Journal of the korean academy of Pediatric Dentistry
/
v.50
no.2
/
pp.142-154
/
2023
The canine tooth is important both functionally and aesthetically, being positioned between the anterior and posterior teeth. The upper canine has the longest eruption path, forming in the deepest part of the maxillary bone and often experiencing eruption disorders, leading to significant aesthetic and functional issues. Early detection and management of canine impaction are crucial in pediatric dentistry, which focuses on tooth growth and eruption. The prevalence of maxillary canine impaction ranges from 1.1% to 3.0%. In Western populations, palatal impaction is twice as common as labial impaction, while some Korean studies report more labial impaction. Maxillary canine impaction occurs more frequently in women and is associated with various factors such as structural obstacles, pathological conditions in surrounding tissues, developmental abnormalities, and genetic factors. Labial displaced canines are linked to narrow maxillary intercanine width, total dental crowding, and skeletal Class III malocclusion. Maxillary palatal displaced canine impaction is more prevalent in patients with familial agenesis of lateral incisors or conical supernumerary lateral incisors. Understanding these factors aids in early diagnosis and appropriate intervention for canine tooth impaction, ensuring optimal oral health and aesthetics.
The purpose of this study was to evaluate changes in soft tissue chin thickness and to investigate correlations between hard and soft tissues measurements after orthodontic treatment conducted by premolars extraction and incisor retraction. The sample consisted of 35 female adults with Angle classification class I or class II division 1 malocclusion. Using lateral cephalometric radiographs taken before and after treatment, hard and soft tissue structures were measured and reproducible six landmark on soft chin tissue were used to locate the various points of soft tissue contour of the chin. The res에ts were as follows : 1. There were signigicant correlations between pretreatment B-B', Pm-Pm' and pretreatment vortical skeletal measurements such as $MP{\perp}HP,\;MP{\perp}PP$, ALFH and between a-a', b-b', Me-Me' and measurements of sym-physeal morphology such as SL, SW, PL. 2. There were significant decreases at B-B', Pm-Pm' and significant increases at a-a', b-b' between pre-and posttreatment mea surements. 3. There were significant correlations among soft tissues changes and hard tissue changes except for changes at B-B' and the range of correlation coefficient was about 0.3-0.4. 4. There were significant differences at ${\Delta}UI-VP,\;LI{\perp}, and B-B' measurements between subgroups divided by posttreatment Pog-Pog' changes. 5. There were significant differences at ${\Delta}overbite,\;NPog{\perp}HP,\;and\;Me-Me'$ measurements between subgroups divided by posttreatment Me-Me' changes.
Considering the skeletal class III malocclusion that complains of mandibular prognathism, there have been some studies of the mandibular change for comparing the changes of pre operative with post operative state. Nowadays it is common to do the orthognathic 2-jaw surgery for the correction of the maxillary deficiency, the post operative stability and the esthetics. We compare and analyze the changes of soft tissue around the nose and the lip with the changes in the direction and the amount of maxilla. Patients who were diagnosed as maxillofacial deformity and received orthognathic surgery of both jaws at Yongdong Severance hospital from 2001 through 2003 were included in this study. Their lateral cephalograms were analyzed, and the post operative change of hard tissue and soft tissue were studied. Upon analyzing the preoperative cephalograms and 6 month post operative cephalograms, there were significant in the vertical change of Labialis superius(Ls) and Stomion(Stm) in soft tissue in relation to the vertical change of skeletal landmarks (Anterior Nasal Spine, Subspinale, Prosthion, Incision Superious). In addition, there were no significance in horizontal movement of the skeletal landmarks among groups. In terms of hard tissue landmarks, group 3(maxillary posterior impaction and advancement surgery group) showed significantly greater change in the vertical movement of Anterior Nasal Spine(ANS), Subspinale(A), Prosthion(Pr), and Incision Superious(Is) compared with other groups. In terms of soft tissue change, group 3 showed more significant change in the vertical movement of Ls and Stm. This study calculated the changes of the skeletal and soft tissue landmarks in order to act as a guide in planning and performing the surgery and as a reference in predicting the postoperative change of facial appearance.
Three-dimensional finite element model was made from adult skull to find desirable direction of retraction force to treat skeletal class II malocclusion. The retraction force of 400g was applied to the first molar. The direction of the force application was $23^{\circ}$ downward, parallel, $23^{\circ}$ upward and $45^{\circ}$ upward to the occlusal plane. The stress distribution and the displacement within the maxilla were analyzed by three-dimensional finite element method. The findings obtained were as follows: 1. Maxillary first molar was displaced posteriorly and inferiorly in $23^{\circ}$ downward, parallel, $23^{\circ}$ upward retraction but it was displaced posteriorly and superiorly in $45^{\circ}$ upward retraction. 2. ANS, A point and prosthion were moved posteriorly and inferiorly and pterygomaxillary fissure was moved posteriorly and superiorly. Clockwise rotation of maxilla occurred when retraction force was applied. 3. The degree of clockwise rotation of maxilla was greatest when the force was applied $23^{\circ}$ upward to the occlusal plane and was least when the force was applied $23^{\circ}$ downward to the occlusal plane. 4. Large tensile stress appeared in maxillary first molar and alveolar bone and the infraorbital region of maxilla when the force was applied $23^{\circ}$ downward to the occlusal plane. Tensile stress was smaller as the direction of force move upward. 5. Large compressive stress was appeared in maxillary first molar and infraorbital region in $45^{\circ}$ upward case and large compressive stress occurred in the posterior part of maxilla as the retraction force was upward.
Objective: To investigate the dentoskeletal factors which may predict soft-tissue chin strain during lip closure. Methods: The pretreatment frontal and lateral facial photographs and lateral cephalograms of 209 women (aged 18-30 years) with Angle's Class I or II malocclusion were examined. The subjects were categorized by three examiners into the no-strain and strain groups according to the soft-tissue chin tension or deformation during lip closure. Relationships of the cephalometric measurements with the group classification were analyzed by logistic regression analysis, and a classification and regression tree (CART) model was used to define the predictive variables for the group classification. Results: The lower the value of the overbite depth indicator (ODI) and the higher the values of upper incisor to Nasion-Pogonion (U1-NPog, mm), overjet, and upper incisor to upper lip (U1-upper lip, mm), the more likely was the subject to be classified into the strain group. The CART showed that U1-NPog was the most prominent predictor of soft-tissue chin strain (cut-off value of 14.2 mm), followed by overjet. Conclusions: To minimize strain of the soft-tissue chin, orthodontic treatment should be oriented toward increasing the ODI value while decreasing the U1-NPog, overjet, and U1 upper lip values.
The purpose of this study was to compare the postoperative stability and relapse according to 2 different fixation methods after bilateral sagittal split ramus osteotomies in mandibular prognathic patients. Tweenty one patients with Class III dental and skeletal malocclusion who were treated with bilateral sagittal split ramus osteotomy were selected for this retrospective study. We classfied the patients into two groups according to the fixation methods of bony segments after osteotomies. Group W (n = 10) had the bone segments fixed with nonrigid wire and Group S (n = 11) had bicortical screws inserted in the gonial area through a transcutaneous approach. Cephalometric radiographs were taken preoperatively, immediate postoperatively and more than six months postoperatively in each patient. After tracing the cephalometric radiographs, various parameters were measured. Before surgery, both groups were balanced with respect to linear and angular measurements of craniofacial morphology. Mean posterior sagittal setback amounts of the mandibular symphysis was 8.6 mm in the wire group and 6.79 mm in the rigid group, Six months postoperatively, the wire group had 33.1% relapse of the mandibular symphysis and 22.8% in the rigid group relapse. Both groups experienced changes in the orientation and configuration of the mandible. It is thought that Rigid screw fixation is a more stable method than nonrigid wire fixation for maintaining mandibular setback after sagittal split ramus osteotomy.
This study was carried out in order to find out the soft tissue profile changes associated with maxillary incisor retraction in Angle's class I malocclusion patients. For this study fifty two female adult patients (Maximum Retraction Group 23, Minimum Retraction Group 29) who received orthodontic treatment were chosen. Following conclusions were obtained by analysing the changes of soft tissue and hard tissue before and after treatment. 1. When considering the mean changes of soft tissue and hard tissue, UP, LIP, Ls, Li (p<0.001), Point B, Si (p<0.01), Point A, Ss (p<0.05) were significant posterior movement in Maximum Retraction Group and UIP (p<0.001), LIP, Ls, Li (p<0.01), Point B, Si (p<0.05) were significant posterior movement in Minimum Retraction Group. 2. When considering the correlations between hard tissue and soft tissue changes, greater correlations were found in Minimum Retraction Group between UIP and Ls (p<0.01), Point A and Ss, UIP and Li, Point B and Si (p<0.05) than Minimum Retraction Group. 3. Correlations (p<0.01) were found between upper incisor retraction and posterior movement of the upper and lower lip in Thin Lip-Thickness Group, whereas no significant correlations were found in Thick Lip-Thickness Group. 4. Mean changes of the soft tissue thickness subsequent to incisor retraction were increased (p<0.01) in upper lip (Ls-Ls'), whereas no changes were found in lower lip.
Journal of the Korean Association of Oral and Maxillofacial Surgeons
/
v.35
no.5
/
pp.329-334
/
2009
Objective: To evaluate the ratio between bone-contact length and inter-segmental length of the rigid fixation screw used in bilateral sagittal split ramus osteotomy (BSSRO) for mandibular setback. Material and Methods: Records of 40 patients with Class III malocclusion were selected. 20 of them had BSSRO, while the other 20 had BSSRO with maxillary LeFort I osteotomy. All of the patients had three noncompressive bicortical screws inserted at the gonial angle through transcutaneous approach. Two screws were inserted antero-posteriorly above inferior alveolar nerve and one screw was inserted below. The lengths of bone-contact and that of inter-segmental part were measured using cone-beam computed tomography. Ratio between these two measured lengths was calculated. Results: Both bone-contact and inter-segmental lengths were longer in BSSRO group than in BSSRO with maxillary LeFort I osteotomy group. Ratio of bone-contact to inter-segmental length was lower in BSSRO group than in BSSRO with Lefort I group. Both bone-contact and inter-segmental lengths were longer at the antero-superior position than at the inferior position. However, their ratio showed little difference. Conclusion: This study suggest that stability of screws in BSSRO group was greater than in BSSRO with Lefort I group. Stability of screws at the antero-superior position was greater than at the inferior position. Ratio of bone-contact to inter-segmental lengths was 0.2 in average.
Purpose: This study evaluated the postoperative stability of counter clockwise rotation of the mandibular plane in anterior openbite patients, who have had one jaw surgery performed. Methods: This study includes patients with skeletal class III malocclusion accompanied by anterior openbite among the patients who have had BSSRO performed, resulting in counter clockwise rotation of the mandibule. We excluded the patients with genioplasty and segmental surgery, and included 23 patients who underwent BSSRO. Results: We found no statistical significance between the amount of counter clockwise rotation in the mandible in the Pearson correlation test. Also, there was no significant difference between Group 1 (< $3^{\circ}$) and Group 2 (> $3^{\circ}$). Conclusion: This study evaluated the amount of horizontal relapse, and the degree of relapse. Stable results were obtained. Although there was no statistical significance between the degree of openbite and the amount of horizontal relapse, the group with a greater amount of openbite had a greater amount of relapse.
On, Sung Woon;Han, Min Woo;Hwang, Doo Yeon;Song, Seung Il
Journal of the Korean Association of Oral and Maxillofacial Surgeons
/
v.41
no.5
/
pp.224-231
/
2015
Objectives: The purpose of this study was to evaluate changes in the pharyngeal airway space and hyoid bone position after mandibular setback surgery with bilateral sagittal split ramus osteotomy (BSSRO) and to analyze the correlation between the amount of mandibular setback and the amount of change in pharyngeal airway space or hyoid bone position. Materials and Methods: From January 2010 to February 2013, a total of 30 patients who were diagnosed with skeletal class III malocclusion and underwent the same surgery (BSSRO) and fixation method in the Division of Oral and Maxillofacial Surgery, Department of Dentistry at the Ajou University School of Medicine (Suwon, Korea) were included in this study. Lateral cephalograms of the 30 patients were assessed preoperatively (T1), immediately postoperatively (T2), and 6 months postoperatively (T3) to investigate the significance of changes by time and the correlation between the amount of mandibular setback and the amount of change in the airway space and hyoid bone position. Results: Three regions of the nasopharynx, oropharynx, and hypopharynx were measured and only the oropharynx showed a statistically significant decrease (P<0.01). A significant posterior and inferior displacement of the hyoid bone was found 6 months after surgery (P<0.01). Analysis of the correlation between the amount of mandibular setback and the amount of final change in the airway space and hyoid bone position with Pearson's correlation showed no significant correlation. Conclusion: In this study, the oropharynx significantly decreased after mandibular setback surgery, and changes in the surrounding structures were identified through posteroinferior movement of the hyoid bone during long-term follow-up. Therefore, postoperative obstructive sleep apnea should be considered in patients who plan to undergo mandibular setback surgery, and necessary modifications to the treatment plan should also be considered.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.