Hyo-Sang Park

Kyungpook National University | KNU · Department of Orthodontics

Bacterial infections are a common cause of clinical complications associated with the use of orthodontic microimplants. Biofilm formation on their surfaces and subsequent infection of peri-implant tissues can result in either exfoliation or surgical removal of these medical devices. In order to improve the properties of microimplants, hybrid coatin...

Regarding the influence of facial width on the perception of lip protrusion and its differences between profile and 3-dimensional video clip O ur sincere compliments to Wang et al (Wang ZW, Kim HJ, Noh HK, Park HS. Influence of facial width on the perception of lip protrusion and its differences between profile and 3-dimensional video clip. Am J Or...

Objectives To compare the mandibular posterior space available before treatment and the distance of molar distalization achieved after mandibular dentition distalization with microimplants. Materials and Methods A total of 66 Class I or III adult patients (mean age = 24.46 ± 4.89 years) who underwent molar distalization using microimplants were re...

I appreciate the authors' hard work on the study. I have some questions in this study, and would be grateful to gain additional insights from the authors. Q1. The authors mentioned that the mandible is affected in 74% of facial asymmetric patients, the influence of mandibular asymmetry on the facial soft tissue might be crucial. It seems moderate t...

At the beginning of the research, the author thought the profiles would theoretically be rated similarly because the lip protrusion was identical in each set of 3 profiles. In contrast, the 3-dimensional video clips would influence the raters’ perception of lip protrusion. This is why the author used 2-dimensional (2D) profiles only in the first se...

Introduction: This study aimed to analyze the load-deflection characteristics of an orthodontic cantilever by using the large deflection elastic model. Methods: We experimentally measured the vertical deflections of a cantilever with round or rectangular cross-sections, with lengths of 20 mm and 30 mm, and made of either stainless steel or titanium...

Objectives To compare mandibular incisor compensation relative to Menton (Me) deviation between skeletal Class III patients with roll- and yaw-dominant mandibular asymmetries. Materials and Methods Sixty skeletal Class III patients (21.62 ± 2.69 years) with facial asymmetry were divided into roll- or yaw-dominant asymmetry groups. Mandibular skele...

Introduction: This study evaluated the influence of facial width on the perception of lip protrusion and investigated the concordance between 2-dimensional (2D) profile images and 3-dimensional (3D) video clips in assessing lip protrusion. Methods: An Asian female standard head model was created using 3D modeling software. Eight head models were co...

This case report aimed to describe the effectiveness of myofunctional therapy involving a vertical holding appliance and a smile–clenching–swallow exercise for vertical control, in a growing patient who presented with a high-angle facial pattern. A 10-year-old girl sought treatment for a skeletal open bite. Early interception aimed to reduce the di...

The objective of this study is to compare the shear bond strength (SBS) and the morphological characteristics and chemical compositions of the base surface of newly bonded and rebonded ceramic brackets with different mechanical retention bases. Sixty extracted human premolars were divided into the newly bonded and rebonded groups. Ceramic brackets...

Objectives To investigate the difference in labial and palatal alveolar bone thickness and height during the retention period after incisor retraction treatment with microimplant. Materials and Methods A sample of 21 patients (mean age: 17.80 ± 4.38 years) who underwent incisor retraction treatment using microimplants after premolar extraction was...

Objective This study assessed the differences in soft tissue deviations of the nose, lips, and chin between different mandibular asymmetry types in Class III patients. Methods Cone-beam computed tomography data from 90 Class III patients with moderate-to-severe facial asymmetry were investigated. The sample was divided into three groups based on t...

This case report emphasizes the importance of tongue habit control and careful monitoring in the treatment and stability of anterior open bite. An 8-year-old girl sought treatment for a severe open bite. On clinical examination, the patient was diagnosed with a dental open bite with infantile swallowing. Attempts for habit control using tongue crib...

I appreciate the author's hard work in clarifying the discrepancies in cone-beam computed tomography (CBCT) landmark positioning across various midsag-ittal planes (MSPs) in patients with skeletal Class III facial asymmetry. Since CBCT offers valuable insights that cannot be captured through cephalometrics alone, particularly in diagnosing asymmetr...

Skeletal anchorage is one of the most important innovations in orthodontic treatment in the past 25 years. Orthodontic micro-­implants now enable such difficult movements as retraction of anterior teeth without anchorage loss,1 intrusion of posterior teeth or an entire dentition, and distal movement of an entire arch. Considering the absolute natu...

Objectives: To assess differences in dental compensation of the incisors and first molars in skeletal Class III patients with roll-, yaw-, and translation-dominant mandibular asymmetries. Materials and methods: A total of 90 skeletal Class III adult patients (mean age, 22.00 ± 3.31 years; range, 18-37.9 years) with facial asymmetry were enrolled...

Appropriate orthodontic mechanotherapy, particularly in relation to incisor inclination control is a key consideration for successful treatment and the delivery of optimal aesthetics. A novel, easy, safe and effective torquing technique, termed Park’s cervical torque tie, has been devised. A female patient sought orthodontic treatment and presented...

Objective: This study aimed to clarify differences in the positions of cone-beam computed tomography (CBCT) landmarks according to different midsagittal planes (MSPs) in patients with skeletal Class III facial asymmetry. Methods: Pre-treatment CBCT data from 60 patients with skeletal Class III were used. The patients were classified into symmetr...

Introduction: This study aimed to determine the minimum required length of microimplants (MIs) to prevent excessive micromotion during MI healing that can lead to MI failure. Methods: Hypothesizing that the implantation depth of MI in cancellous bone (IDcancel) is the key to the control of micromotion during MI healing, we numerically investigat...

Objectives To compare a novel body mandibular horizontal plane (mental foramen–protuberance menti; Body-MHP) with the conventional border mandibular horizontal plane (gonion–menton [Me]; Border-MHP) to assess mandibular body inclination and dental compensation of skeletal Class III patients with and without facial asymmetry. Materials and Methods...

Recently, the demand for correcting facial asymmetry has been increasing, even when the extent of asymmetry is small. This case report describes nonsurgical orthodontic treatment for facial asymmetry in a 13-year-old female patient, facilitated by moving the deviant mandible to the nondeviated side after correcting for relevant dental compensation...

Background: Skeletal anchorage has made it possible to perform complex orthodontic tooth movements that are difficult or even impossible to achieve with conventional orthodontic treatment. Mandibular buccal shelf miniscrews, used for distalization, play a particularly important role in treatment of Class III malocclusion. Unfortunately, stability...

Objective: To compare the removal torque of microimplants upon post-use removal and post-retention removal and to assess the influencing factors. Methods: The sample group included 241 patients (age, 30.25 ± 12.2 years) with 568 microimplants. They were divided into the post-use (microimplants removed immediately after use or treatment) and post...

Introduction: 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. Methods: The insertion of a standard size mini-implant (φ 1.4 mm × 7 mm) into ma...

Severe mandibular deficiency caused by temporomandibular joint (TMJ) ankyloses produces functional and aesthetic problems that require complicated long-term treatment. In this case report, we describe the benefits of using microimplant mechanics for controlling the direction of distraction during distraction osteogenesis and for performing the move...

Background The current study aimed to evaluate factors affecting the long-term stability of microimplants using removal torque and the correlation between removal torque and clinical variables. Materials and methods This research evaluated 703 microimplants placed in 354 patients (mean age: 30.4 ± 12.1 years). The removal torque was evaluated acco...

Introduction This study aimed to evaluate maxillary skeletal and dental yaw in patients with skeletal Class III facial asymmetry and investigate its correlation with menton deviation. Methods Initial cone-beam computed tomography data from 60 patients with skeletal Class III malocclusion were used. There were 30 patients in both the symmetrical gr...

WANG, S.; BING, L. & PARK, H. S. Optimal microimplant sites in the mandibular retromolar area: Mesh analysis of cortical bone thickness and density in CBCT images. Int. J. Morphol., 39(3):907-914, 2021. SUMMARY: This study was performed to identify optimal microimplant sites in the mandibular retromolar area by measurement and analysis of cortical...

In clinical orthodontic practice, fixed brackets are widely used for tooth movement and adjustments. Although years of research and development have improved the workability of fixed orthodontic brackets, there are still controversies regarding its plausible destructive influence on the enamel surface of tooth. This, in turn, makes the quantitative...

Idiopathic condylar resorption (ICR) is a rare, destructive temporomandibular joint disease characterised by progressive resorption of the condyles. This case report presents a record of an orthodontically treated patient with ICR with favourable posttreatment remodelling of the condyles. An 18-year-old woman sought treatment for ICR. A severe Clas...

Objective: To investigate the prevalence of malocclusion with respect to grade, sex, and year among Korean pre-adolescent and adolescent students during 2012-2017. Methods: A total of 165,996 students (first grade [E1, 6-7 years of age], fourth grade [E4, 9-10 years], seventh grade [M1, 12-13 years], and tenth grade [H1, 15-16 years]) were selec...

Background. Predicting the cooperation of orthodontic patients seems to be of the utmost importance for successful results in treatment with removable appliances, especially if their cost is to be covered from public funding. Therefore, the issue of unbiased pre-treatment assessment of cooperation still calls for an investigation.

The article shows the accelerated protraction of lower second molar with microimplant anchorage by delaying extraction of mesial root of first molar. The procedure could decrease soft tissue cleft and preserve bone volume.

Introduction: The purpose of this research was to evaluate dental compensation in facial asymmetry and its correlation with skeletal variables using cone-beam computed tomography. Methods: Sixty adult patients were retrospectively divided into asymmetry (mean age, 21.8 ± 5.4 years) and symmetry groups (mean age, 28.1 ± 4.1 years); both groups co...

This article shows real visual anatomical limitation of distalization of the lower molars in nonextraction treatment. The distal roots of the lower second molars were pushed to the lingual cortical bone plate and this deterred distal movement of the teeth, and produced distal and buccal tipping of the lower second molars.

Background and overview: The authors describe a bracket-free forced eruption technique using microimplants that does not require patient compliance and report relapse after long-term observation. Case description: In 2 patients who needed to undergo forced eruption of carious and fractured roots of anterior teeth, the authors erupted the roots f...

Bonding of braces is an essential part in contemporary orthodontic treatment. For the proper strength of bracket bonding, enamel conditioning or surface treatment on tooth surface is required. Treatment on the tooth surface such as prophylaxis smoothing with pumice and enamel etching results in considerable damages to the enamel surface of the toot...

Microimplants are being used extensively in clinical practice to achieve absolute anchorage. Success of microimplant mainly depend on its primary stability onto the cortical bone surface and the associated Microdamage of the cortical bone during insertion procedure leads to many a microimplants to fail and dislodge from the cortical bone leading to...

This chapter dealt with factors affecting facial profile in treatment of hyperdivergent patients with microimplant anchorage and presented a case treated with microimplants

Objectives: The study was done to evaluate the efficacy of optical coherence tomography (OCT), to detect and analyze the microdamage occurring around the microimplant immediately following its placement, and to compare the findings with micro-computed tomography (μCT) images of the samples to validate the result of the present study. Methods: Mi...

Cone Beam Computed Tomography (CBCT) measurement of cortical bone thickness and implantation angle in the maxillary posterior region was used to provide reference for the safety of Micro-Implanted-Anchorage (MIA) implantation in skeletal class II malocclusion. Twenty samples of CBCT images were collected from orthodontics patients (ages, 12-40 year...

Objectives: To observe the surface characteristics and mechanical behavior of retrieved microimplants under clinically simulating experimental conditions and to investigate the feasibility of reuse of microimplants. Materials and methods: The microimplants, inserted at different angles, were retrieved from the patients (RMIP) and the artificial...

Palatal plane cant and protrusion of roots into maxillary sinus W e praise the authors of the article entitled "Differ-ences in distances between maxillary posterior root apices and the sinus floor according to skeletal pattern" in the December 2017 issue (Ahn NL, Park HS. Am J Or-thod Dentofacial Orthop. 2017; 152:811-9) for their involvement in e...

Introduction: The aim of this study was to evaluate the distances from the maxillary posterior root apices to the inferior wall of the maxillary sinus using cone-beam computed tomography images and the relationships between roots and maxillary sinus according to age, sex, and skeletal pattern. Methods: Three-dimensional images of each root were...

This paper presents an overview of the current knowledge about non-invasive investigations using optical coherence tomography (OCT) – structural imaging of oral tissues and biomaterials applied in vivo and in vitro – employed in the field of orthodontics. Optical coherence tomography is an emerging technology for producing high-resolution cross-sec...

The book described many clinical application of microimplants.

The book dealt with treatment of extraction orthodontic treatment with microimplants and biomechanics, detalied procedure of surgical placement of microimplants.

The book describe the treatment of group distalization, deepbite, openbite, Class III malocclusion with microimplant, and the use of microimplants in minor tooth movement.

The book describe the use of microimplants in orthognathic surgery, for decompensation, jaw bone stabilization after surgery, correction of surgical errors just after surgery, completion of occlusion during post-surgical orthodontic treatment.

Summary OBJECTIVE : To test the null hypothesis that neither the flexural properties of orthodontic adhesive resins nor the enamel pre-treatment methods would affect metal bracket debonding behaviours, including enamel fracture. A dimethacrylate-based resin (Transbond XT, TX) and two methyl methacrylate (MMA)-based resins (Super-Bond C&B, SB; an ex...

The purpose of this study was to evaluate the soft tissue changes and skeletal stability of a modification of the Le Fort I osteotomy design - the modified quadrangular Le Fort I osteotomy (MQLI). Patients who had maxillary advancement and mandibular setback surgery for skeletal class III malocclusion with a midface deficiency were included. MQLI p...

Objective: To analyze the influence of the length of temporary intraoral skeletal anchorage devices (TISAD/TAD) on their long-term stability in the mandible in a homogenous group of patients. Materials and methods: A group of generally healthy patients of the same gender (female) and with a statistically insignificant age difference (20-29 years...

The purpose of this study was to compare the accuracy of maxillary repositioning using the recently introduced computerized virtual model surgery (VMS) with conventional articulator model surgery (AMS). Forty-two patients who had undergone bimaxillary surgery were investigated retrospectively in this study. The patients were divided into two groups...

Objective: To test the hypothesis that there are no differences in mutans streptococci (MS) adhesion between esthetic and metallic orthodontic arch wires based on their surface characteristics. Materials and methods: Surface roughness (Ra) and apparent surface free energy (SFE) were measured for six wires-four esthetic, one nickel-titanium (NiTi...

The purpose of this study was to compare stability after mandibular setback surgery in patients with skeletal Class III malocclusion with and without presurgical orthodontics. This retrospective cohort study included consecutive patients with skeletal Class III malocclusion who underwent only mandibular surgery. Patients treated with the surgery-fi...

Introduction Interactive Approaches Holding the Molar Vertical Position Intrusion of Molars Molar Uprighting Forced Eruption Surgical Placement of Micro-Implants Conclusion References

Persistent macroglossia affects speech, swallowing, and the dentofacial skeleton. A range of tongue reduction methods have been proposed to preserve the mobility and sensation of the tongue. However, recent reports have shown that speech or esthetic problems still exists, even after a comprehensive glossectomy in early childhood. Because a large vo...

The aim of this study was to evaluate the stress state in the cortical bone around an orthodontic microimplant during and after the insertion surgery. The self-tapping insertion of an orthodontic microimplant into 1-mm-thick cortical bone containing a predrilled hole was simulated by using a 3-dimensional finite element method. The entire insertion...

The chapter described the varous method of using microimplants in minor tooth movement.

Objective: We compared the shear bond strength (SBS) of lingual retainers bonded to bovine enamel with three different resins using direct and indirect methods. Methods: Both ends of pre-fabricated twisted ligature wires were bonded to bovine enamel surfaces using Light-Core, Tetric N-Flow, or Transbond XT. Phosphoric acid-etched enamel surfaces we...

Structural characteristics of the pterygomaxillary region in patients with cleft lip and palate (CLP) have not been fully investigated. This study aimed to evaluate the regional anatomy of the pterygomaxillary junction of patients with CLP using computed tomography. The pterygomaxillary structures of patients with unilateral or bilateral CLP were c...

Objective: Microscrew implants (MSIs) offer many advantages, but some complications are known to occur during their insertion. One of the most commonly reported complications is root injury. Our aim was to identify factors associated with root injury and to evaluate their qualitative and quantitative values. Methods: Thirty-five orthodontists place...

Our objective was to quantify the treatment effects of microimplant-aided mechanics on group distal retraction of the posterior teeth. The pretreatment and posttreatment cephalometric radiographs and dental casts of 23 patients (mean age, 22.1 ± 5.17 years), treated with distalization of the posterior teeth against microimplant anchorage and withou...

The goal of this report was to illustrate new treatment mechanics for using microimplants for the treatment of a Class II Division 2 deepbite malocclusion. A 29-year-old woman with a deepbite was treated with the aid of microimplant anchorage. Microimplants placed between the maxillary second premolars and first molars were used as anchorage to app...

To examine the effect of garlic extract on the biofilm formation by Streptococcus mutans on orthodontic wire and on glucosyltransferase gene expression. Growth inhibition of oral bacteria was tested after 50 µL of garlic extract was placed on an agar plate. The minimum inhibitory concentration (MIC) of garlic extract on S mutans growth was first de...

The purpose of this study was to optimize the thread pattern of orthodontic microimplants. Methods: In search of an optimal thread for orthodontic microimplants, an objective function stability quotient (SQ) was built and solved which will help increase the stability and torsional strength of microimplants while reducing the bone damage during inse...

The aim of this study was to evaluate the biomechanical aspects of peri-implant bone upon root contact of orthodontic microimplant. Me thods: Axisymmetric finite element modeling scheme was used to analyze the compressive strength of the orthodontic microimplant (Absoanchor SH1312-7, Dentos Inc., Daegu, Korea) placed into inter-radicular bone cover...

While the soluble proteins of human teeth consist of various extracellular matrix and bioactive proteins, they have not yet been characterized fully. Moreover, the role they play in tooth regeneration is not clear. Analysis of the soluble proteins in human teeth by liquid chromatography-mass spectrometry revealed 147 different ethylenediaminetetraa...

JCO recently polled a number of editors and other prominent orthodontists who have considerable experience working with skeletal anchorage. The question was: "In your experience, what are the most important factors determining success or failure with skeletal anchorage, and why?" Here are their replies.

To increase stability and mandibular setback movement, surgical maxillary impaction is normally performed with mandibular setback surgery in treating adult skeletal Class III patients. This article demonstrates the use of microimplants for anchorage to intrude molars and the resultant rotation of the maxillary occlusal plane clockwise to increase t...

A Le Fort I osteotomy is widely used to correct dentofacial deformity because it is a safe and reliable surgical method. Although rare, various complications have been reported in relation to pterygomaxillary separation. Cranial nerve damage is one of the serious complications that can occur after Le Fort I osteotomy. In this report, a 19-year-old...

To provide information about placement sites and angulations of microimplants between tooth roots, we analyzed 3-dimensional computed tomography images from 25 patients. The patients in the sample had good interdigitation, no restorations, and no arch length discrepancies in the posterior segments. Three-dimensional images of the maxillary and mand...

Anchorage control is important for efficient orthodontic treatment with fixed appliances. Successful osseointegration encouraged many orthodontists to use dental implants as stationary anchorage units for force application. However, their use has some drawbacks, which led to the development of miniscrew implants (MIs). Our aim was to investigate fa...

INTRODUCTION: Anchorage control is important for efficient orthodontic treatment with fixed appliances. Successful osseointegration encouraged many orthodontists to use dental implants as stationary anchorage units for force application. However, their use has some drawbacks, which led to the development of miniscrew implants (MIs). Our aim was to...

The book describe the use of microimplants in molar intrusion, molar uprighting, forced euptuion, molar protraction.

To test the bonding characteristics of four flowable composites for orthodontic bracket bonding. Metal brackets were bonded to acid-etched human enamel using four flowable composites (Grandio Flow, GF; UniFil Flow, UF; UniFil LoFlo Plus, UL; and DenFil Flow, DF), an orthodontic bonding system (Transbond XT, TX), and a restorative composite (Filtek...

Objective: The aim of this study was to evaluate the potency of panoramic radiography for the detection of maxillary impacted canines. Methods: Twenty-five patients were selected, comprised of 7 males (mean age: 10.9 years, range: 8.5 - 14.5 years) and 18 females (mean age: 10.9 years, range: 8.2 - 15.7 years). In total, thirty-five maxillary impac...

This study provides the first demonstration that central cannabinoids modulate the antinociceptive actions of metabotropic glutamate receptors (mGluRs) on formalin-induced temporomandibular joint (TMJ) nociception. Noxious scratching behavior induced by formalin injection in the TMJ was used as a model of pain. Intracisternal injection of 30mug of...

Objective: The purpose of this study was to compare the cephalometric measurements of obese and non-obese Korean male patients with obstructive sleep apnea syndrome (OSA). Methods: Eighty-seven adults who had visited the Sleep Disorder Clinic Center in Keimyung University, Daegu, Korea were examined and evaluated with polysomnography (PSG) and late...

The purposes of this study were to quantify the treatment effects of titanium screws on en-masse retraction of 6 anterior teeth and to compare the anchorage potential of treatment with titanium screws with the Tweed-Merrifield technique, which requires patient compliance with a high-pull J-hook. Sixteen nongrowing patients (14 women, 2 men; ages, 2...