• 대한치과교정학회지
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• 제46권3호
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• pp.137-145
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• 2016

Objective: The purpose of this study was to investigate the characteristics of orthodontic patients at Yonsei Dental Hospital from 2008 to 2012. Methods: We evaluated Angle's classification from molar relationships, classification of skeletal malocclusion from the A point-nasion-B point angle, facial asymmetry, and temporomandibular joint disorders (TMDs) from the records of 7,476 patients who received an orthodontic diagnosis. The orthognathic surgery rate, extraction rate, and extraction sites were determined from the records of 4,861 treated patients. Results: The patient number increased until 2010 and gradually decreased thereafter. Most patients were aged 19-39 years, with a gradual increase in patients aged ${\geq}40years$. Angle's Class I, Class II divisions 1 and 2, and Class III malocclusions were observed in 27.7%, 25.6%, 10.6%, and 36.1% patients, respectively, with a gradual decrease in the frequency of Class I malocclusion. The proportion of patients with skeletal Class I, Class II, and Class III malocclusions was 34.3%, 34.3%, and 31.4%, respectively, while the prevalence of facial asymmetry and TMDs was 11.0% and 24.9%, respectively. The orthognathic surgery rate was 18.5%, with 70% surgical patients exhibiting skeletal Class III malocclusion. The overall extraction rate among nonsurgical patients was 35.4%, and the maxillary and mandibular first premolars were the most commonly extracted teeth. Conclusions: The most noticeable changes over time included a decrease in the patient number after 2010, an increase in the average patient age, and a decrease in the frequency of Angle's Class I malocclusion. Our results suggest that periodic characterization is necessary to meet the changing demands of orthodontic patients.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권6호
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• pp.506-513
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• 2006

The purpose of this study was to examine the familial tendency of the patients with mandibular prognathism in three generations and to define the relationship between the familial tendency and the skeletal class III morphology. The probands of this study were 103 orthognathic surgery patients with skeletal Class III malocclusions who had undergone (48 men, 55 women) mandibular set-back surgery. A questionnaire was given to patients who sought surgical treatment for excessive mandibular length, and all answers were confirmed in interviews. Lateral cephalograms were analyzed in cranial base parameters, mandibular positional parameters and mandibular skeletal parameters. In the examined families, 58.3% had at least one member other than the proband who had mandibular prognathism. The affected ratio of total relatives was 4.5%, and the value was higher in first-degree (13.4%) than second-degree (5.9%) and third-degree relatives (1.7%). The affected ratio was 51.9% in the offsprings who had at least one affected father or mother. The comparison of the groups according to the familial tendency showed no significant craniofacial skeletal measurments. In conclusion, skeletal class III malocclusion showed high familial tendency, suggesting a significant genetic influence in the etiology. However, the patient's familial tendency did not show the special craniofacial patterns compare to the subjects without familial tendency.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권1호
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• pp.27-34
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• 2006

After orthognathic surgery in skeletal class III patients, the hyoid bone position and the upper airway dimension could be changed due to mandibular setback. There has been many studies about airway dimension of the patients with skeletal class II malocclusion or obstructive sleep apnea. but not with skeletal class III. The purpose of this study was to examine the change of position of the hyoid bone and the consequent change of airway space as the result of retrusion of mandible after orthognathic surgery in skeletal Cl III malocclusion patients. It is also to apply this results in predicting, diagnosing and treating the subsequent obstructive sleep apnea. Forty patients who were diagnosed as skeletal Cl III maloccusion, received orthoganthic surgery of both jaws including mandibular setback, and were followed up post-operatively for more than 6 months were selected. There were 10 male patients 30 female patients. The preoperative and postoperative lateral cephalograms were traced and the distances and angles were measured. The nasopharyngeal space increased postoperatively while the oropharyngeal space decreased. Except for the change of oroparyngeal space, the changes in male patients were greater than female patients. The hyoid bone moved in the posterior-inferior direction, and the change was greater in males than in females. If the postoperative mandibular setback is great, then a significant decrease of airway space and posterior and inferior movement of the hyoid bone were observed. This can result in symptoms related to obstructive sleep apnea. This result should be considered in the diagnosis and treatment planning of orthognathic surgery patients.

• 대한치과교정학회지
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• 제27권5호
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• pp.801-813
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• 1997

정상교합자와 골격성 III급 부정교합자의 저작운동형태를 비교연구하기위해서 30명의 정상교합자와 20명의 골격성 III급 부정교합자를 대상으로 츄잉검을 사용하고 BioPAK system을 이용하여 전두면상에서 저작운동을 기록, 분석하였다. 각 개체마다 대표하는 저작경로를 정하여 저작폭경, 개구거리, 개구각, 페구각, 최대개구속도, 최대폐구속도를 알아보았다. 또 저작경로의 형태에 따라 특징적인 7가지 패턴으로 분류하여 다음의 결과를 얻었다. 1. 정상교합자군에 비해 골격성 III급 부정교합자군에서는 좀 더 다양하고 수직적인 저작양상을 나타내었다. 2. 저작폭경의 비교에서는 골격성 III급 부정교합자군이 정상교합자군에 비해 더 좁게 나타났다(p<0.01) 3. 개구거리에서는 골격성 III급 부정교합자군이 정상교합자군에 비해 더 작게 나타났으나 통계학적으로 유의성은 없었다(p>0.05). 4. 개구각과 폐구각에서는 골격성 III급 부정교합자군에서 정상교합자군보다 더욱 예각으로 나타났다(p<0.01). 5. 최대개구속도, 최대폐구속도에서는 정상교합자군에 비해 골격성 III급 부정교합자군에서 느리게 나타났으나 통계학적으로 유의성은 없었다(p>0.05). 6. 저작운동형태에 따른 분류에서 정상교합자군에서는 Type II가 73.4%로 가장 많은 비율을 차지하였으나, 골격성 III 급 부정교합자군에서는 Type III가 35.0%, Type II가 30.0%로 많은 비율을 차지하였다. 7. 저작운동형 태에 따른 분류에서 골격성 III급 부정교합자군에서는 Type IV(chopping type)가 25.0%로 정상교합자군 3.3%에 비해 많은 비율을 차지하였다.

• 대한치과교정학회지
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• 제47권3호
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• pp.167-175
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• 2017

Objective: To evaluate the differences in maxillomandibular transverse measurements at either the crown or the estimated center of resistance (CR), and to compare values between normal occlusion and Class III malocclusion groups. Methods: Dental casts and computed tomography (CT) data from 30 individuals with normal occlusion and 30 with skeletal Class III malocclusions were evaluated. Using the casts, dental arch widths (DAWs) were measured from the cusp tips, and basal arch widths (BAWs-cast) were measured as the distance between the points at the mucogingival junction adjacent to the respective cusp tips. The BAWs determined from CT (BAWs-CT) images were measured from the estimated CRs of the teeth. Results: None of the DAW measurements or maxillomandibular DAW differences showed statistically significant intergroup differences. In contrast, the maxillary BAWs-CT and BAWs-cast were lesser in the Class III malocclusion group than in the normal occlusion group. The mandibular BAWs-CT were significantly greater in the Class III malocclusion group than in the normal occlusion group. Moreover, the maxillomandibular BAW differences on both CT and cast showed significant intergroup differences in all transverse measurements. Conclusions: The maxillomandibular DAW differences showed no significant intergroup differences. In contrast, the maxillomandibular BAW differences on both CT and cast showed significant intergroup differences in all transverse measurements. The maxillomandibular BAW differences at the estimated CRs, measured using CT or casts, can reveal underlying transverse maxillary basal arch deficiencies in patients with skeletal Class III malocclusions.

• 대한치과교정학회지
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• 제26권3호
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• pp.247-254
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• 1996

골격성 III급 부정교합자의 설골 위치와 기도를 평가하고 이들 사이의 상관관계를 알아보기 위해 부산대학교병원 치과교정과에 내원한 16세 이상의 환자 47명과 치과대학에 재학중인 학생 44명을 대상으로 측모 두부방사선규격사진을 촬영하고 설골의 위치에 대한 전후방적, 수직적 거리 및 각도와 기도의 크기, 하악의 위치에 대해 통계적으로 분석하여 다음과 같은 결론을 얻었다. 1. S-APH, A-APH, N-APH, LAH-PBR, AA-PNS, PNS-ad는 I급 부정교합군과 III급 부정교합군 사이 에 유의한 차이를 보였다. 2. 설골은 III급 부정교합군에서 더 전방에 위치하였으며 경조직 기도 크기는 III급 부정교합군에서 I급 부정 교합군보다 더 작게 나타났다. 3. 다수의 계측치, 특히 설골의 수직적 및 각도 계측치와 기도 크기가 남성과 여성에서 유의한 차이를 보였다. 대개 남성에서 여성보다 수치가 크게 나타났다. 4. 설골의 위치와 기도 크기 사이에 유의한 상관관계는 없었으며 하악의 위치와 기도 크기 사이에도 유의한 상관관계는 없었다. 5. S-APH는 W its appraisal과 역상관관계를 보였으며 A-APH, N-APH는 Wits appraisal과 순상관관계를 보였다. 설골의 수직적 계측치는 하안모 고경과 순상관관계를 나타냈다.

• 대한치과교정학회지
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• 제45권2호
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• pp.95-101
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• 2015

The aim of this case report is to describe the treatment of a patient with skeletal Class III malocclusion with maxillary retrognathia using skeletal anchorage devices and intermaxillary elastics. Miniplates were inserted between the mandibular lateral incisor and canine teeth on both sides in a male patient aged 14 years 5 months. Self-drilling mini-implants (1.6 mm diameter, 10 mm length) were installed between the maxillary second premolar and molar teeth, and Class III elastics were used between the miniplates and miniscrews. On treatment completion, an increase in the projection of the maxilla relative to the cranial base (2.7 mm) and significant improvement of the facial profile were observed. Slight maxillary counterclockwise ($1^{\circ}$) and mandibular clockwise ($3.3^{\circ}$) rotations were also observed. Maxillary protraction with skeletal anchorage and intermaxillary elastics was effective in correcting a case of Skeletal Class III malocclusion without dentoalveolar side effects.

• 대한치과의사협회지
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• 제46권2호통권465호
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• pp.88-99
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• 2008

In growing patients with Class III malocclusion and midfacial deficiency, the treatment protocol calls for orthopedic maxillary protraction and clinicians choose the facemask therapy generally. But facemask is not esthetic or comfortable to patients because it should be worn extraorally. Consequently it is difficult to obtain patients cooperation, and this often influences the treatment effects negatively. MTA (modified tandem appliance), that is a small intraoral appliance, is carried conveniently and esthetic relatively. So it seemed more patient-friendly than a facemask. While the treatment effect of this is similar to that of a facemask. This report presents skeletal Class III malocclusion two cases treated by MTA with good results.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제38권
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• pp.18.1-18.9
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• 2016

Background: The aim of this study was to examine the relationship between improvements in lip asymmetry at rest and while smiling after orthognathic surgery in patients with skeletal class III malocclusion. Methods: This study included 21 patients with skeletal class III malocclusion and facial asymmetry. We used preoperative and postoperative CT data and photographs to measure the vertical distance of the lips when smiling. The photographs were calibrated based on these distances and the CT image. We compared preoperative and postoperative results with the t test and correlations between measurements at rest and when smiling by regression analyses. Results: There were significant correlations between the postoperative changes in canting of the mouth corners at rest, canting of the canines, canting of the first molars, the slope of the line connecting the canines, and the slope of the line connecting first molars. The magnitude of the postoperative lip line improvement while smiling was not significantly correlated with changes in the canting and slopes of the canines, molars, and lip lines at rest. Conclusions: It remains difficult to predict lip line changes while smiling compared with at rest after orthognathic surgery in patients with mandibular prognathism, accompanied by facial asymmetry.

• 한국치위생학회지
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• 제18권4호
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• pp.525-533
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• 2018

Objectives: This retrospective study evaluated the changes in the airway width after the orthognathic surgery associated with the skeletal Class III malocclusion. Methods: The lateral cephalograms of 30 adult patients were taken before and immediately after the operation, and after the orthodontic treatment. The angles and distances of them were measured and compared. Results: Before the surgery, the mean value of mandibular (S-B) setback was 9.66 mm, and moved by 1.56 mm anteriorly after the orthodontic treatment. The ANB increased by 5.42 degrees, since then it decreased by 0.68 degree. The hyoid bone (S-APH) moved by 5.05 mm posteriorly, but then moved by 2.26 mm anteriorly. The soft tissue width of laryngeal pharynx (apw2-ppw2) was narrowed by 1.04 mm, and decreased by additional 0.83 mm after the orthodontic treatment. Conclusions: As the mandible was moved back, the location of hyoid bone and laryngeal pharynx were moved backward.