillary transverse deficiency.

Research paper thumbnail of Resistance to Immediate Orthodontic Loading of Surface-Treated Mini-Implants

The Angle Orthodontist, 2010

Objective: To test the hypothesis that there is no difference in the stability and resistance to ... more Objective: To test the hypothesis that there is no difference in the stability and resistance to orthodontic forces of immediately loaded sandblasted and acid-etched (SAE) mini-implants and those of machined-surface implants of the same size and shape. Materials and Methods: Two types of mini-implants were used in the tibiae of 44 rabbits; some had an SAE surface and some had machined surfaces. Orthodontic loading of 150 g was applied immediately after placement. The success rates and maximum removal torque values (RTVs) of 412 mini-implants were recorded and compared immediately after placement, 3 days after placement, and 1, 6, and 10 weeks after placement. The RTV data were analyzed using multiple regression analysis to evaluate differences with respect to surface treatment, loading, and loading periods (P , .05). Multiple comparisons using the Scheffé method were performed to evaluate the RTVs for the subsequent loading periods. Results: Thirteen mini-implants failed during the experimental period. The SAE group had a higher RTV than the machined group, and there was significant difference in RTVs in accordance with loading periods (P , .001). However, there was no significant RTV difference between loaded and unloaded mini-implants. Conclusions: The hypothesis was supported. Both SAE mini-implants and machined miniimplants can be loaded immediately and experience similar success rates. RTVs were higher for the SAE mini-implants than for the machined mini-implants. The latter finding suggests that, for immediate loading, SAE mini-implants may provide more stable retention than machined miniimplants.

Research paper thumbnail of Unusual Extraction Treatment in Class II division 1 Using C-Orthodontic Mini-Implants

The Angle Orthodontist, 2007

This paper describes the treatment of a female patient, aged 23 years and 5 months, with a Class ... more This paper describes the treatment of a female patient, aged 23 years and 5 months, with a Class II division 1 malocclusion, who showed severe anterior protrusion and lower anterior crowding. Specially-designed orthodontic mini-implants were placed bilaterally in the interdental space between both the upper and the lower posterior teeth. Both lower first molars showed severe apical lesions. Therefore, the treatment plan consisted of extraction of both upper first premolars and lower first molars, en masse retraction of the upper six anterior teeth, lower anterior alignment, and protraction of all the lower molars. C-implants® were used as substitutes for maxillary posterior anchorage teeth during anterior retraction and as hooks for mandibular molar protraction. The correct overbite and overjet were obtained by intruding and retracting the upper six anterior teeth into their proper positions. The dentition was detailed using conventional orthodontic appliances. The upper C-implants ...

Research paper thumbnail of Rotational Resistance of Surface-Treated Mini-Implants

The Angle Orthodontist, 2009

Objective: To test the hypothesis that there is no difference in the stability and resistance to ... more Objective: To test the hypothesis that there is no difference in the stability and resistance to rotational moments of early loaded sandblasted and acid-etched (SLA) mini-implants and those of machined-surface implants of the same size and shape. Materials and Methods: A randomized complete block design was used in 12 skeletally mature male beagle dogs. Ninety-six orthodontic mini-implants were tested. Two types of implants were used: some had SLA surface treatment and some had machined surfaces without coating. After 3 weeks of healing, rotational moments of 150 g were applied. The success rates, maximum torque values, angular momentum, and total energy absorbed by the bone were compared. All values were subjected to mixed-model analysis to evaluate the influence of surface treatment, rotational force direction, and site of implantation. Results: The maximum insertion torque and angular momentum of SLA implants were significantly lower than those of machined implants (P = .034, P =...

Research paper thumbnail of Mandibular dimensions of subjects with asymmetric skeletal Class III malocclusion and normal occlusion compared with cone-beam computed tomography

American Journal of Orthodontics and Dentofacial Orthopedics, 2012

The purpose of this study was to use cone-beam computed tomography to compare mandibular dimensio... more The purpose of this study was to use cone-beam computed tomography to compare mandibular dimensions in subjects with asymmetric skeletal Class III malocclusion and those with normal occlusion. Methods: Cone-beam computed tomography scans of 38 subjects with normal occlusion and 28 patients with facial asymmetry were evaluated and digitized with Invivo software (Anatomage, San Jose, Calif). Three midsagittal and 13 right and left measurements were taken. The paired t test was used to compare the right and left sides in each group. The Mann-Whitney U test was used to compare the midsagittal variables and the differences between the 2 sides of the group with normal occlusion with those of asymmetry patients. Results: The posterior part of the mandibular body showed significant differences between the deviated and nondeviated sides in asymmetric Class III patients. The difference of the asymmetry group was significantly greater than that of the normal occlusion group for the mediolateral ramal and the anteroposterior condylar inclinations (P 5 0.007 and P 5 0.019, respectively). Conclusions: The asymmetric skeletal Class III group showed significant differences in condylar height, ramus height, and posterior part of the mandibular body compared with the subjects with normal occlusion. These results might be useful for diagnosis and treatment planning of asymmetric Class III patients.

Research paper thumbnail of Corticotomy-assisted decompensation for augmentation of the mandibular anterior ridge

American Journal of Orthodontics and Dentofacial Orthopedics, 2011

Introduction: This article introduces a technique combining corticotomy and orthodontic forces, o... more Introduction: This article introduces a technique combining corticotomy and orthodontic forces, or accelerated osteogenic orthodontics, for use in patients with a Class III occlusion and a thin alveolus who will undergo orthognathic surgery. Methods: Two adults with Class III malocclusion undergoing anterior decompensation for mandibular setback surgery were selected. The first patient was treated with accelerated osteogenic orthodontics and conventional decompensation. The second patient was treated with accelerated osteogenic orthodontics and decompensation with a temporary skeletal anchorage device in concert with guided tissue regeneration. Decortication of bone was performed to the mandibular teeth with a low-speed round bur and piezosurgery. After hemostasis, bone graft material was placed into the decorticated area. In the severely thin alveolar ridge, a rigid scaffold was applied for immobilization of graft material. After approximation of the flap, an immediate orthodontic force was applied to the teeth to initiate rapid tooth movement. Results: Rapid tooth movement into predetermined positions for orthognathic surgery was accomplished in all mandibular anterior teeth. Preoperative 3-dimensional imaging showed dehiscences on the facial aspects of the mandibular anterior teeth. Postoperative imaging demonstrated coverage of the denuded roots with radiodense material. Conclusions: The accelerated osteogenic orthodontic technique is a safe and effective treatment option for mandibular anterior decompensation treatment of these patients. When combined with a temporary skeletal anchorage device and bone augmentation, this technique facilitated the decompression of the mandibular anterior teeth in severely compromised dentitions.

Research paper thumbnail of Do sand blasted with large grit and acid etched surface treated mini-implants remain stationary under orthodontic forces?

The Angle Orthodontist, 2012

Objectives: To determine the positional stability of sand blasted, large grit, and acid-etched (S... more Objectives: To determine the positional stability of sand blasted, large grit, and acid-etched (SLA) surface-treated mini-implants (C-implants) used as the exclusive source of anchorage during en masse retraction. Materials and Methods: A retrospective clinical investigation was performed comparing pretreatment cone beam computed tomography (CBCT) images with those taken after en masse retraction of the six anterior teeth. Force was applied to 16 C-implants (1.8 mm in diameter, 8.5 mm in length) placed between the upper second premolars and first molars. Three-dimensional superimposition of CBCT data using mutual information was used to evaluate the positional difference of C-implants between preretraction and postretraction CBCT data. Results: There was no significant difference in mini-implant position between the preretraction and postretraction CBCT evaluation. Conclusions: The SLA-coated C-implant provides stationary anchorage as well as stable anchorage during orthodontic tooth movement. (Angle Orthod. 2012;82:304-312.

Research paper thumbnail of Film Image Transfer System (FITS): An Efficient Method for Proper Positioning of Orthodontic Mini-implants

Journal of Korean Dental Science, 2011

Purpose: To describe the newly developed Film image transfer system (FITS) for proper positioning... more 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 miniimplant 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.

Research paper thumbnail of Effects of a new type of clear overlay retainer on occlusal contacts

The Korean Journal of Orthodontics, 2017

The popularity of clear overlay retainers (CORs) has increased recently because of their advantag... more The popularity of clear overlay retainers (CORs) has increased recently because of their advantages such as better esthetics, cost effectiveness, easy fabrication, and good compliance. However, a deficiency in posterior occlusal settling is a reported limitation of CORs. The aim of this study was to evaluate the posterior occlusal contact changes in a new type of clear orthodontic retainer called Oral-treaper (OTP), which consists of three layers and has stronger mechanical characteristics than do conventional retainers. Three patients who completed fixed orthodontic treatment received OTP as a removable retainer. Cast models were fabricated after the removal of fixed appliances (T1) and after 4 to 11 months of using the retainers (T2). We evaluated all the cast models to compare the post-orthodontic settling pattern during the use of the OTPs. The depth of occlusal contacts was evaluated using color maps. The OTP did not prevent vertical settling in all patients but resulted in an improvement in posterior occlusal contact points.

Research paper thumbnail of Displacement pattern of the anterior segment using antero-posterior lingual retractor combined with a palatal plate

Korean journal of orthodontics, 2015

To evaluate and compare the effects of two appliances on the en masse retraction of the anterior ... more To evaluate and compare the effects of two appliances on the en masse retraction of the anterior teeth anchored by temporary skeletal anchorage devices (TSADs). The sample comprised 46 nongrowing hyperdivergent adult patients who planned to undergo upper first premolar extraction using lingual retractors. They were divided into three groups, based on the lingual appliance used: the C-lingual retractor (CLR) group (group 1, n = 16) and two antero-posterior lingual retractor (APLR) groups (n = 30, groups 2 and 3). The APLR group was divided by the posterior tube angulation; posterior tube parallel to the occlusal plane (group 2, n = 15) and distally tipped tube (group 3, n = 15). A retrospective clinical investigation of the skeletal, dental, and soft tissue relationships was performed using lateral cephalometric radiographs obtained pretreatment and post en masse retraction of the anterior teeth. All groups achieved significant incisor and canine retraction. The upper posterior teeth...

Research paper thumbnail of A new type of clear orthodontic retainer incorporating multi-layer hybrid materials

Korean journal of orthodontics, 2015

Clear thermoplastic retainers have been widely used in daily orthodontics; however, they have inh... more Clear thermoplastic retainers have been widely used in daily orthodontics; however, they have inherent limitations associated with thermoplastic polymer materials such as dimensional instability, low strength, and poor wear resistance. To solve these problems, we developed a new type of clear orthodontic retainer that incorporates multi-layer hybrid materials. It consists of three layers; an outer polyethylenterephthalate glycol modified (PETG) hard-type polymer, a middle thermoplastic polyurethane (TPU) soft-type polymer, and an inner reinforced resin core. The resin core improves wear resistance and mechanical strength, which prevent unwanted distortion of the bucco-palatal wall of the retainer. The TPU layer absorbs impact and the PETG layer has good formability, optical qualities, fatigue resistance, and dimensional stability, which contributes to increased support from the mandibular dentition, and helps maintain the archform. This new type of vacuum-formed retainer showed impr...

Research paper thumbnail of New approach of maxillary protraction using modified C-palatal plates in Class III patients

Korean journal of orthodontics, 2015

Maxillary protraction is the conventional treatment for growing Class III patients with maxillary... more Maxillary protraction is the conventional treatment for growing Class III patients with maxillary deficiency, but it has undesirable dental effects. The purpose of this report is to introduce an alternative modality of maxillary protraction in patients with dentoskeletal Class III malocclusion using a modified C-palatal plate connected with elastics to a face mask. This method improved skeletal measurements, corrected overjet, and slightly improved the profile. The patients may require definitive treatment in adolescence or adulthood. The modified C-palatal plate enables nonsurgical maxillary advancement with maximal skeletal effects and minimal dental side effects.

Research paper thumbnail of Periodontal responses to augmented corticotomy with collagen membrane application during orthodontic buccal tipping in dogs

BioMed research international, 2014

This prospective randomized split-mouth study was performed to examine the effects of absorbable ... more This prospective randomized split-mouth study was performed to examine the effects of absorbable collagen membrane (ACM) application in augmented corticotomy using deproteinized bovine bone mineral (DBBM), during orthodontic buccal tipping movement in the dog. After buccal circumscribing corticotomy and DBBM grafting into the decorticated area, flaps were repositioned and sutured on control sides. ACM was overlaid and secured with membrane tacks, on test sides only, and the flaps were repositioned and sutured. Closed coil springs were used to apply 200 g orthodontic force in the buccolingual direction on the second and third premolars, immediately after primary flap closure. The buccal tipping angles were 31.19 ± 14.60° and 28.12 ± 11.48° on the control and test sides, respectively. A mean of 79.5 ± 16.0% of the buccal bone wall was replaced by new bone on the control side, and on the test side 78.9 ± 19.5% was replaced. ACM application promoted an even bone surface. In conclusion, ...

Research paper thumbnail of Tooth movement out of the bony wall using augmented corticotomy with nonautogenous graft materials for bone regeneration

BioMed research international, 2014

This prospective randomized split-mouth study was performed to compare the effects of augmented c... more This prospective randomized split-mouth study was performed to compare the effects of augmented corticotomy with those of different nonautogenous bone graft materials combined with orthodontic tooth movement in dogs. Decortication was performed on the buccal bone surface of 6 male beagle dogs that were randomly assigned to receive grafts of deproteinized bovine bone mineral, irradiated cortical bone, or synthetic bone. Immediate orthodontic force was applied to the second and third premolars for buccal tipping for 6 weeks. The pocket depth and width of keratinized tissue (WKT) were measured. Histologic and histomorphometric analyses were performed. The probing depth, WKT, and ratio of the area of new bone to that of total bone on the buccal side were not significantly different between groups. All groups had considerable new bone formation on the pressure side. New bone formation on the buccal side and buccal plate formation in the coronal direction along the root surfaces were indu...

Research paper thumbnail of Treatment and retention of relapsed anterior open-bite with low tongue posture and tongue-tie: A 10-year follow-up

Korean journal of orthodontics, 2014

The purpose of the current report is to present 6-year long-term stability and 10-year follow-up ... more The purpose of the current report is to present 6-year long-term stability and 10-year follow-up data for an adult patient who was treated with a tongue elevator for relapsed anterior open-bite. The 19-year-old male patient presented with the chief complaint of difficulty in chewing his food. Collectively, clinical and radiographic examinations revealed an anterior open-bite, low tongue posture, and tongue-tie. The patient opted for orthodontic treatment alone, without any surgical procedure. A lingual frenectomy was recommended to avoid the risk of relapse, but the patient declined because he was not experiencing tongue discomfort. Initial treatment of the anterior open-bite with molar intrusion and tongue exercises was successful, but relapse occurred during the retention period. A tongue elevator was used for retreatment, because the approach was minimally invasive and suited the patient's requirements regarding discomfort, cost, and time. The appliance changed the tongue pos...

Research paper thumbnail of Severe bimaxillary protrusion with adult periodontitis treated by corticotomy and compression osteogenesis

The Korean Journal of Orthodontics, 2009

Research paper thumbnail of Finite-element analysis of the shift in center of resistance of the maxillary dentition in relation to alveolar bone loss

The Korean Journal of Orthodontics, 2009

The aim of this study was to investigate the changes in the center of resistance of the maxillary... more The aim of this study was to investigate the changes in the center of resistance of the maxillary teeth in relation to alveolar bone loss. Methods: A finite element model, which included the upper dentition and periodontal ligament, was designed according to the amount of bone loss (0 mm, 2 mm, 4 mm). The teeth in each group were fixed with buccal and lingual arch wires and splint wires. Retraction and intrusion forces of 200 g for 4 and 6 anterior teeth groups and 400 g for the full dentition group were applied. Results: The centers of resistance were at 13.5 mm, 14.5 mm, 15 mm apical and 12 mm, 12 mm, 12.5 mm posterior in the 4 incisor group; 13.5 mm, 14.5 mm, 15 mm apical and 14 mm, 14 mm, 14.5 mm posterior in the 6 anterior teeth group; and 11 mm, 13 mm, 14.5 mm apical and 26.5 mm, 27 mm, 25.5 mm posterior in the full dentition group respectively according to 0 mm, 2 mm, 4 mm bone loss. Conclusions: The center of resistance shifted apically and posteriorly as alveolar bone loss increased in 4 and 6 anterior teeth groups. However, in the full dentition group, the center of resistance shifted apically and anteriorly in the 4 mm bone loss model.

Research paper thumbnail of Torque control during lingual anterior retraction without posterior appliances

The Korean Journal of Orthodontics, 2013

Objective: To evaluate the factors that affect torque control during anterior retraction when uti... more Objective: To evaluate the factors that affect torque control during anterior retraction when utilizing the C-retractor with a palatal miniplate as an exclusive source of anchorage without posterior appliances. Methods: The C-retractor was modeled using a 3-dimensional beam element (0.9-mm-diameter stainless-steel wire) attached to mesh bonding pads. Various vertical heights and 2 attachment positions for the lingual anterior retraction hooks (LARHs) were evaluated. A force of 200 g was applied from each side hook of the miniplate to the splinted segment of 6 or 8 anterior teeth. Results: During anterior retraction, an increase in the LARH vertical height increased the amount of lingual root torque and intrusion of the incisors. In particular, with increasing vertical height, the tooth displacement pattern changed from controlled tipping to bodily displacement and then to lingual root displacement. The effects were enhanced when the LARH was located between the central and lateral incisors, as compared to when the LARH was located between the lateral incisors and canines. Conclusions: Three-dimensional lingual anterior retraction of the 6 or 8 anterior teeth can be accomplished using the palatal miniplate as the only anchorage source. Using LARHs at different heights or positions affects the quality of torque and intrusion.

Research paper thumbnail of Accelerated Tooth Movement and Temporary Skeletal Anchorage Devices (TSADs)

International journal of dentistry, 2014

Research paper thumbnail of En-masse retraction with a preformed nickel-titanium and stainless steel archwire assembly and temporary skeletal anchorage devices without posterior bonding

Korean journal of orthodontics, 2014

To evaluate the therapeutic effects of a preformed assembly of nickel-titanium (NiTi) and stainle... more To evaluate the therapeutic effects of a preformed assembly of nickel-titanium (NiTi) and stainless steel (SS) archwires (preformed C-wire) combined with temporary skeletal anchorage devices (TSADs) as the sole source of anchorage and to compare these effects with those of a SS version of C-wire (conventional C-wire) for en-masse retraction. Thirty-one adult female patients with skeletal Class I or II dentoalveolar protrusion, mild-to-moderate anterior crowding (3.0-6.0 mm), and stable Class I posterior occlusion were divided into conventional (n = 15) and preformed (n = 16) C-wire groups. All subjects underwent first premolar extractions and en-masse retraction with pre-adjusted edgewise anterior brackets, the assigned C-wire, and maxillary C-tubes or C-implants; bonded mesh-tube appliances were used in the mandibular dentition. Differences in pretreatment and post-retraction measurements of skeletal, dental, and soft-tissue cephalometric variables were statistically analyzed. Both...

Research paper thumbnail of Stress distribution and displacement by different bone-borne palatal expanders with micro-implants: a three-dimensional finite-element analysis

The European Journal of Orthodontics, 2012

The aim of this study was to analyze stress distribution and displacement of the maxilla and teet... more The aim of this study was to analyze stress distribution and displacement of the maxilla and teeth according to different designs of bone-borne palatal expanders using micro-implants. A threedimensional (3D) finite-element (FE) model of the craniofacial bones and maxillary teeth was obtained. Four designs of rapid maxillary expanders: one with micro-implants placed lateral to mid-palatal suture (type 1), the second at the palatal slope (type 2), the third as in type 1 with additional conventional Hyrax arms (type 3), and the fourth surgically assisted tooth-borne expander (type 4) were added to the FE models. Expanders were activated transversely for 0.25 mm. Geometric nonlinear theory was applied to evaluate Von-Mises Stress distribution and displacement. All types exhibited downward displacement and demonstrated more horizontal movement in the posterior area. Type 3 showed the most transverse displacement. The rotational movement of dentoalveolar unit was larger in types 1 and 3, whereas it was relatively parallel in types 2 and 4. The stresses were concentrated around the micro-implants in types 1 and 3 only. Type 2 had the least stress concentrations around the anchorage and showed alveolar expansion without buccal inclination. It is recommended to apply temporary anchorage devices to the palatal slopes to support expanders for efficient treatment of maxillary transverse deficiency.

Research paper thumbnail of Resistance to Immediate Orthodontic Loading of Surface-Treated Mini-Implants

The Angle Orthodontist, 2010

Objective: To test the hypothesis that there is no difference in the stability and resistance to ... more Objective: To test the hypothesis that there is no difference in the stability and resistance to orthodontic forces of immediately loaded sandblasted and acid-etched (SAE) mini-implants and those of machined-surface implants of the same size and shape. Materials and Methods: Two types of mini-implants were used in the tibiae of 44 rabbits; some had an SAE surface and some had machined surfaces. Orthodontic loading of 150 g was applied immediately after placement. The success rates and maximum removal torque values (RTVs) of 412 mini-implants were recorded and compared immediately after placement, 3 days after placement, and 1, 6, and 10 weeks after placement. The RTV data were analyzed using multiple regression analysis to evaluate differences with respect to surface treatment, loading, and loading periods (P , .05). Multiple comparisons using the Scheffé method were performed to evaluate the RTVs for the subsequent loading periods. Results: Thirteen mini-implants failed during the experimental period. The SAE group had a higher RTV than the machined group, and there was significant difference in RTVs in accordance with loading periods (P , .001). However, there was no significant RTV difference between loaded and unloaded mini-implants. Conclusions: The hypothesis was supported. Both SAE mini-implants and machined miniimplants can be loaded immediately and experience similar success rates. RTVs were higher for the SAE mini-implants than for the machined mini-implants. The latter finding suggests that, for immediate loading, SAE mini-implants may provide more stable retention than machined miniimplants.

Research paper thumbnail of Unusual Extraction Treatment in Class II division 1 Using C-Orthodontic Mini-Implants

The Angle Orthodontist, 2007

This paper describes the treatment of a female patient, aged 23 years and 5 months, with a Class ... more This paper describes the treatment of a female patient, aged 23 years and 5 months, with a Class II division 1 malocclusion, who showed severe anterior protrusion and lower anterior crowding. Specially-designed orthodontic mini-implants were placed bilaterally in the interdental space between both the upper and the lower posterior teeth. Both lower first molars showed severe apical lesions. Therefore, the treatment plan consisted of extraction of both upper first premolars and lower first molars, en masse retraction of the upper six anterior teeth, lower anterior alignment, and protraction of all the lower molars. C-implants® were used as substitutes for maxillary posterior anchorage teeth during anterior retraction and as hooks for mandibular molar protraction. The correct overbite and overjet were obtained by intruding and retracting the upper six anterior teeth into their proper positions. The dentition was detailed using conventional orthodontic appliances. The upper C-implants ...

Research paper thumbnail of Rotational Resistance of Surface-Treated Mini-Implants

The Angle Orthodontist, 2009

Objective: To test the hypothesis that there is no difference in the stability and resistance to ... more Objective: To test the hypothesis that there is no difference in the stability and resistance to rotational moments of early loaded sandblasted and acid-etched (SLA) mini-implants and those of machined-surface implants of the same size and shape. Materials and Methods: A randomized complete block design was used in 12 skeletally mature male beagle dogs. Ninety-six orthodontic mini-implants were tested. Two types of implants were used: some had SLA surface treatment and some had machined surfaces without coating. After 3 weeks of healing, rotational moments of 150 g were applied. The success rates, maximum torque values, angular momentum, and total energy absorbed by the bone were compared. All values were subjected to mixed-model analysis to evaluate the influence of surface treatment, rotational force direction, and site of implantation. Results: The maximum insertion torque and angular momentum of SLA implants were significantly lower than those of machined implants (P = .034, P =...

Research paper thumbnail of Mandibular dimensions of subjects with asymmetric skeletal Class III malocclusion and normal occlusion compared with cone-beam computed tomography

American Journal of Orthodontics and Dentofacial Orthopedics, 2012

The purpose of this study was to use cone-beam computed tomography to compare mandibular dimensio... more The purpose of this study was to use cone-beam computed tomography to compare mandibular dimensions in subjects with asymmetric skeletal Class III malocclusion and those with normal occlusion. Methods: Cone-beam computed tomography scans of 38 subjects with normal occlusion and 28 patients with facial asymmetry were evaluated and digitized with Invivo software (Anatomage, San Jose, Calif). Three midsagittal and 13 right and left measurements were taken. The paired t test was used to compare the right and left sides in each group. The Mann-Whitney U test was used to compare the midsagittal variables and the differences between the 2 sides of the group with normal occlusion with those of asymmetry patients. Results: The posterior part of the mandibular body showed significant differences between the deviated and nondeviated sides in asymmetric Class III patients. The difference of the asymmetry group was significantly greater than that of the normal occlusion group for the mediolateral ramal and the anteroposterior condylar inclinations (P 5 0.007 and P 5 0.019, respectively). Conclusions: The asymmetric skeletal Class III group showed significant differences in condylar height, ramus height, and posterior part of the mandibular body compared with the subjects with normal occlusion. These results might be useful for diagnosis and treatment planning of asymmetric Class III patients.

Research paper thumbnail of Corticotomy-assisted decompensation for augmentation of the mandibular anterior ridge

American Journal of Orthodontics and Dentofacial Orthopedics, 2011

Introduction: This article introduces a technique combining corticotomy and orthodontic forces, o... more Introduction: This article introduces a technique combining corticotomy and orthodontic forces, or accelerated osteogenic orthodontics, for use in patients with a Class III occlusion and a thin alveolus who will undergo orthognathic surgery. Methods: Two adults with Class III malocclusion undergoing anterior decompensation for mandibular setback surgery were selected. The first patient was treated with accelerated osteogenic orthodontics and conventional decompensation. The second patient was treated with accelerated osteogenic orthodontics and decompensation with a temporary skeletal anchorage device in concert with guided tissue regeneration. Decortication of bone was performed to the mandibular teeth with a low-speed round bur and piezosurgery. After hemostasis, bone graft material was placed into the decorticated area. In the severely thin alveolar ridge, a rigid scaffold was applied for immobilization of graft material. After approximation of the flap, an immediate orthodontic force was applied to the teeth to initiate rapid tooth movement. Results: Rapid tooth movement into predetermined positions for orthognathic surgery was accomplished in all mandibular anterior teeth. Preoperative 3-dimensional imaging showed dehiscences on the facial aspects of the mandibular anterior teeth. Postoperative imaging demonstrated coverage of the denuded roots with radiodense material. Conclusions: The accelerated osteogenic orthodontic technique is a safe and effective treatment option for mandibular anterior decompensation treatment of these patients. When combined with a temporary skeletal anchorage device and bone augmentation, this technique facilitated the decompression of the mandibular anterior teeth in severely compromised dentitions.