• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.2
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• pp.323-328
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• 2001

Anterior open bite is one in which the teeth in the anterior portion of the maxilla and mandible are vertically apart and lack the overlapping necessary for the incisive function when the mandible is in closed position. Anterior open bite is a result of the interaction of many different etiologic factors including thumb and finger sucking, lip and tongue habits, airway obstruction, skeletal growth abnormalities and its tendency may appear with any type of skeletal patterns, such as Class I, II or III malocclusion types. Though the treatment methods for anterior open bite are various, the conventional FR-4, designed by Rolf Fr$\"{a}$nkel, is known to be effective in treating open bite cases with Class I or II skeletal patterns. It is due to that an incidence of skeletal Class II is high in the Occidentals, and open bite is accompanied by these malocclusion type in many cases. However, an incidence of skeletal Class III is high in the Orientals, and open bite is sometimes accompanied by skeletal Class III in many cases. Although the use of the conventional FR-4 was effective in the treatment of open bite, skeletal Class III would be worsened. So, a modified FR-4(placing the labial bow in the lower, the labial pads in the upper) was designed for the treatment of patients showing skeletal Class III and open bite.

• The korean journal of orthodontics
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• v.28 no.2 s.67
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• pp.189-201
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• 1998

The purpose of this study was to evaluate the characteristics of craniofacial skeleton on orthognathic surgical cases with skeletal Class III malocclusion. For this study, 74 students at the dental college of Chosun University volunteered as a normal occlusion group. They had well-balanced faces and good occlusions with acceptable Class I molar relationship. They had not received orthodontic treatment and had no signs or symptoms of temporomandibular joint dysfunction. 45 malocclusion patients enrolled for orthognathic surgical treatment with skeletal Class III malocclusion at the Department of Orthodontics, College of Dentistry, Chosun University. On the basis of this study. the results of this study were as follows: 1. Skeletal Class III malocclusion was largely due to the overgrowth of mandible in man and the undergrowth of maxilla in woman. 2. The mandible was antero-inferiorly overgrown by large MP-HP angle and large genial angle in orthognathic surgical cases with skeletal Class III malocclusion. And also, upper incisors were severely labioversioned, but on the other hand lower incisors were linguoversioned. 3. In female, lower-third facial height was characteristically shortened in comparison with middle-third facial height and also, lower facial throat angle was small in male.

• The korean journal of orthodontics
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• v.32 no.1 s.90
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• pp.33-42
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• 2002

This study was performed to compare the pattern of dentoalveolar characteristics in different vertical and anteroposterior skeletal types in skeletal Class III malocclusion. The samples selected for this study were consisted of 60 subjects(29 males and 31 females, mean age; 19.7 years) in Class III group, 43 subjects(14males and 29 females, mean age : 20.5 years) in normal group. The findings of this study were as follows : 1. The IMPA of the Class III group was smaller than that of the Class I group(p<0.01). 2. In the Class III groups, SNB and NtoPog had negative correlation with IMPA(p<0.01). The SNB and NtoPog had correlations with SNU1, FHU1 and PalU1(p<0.01) in the male samples, and in the female samples, the SNB and NtoPog had correlations with SNU1(p<0.01). 3. In the Class III male samples, SNMP, FMA, PalMP had negative correlation with IMPA(p<0.01). SNMP, FMA, PalMP had not significant correlation with SNU1, FHU1, PalU1. In the Class III female samples, FMA, PalMP had negative correlation with IMPA(p<0.01). 4. In the high angle group of Class III samples, SNU1, IMPA is smaller than that of low angle group of Class III samples(p<0.05).

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.2
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• pp.147-153
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• 2017

This study assessed the association between ectopic eruption of the maxillary first permanent molar and skeletal malocclusion in 5- to 10-year-old children. As subjects, 786 children who attended the Wonkwang University Dental Hospital for orthodontic diagnosis were included. Children with unerupted first permanent molars or fully erupted second permanent molars were excluded. The study group demonstrated ectopic eruption of the maxillary first permanent molar, while the control group did not. Cephalometric radiographs taken between January 2003 and August 2015 were analyzed. Skeletal class III malocclusion was detected in 57.0% of the study group, which differed significantly from that in the control group (p<0.05). The SNA, ANB angles, and A to N-perpendicular distance were significantly smaller, whereas the A-B plane angle and APDI were significantly greater in the study group than in the control group (p<0.05). The SNB and mandibular plane angles were not significantly different between the groups. Thus, maxillary undergrowth is a risk factor for ectopic eruption of the maxillary first permanent molar.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.4
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• pp.479-484
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• 2000

The conventional treatment of skeletal class III malocclusion has been focused on the application of orthopedic forrce primarily to the mandible. Thus moderate Class III malocclusions can be corrected by the anterior displacement of the maxilla and maxillary dentition, possibly by restricting the growth of the mandible or by changing its direction. The patients having skeletal Class III malocclusion were treated with removable appliance & fixed appliance for detailed tooth movement and the following results were observed: 1. The anterior crossbite was corrected. 2. The forward and downward growth of the maxillary complex was obtained. 3. The lingual tipping of the mandiblar incisors was performed and the mandible was rotated in the clockwise direction.

• The korean journal of orthodontics
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• v.27 no.6 s.65
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• pp.997-1004
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• 1997

The clinical cases presented here involve skeletal Class III malocclusion cases treated with maxillary protraction in a relatively short period of time with good results. When used on young patients, satisfactory results were obtained in a short period of time, but even for those with less growth potential remaining, skeletal enhancement was still evident. However, data on the criteria of diagnosis or relapse following maxillary protraction is limited despite the number of studies on the subject. The present study could not include the observations on retention and relapse, and further studies in the future nay include such observations.

• The korean journal of orthodontics
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• v.38 no.1
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• pp.60-67
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• 2008

Treatment of adult patients with Class III malocclusion frequently requires a combined orthodontic and surgical approach. However, if for various reasons, nonsurgical orthodontic treatment is chosen, a stable outcome requires careful consideration of the patient's biologic limitation. This case presents the orthodontic treatment of an adult with a Class III malocclusion, which was treated nonsurgically using indirect skeletal anchorage.

• The korean journal of orthodontics
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• v.27 no.5 s.64
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• pp.801-813
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• 1997

A comparative study was made on the chewing movements of normal occlusion and skeletal class m malocclusion. Thirty normal occlusion subjects and twenty skeletal class III malocclusion patients were given chewing gums for the study : using BioPAK system, the chewing movement on the frontal plane was recorded and analyzed. With a typical chewing path chosen representing each subject, chewing width, opening distance, opening and closing angles, maximum opening and closing velocities were observed. Seven characteristic patterns were classified based on the types of chewing paths. The followings are the results : 1. Compared with the normal occlusion group, the skeletal class III malocclusion group showed more varied and vertical chewing patterns. 2. In comparision of chewing widths, skeletal class m malocclusion group showed narrower path than the normal occlusion group(p<0.01). 3. In opening distance, skeletal class III malocclusion group appeared shorter than the normal occlusion group without statistical significance(p>0.05). 4. In opening and closing angles, skeletal class III malocclusion group showed more acute angles than the normal occlusion group(p<0.01). 5. In maximum opening and closing velocities, skeletal class III malocclusion group was slower than the normal occlusion group but with no statistical significance(P>0.05). 6. In the classification of chewing movement pattern, the normal occlusion group had Type II as the highest rate at 73.4% ; in skeletal class III malocclusion group, the highest rate was Type III at 35.0%, followed by Type II at 30.0% 7. In the classification of chewing movement pattern, Type IV(chopping type)of skeletal class III malocclusion group showed a higher rate with 25.0% over 3.3% of normal occlusion group.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.4
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• pp.694-699
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• 2001

The prognosis for class III patients in growing child can be made in mixed dentition and the severity of the symptom is often amenable to early intervention. Class III malocclusion can be classified as functional class lit and skeletal origin. Skeletal Class III malocclusion is usually characterized by overdeveloped mandible, underdeveloped maxilla, but the cause of pseudo class III is most dentoalveolar or functional shift of mandible. The primary goal of early intervention of malocclusion is to supply an environment that is conducive to the development of favorable occlusal relationships and avoiding of worsening of the problems. Inverted labial bow appliance is introduced as an appliance to combine the advantage of active plate and activator. It is undemanding with this appliance to initiate not only dentoalveolar expansion of upper dentition but also to orient the functional retrusion of mandible. With simple design the compliance for patients such as mouth breathing problem can be improved. For successful use of this appliance it is utmost important to make accurate and early diagnosis between pseudo- and skeletal class III malocclusion. This article will demonstrate the use of an Inverted labial bow appliance for early treatment of a functional Class III malocclusion. After 4 month treatment, anterior crossbite was treated and the results were achieved mainly dentoalveolar change of upper and lower anterior teeth.

• The korean journal of orthodontics
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• v.37 no.4
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• pp.260-271
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• 2007

The purpose of this study was to evaluate the relationships between the occlusal plane angle and craniofacial skeletal pattern in relation to anterior overbite. Methods: Lateral cephalograms of 90 adults with skeletal class III malocclusions were traced and measured to analyze skeletal factors and occlusal plane angles. In terms of anterior overbite, all patients were classified into 3 subgroups of positive overbite, edgebite, and negative overbite groups. All measurements were evaluated statistically by ANOVA and Duncan's Post Hoc, and correlation coefficients were evaluated among measurements. Results: In this study, some skeletal measurements (saddle angle, articular angle, Y axis, AFH, SN-FH, SN-Mn, FH-Mn) showed a significant difference among the 3 groups in relation to overbite changes. Correlation coefficient showed that PFH/AFH, SN-Mn, Mx-Mn, and FH-Mn showed a significant difference with FH-Occ, Mx-Occ, and Mn-Occ. Regression analysis showed that Mx-Mn had a determination coefficient of 0.714, 0.560, and 0.677 in relation to FH-Occ, Mx-Occ, and Mn-Occ, respectively. Conclusion: This study suggests that consideration of the occlusal plane in relation to the maxillomandibular vertical skeletal state enable the establishment of a more predictable orthognathic surgery result.