• The Journal of the Korean dental association
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• v.45 no.8 s.459
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• pp.483-490
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• 2007

The aim of this study was to investigate the relationship between the mandibular antegonial notch and the mandibular morphology, and the curve of Spee in anteroposterior skeletal relationship. Pre-treatment lateral cephalograms were obtained from 80(male 34, female 46) adult orthodontic patients and the samples were classified into 3 categories by ANB angle($0^{\circ}$$\leq$ANB< $4^{\circ}$ Class I, $4^{\circ}$$\leq$ANB Class II, ANB< $0^{\circ}$ Class III). The curve of Spee was measured directly from the pre-treatment mandibular study cast of each patient included in this study. Pearson correlation coefficient test and multiple regression analysis in each group revealed the following results; 1. Antegonial notch depth was positively correlated with hoth lower anterior facial height(ANS-Me) in skeletal Class I, II and III groups and Id-Me height in skeletal Class I and II groups. 2. A statistically significant negative correlation was found between the depth of the antegonial notch and the curve of Spee in the Class III group. 3. Significant relationship was not found between the antegonial notch depth and any of the other cephalometric variables such as mandibular body length(Go-Gn) and ramus height(Co-Go). As antegonial notch depth increased, more vertical growth of the mandible was observed. Antegonial notch can be used as a predictor of vertical mandibular growth in the diagnosis and treatment planning of malocclusion.

• Journal of Korean society of Dental Hygiene
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• v.18 no.2
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• pp.227-237
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• 2018

Objectives: This study aims to recognize the importance of dental hygiene process diagnosis of dental hygiene process which can comprehensively grasp the patient's problem and to use it as a basis for establishing the patient's preventive treatment plan. Methods: This study did survey to 443 patients who received treatment based on the oral health care program from a dental clinic in Busan from January 2015 to January 2017. Data analysis was performed using IBM SPSS Statistics (Version 21.0), and statistical significance level was set at ${\alpha}=0.05$. Binary logistic regression analysis was performed to the dental hygiene problems affecting the dental hygiene plan. Results: There were significant differences in dental hygiene problems between male and female respondents on various dental problems such as dental plaque deposition, attrition, stain, dental fear, possibility of jaw joint disorder, food pressing, possibility of malocclusion. There were also significant differences in dental hygiene plans between male and female respondents in air-Jet, non-smoking education, and sealant. The most common dental hygiene plan was scaling, The problem of stain showed that the scaling plan was 0.20 times less. The explanatory power of the model was 43.5%, and the Hosmer and Lemeshow tests were 0.345. Conclusions: Therefore, if we continue to study the factors affecting the dental hygiene problems and the plan, we can reduce the burden of the dental hygienists applying the dental hygiene process in the dental clinic. And, it is expected that the oral health care program using the dental hygiene process will spread to the dental clinic as an excellent oral preventive program.

• Journal of Veterinary Clinics
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• v.30 no.2
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• pp.127-130
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• 2013

A 13-year-old, 4.2 kg female poodle was referred for failure of first bilateral mandibular surgery at a local animal hospital after pathologic fracture. Surgery was performed with 2.0-mm miniplates/screws and porcine cancellous bone grafts. In addition, because of the large size of the right segmental defect, a barrier absorbable membrane was employed for guide bone regeneration on right mandible. After surgery, follow-ups performed at 1 day, 1, 4, 8, and 12 weeks; there were no signs of dental malocclusion, nonunion or soft tissue infection. However, a 1-year long-term follow-up showed nonunion in the left mandibular fracture site for which a collagen membrane had not been used. It is considered that use of porcine bone graft with barrier absorbable membrane may be effective for the repair of mandibular nonunion in a geriatric dog.

• Archives of Craniofacial Surgery
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• v.12 no.2
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• pp.102-106
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• 2011

Purpose: It is accepted universally that correction of the cleft lip nasal deformity requires multiple stages of surgery. Following primary lip repair in infancy or early childhood, secondary surgery to improve the deformity of the lip and nose is frequently necessary. A suitable surgical procedure to correct the accompanying deformity, such as cleft palate and alveolus, must be carried out at an appropriate age. In developing countries, it is common for patients with cleft lip nasal deformity to present severe secondary deformities in adolescence, because of poor follow-up and inappropriate surgery. Methods: The first patient was a 12 year old Mongolian boy. He presented prominent lip scar, short lip, wide columella, asymmetric nostril, palatal fistula, cleft alveolus, and velopharyngeal incompetence. He underwent cheilorhinoplasty, transpositional flap, alveoloplasty by iliac bone graft, and sphincter pharyngoplasty. On follow-up, a bilateral maxillary hypoplasia and a class III malocclusion developed. He underwent LeFort I osteotomy and maxillary advancement at the age of 16 years. The second patient was an 18 year old Eastern Russian girl. She presented with a deviated nose, right alar base depression, short lip, protrusion on vermilion, large palatal fistula, and severe VPI due to short palate. She underwent the combined procedure of cheilorhinoplasty, corrective rhinoplasty, tongue flap for palatal fistula, and superiorly based pharyngeal flap. And the tongue flap was detached at postoperative 3 weeks. Results: The overall results have been extremely pleasing and satisfactory to patients. There were no postoperative complications. Conclusion: We discovered the one stage operation for radical correction was sufficient procedure to provide excellent clinical outcomes in patients with severe cleft lip nose deformity.

• Journal of the Korea Convergence Society
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• v.12 no.10
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• pp.89-96
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• 2021

This study is aimed to establish the direction of orthodontic treatment by analyzing the differences in the dental arch development due to the cause of short stature. Dental diagnostic tests were conducted on patients who were diagnosed with short stature. Idiopathic short statured children were classified through the paired sampling based on the age and gender of a short statured children with growth hormone shortage. Control groups were classified using same method as above, after selecting candidates with an arch length of less than 3mm and malocclusion. In conclusion, short statured children with growth hormone shortage or idiopathic had the higher rate of crowding and the small value of overbite compared to normal children. Therefore orthodontic treatment for short statured children needs treatment plan included evaluation for Arch length discrepancy to treat a crowding early. This study will provide important data for successful orthodontic treatment according to the characteristics of dental occlusion of short statured children.

• The korean journal of orthodontics
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• v.49 no.1
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• pp.49-58
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• 2019

Objective: The aim of this retrospective study was to evaluate and compare the changes in the pharyngeal airway (PA), maxillary sinus volume, and skeletal parameters after rapid maxillary expansion (RME) and alternate rapid maxillary expansion and constriction (Alt-RAMEC) followed by facemask (FM) therapy. Methods: The records of 40 patients with skeletal Class III malocclusion due to maxillary retrognathism were collected, and the patients were assigned into two groups. The first group comprised 8 male and 12 female patients (mean age, $10.0{\pm}1.1years$) treated using RME/FM for an average of 10 months. The second group comprised 10 male and 10 female patients (mean age, $9.64{\pm}1.3years$) treated using Alt-RAMEC/FM for an average of 12 months. Cone-beam computed tomography images acquired before (T0) and after treatment (T1) were evaluated. Results: Regarding the skeletal effects, significant differences between the groups were the increase in ANS-HRP (perpendicular distance of ANS to the horizontal reference plane, 0.99 mm, p <0.05) in the Alt-RAMEC/FM group and the decrease in PP-SN (palatal plane to Sella-Nasion plane, $0.93^{\circ}$, p < 0.05) in the RME/FM group. Maxillary sinus volumes increased significantly in both the groups, and the increase was statistically significantly higher in the Alt-RAMEC/FM group. Although no significant intergroup differences were observed in PA volumes, both lower ($1,011.19mm^3$) and total ($1,601.21mm^3$), PA volume increased significantly in the Alt-RAMEC/FM group. Conclusions: The different expansion devices and protocols used with FM therapy do not seem to affect the forward movement of the maxilla and PA volumes. In contrast, the increase in maxillary sinus volume was greater in the Alt-RAMEC/FM protocol.

• The Korean Journal of Oral and Maxillofacial Pathology
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• v.42 no.6
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• pp.159-165
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• 2018

The Hippo pathway was originally discovered in Drosophila by genetic screening and it has been shown to be conserved in various organisms including human. Until now, the essential roles of Hippo pathway in regulating cell proliferation, apoptosis, tumorigenesis, and organ size control is extensively studied. Currently, Mats1/2 (Mob1a/1b), one of the important components in Hippo pathway, mutant mice were generated which has abnormal phenotype such as resistance to apoptosis and spontaneous tumorigenesis. Of note, Mats1/2 mutant mice also showed dental malocclusion. Therefore, in this study, we have evaluated the bone phenotype of Mats1/2 mutant mice. Although the mRNA expressions of Mats1 or Mats2 were observed in both osteoclastogenesis and osteoblastogenesis, the increase of Mats1 level was most prominent during osteoblastogenesis. The RANKL-induced osteoclast differentiation from bone marrow-derived macrophages (BMMs) was unaltered upon Mats1/2 mutation; however, the osteoblast differentiation using calvarial pre-osteoblasts was significantly reduced in Mats1/2 mutant mice compare to that of wild type mice. In accordance with in vitro results, Mats1/2 mutant mice showed decreased bone volume as well as increased trabecular separation in ${\mu}CT$ analyses. These results may provide novel prospect of the probable linkage between Hippo pathway and bone homeostasis.

• The korean journal of orthodontics
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• v.49 no.5
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• pp.319-325
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• 2019

Objective: To evaluate differences in skeletal maturity in relation to vertical facial types and to compare differences in the skeletal maturity of the cervical vertebrae and hand-wrist in females. Methods: This study included 59 females aged 7 to 9 years with skeletal Class I malocclusion. The participants were categorized into three groups (low, normal, and high) according to the mandibular plane angle. Skeletal maturity was measured using skeletal maturity indicators (SMIs) and the Tanner-Whitehouse III (TW3) method on hand-wrist radiographs and by using cervical vertebrae maturation indicators (CVMIs) on lateral cephalometric radiographs. Results: The SMI was higher in the high-angle group than in the low-angle group (p = 0.014). The median TW3 bone age was 11.4 months higher in the high-angle group than in the low-angle group (p = 0.032). There was no significant difference in CVMI among the three groups. Skeletal maturity showed a weakly positive correlation with the mandibular plane angle (SMI, r = 0.391; TW3, r = 0.333; CVMI, r = 0.259). Conclusions: The skeletal maturity of the hand-wrist in females with a high mandibular plane angle was higher than that in females with a low mandibular plane angle. Obtaining additional hand-wrist radiographs may facilitate evaluation of skeletal maturity of females. In females with a high mandibular angle, the time to commence orthodontic treatment may be earlier than that in females with a low mandibular angle.

• The korean journal of orthodontics
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• v.49 no.5
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• pp.279-285
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• 2019

Objective: This study evaluated the efficiency of anchorage provided by temporary anchorage devices (TADs) in maxillary bicuspid extraction cases during retraction of the anterior teeth using a fixed appliance. Methods: Patients aged 12 to 50 years with malocclusion for which bilateral first or second maxillary bicuspid extractions were indicated were included in the study and randomly allocated to the TAD or control groups. Retraction of the anterior teeth was achieved using skeletal anchorage in the TAD group and conventional dental anchorage in the control group. A computed tomography (CT) scan was performed after alignment of teeth, and a second CT scan was performed at the end of extraction space closure in both groups. A three-dimensional superimposition was performed to visualize and quantify the maxillary first molar movement during the retraction phase, which was the primary outcome, and the stability of TAD movement, which served as the secondary outcome. Results: Thirty-four patients (17 in each group) underwent the final analysis. The two groups showed a significant difference in the movement of the first maxillary molars, with less significant anchorage loss in the TAD group than that in the control group. In addition, TAD movement showed only a slight mesial movement on the labial side. On the palatal side, the mesial TAD movement was greater. Conclusions: In comparison with conventional dental anchorage, TADs can be considered an efficient source of anchorage during retraction of maxillary anterior teeth. TADs remain stable when correctly placed in the bone during the anterior tooth retraction phase.

• Imaging Science in Dentistry
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• v.49 no.2
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• pp.159-169
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• 2019

Purpose: Cone-beam computed tomography (CBCT) is widely used for 3-dimensional assessments of cranio-maxillo-facial relationships, especially in patients undergoing orthognathic surgery. We have introduced, for reference in CBCT cephalometry, an anatomical mid-sagittal plane (MSP) identified by the nasion, the midpoint between the posterior clinoid processes of the sella turcica, and the basion. The MSP is an updated version of the median plane previously used at our institution for 2D posterior-anterior cephalometry. This study was conducted to test the accuracy of the CBCT measures compared to those obtained using standard posterior-anterior cephalometry. Materials and Methods: Two operators measured the inter-zygomatic distance on 15 CBCT scans using the MSP as a reference plane, and the CBCT measurements were compared with measurements made on patients' posterior-anterior cephalograms. The statistical analysis evaluated the absolute and percentage differences between the 3D and 2D measurements. Results: As demonstrated by the absolute mean difference (roughly 1 mm) and the percentage difference (less than 3%), the MSP showed good accuracy on CBCT compared to the 2D plane, especially for measurements of the left side. However, the CBCT measurements showed a high standard deviation, indicating major variability and low precision. Conclusion: The anatomical MSP can be used as a reliable reference plane for transverse measurements in 3D cephalometry in cases of symmetrical or asymmetrical malocclusion. In patients who suffer from distortions of the skull base, the identification of landmarks might be difficult and the MSP could be unreliable. Becoming familiar with the relevant software could reduce errors and improve reliability.