• 대한소아치과학회지
• /
• 제7권1호
• /
• pp.63-74
• /
• 1980

The purpose of this study is to analyze the width and length changes of the dental arches during the deciduous dentition period. 600 stone models of maxillary and mandibular arches obtained from the children aged 3, 4, or 5 years were under measurement. The results were as follows ; Arch widths and lengths differed with age, sex and arch. 1. * Widths of dental archs increase with age both in males and in females. * Lengths of dental arches decrease with age in females, but remain somewhat stable in males. 2. * The dental arches of males were wider than those of females in both the ant. and the post. section. * The dental arches of males were longer than those of females: ant.arch lengths were almost same, but post. arch lengths were longer in males. 3. * Upper arches were definitely wider and longer than lower arches.

• 대한소아치과학회지
• /
• 제7권1호
• /
• pp.13-16
• /
• 1980

The purpose of this study is to analyze the changes of arch circumferences during the deciduous dentition period. 600 stone models of maxillary and mandibular arches obtained from the children aged 3,4, or 5 years were under measurement. 1. Arch circumferences increase with age both in males and in females. 2. Arch circumferences of males are longer than females at the age of 4 and 5, but no notable differences at the age of 3. 3. Arch circumferences of upper arches are longer than those of lower arches.

• 대한치과교정학회지
• /
• 제48권3호
• /
• pp.153-162
• /
• 2018

Objective: The aim of this trial was to compare the alignment efficiency and intermaxillary arch dimension changes of nickel-titanium (NiTi) or copper-nickel-titanium (CuNiTi) round archwires with increasing diameters applied sequentially to the mandibular arch. Methods: The initial alignment phase of fixed orthodontic treatment with NiTi or CuNiTi round archwires was studied in a randomly allocated sample of 66 patients. The NiTi group comprised 26 women, 10 men, and the CuNiTi ($27^{\circ}C$) group comprised 20 women, 10 men. The eligibility criteria were as follows: anterior mandibular crowding of minimum 6 mm according to Little's Irregularity Index (LII), treatment requiring no extraction of premolars, 12 to 18 years of age, permanent dentition, skeletal and dental Class I malocclusion. The main outcome measure was the alignment of the mandibular anterior dentition; the secondary outcome measure was the change in mandibular dental arch dimensions during 12 weeks. Simple randomization (allocation ratio 1:1) was used in this single-blind study. LII and mandibular arch dimensions were measured on three-dimensional digital dental models at 2-week intervals. Results: No statistically significant difference was observed between NiTi and CuNiTi according to LII (p > 0.05). Intercanine and intermolar arch perimeters increased in the CuNiTi group (p < 0.001). Inter-first premolar width showed a statistically significant interaction in week ${\times}$ diameter ${\times}$ application (p < 0.05). Conclusions: The effects of NiTi and CuNiTi round archwires were similar in terms of their alignment efficiency. However, the intercanine and intermolar arch perimeters, and the inter-first premolar width changes differed between groups.

• 대한치과교정학회지
• /
• 제46권5호
• /
• pp.280-289
• /
• 2016

Objective: The aim of this study was to analyze tooth movement and arch width changes in maxillary dentition following nonextraction treatment with orthodontic mini-implant (OMI) anchorage in Class II division 1 malocclusions. Methods: Seventeen adult patients diagnosed with Angle's Class II division 1 malocclusion were treated by nonextraction with OMIs as anchorage for distalization of whole maxillary dentition. Three-dimensional virtual maxillary models were superimposed with the best-fit method at the pretreatment and post-treatment stages. Linear, angular, and arch width variables were measured using Rapidform 2006 software, and analyzed by the paired t -test. Results: All maxillary teeth showed statistically significant movement posteriorly (p < 0.05). There were no significant changes in the vertical position of the maxillary teeth, except that the second molars were extruded (0.86 mm, p < 0.01). The maxillary first and second molars were rotated distal-in ($4.5^{\circ}$, p < 0.001; $3.0^{\circ}$, p < 0.05, respectively). The intersecond molar width increased slightly (0.1 mm, p > 0.05) and the intercanine, interfirst premolar, intersecond premolar, and interfirst molar widths increased significantly (2.2 mm, p < 0.01; 2.2 mm, p < 0.05; 1.9 mm, p < 0.01; 2.0 mm, p < 0.01; respectively). Conclusions: Nonextraction treatment with OMI anchorage for Class II division 1 malocclusions could retract the whole maxillary dentition to achieve a Class I canine and molar relationship without a change in the vertical position of the teeth; however, the second molars were significantly extruded. Simultaneously, the maxillary arch was shown to be expanded with distal-in rotation of the molars.

• Journal of Korean Dental Science
• /
• 제7권2호
• /
• pp.66-79
• /
• 2014

Purpose: To analyze the amount and pattern of tooth movement and the changes in arch dimension of mandibular dentition after orthodontic treatment using a new three-dimensional (3D)-indirect superimposition method. Materials and Methods: The samples consisted of fifteen adult patients with class I bialveolar protrusion and minimal anterior crowding, treated by extraction of four first premolars with conventional sliding mechanics. After superimposition of 3D-virtual maxillary models before and after treatment using best-fit method, 3D-virtual mandibular model at each stage was placed into a common coordinate of superimposition using 3D-bite information, which resulted in 3D-indirect superimposition for mandibular dentition. The changes in mandibular dental and arch dimensional variables were measured with Rapidform 2006 (INUS Technology). Paired t-test was used for statistical analysis. Result: The anterior teeth moved backward, displaced laterally, and inclined lingually. The posterior teeth showed statistically significant contraction toward midsagittal plane. The amounts of backward movement of anterior teeth and forward movement of posterior teeth showed a ratio of 6 : 1. Although the inter-canine width increased slightly (0.8 mm, P<0.05), the inter-second premolar, inter-first molar, and inter-second molar widths decreased significantly with similar amounts (2.2 mm, P<0.05; 2.3 mm, P<0.01; 2.3 mm, P<0.001). The molar depth decreased (6.7 mm, P<0.001) but canine depth did not change. Conclusion: A new 3D-indirect superimposition of the mandibular dentitions using best-fit method and 3D-bite information can present a guideline for virtual treatment planning in terms of tooth position and arch dimension.

• 대한치과의사협회지
• /
• 제11권4호
• /
• pp.277-280
• /
• 1973

The author observed the changes of dental arch dimensions and compared spae-maintainer group with non-space-maintainer group after primary tooth extraction. The results were as follows 1) The rate of growth of dental arch of expeirmental group in intercanine width and in inter-1st molar width was more rapid than that of the control group. 2) Arch length is almost no dimensions but it was slightly decreased in lower arch. 3) Dental arch growth and tooth eruption were stimulated by space-maintainer appliance, so it is the best way to replace a new appliance at least once a year. 4) It is thought that satisfactory conclusions in this observation must be researched successively until the mixed dentition completes.

• 대한치과교정학회지
• /
• 제49권6호
• /
• pp.349-359
• /
• 2019

Objective: The aim of this study was to analyze three-dimensional (3D) changes in maxillary dentition in Class II malocclusion treatment using arch wire with continuous tip-back bends or compensating curve, together with intermaxillary elastics by superimposing 3D virtual models. Methods: The subjects were 20 patients (2 men and 18 women; mean age 20 years 7 months ${\pm}$ 3 years 9 months) with Class II malocclusion treated using $0.016{\times}0.022-inch$ multiloop edgewise arch wire with continuous tip-back bends or titanium molybdenum alloy ideal arch wire with compensating curve, together with intermaxillary elastics. Linear and angular measurements were performed to investigate maxillary teeth displacement by superimposing pre- and post-treatment 3D virtual models using Rapidform 2006 and analyzing the results using paired t-tests. Results: There were posterior displacement of maxillary teeth (p < 0.01) with distal crown tipping of canine, second premolar and first molar (p < 0.05), expansion of maxillary arch (p < 0.05) with buccoversion of second premolar and first molar (p < 0.01), and distal-in rotation of first molar (p < 0.01). Reduced angular difference between anterior and posterior occlusal planes (p < 0.001), with extrusion of anterior teeth (p < 0.05) and intrusion of second premolar and first molar (p < 0.001) was observed. Conclusions: Class II treatment using an arch wire with continuous tip-back bends or a compensating curve, together with intermaxillary elastics, could retract and expand maxillary dentition, and reduce occlusal curvature. These results will help clinicians in understanding the mechanism of this Class II treatment.

• 대한소아치과학회지
• /
• 제26권3호
• /
• pp.507-512
• /
• 1999

혼합치열기의 소아환자의 경미한 하악 전치부의 총생을 해결하는 문제와 하악 제 2 유구치의 조기 상실로 인한 하악 제 1 대구치의 근심경사 그리고 이에 따른 제 2 소구치의 맹출 공간 부족 등을 해소하기 위한 여러 가지의 방법들이 시도되어왔지만 저마다 그 술식의 적용범위나 방법 등에는 많은 어려움 들이 있어왔다. 이 연구의 목적은 이런 선택의 어려움을 가만하여 실제 임상에서 보다 간편하고 환자의 불편감을 줄여줄 수 있는 한 방법으로 Lip Bumper를 이용한 술식을 소개하고 그 적용례를 통하여 성공과 실패 사례들을 소개함으로써 임상가들에게 보다 유익한 정보를 주기 위함이다.

• 대한치과교정학회지
• /
• 제35권1호
• /
• pp.23-34
• /
• 2005

본 연구에서는 III급 수술-교정 치료 방법에 영향을 미치는 치열 상의 요소를 파악함으로써 술전 교정시 상악 소구치 발치와 비발치의 판단에 필요한 임상적 정보를 얻고자 골격성 III급 부정교합 환자의 수술-교정 치료시 흔히 선택되는 상악 제1소구치 발치로 치료된 군과 비발치로 치료된 군 간의 치료전/후 상/하악 개별 치아 이동 양상과 치열궁 폭경의 변화 양상을 비교 분석하였다 이를 위하여 비발치로 III급 수술-교정 치료를 마친 환자 (24명) 와 술전교정 치료시 상악 제1소구치가 발치된 환자 (31 명)의 치료 전/후 모형 상에서 개개 치아의 근원심/협설측 각도 변화와 상/하 치열궁 폭경의 변화를 측정한 후, 두 군 사이의 교정적 치아 이동 양상을 비교 분석한 후 상/하 치열궁의 조화를 이루는데 필요한 치열궁 폭경의 변화와 이에 기여하는 치아 변위와의 관계를 분석하기 위하여 상관 분석과 회귀 분석을 시행한 결과 발치 군은 비발치 군에 비하여 상악 치열궁 폭경의 감소가 컸으며 이는 상악 구치의 inclination 감소에 크게 영향 받은 것으로 관찰되었다. 하악 치열에서는 inclination의 증가와 폭경의 증가가 있었으나, 비발치/발치군간의 차이는 유의하지 않았다 본 연구의 결과 결론적으로 III급 수술-교정 치료시 술전 상악 소구치 발치는 상악 구치부 치열궁 폭경의 감소에 크게 영향을 미치므로, 상악 소구치 발치에 대한 판단은 상/하악 치열궁의 폭경 및 구치부 경사도 문제와 연계하여 고려해야 할 사항으로 생각되었다.

• 대한치과교정학회지
• /
• 제23권4호
• /
• pp.475-483
• /
• 1993

The purpose of this study was to investigate the treatment effects on anterior crossbite patients using chin cap and labiolingual arch appliance. In the present study, I statistically evaluated measurement values on a cephalogram before and after treatment form twenty anterior crossbite cases. The results were as follows: 1. In the craniofacial patterns, cranial base increased after treatment. 2. In the maxillo-mandibular relationship, ANB and Facial convexity significantly increased. 3. In the denture patterns, occlusal plane, Ul to FH and Overjet significantly increased. On the contrary overbite decreased significantly. Lower incisors inclined lingually. 4. In the soft tissue profile changes, lower lip protrusion was signifacantly improved.