• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.2
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• pp.345-350
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• 2008

In children with Class III malocclusion, it is important to identify whether the etiology is functional, dental, skeletal. FR-III developed by Rolf Frankel in 1970, has been used during deciduous, mixed, and early permanent dentition to correct class III malocclusion characterized by maxillary skeletal retrusion. According Frankel, the vestibular shields and upper labial pads act to counteract the forces of the surrounding musculature that restrict forward maxillary development and cause a retrusion in maxillary tooth position. This can achieve favorable developments with the basal bone, teeth and alveolar bone. We report FR-III that can be applicated in cases of early mixed dentition with mild maxillary deficiency and deepbite before the eruption of permanent maxillary incisor.

• The korean journal of orthodontics
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• v.50 no.5
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• pp.346-355
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• 2020

The treatment of skeletal Class III malocclusion in adolescents is challenging. Maxillary protraction, particularly that using bone anchorage, has been proven to be an effective method for the stimulation of maxillary growth. However, the conventional procedure, which involves the surgical implantation of mini-plates, is traumatic and associated with a high risk. Three-dimensional (3D) digital technology offers the possibility of individualized treatment. Customized mini-plates can be designed according to the shape of the maxillary surface and the positions of the roots on cone-beam computed tomography scans; this reduces both the surgical risk and patient trauma. Here we report a case involving a 12-year-old adolescent girl with skeletal Class III malocclusion and midface deficiency that was treated in two phases. In phase 1, rapid maxillary expansion and protraction were performed using 3D-printed mini-plates for anchorage. The mini-plates exhibited better adaptation to the bone contour, and titanium screw implantation was safer because of the customized design. The orthopedic force applied to each mini-plate was approximately 400-500 g, and the plates remained stable during the maxillary protraction process, which exhibited efficacious orthopedic effects and significantly improved the facial profile and esthetics. In phase 2, fixed appliances were used for alignment and leveling of the maxillary and mandibular dentitions. The complete two-phase treatment lasted for 24 months. After 48 months of retention, the treatment outcomes remained stable.

• The korean journal of orthodontics
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• v.36 no.5
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• pp.388-396
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• 2006

Treatment of skeletal Class III malocclusion with mini-implant anchorage is discussed in relation to vertical control of the maxillary posterior dentoalveolar region and horizontal control of mandibular anterior teeth. A midpalatal mini-implant provided anchorage for intruding the maxillary posterior teeth. Mandibular mini-Implant implants were used to bring about labioversion of mandibular anterior teeth. After mandibular setback surgery, improvement of the facial profile was obtained both horizontally and vertically, Total treatment time was 11 months. Stable occlusion was maintained after 18 months of retention, The effectiveness and efficacy of mini-implants for the treatment of skeletal Class III malocclusion are also discussed.

• The korean journal of orthodontics
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• v.53 no.3
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• pp.175-184
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• 2023

Objective: To evaluate and compare a series of volume changes in the nasal cavity (NC), nasopharynx, oropharynx, and maxillary sinuses (MS) in growing Class III patients after either rapid palatal expansion (RPE) or alternate rapid maxillary expansion and constriction (Alt-RAMEC) followed by facemask (FM) therapy, by using cone-beam computed tomography (CBCT). Methods: Forty growing Class III patients were retrospectively selected and divided into two matched groups: RPE/FM (14 females, 6 males; mean age, 9.66 ± 1.23 years) and Alt-RAMEC/FM groups (14 females, 6 males; mean age, 10.28 ± 1.45 years). The anteroposterior and vertical displacements of Point A, the volumes of the NC, nasopharyngeal, oropharyngeal, and MS were measured at different time points: pretreatment (T1), postexpansion (T2), and postprotraction (T3). Results: Both groups demonstrated significant maxilla advancement (by 1.3 mm) during expansion, with a statistically significant intergroup difference during protraction (RPE/FM, 1.1 mm; Alt-RAMEC/FM, 2.4 mm; p < 0.05) and throughout the treatment (RPE/FM, 2.4 mm; Alt-RAMEC/FM, 3.7 mm; p < 0.05). NC and nasopharyngeal airway volumes increased significantly in both groups after expansion, protraction, and treatment. The oropharyngeal and MS volumes increased in both groups after protraction and post-treatment. However, no volumetric differences were observed between the two groups. Conclusions: There was no significant difference in airway volume changes, including NC, nasopharyngeal, oropharyngeal airway, and MS, between RPE/FM and Alt-RAMEC/FM groups at different time points. Although there was significantly more forward movement after protraction in the Alt-RAMEC/FM group, the difference was deemed too small to be clinically relevant.

• The korean journal of orthodontics
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• v.52 no.2
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• pp.85-101
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• 2022

Objective: To classify facial asymmetry (FA) phenotypes in adult patients with skeletal Class III (C-III) malocclusion. Methods: A total of 120 C-III patients who underwent orthognathic surgery (OGS) and whose three-dimensional computed tomography images were taken one month prior to OGS were evaluated. Thirty hard tissue landmarks were identified. After measurement of 22 variables, including cant (°, mm), shift (mm), and yaw (°) of the maxilla, maxillary dentition (Max-dent), mandibular dentition, mandible, and mandibular border (Man-border) and differences in the frontal ramus angle (FRA, °) and ramus height (RH, mm), K-means cluster analysis was conducted using three variables (cant in the Max-dent [mm] and shift [mm] and yaw [°] in the Manborder). Statistical analyses were conducted to characterize the differences in the FA variables among the clusters. Results: The FA phenotypes were classified into five types: 1) non-asymmetry type (35.8%); 2) maxillary-cant type (14.2%; severe cant of the Max-dent, mild shift of the Man-border); 3) mandibular-shift and yaw type (16.7%; moderate shift and yaw of the Man-border, mild RH-difference); 4) complex type (9.2%; severe cant of the Max-dent, moderate cant, severe shift, and severe yaw of the Man-border, moderate differences in FRA and RH); and 5) maxillary reverse-cant type (24.2%; reverse-cant of the Max-dent). Strategic decompensation by pre-surgical orthodontic treatment and considerations for OGS planning were proposed according to the FA phenotypes. Conclusions: This FA phenotype classification may be an effective tool for differential diagnosis and surgical planning for Class III patients with FA.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.3
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• pp.412-420
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• 2001

In the growing children with normal occlusion and class III malocclusion who need the early treatment to be helped to diagnose and to set up treatment plan by calculating the mean values of the lateral cephalometric measurements, cephalometric measurements by McNamara alalysis were achieved and compared on both the 84 elementary school children with normal occlusion and 83 class III malocclusion children at the age of 7 to 9 in Kwangju city and the results were as follows: 1. On the boys group, between normal occlusion and class III malocclusion, Effective maxillary length, Maxillomandibular differential, Facial axis, Nasion perpendicualr to pogonion, Point A perp to Mx 1, and A-Pog line to Mn 1 showed significant differences(p<0.05). 2. On the girls group, between normal occlusion and class III malocclusion significant differences were shown in Effective Maxillary length, Maxillomandibular differential, Mandibular plan angle, Nasion perpendicualr to Point A, Point A perp to Mx 1, A-Pog line to Mn 1(p<0.01). 3. There were no significant differences between normal occlusion and class III malocclusion of boys group but significant differences between them of girls group in Effective mandibular length(P<0.01). On the boys and girls group, Effective maxilla length of class III malocclusion was shorter than that of normal occlusion. 4. There were no significant differences between normal occlusion and class III malocclusion both in boys and girls at Anterior lower facial height. 5. There were significant differences between boys and girls both in class III malocclusion and normal occlusion at Anterior lower facial height and Mandibular plane angle(p<0.01).

• Imaging Science in Dentistry
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• v.52 no.1
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• pp.75-82
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• 2022

Purpose: This cross-sectional study evaluated and categorized the tomographic sagittal root position (SRP) of the maxillary anterior teeth in a Brazilian population. Materials and Methods: Cone-beam computed tomographic scans of 420 maxillary anterior teeth of 70 patients (35 men and 35 women, mean age 25.2±5.9 years) were evaluated. The SRP was classified as class I, II, III, or IV. In class I, the root is positioned against the buccal cortical plate; in class II, the root is centered in the middle of the alveolar housing; in class III, the root is positioned against the palatal cortical plate; and in class IV, at least two-thirds of the root engage both the buccal and palatal cortical plates. Results: In total, 274 teeth (65.2%) were class I, 39 (9.3%) were class II, 3 (0.7%) were class III, and 104 (24.8%) were class IV. The frequency distribution over the teeth groups was different from the overall analysis. Important differences were found in the frequencies of classes I, II, and IV compared to other populations. Sex was not associated with the SRP classes (P=0.307). Age distribution was significantly different over the classes (P=0.004). Conclusion: The findings of this study on the distribution of SRP classes among the Brazilian population compared to other populations demonstrate that the SRP should be analyzed on a case-by-case basis for an accurate treatment plan in the maxillary anterior area.

• The korean journal of orthodontics
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• v.21 no.3
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• pp.685-699
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• 1991

The purpose of this report is to review vertical dysplasia such as openbite or deep bite in skeletal Class III malocclusion and their treatment modality and to present two cases treated with MEAW. The results obtained were as follows A. Open bite case 1. The treatment time was 3 year 8 months. 2. Upper and lower incisors showed extrusion and especially lower anterior alveolar process showed remodelling. 3. The mesially inclined upper and lower molars were uprighted and especially lower first molars showed extrusion that means remodelling of alveolar bone. 4. Normal overbite and overjet were established. 5. Mandible showed slight clockwise rotation. 6. Maxilla showed slight downward bending of ANS part. 7. Upper lip showed downward drop and lower lip showed retraction and touch between upper and lower lip was established. 8. Tongue posture of post-treatment was more raised than pretreatment. B. Deep bite case 1. The treatment time was 1 year 8 months. 2. Upper incisors showed intrusion and labioversion and lower incisors showed slight intrusion and linguoversion. 3. The lower molars showed distal uprighting and intrusion and upper molars showed mesial movement and extrusion. 4. Normal overbite and overjet were established. 5. Maxilla did not show downward movement. 6. Mandible showed slight clockwise rotation. 7. Lower lip showed retraction and downward drop and upper lip showed downward drop.

• The korean journal of orthodontics
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• v.34 no.4 s.105
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• pp.313-324
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• 2004

The Purpose of this study was to investigate the predictors of relapse in orthodontic treatment of skeletal Class III malocclusion in growing patients. A total of 55 patients were studied and all subjects were divided into two groups according to their stability in the post-treatment stage. Of the sample, 33 patients were included in the stable group and the remaining 22 were assigned to the relapse group. Cephalometric data of the pre-treatment stage was taken and compared between the stable and relapse group. The following results were obtained through t-test: 1. This study presented statistical evidence to show that the major skeletal determinant of prognosis in Class III orthodontic treatment was not anteroposterior discrepancy .but vertical discrepancy, especially within the AB-maxillo mandibular triangle. Vertical angular measurements that showed statistically significant differences were AB-MP and ODI(P<0.01) and the vortical ratio measurements were MP-P/AL and PP-P/AL(P<0.05). 2. Relapse tendency increased with the steep occlusal Plane, especially the steep lower occlusal plane. As to occlusal plane, there were statistically significant differences in OP(L)-PP, OP-PP, AB-OP(L) and Wits appraisal(P<0.05). This study claimed that anteroposterior discrepancy was not necessarily the proper criteria to predict relapse. Vertical discrepancy had a significant effect on post-treatment stability.

• 대한치과교정학회:학술대회논문집
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• 2005.11a
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• pp.69.1-69.1
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• 2005