• The Journal of Advanced Prosthodontics
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• 제9권5호
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• pp.321-327
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• 2017

PURPOSE. The aim of this study was to investigate dental arch dimensions and to classify arch shape in Korean young adults. MATERIALS AND METHODS. The sample included 50 Koreans with age ranging from 24 to 32 years. Maxillary and mandibular casts were fabricated using irreversible hydrocolloid and type III dental stones. Incisor-canine distance, $incisor-1^{st}$ molar distance, $incisor-2^{nd}$ molar distance, intercanine distance, $inter-1^{st}$ molar distance, and $inter-2^{nd}$ molar distance in both the maxillary and mandibular arch were measured using a three-dimensional measuring device. The dental arch was classified into three groups using five ratios from the measured values by the K-means clustering method. The data were analyzed with one-way analysis of variance. RESULTS. Arch lengths (IM2D, $incisal-2^{nd}$ molar distance) were 44.13 mm in the maxilla and 40.40 mm in the mandible. Arch widths (M2W, inter $2^{nd}$ molar width) were 64.12 mm in the maxilla and 56.37 mm in the mandible. Distribution of the dental arch form was mostly ovoid shape (maxilla 52% and mandible 56%), followed by the V-shape and the U-shape. The arch width for the U-shape was broader than for the other forms. CONCLUSION. This study establishes new reference data for dental arch dimensions for young Korean adults. The most common arch form is the ovoid type in the maxilla and mandible of Koreans. Clinicians should be aware of these references and classify arch type before and during their dental treatment for effective and harmonized results in Koreans.

• 대한치과교정학회지
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• 제14권2호
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• pp.263-272
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• 1984

This study was undertaken to examine the extent to which tooth size and jaw size each contribute to dental crowding. Two groups of dental casts were selected on the basis of dental crowding. One group, consisting of 94 pairs of dental casts (46 males and 48 females) with normal occlusion. A second group, consisting of 84 pairs of dental casts (98 males and 46 females) with crowding. The results were as follows. 1. Means and standard deviations of the two groups were used to compare the two groups. 2. Significant differences were observed between two groups on the basis of tooth size, arch dimension and arch perimeter. 3. Between noncrowded group and crowded group, was crowded group was found to have large troth size than noncrowded group, while smaller arch dimension and perimeter. 4. Significant differences were observed between males and females on the basis of tooth size, arch dimension and arch perimeter. 5. Author found ideal arch shape of normal occlusion.

• 대한치과교정학회지
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• 제42권1호
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• pp.47-54
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• 2012

Objective: To determine and compare the frequency distribution of various arch shapes in ethnic Malays and Malaysian Aborigines in Peninsular Malaysia and to investigate the morphological differences of arch form between these two ethnic groups. Methods: We examined 120 ethnic Malay study models (60 maxillary, 60 mandibular) and 129 Malaysian Aboriginal study models (66 maxillary, 63 mandibular). We marked 18 buccal tips and incisor line angles on each model, and digitized them using 2-dimensional coordinate system. Dental arches were classified as square, ovoid, or tapered by printing the scanned images and superimposing Orthoform arch templates on them. Results: The most common maxillary arch shape in both ethnic groups was ovoid, as was the most common mandibular arch shape among ethnic Malay females. The rarest arch shape was square. Chi-square tests, indicated that only the distribution of the mandibular arch shape was significantly different between groups (p = 0.040). However, when compared using independent t-tests, there was no difference in the mean value of arch width between groups. Arch shape distribution was not different between genders of either ethnic group, except for the mandibular arch of ethnic Malays. Conclusions: Ethnic Malays and Malaysian Aborigines have similar dental arch dimensions and shapes.

• 대한치과의사협회지
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• 제37권8호통권363호
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• pp.608-613
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• 1999

During diagnostic process of the orthodontic patients, it is not unusual to find palatally erupted canines. Palatally erupted canines are related with the positional abnormalities rather than the tooth size/arch-length discrepancies. It is very important to conserve the original arch shape during traction of palatally erupted canines to their proper position. On the following case, the patient was diagnosed as malocclusion with palatally erupted canines, and were treated by 0.9mm auxiliary arch wire during traction of ectopic canines for maintenance of the original arch shape.

• 대한치과교정학회지
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• 제14권1호
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• pp.93-101
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• 1984

Human dental arches are very various in their sizes and dimensions as well as forms, so, it is very difficult to describe the shape of human dental arches as a criterion, and, further, to construct the preformed arch wires fit to them. In this study for solving these problems, the shape of eighty Korean normal lower dental arches were studied, and nine theoretical two-parameter catenary curves were derived, which were representative of all of the sample. Test were conducted which demonstrated that these nine cattenary curves would correspond with a reasonable degree of accuracy to all of the dental arches, lower and upper.

• 대한치과보철학회지
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• 제36권1호
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• pp.166-182
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• 1998

The purposes of this study are to evaluate the Korean mandibular dental arch and classify the mandibular dental arch shape and size based on the incisal angle, canine angle, inter second molar width and height. In this study the mandibular study models were fabricated using irreversible hydrocolloid impression material from 225 volunteers with a mean age 23.62 (range 19-29). And the study models were measured with 3-dimensional measuring device and the mandibular dental arch was classified by means of K-means clustering method and visual inspection, then obtained data were analyzed with t-test for the statistical analysis. The results were as follows ; 1. The average canine height was 5.19mm(s.d. 1.17) in both sex, 5.34mm in male, and 4.95mnm in female. And the sexual difference was significant($0). 2. The average second molar height was 39.81mm(s.d. 2.44) in both sex, 40.19mm in male, and 39.21mm in female. And the sexual difference was significant($0). 3. The average inter-canine width was 27.16mm(s.d. 1.78) in both sex, 27.41mm in male, and 26.77mm in female. And the sexual difference was significant($0). 4. The average inter-first molar width was 46.93mm(s.d. 2.67) in both sex, 47.72mm in male, and 45.7mm in female. And the sexual difference was significant($0). 5. The inter-second molar width was average 56.09mm(s.d. 3.01) in both sex, 57.24mm in male, and 54.32mn in woma. And the sexual difference was significant($0). 6. The arch form was classified into three shapes based on the incisal and canine angle. V-shape showed $124.88^{\circ}$ of incisal angle and $141.64^{\circ}$ of canine angle, U-shape showed $152.76^{\circ}\;and\;125.35^{\circ}$, and O-shape showed $138.03^{\circ}\;and \;33.66^{\circ}$ respectively. Each shape distribution was that the V-shape was 14.2%, the U-Shape was 14.7%, and the O-shape was 71.1% of the 225 study models. 7. It was thought that the use of second molar width is more reasonable than height for classifying the dental arch size. The arch size was classified into four sizes based on the second molar width. Size 1 showed range of 42.24-48.23mm, size 2 showed 48.24-54.23mm, size 3 showed 54.24-60.23mm, and size 4 showed 60.24-66.23mm respectively. Each arch size distribution was that the size 1 was 1.3%, the size 2 was 27.1%, the size 3 was 63.6%, and the size 4 was 8.0% of the 225 study models.

• 대한치과교정학회지
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• 제36권1호
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• pp.45-54
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• 2006

최근 안모의 심미성이 중요시되면서 구순 돌출로 인한 비심미성을 해소하고자 내원하는 양악 치조골 전돌자의 수가 증가하는 추세이다. 그러나 이러한 환자에 대한 연구는 많지 않으며 특히 모형을 이용한 연구는 극히 적다. 모형을 이용하는 연구는 주로 손으로 직접 계측하거나 2차원 평면에서 컴퓨터를 이용하여 측정하였으나 근래에 3차원 레이저 스캐너가 도입되면서 모형을 이용한 연구를 좀 더 빠르고 간편하면서도 정확하게 할 수 있게 되었다. 이 연구는 3차원 디지털 모형을 이용하여 양악 치조골 전돌자의 치열궁 특성을 알아보기 위한 것이다. 양악 치조골 전돌자 20명과 정상교합자 20명을 대상으로 치아 크기, 치열궁 폭경 및 치열궁 길이, 치열궁과 구개의 형태를 비교하여 본 결과 양악 치조골 전돌자는 정상교합자보다 치아 크기가 크고, 하악 견치간 폭경 및 제1소구치간 폭경이 크며 치열궁 길이가 길었다. 그리고 치열궁 형태와 구개 형태에서 정상교합자와 차이를 보였다.

• 대한치과교정학회지
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• 제17권2호
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• pp.279-287
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• 1987

This study was designed to get the Knowledges of the dental arch shapes of Koreans. The subjects consisted of 101 individuals with normal occlusion. The results were as follows, 1 Author found the ideal arch shape of normal occlusion 2 The regression curve and equations of normal occlusion were obtained from SPSS 3 Ideal arch form and superimposition form were obtained by Versa-cad.

• 대한치과교정학회지
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• 제14권1호
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• pp.115-125
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• 1984

A comparative study was undertaken to investigate the collapse of maxillary dental arch and palate in unilateral cleft lip and palate individuals. The material for this study consisted of 39 subjects with repaired unilateral cleft lip and palate (30 males, 9 females). The measurements of unilateral cleft lip and palate individuals were compared with the measurements of normal individuals (30 males, 30 females). All the subjects were in the mixed dentition stage and the mean age was almost the same. The following conclusions were obtained. 1. A large number of the maxillary dental arch of the unilateral cleft lip and palate individuals showed ${\Omega}$-shape, and the arch length was shorter than that of normal individuals. The intermolar width did not show significant difference between cleft group and group, but the intercanine width was mcuh smaller than that of normal individuals. 2. The palate of the unilateral cleft lip and palate subjects showed shorter and shallower form than that of normal subjects. 3. The palatal area of the unilateral cleft lip and palate subjects was smaller than that of normal subjects, and the cleft side area was much smaller than the opposing side area. 4. There was no significant sexual difference in measurements of maxillary dental arch and palate of the unilateral cleft lip and palate subjects.

• 대한소아치과학회지
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• 제51권1호
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• pp.55-65
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• 2024

This study aimed to assess the accuracy of tooth widths, intermolar widths, and arch lengths acquired through two intraoral scanners, including iTero Element Plus Series (Align Technology, Santa Clara, CA, USA) and Trios 4 (3Shape, Copenhagen, Denmark), specifically on mixed dentition. A total of 30 subjects were divided into 2 groups, each undergoing both alginate impressions and intraoral scanning using either the iTero or Trios scanner. The plaster models were measured with a caliper, while the digital models were measured virtually. In the iTero group, all tooth width measurements exhibited differences compared to the plaster values, except for maxillary left lateral incisors (p = 0.179), mandibular right (p = 0.285), and left (p = 0.073) central incisors. The Trios group did not display significant differences in any of the tooth width measurements. Intermolar width comparisons for both groups indicated differences, except for mandibular primary canine to primary canine values (p = 0.426) in the iTero group. Regarding arch length, the mandibular anterior, maxillary right, and left arch lengths in the iTero group demonstrated larger caliper values than those of iTero. Conversely, in the Trios group, all parameters showed smaller caliper values, especially in upper anterior, maxillary right, mandibular right, and mandibular left arch lengths with significance (p = 0.027, 0.007, 0.003, and 0.047, respectively). Despite the differences between the two groups, digital models might be clinically suitable alternatives for plaster models. Pediatric dentists should carefully assess these differences, as a comprehensive evaluation would result in precise orthodontic treatment planning and favorable outcomes for young patients with mixed dentition.