• Journal of Periodontal and Implant Science
• /
• 제35권3호
• /
• pp.761-776
• /
• 2005

The purpose of the present study was to examine the relationship between the form of the clinical crowns in the maxillary anterior segment and the clinical feature of gingiva such as morphological characteristics and the gingival thickness. Fifty periodontally healthy subjects were clinically examined regarding the probing depth, the thickness of the free gingiva, and the width of the keratinized gingiva. From study models of the maxillary anterior region, the width at cervical third(CW) and the length(CL) of the clinical crown, the papillary height, and the gingival angle of the 6 anterior teeth were measured. Each tooth was classified into 4 groups (longnarrow, NL; narrow, N; wide, W; short-wide, WS) according to CW/CL ratio and all the data were compared between groups NL and WS using independent t-test. Stepwise multiple regression analysis was performed for each tooth region with the gingival thickness at the level of sulcus bottom, the width of keratinized gingiva, and gingival angle as the dependent variables. As the results, the NL group of the upper anterior teeth displayed, higher papilla height, and narrower keratinized gingiva, more acute gingival angle resulting in pronounced "scalloped" contour of the gingival margin, compared to the WS group. There was no significant difference between groups NL and WS with respect to probing depth and the gingival thickness. The regression analyses demonstrated that the gingival thickness in central incisors was significantly associated to the mesio-distal width and bucco-lingual width of the crown, and labial probing depth. The width of keratinized gingiva was significantly associated with labial probing depth in central incisors and with proximal probing depth and gingival angle in lateral incisors, and with labial and proximal probing depth, and gingival angle in canines. The gingival angle was significantly associated with papillary height and CW/CL ratio and additionally with proximal probing depth in central incisors, with the width of keratinized gingiva in lateral incisors, and with labial probing depth and the width of keratinized gingiva in canines. These results indicate that the form of clinical crown in upper anterior region could influence the clinical feature of gingiva and the influencing factors might be different according to the tooth region.

• 대한치과교정학회지
• /
• 제11권2호
• /
• pp.143-150
• /
• 1981

Casts of 180 Korean male and female with normal occulsion of early permanent dentition (from dental age of Hellman III C, to IV A) were studied to measure the mesiodistal crown diameters and to calculate the coefficients of correlation between the teeth. From the study, the following conclusions were made: 1. Mesiodistal dimension of maxillary central incisors, canines, first molars and mandibular canines, first premolars, second premolars and first molars of male are larger than that of female. 2. Korean teeth are roughly intermediate between those of American Caucasian and those of American Negro. 3. In both sexes, the relation between the first and second premolars appeared highly correlated not only in the maxillary arch but also in the mandibular arch, and the relation between the central incisor and lateral incisor appeared highly correlated in the mandibular arch. 4. The relation between the maxillary and mandibular first premolars appeared highly correlated in both sex, and the relation between the maxillary canine and mandibular canine in male as well as between the maxillary central incisor and mandibular central incisor in female appeared highly correlated.

• Journal of Periodontal and Implant Science
• /
• 제27권1호
• /
• pp.235-248
• /
• 1997

The purpose of this study was to investigate the width of attached gingiva of 414 subjects with healthy gingiva, or early stage of gingivitis. We compared the differences according to the tooth location, age (Yonger group : $14{\sim}30$, Older group : $31{\sim}67$) and gender. In addition, we compared the width of attached gingiva in the subjects with less than 2 sites of gingival recession($Re{\leq}2$) and the subjects with more than 3 sites of gingival recession($Re{\geq}3$) to study the relationship between the gingival recession and the width of attached gingiva. The results were as follows : 1. The width of keratinized gingiva was widest in maxillary incisors($5.3{\pm}1.4mm$) and narrowest in mandibular right 1st bicuspid and mandibular right and left 2nd molars($3.5{\pm}1.1mm$). 2. The width of attached gingiva was widest in maxillary right central incisor($3.8{\pm}1.5mm$) and narrowest in mandibular right 2nd molar($1.2{\pm}1.0mm$). 3. In the comparison between the age groups, the width of keratinized in older group was significantly (p<0.05) wider than that in younger group in maxillary right and left 1st bicuspids, mandibular right and left 1st and 2nd molars, maxillary right and left cuspids and mandibular right 1st bicuspid. There was no significant difference in the width of attached gingiva between the two groups except for maxillary right and left 1st molars and maxillary left 2nd molar. 4. In the comparison between male group and female group, in maxillary right and and left lateral incisors and cuspids, mandibular right and left cuspids and 1st bicuspids, the width of attached gingiva in female was significantly(p<0.05) wider than that in male group. 5. In the comparison between the Re 3 group and Re 2 group, there was no significant difference except for maxillary right and left 2nd molars and maxillary left 1st molar. 6. The frequency of gingival recession was m the order of mandibular right 1st bicuspid(16.6%), maxillary right 1st bicuspid(13.7%), maxillary and mandibular left 1st bicuspids (13.4%), mandibular left cuspid (10.5%), maxillary left and mandibular right cuspids(10.1%) and maxillary right cuspid(7.9%).

• 대한치과교정학회지
• /
• 제53권2호
• /
• pp.106-115
• /
• 2023

Objective: To evaluate the null hypothesis that there is no difference in a set of clinical predictors of potentially impacted canines between low-risk patients with and without displaced canines. Methods: The normal canine position group consisted of 30 patients with 60 normally erupting canines ranked in sector I (age, 9.30 ± 0.94 years). The displaced canine group comprised 30 patients with 41 potentially impacted canines ranked in sectors II to IV (age, 9.46 ± 0.78 years). Maxillary lateral incisor crown angulation, inclination, rotation, width, height, and shape, as well as palatal depth, arch length, width, and perimeter composed a set of clinical predictors, which were evaluated on digital dental casts. Statistical analyses consisted of group comparisons and variable correlations (p < 0.05). Results: There was a significant association between sex and mesially displaced canines. Unilateral canine displacement was more prevalent than bilateral displacement. The crown of the maxillary lateral incisors was significantly angulated more mesially and rotated mesiolabially in low-risk patients with displaced canines, who also had a shallower palate and shorter anterior dental arch length. Lateral incisor crown angulation and rotation, as well as palatal depth and arch length, were significantly correlated with the canine displacement severity. Conclusions: The null hypothesis was rejected. Maxillary lateral incisor angulation inconsistent with the "ugly duckling" stage as well as a shallow palate and short arch length are clinical predictors that can significantly contribute to the early screening of ectopic canines in low-risk patients.

• 대한소아치과학회지
• /
• 제31권3호
• /
• pp.495-500
• /
• 2004

치내치(dens invaginatus)는 치아 발생 과정 중 경조직이 석회화되기 전에 법랑질 상피가 함입되어 생기는 치아 기형이다. 치내치는 함입된 정도에 따라 다양한 형태학적 변이를 보이는데 이러한 기형은 미생물이 침입할 수 있는 통로가 될 수 있어 치수조직의 괴사와 치근단 농양 또는 치은 농양의 원인이 된다. 이러한 경우 근관의 복잡한 해부학적 형태 때문에 근관 치료가 매우 어렵다. 본 증례는 상악 좌측 측절치의 동통을 주소로 내원한 두 명의 환아들에 관한 것이다. 첫 번째 증례는 수산화 칼슘제재를 이용한 근관치료를 시행하여 양호한 결과를 얻었고 두 번째 증례는 치아를 발거하였다. 발거된 치아는 미세전산화 단층촬영을 이용하여 해부학적 형태를 살펴보았기에 보고하는 바이다.

• 대한치과교정학회지
• /
• 제26권6호
• /
• pp.657-666
• /
• 1996

Orthopantomogram is commonly used to evaluate root parallelism. "Good parallelism" between roots is widely accepted as one of the guidelines of a successful orthodontic treatment. In case there was a large angle between crown axis and root axis, and if we valued only the position of crown in establishing occlusal relationship without considering of the situation of root, the problem of root arrangement between adjacent teeth would be occurred. The estimate of root parallelism in mesiodistal direction before and after orthodontic treatment must be emphasized. The intent of this study was to determine the clinical importance and correlation of the angle between crown axis and root axis. Orthopantomograms of 105 orthodontic patients being treated in Yonsei university were used in this study. Twenty-eight teeth in both maxilla and mandible were selected and analyzed quantitively to evaluate the angle between crown axis and root axis, and obtain the correlationship among the individual teeth. The results are as follows: 1. Among the teeth presenting normal distribution, the maxillary right canine showed the largest mean value( $5.73{\pm}4.42^{\circ}$), which was composed of the crown-root angles, and the mandibular left lateral incisor showed the smallest mean value( $0.60{\pm}3.76^{\circ}$). 2. The crown-root angles of the maxillary incisors and the first molars, and the mandibular central incisors and the first molars didn't show normal distribution and the ranges of these angles were dispersed. 3. Significant differences were present between the crown axis and the root axis except for lower first premolars. (p<0.05) 4. No significant difference was present for the crown-root angle between right and left side, (p<0.05) 5. No significant difference was present for the crown-root angle between male and female except for lower left first premolar. (p<0.05) 6. In the upper right quadrant, significant correlations were present between crown-root angles of the central incisor and lateral incisor, lateral incisor and canine. In the upper left quadrant, significant correlations were present between crown-root angles of the central incisor and lateral incisor. In the lower right quadrant, significant correlations were present between crown-root angles of the central incisor and lateral incisor, first molar and second molar. In the lower left quadrant, significant correlations were present between crown-root angles of the central incisor and lateral incisor, lateral incisor and canine, first molar and second molar. (p<0.05)

• 대한치과교정학회지
• /
• 제27권2호
• /
• pp.297-313
• /
• 1997

본 연구는 부산대학교병원 치과교정과에 내원하여 교정 및 악교정수술 복합치료를 시행 받은 환자 총 42명 중 하악에만 수술을 받은 환자 18명과 상하악에 동시에 수술을 받은 환자 24명을 대상으로 하였으며 초진, 수술전, 수술직후, 수술 6개월 경과후의 측모두부방사선규격사진을 채득하고 투사도를 작성하여 계측하였다. 골격, 치아 및 연조직에 대한 분석을 통하여, 수술후 경조직 변화에 따른 연조직 변화를 편악수술군과 양악수술군에서 비교하고 술전교정치료시에 지침이 될 수 있는 상하악절치의 경사도에 대해 연구하여 다음의 결과를 얻었다. 1. 수술직후 양악수술군에서는 상악골 및 상악전치, 상순의 전방과 상방으로의 이동이 두드러졌다. 양군 모두에서 하악골 및 하악절치는 후방이동하였고 하순의 두께가 증가되었으나 두군 사이에 통계학적으로 유의성있는 차이는 없었고 전안모고경은 양악수술군에서 더 많이 감소되었다(p<0.05). 수술 6개월 경과후 편악수술군에서는 상악절치가 1.44mm 전방이동하였고, 하악절치와 하악골도 각각 1.26mm, 1.43mm 전방이동하였으나 양악수술군에서는 유의한경조직의 변화가 없었다. 2. 수술직전과 수술 6개월 경과후 양악수술군에서 상악골의 수평적 변화와 상순의 Sn, SLS, LS의 수평적 변화사이의 상관계수가 0.70, 0.73, 0.70이었고 변화율은 79%, 80%, 82%였다. 하악골의 수평적 변화와 하순의 LI, ILS의 수평적 변화사이의 상관계수는 각각 0.93, 0.94였고 변화율은 89%, 101%였다. 편악수술군에서는 하악골의 수평적 변화와 하순의 LI, ILS의 수평적 변화사이의 상관계수는 각각 0.73, 0.83이었고 변화율은 각각 92%, 104%였다. Pog과 Pog', Me와 Me' 사이의 수평적 변화율은 양군 모두 1:1 이었다. 3. 수술직전과 수술 6개월 경과후 양악수술군에서 상악절치의 수평적 변화와 상순의 Sn, SLS, LS의 수평적 변화사이의 상관계수는 0.72, 0.76, 0.75, 변화율은 각각 57%, 58%, 59%였다. 하악절치의 수평적 변화와 하순의 LI, ILS의 수평적 변화사이의 상관계수는 양악수술군에서 0.93, 0.90, 편악수술군에서 0.71, 0.89였고 변화율은 양악수술군에서 76%, 87%, 편악수술군에서 75%, 85%였다. 4. 편악수술군에서 악골의 전후방 부조화와 상하악절치 경사도사이 에 FMIA = 57.48-2.17 ANB, Ul-SN = -75.02+2.17 SNB의 회귀방정식을 구할 수 있었으며 결정계수는 각각 0.63, 0.63이었다. 양악수술군에서는 SNB와 FMIA, SNB 및 ANB와 U1-SN사이에 회귀방정식을 구할 수 있었으나 결정계수가 0.13에서 0.19사이로 낮아 유의성은 없었다.

• 대한소아치과학회지
• /
• 제27권1호
• /
• pp.122-134
• /
• 2000

각화치은, 부착치은의 폭경, 치은열구의 깊이에 대해 성인에서는 많은 연구가 있었으나 아동에서의 연구는 드물었기 때문에, 유치열기, 혼합치열기 및 영구치열기의 모든 치아에 대하여 아동의 협측 각화치은 및 부착치은의 폭경과 치은열구 깊이에 대한 정상치를 구하고, 악골의 발육 및 치아의 맹출과의 관련성을 고찰하며, 점막치은 문제의 발현빈도를 조사하고자 하였다. 결론은 다음과 같다. 1. 유치열의 부착치은 폭경은 상악 유측절치 및 유견치에서 각각 3.50mm, 3.55mm로 최대값을, 하악 제1유구치에서 1.34mm로 최소값을 나타내었다. 영구치열의 경우에는 상악 측절치에서 3.00mm로 최대값을, 하악 제1소구치에서 0.55mm로 최소값을 나타내었다. 상하악 동명치아 비교시 상악 치아가 하악 치아보다 더 큰 값을 나타내었고, 남녀간 차이에는 특별한 규칙이 발견되지는 않았다. 2. 연령증가에 따른 부착치은 폭경의 변화 양상은 유치열의 경우 유견치, 제1유구치, 제2유구치에서 6세부터 증가하였다. 영구치의 경우 남자에서는 하악 중절치와 상악 제 1대구치의 측정값만이 연령에 따른 증가 추세를 나타냈으나(p<0.05), 여자에서는 상하악 중절치 측절치 및 상악 제1대구치에서 통계적으로 유의성 있는 각화치은 폭경의 증가 추세를 관찰할 수 있었다(p<0.05). 3. 치아교대기에서 부착치은 폭경의 차이는 남자 상악 중절치를 제외한 모든 경우에 유치에서의 측정값이 영구치에서의 측정값보다 큰 것으로 나타났다(p<0.05). 4. 6제부터 12세까지는 각화치은의 폭경과 치은열구의 깊이는 대부분 유치 초기값보다 그 계승영구치 최종값이 더 높은 값을 나타냈으나(p<0.05), 부착치은의 폭경에서는 유치 초기와 그 계승영구치 최종값사이에 통계적으로 유의성 있는 차이가 나타나지 않았다. 5. 점막치은 문제 발현 빈도는 남녀에 상관없이 유치열은 상하악 제 1유구치가, 영구치열은 상하악 모두 제 1소구치가 최고치를 나타냈으며 유치에서보다 그 대응 계승영구치에서 그 빈도가 더욱 높게 나타났다. 연령증가에 따라 점막치은 문제의 발현 빈도는 유치열, 영구치열에서 모두 감소하였으나, 하악 제1유구치, 하악 영구 견치, 제1, 제2소구치의 경우 연령의 증가와 상관없이 비슷하게 유지되거나 증가하는 경향을 보였다.

• 대한치과교정학회지
• /
• 제47권5호
• /
• pp.323-333
• /
• 2017

Orthodontic treatment of a complex case that involves retained deciduous mandibular second molars with missing permanent successors is challenging. Usually, congenitally missing teeth are manifested with other dental anomalies that further complicate orthodontic treatment, such as retained deciduous teeth, impactions, transpositions and peg-shaped lateral incisors. Even though the long term prognosis of the retained deciduous tooth is not fully predictable, if the teeth are in good condition, the patient and clinician may incline towards a decision to preserve the deciduous teeth as long as possible. This case report demonstrates that deciduous teeth, in this case the mandibular second molars and maxillary canine, can be incorporated into final occlusion with clinically stable long-term results.

• 대한치과교정학회지
• /
• 제4권1호
• /
• pp.57-61
• /
• 1974

The patient, a girl of 19 years in good health, had a class I malocclusion. The maxillary left centra1 incisors and both lateral incisors had already erupted. But the space for the right central incisor was partially closed by the mesial drifting of the neighboring teeth. The caused a shift in the midline and a cross-bite relation on the incisors. X-ray examination revealed the presence of the right central incisor in the alveolar bone and odontoma just above the crown of the right central incisor. After enough space for the impacted incisor was created in the dental arch with a open-coil spring the rectangular incision was made. Removing the odontoma uncovered the flat surface of the labial aspect of the incisor. During the tooth had erupted of its own accord, any unnecessary force had been imposed on the tooth. When it was decided that the tooth should be brought out by the mechanical device, the gold cast onlay with hook was used and run a light elastic between this hook and the main arch wire. Finally the tooth was brought down to the arch level. The result was excellent. Fortunately the esthetic problem and any detrimental effects on the psychological make-up could be avoided.