• 대한치과교정학회:학술대회논문집
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• 2002.11a
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• pp.88.2-89
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• 2002

• 대한치과교정학회:학술대회논문집
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• 2000.11a
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• pp.25.2-27
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• 2000

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.5
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• pp.407-412
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• 2011

Purpose: The purpose of the present study was to evaluate the postoperative skeletal stability of two-jaw surgery (Le Fort I osteotomy and bilateral sagittal split ramus osteotomy) via surgery first orthodontic treatment (SFOT) in class III malocclusion. Methods: Thirty-two patients who had two-jaw surgery via SFOT were included in this study. Serial lateral cephalograms were obtained before (T0), immediately after (T1), and six months after (T2) surgery. Twelve variables were measured for horizontal and vertical skeletal stability as well as for dental change. All measurements were evaluated statistically by a paired t-test ($P$ <0.05). Results: The mean skeletal changes were $0.1{\pm}2.5$ mm at point A and $-12.0{\pm}7.4$ mm at the pogonion. The mean horizontal relapse was 11.6% at the pogonion, and the mean vertical surgical changes included an upward displacement of $2.1{\pm}7.1$ mm and a forward displacement of $1.4{\pm}4.6$ mm at the pogonion. Upper incisor inclination decreased after surgery and was maintained at T2, and lower incisors were proclined from T1 to T2 by postsurgical orthodontic treatment. Conclusion: Postoperative skeletal stability of two-jaw surgery via surgery first orthodontic treatment in class III malocclusion was clinically acceptable.

• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.1
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• pp.32-37
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• 1999

Twin blocks are bite-blocks that effectively modify the occlusal inclined plane to induce favorably directed occlusal forces by causing a functional mandibular displacement. One of the advantage is that full-time wear can be possible because of less interference with normal function such as eating and speaking. So rapid correction of malocclusion is expected. Reverse twin block appliance is modification for correction of class III malocclusion with sagittal component. For increased growth stimulation effort on premaxilla, lip pads can be added. But with lip pads, patients are incapable of full-time wear especially during mealtime. So, removable lip pads can be used for stimulation of growth on premaxilla without any restriction of function. The advantages of the reverse twin block appliance with removable lip pads are: 1. Full-time wear is possible (including mealtime). 2. Patients' cooperation and adaptation is excellent. 3. There is no period of dual bite. 4. Orthopedic correction is achieved by multiple modes, shortening the treatment time. The applied case shows that the reverse twin block appliance with removable lip pads is effective for treatment of class III malocclusion and can shorten the time of treatment.

• The korean journal of orthodontics
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• v.25 no.6 s.53
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• pp.675-688
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• 1995

The purposes of this study were:1) to determine the normal range of CR-CO discrepancy in normal occlusion group ; 2) to evaluate the changes of condylar position and craniofacial morphology between centric relation and centric occlusion before and after stabilization splint therapy in malocclusion group outside the normal range of CR-CO discrepancy. The normal occlusion group consisted of 80 subjects who had well-balanced faces and good occlusions with acceptable Class I molar relationship. They had not been treated orthodontically and had no signs or symptoms of temporomandibular joint dysfunction. 71 malocclusion patients enrolled for orthodontic treatment at the Department of Orthodontics, College of Dentistry, Chosun University comprised the malocclusion group, little variation of growth factor by the second molar eruption. They had CR-CO discrepancy beyond normal range and were subdivided into anterior-posteriorly -[25 Class I (0$\geq$4), and 24 Class III (ANB$\leq$0)] : vertically - [20 Normodivergentscy (30$\geq$34), and 18 Hypodivergency (SNGoMe$\leq$30)] ; and sexually - [26 Male and 45 Female]. For malocclusion group, stabilization splint with mutually protected type of occlusal scheme was applied for three months. Panadent articulators, Panadent condylar position indicator (CPI), and lateral headfilm were used to investigate the influence of stabilization splint on condylar position and craniofacial morphology. The results of this study were as follows. 1. The amounts of CR-CO discrepancy in normal occlusion were that the antero-Posterior component (${\bigtriangledown}X$) was $0.56\pm0.46mm$ (Male:$0.63\pm0.42mm$, Female:$0.49\pm0.50mm$) ; the supero-inferior component (${\bigtriangledown}Y$) was $-0.75\pm0.48mm$ (Male:$-0.76\pm0.52mm$, Female:-$0.73\pm0.43mm$) : and the transverse component (${\bigtriangledown}Z$) was $-0.33\pm0.28mm$ (Male : $-0.38\pm0.29mm$, Female:$-0.31\pm0.27mm$). 2. The condylar position was in normal range after stabilization splint therapy. 3. The mandible was always rotated infero-posteriorly after stabilization splint therapy. 4. Antero-posteriorly, Class III malocclusion responded very well to the stabilization splint therapy. 5. Vertically, Hyperdivergency responded very well to the stabilization splint therapy 6. Sexually, Male responded very well to the stabilization splint therapy.

• The korean journal of orthodontics
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• v.33 no.1 s.96
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• pp.31-39
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• 2003

This study was performed to evaluate whether growth Prediction method can be used to diagnose and make treatment plan in skeletal Class III malocclusion patients or not. The sample was consisted of 25 patients(13 males, 12 females) who had been diagnosed with skeletal Class III malocclusion at first visit and after that had returned to take ortognathic surgery. Growth prediction performed with Ricketts' growth prediction method from first cephaogram. was compared with actual growth of the second cephalogram. The findings of this study were as follows ; 1. There was significant difference between actual growth and growth prediction in Porion Location, Ramus Position, Facial Depth, Facial Axis, Mandibular Plane angle, Maxillary Convexity. So, for these items Ricketts' growth prediction method is not proper to predict growth. 2. Although the growth amount of mandibular body was similar to normal growth amount, mandible was positioned anteriorly because of Porion Location and Ramus Position. 3. In skeletal Class III malocclusion patients, the tendency of mandibular prognathism might be aggreviated because of anterior placement of ramus and anterosuperior rotation of Pogonion.

• The korean journal of orthodontics
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• v.43 no.5
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• pp.209-217
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• 2013

Objective: This study investigated whether temporomandibular joint (TMJ) condyle-fossa relationships are bilaterally symmetric in class III malocclusion patients with and without asymmetry and compared to those with normal occlusion. The hypothesis was a difference in condyle-fossa relationships exists in asymmetric patients. Methods: Group 1 comprised 40 Korean normal occlusion subjects. Groups 2 and 3 comprised patients diagnosed with skeletal class III malocclusion, who were grouped according to the presence of mandibular asymmetry: Group 2 included symmetric mandibles, while group 3 included asymmetric mandibles. Pretreatment three-dimensional cone-beam computed tomography (3D CBCT) images were obtained. Right- and left-sided TMJ spaces in groups 1 and 2 or deviated and non-deviated sides in group 3 were evaluated, and the axial condylar angle was compared. Results: The TMJ spaces demonstrated no significant bilateral differences in any group. Only group 3 had slightly narrower superior spaces (p < 0.001). The axial condylar angles between group 1 and 2 were not significant. However, group 3 showed a statistically significant bilateral difference (p < 0.001); toward the deviated side, the axial condylar angle was steeper. Conclusions: Even in the asymmetric group, the TMJ spaces were similar between deviated and non-deviated sides, indicating a bilateral condyle-fossa relationship in patients with asymmetry that may be as symmetrical as that in patients with symmetry. However, the axial condylar angle had bilateral differences only in asymmetric groups. The mean TMJ space value and the bilateral difference may be used for evaluating condyle-fossa relationships with CBCT.

• The korean journal of orthodontics
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• v.44 no.3
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• pp.136-142
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• 2014

Objective: To evaluate the active-treatment effects of the Forsus fatigue resistant device (Forsus) during comprehensive correction of Class II malocclusion in growing patients. Methods: Fifty-four patients (mean age, $12.5{\pm}1.2$ years) with Class II division 1 malocclusion were consecutively treated with fixed app-liances in combination with Forsus. Lateral cephalograms were analyzed at the beginning of the fixed treatment (T1), Forsus insertion (T2), its removal (T3), and end of the comprehensive therapy (T4). Statistical comparisons were carried out by repeated-measures ANOVA with Tukey's post-hoc test (p < 0.05). Results: The overall therapeutic effects were mainly dentoalveolar and occurred mostly during the active treatment with Forsus (T2-T3, mean duration = $0.5{\pm}0.1$ years). The overjet and overbite decreased significantly (-3.5 and -1.5 mm, respectively) and the molar relationship improved by 4.3 mm. These changes were associated with significant retroclination of the maxillary incisors ($-3.1^{\circ}$), proclination and intrusion of the mandibular incisors ($+5.0^{\circ}$ and -1.5 mm, respectively), and mesialization of the mandibular molars (+2.0 mm). Conclusions: Forsus had mainly dentoalveolar effects and contributed largely to the overall therapeutic outcome.

• The korean journal of orthodontics
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• v.34 no.2 s.103
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• pp.109-119
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• 2004

This study aimed at investigating the skeletal, dentoalveolar, and soft tissue changes of Class III malocclusion cases treated by second molar extraction. The lateral cephalograms of 15 subjects with moderate Class III malocclusion by average ANB $-1.4^{\circ}\;and\;IMPA\;85^{\circ}$ were traced and the computerized superimposition of average craniofacial change was made. The data was gathered and statistically analyzed. The results were as follows: 1 Lower anterior facial height/anterior facial height increased by 0.6%(P<0.01), mandibular plane increased by $1.5^{\circ}$(P<0.05). 2. There was a slightly downward & backward rotation of the mandible. 3. Lower first molar tipped distally by 4.nm(P<0.001), lower anterior teeth lingually tipped by $3.2^{\circ}$(P<0.05). 4. Retracted lower lip improved facial profile. This study may suggest that second molar extraction could be effective for a moderate Class III malocclusion to make distalization of the lower first molar easier and avoid severe lingual tipping of the lower incisor, if the lower third molar has a normal shape, good direction of eruption and adequate time for lower second molar extraction

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.1
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• pp.29-40
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• 2008

The purpose of this study was to evaluate the prevalence of symptoms and signs of temporomandibular joint dysfunction (TMD) and malocclusion in 10-12 year old children and to determine if a relationship exists between symptoms and signs of TMD and malocclusion. The subjects were composed of 465 school children (233 boys and 232 girls). Each subject was evaluated with simplified questionnaire and clinical examination to measure symptoms and signs of TMD and malocclusion. The results showed an elevated prevalence of headache (34.6%), which were more frequent in girls than boys. The most common cardinal sign of TMD was clicking (32.9%), which increased with age. TMJ lateral tenderness was present in 18.1% of the subjects and had a tendency to increase with age. Masseter muscle tenderness was found to be sensitive in 15.1%of the subjects and had a tendency to increase with age. Restriction of mandibular mobilitywas present in 30.3% of the subjects and had a tendency to increase with age. There was no significant difference in the prevalence of TMD signs between sex. The occlusal status showed Class I malocclusion in 73.3%, Class III in 12.9%,Class II division 1 in 11%, Class II division 2 in 2.8%. There was no significant difference in malocclusion traits between sex. There was statistically significant relationship between TMD signs and symptoms and class II division 1 and Class III malocclusion(p<0.05). The results indicate that the prevalence of TMD symptoms and signs in children is high, and the evaluation of TMD in children seems to be important.