• Journal of Dental Rehabilitation and Applied Science
• /
• v.26 no.3
• /
• pp.349-357
• /
• 2010

Physical factors and intra- and extra-oral factors of a patient have to be considered in order to decide a treatment plan for the skeletal class III malocclusion patient. Most of cases, the pre-prosthodontic treatment requires the orthodontic approaches and maxillofacial surgery. However, in some cases, patients' economic or medical condition makes impracticable situation for the orthodontic or surgical intervention. For those cases, the compromised prosthetic treatment which provides more stable and persistent occlusal stabilization is recommended. In this case report, a woman patient has a skeletal class III maxillomandibular relationship and misses multiple teeth. The prosthetic treatment without orthodontic and surgical intervention is performed due to her physical problem. The functional and esthetic results are achieved by the fixed prosthesis.

• The korean journal of orthodontics
• /
• v.37 no.3 s.122
• /
• pp.231-240
• /
• 2007

Objective: The purpose of this study was to investigate the maxillary protraction effects of the Tandem Traction Bow Appliance (TTBA), a new appliance devised several years ago for the treatment of growing skeletal Class III patients. Methods: Participants were 88 Korean children (42 boys, 46 girls) with skeletal Class III malocclusion treated with TTBA at the orthodontic clinic of Ewha Womans University Mokdong Hospital. Mean age at the start of treatment was 7.5 years${\pm}$1.5 years. Mean treatment periods were $13{\pm}3$ months. Pretreatment and posttreatment lateral cephalograms were traced and superimposed by the same investigator and analyzed by modified McNamara analysis and pitchfork analysis. Changes were evaluated with paired t-tests at a significance level of p<0.05. Results: The maxilla and maxillary dentition moved forward. The mandible moved backward, although not significantly; and the mandibular dentition moved forward. The net dental changes combined with the apical base change resulted in a favorable total molar relationship correction. Net dental movement was 26% and the apical base change 74% of the total molar relationship correction. Conclusion: These results suggest that TTBA has a maxillary protraction effect that can be useful in the treatment of growing skeletal Class III malocclusion with maxillary deficiency.

• The korean journal of orthodontics
• /
• v.39 no.2
• /
• pp.72-82
• /
• 2009

Objective: The purpose of this study was to investigate the structural changes of the hyoid bone and upper airway after orthognathic surgery for skeletal class III anterior open bite patients, and make comparisons with normal occlusion. Methods: Pre- and post-operative computed tomography (CT) examinations were performed on 12 skeletal class III anterior open bite patients who were treated with mandibular setback osteotomy. Using the V-works $4.0^{TM}$ program, 3-dimensional images of the total skull, mandible, hyoid bone, and upper airway were evaluated. Results: In the Class III open bite group, the hyoid bone were all positioned anteriorly, compared to the Normal group (p < 0.05). The angle between the hyoid plane and mandibular plane in the Class III openbite group before surgery was greater than in the Normal group (p < 0.05), and the difference increased after surgery (p < 0.01). In the Class III openbite group, the volume of the upper airway decreased after surgery (p < 0.001) and the volume of the upper airway was smaller than the Normal group before and after surgery (p < 0.001). Conclusions: The narrow upper airway space in skeletal Class III openbite patients decreased after mandibular setback osteotomy. This may affect the post-surgical stability.

• The korean journal of orthodontics
• /
• v.28 no.5 s.70
• /
• pp.751-761
• /
• 1998

The purpose of this study was to find the characteristics of lateral crphalogram of skeletal class III malocclusion patients to whom orthognathic surgery was essential. For this study 37 patients with skeletal class III and going to treat or be treated orthognathic surgery(age 7-17) were selected to experimental group and 56 people with normal occlusion (age 8-13) were selected to normal group and the two groups were evaluated and statistically analyzed and the results were as follows 1. In comparison of experimental group and normal group in prepubertal group, there were significant differences in ANS-U1/Me-L1, Mx. Length/Mn. Length, S-N/Go-Me, Wits, ANB, SN-Pog, IMPA, Facial Convexity, APDI (p<0.05) 2. In comparison of experimental group and normal group in pubertal group, there were significant differences in ANS-U1/Me-L1, S-Go/N-Me, Mx.Length/Mn.Length, S-N/Go-Me, Wits, Saddle Angle, SNB, ANB, SN-Pog, IMPA, Interincisal Angle, Facial Convexity, APDI (p<0.05) 3. Among items showing characteristics of skeletal class III malocclusion, there were no significant differences between prepubertal group and pubertal group in other items except Mx. Length/Mn. Length,APDI (p<0.05) 4. The significant correlationship was the highest between Saddle Angle and SNB, SN-Pog and SNB, ANB and Facial Convexity in experimental group

• The korean journal of orthodontics
• /
• v.38 no.2
• /
• pp.83-94
• /
• 2008

Purpose: The first objective of this study was to compare the upper midface morpholgy, focusing on the soft tissues, between skeletal Class III maloccusion patients with midfacial depression and the norm. The second objective was to estimate and analyze the change in the upper midface soft tissues following surgical correction with maxillary advancement by Lefort I osteotomy and mandibular setback by bilateral sagittal split osteotomy (BSSRO). Methods: The samples consisted of 34 adult patients (15 males and 12 females) with an average age of 21 years, who had severe anteroposterior discrepancy with midfacial depression. These patients had received presurgical orthodontic treatment and surgical treatment which consisted of simultaneous Lefort I osteotomy and BSSRO. Results: The correlation coefficient between changes in maxillary advancement and changes in Or' (soft tissue orbitale) was 0.599 (p < 0.05). Change in maxillary plane angle and vertical change of the maxilla were not correlated with the change in Or' (p < 0.05). The ratio of soft tissue change in Or' to maxillary advancement was 43.57 %, and 81.54 % in Sn. Regression equations between maxillary movement and Or' were devised. The $r^2$ value was 0.476. Conclusions: The majority of measurements in the upper midface in skeletal Class III maloccusions when compared to the norm, showed significant differences. In Class III malocclusion with midfacial depression, maxillary advancement produces soft tissue change in the upper midface.

• The korean journal of orthodontics
• /
• v.32 no.2 s.91
• /
• pp.117-127
• /
• 2002

The purpose of this study was to compare the arch width of the hyperdivergent group with that of the neutral group in Class III malocclusion based on the vertical patterns and to compare the arch width of Class III neutral group With that of normal occlusion group based on sagittal patterns. The subjects consisted of 118 pairs of studty casts, divided into three groups , 37 Class III hyperdivergent group(18 males and 19 females, SN-Mn plane angle>39.5$^{\circ}$), 40 Class III neutral group(20 males and 20 females, SN-Mn plane angle : 32 ${\pm}$ 2.5$^{\circ}$) and 41 Class I normal occlusion group(20 males and 21 females). The intercanine, interpremolar, and intermolar width of the maxillary and mandibular study casts were measured, then the ratios of dental width to basal width and mandibular width to maxillary width were obtained. Basal arch width and dental arch width were measured to obtain the pure basal arch relation in transverse plane as ruled out the transverse dental compensation. The results were as follows 1. There were no significant differences in any ratios between Class III hyperdivergent group and Class III neutral group as different vertical pattern. 2. As the ratios of dental arch width to basal arch width between normal occlusion group and Class III neutral group were compared, the maxillary teeth flared buccally to the basal bone, and the mandibular teeth tilted lingually to the basal bone in Class III neutral group. 3. The ratios of mandibular arch width to maxillary arch width in basal arch level were significantly different in all regions. Maxillary basal arch width of Class III neutral group was narrower than that of normal occlusion group. 4. The ratios of mandibular arch width to maxillary arch width in teeth level were not significantly different between normal occlusion group and Class III neutral group. In spite of discrepancies of maxillary and mandibular basal arch width, the dental arch width of Class III malocclusion group compensated very well. At the presurgical orthodontic treatment in clinic, it would not be desirable to decompensate for compensated dental arch width too much, for obtaining an appropriate arch compatibility and good results for orthognathic surgery.

• 대한치과교정학회:학술대회논문집
• /
• 1998.10a
• /
• pp.82.3-82.3
• /
• 1998

• 대한치과교정학회:학술대회논문집
• /
• 2000.11a
• /
• pp.51.3-52
• /
• 2000

• 대한치과교정학회:학술대회논문집
• /
• 2003.10a
• /
• pp.104.1-104.1
• /
• 2003

• The korean journal of orthodontics
• /
• v.40 no.5
• /
• pp.349-357
• /
• 2010

Objective: The purpose of this study was to evaluate the dentoskeletal and soft tissue profile changes after extraction of two lower first or second premolars in "borderline" adult skeletal Class III cases. Methods: Twenty-eight patients with "borderline" skeletal Class III malocclusion were studied. All of them were treated by extraction of two lower first or second premolars. Lateral cephalometric radiographs taken at the start and end of treatment were analysed. Twenty-five cephalometric variables were calculated and paired $t$-tests were performed. Results: After treatment, no significant changes were noted in the skeletal parameters ($p{\geq}0.05$). Regarding the dental parameters, the L1-MP angle decreased by $8.1^{\circ}$, the U1-L1 angle increased by $7.7^{\circ}$ ($p$ < 0.01), the overjet distance increased by 5.7 mm ($p$ < 0.01), the L1-NB angle decreased by $7.3^{\circ}$ and the L1-NB distance decreased by 4.8 mm ($p$ < 0.01). The soft tissue parameters of Li-E, Li-H and Li-RL2 distance decreased by 3.2 mm, 3.4 mm and 4.1 mm respectively ($p$ < 0.01). Conclusions: Orthodontic camouflage treatment by extraction of two lower first or second premolars provides a viable treatment alternative for "borderline" skeletal Class III cases to achieve a good occlusal relationship.