Objective: This study was performed to investigate the influences of extraction and nonextraction treatment on smile esthetics by measuring dental arch width changes. Methods: Pretreatment and posttreatment study models of 30 first premolar extraction cases and 30 nonextraction cases were randomly selected to determine whether extraction treatment results in narrow dental arches, and a consequent unaesthetic smile. Arch widths were measured from the cusp tips of the canines and the first molars. Posterior arch widths were also measured at a constant arch depth derived by averaging randomly chosen nonextraction models. Results: The intercanine widths increased significantly in the extraction sample, whereas the intermolar widths decreased significantly. The arch width at a standardized arch depth was significantly wider in the extraction subjects. Conclusion: These results elucidate that constriction in arch width is not a materialized consequence of extraction treatment. It leads to postulate that an esthetically compromising effect from narrow dental arches on smile is hardly anticipated with extraction treatment.
The purpose of this study was to investigate the pretreatment and posttreatment dentofacial characteristics of non-extraction patients with Class I malocclusion. And to compare this result with matched non-orthodontic normal occlusion and Class I premolar extraction patients. Such comparison might help identify morphologic characteristics of the non-extraction patients. Initial and final cephalometric evaluation were compared in a sample of 22 patients with Class I malocclusions treated in non-extraction manner with edgewise appliance and MEAW The mean age of the total population was 14 years 9 months and the average treatment time was 2 years 8 months. 32 landmarks were located and digitized on each cephalogram. From these landmarks, 24 linear and angular dimension were obtained. Student's t-test were used to compare the pretreatment - posttreatment results, Nonextraction - Normal groups, and nonextraction Extraction groups. Significance was predetermined at $p{\leq}0.05$. The results were as follows. 1. Before treatment, the mean value of the $ODI\;was\;69.9^{\circ},\;APDI\;was\;82.1^{\circ},\;CF\;was\;152^{\circ},\;EI\;was\;152^{\circ}$ in the non-extraction groups. 2. The skeletal pattern of the non-extraction groups were similar with non-orthodontic normal groupsr, but the non-extraction groups had larger interincisal angle. 3. Comparison between groups treated with and without extraction indicated at pretreatment, the extraction groups had more protrusive lips, smaller interincisal angle, and EI. 4. After treatment, there was no significant changes in the skeletal pattern of the non-extraction groups, but uprighting of the maxillary and mandibular first molar and decrease of the interincisal angle were seen.
Journal of Dental Rehabilitation and Applied Science
/
v.29
no.2
/
pp.119-126
/
2013
The concept of extraction in orthodontic treatment has been changed many times. Even today, criteria of extraction or nonextraction is still changing. In this study, changes depending on the evaluator's perception of treatment outcomes were compared in both extraction and nonextraction cases. In this study, premolar extracted 59 patients and nonextracted 60 patients, totally 119 patients who finished orthodontic treatment in Dankook University Dental Hospital orthodontic clinic were enrolled. Evaluation sections made up of specialists and laypersons assessed soft tissue traced from lateral cephalometric radiographs with visual analogue scale before and after the treatment. And the results were statistically analyzed. Thus, the conclusions drawn are as follows: 1. Average score is 5.76 in extraction, which is larger than 5.28 of nonextraction case. Improvement of facial profile was more favorably accepted in extraction case. 2. 5.875 in the group of specialists were higher evaluation than 5.165 in the group of layperson. 3. Specialists gave significantly higher ratings in the extraction than nonextraction. 4. A higher rating in extraction case of the layperson group has no significant difference with nonextraction case. 5. Nonextraction patients were given higher ratings from specialist group. 6. A higher rating of specialist group in extraction case has no significant difference with layperson group.
Collective changes caused by orthodontic tooth movement evaluated in a specific treatment modality could give suggestive information on the specific treatment strategy. The aim of this study was to investigate retrospectively the characteristics of the orthodontic tooth movement during surgical-orthodontic treatment in order to provide an effective presurgical orthodontic treatment planning for the maxillary premolar extraction modality In the skeletal Class III malocclusion patient. Pre- and post-treatment dental casts of skeletal Class III malocclusion patients with nonextraction (N=:24) and the maxillary premolar extraction (N=31) were collected. The angulation and inclination measuring gauge(Invisitech Co. Seoul, Korea) was used to evaluate the orthodontic tooth movement. The changes in the maxillary and mandibular dental arch widths were also measured from the canines to the second molars. As a result, more palatal inclination change in the maxillary dentition was found with the premolar extraction modality than with the nonextraction modality. Linear regression analysis showed that the inter-arch width coordination was mainly due to the inclination changes of maxillary posterior teeth We conclude that the indications and proper treatment planning for surgical-orthodontic treatment in skeletal Class III malocclusion with maxillary premolar extraction could depend partly on the magnitude of the transverse inter-arch coordination especially in the maxillary dentition.
71 Class I malocclusion samples were selected and they were divided into premolar-extraction and non-extraction groups. Vertical and horizontal cephalometric evaluations on dental and soft tissue measurements were done before and after treatment. Also, treatment results in adolescent patients and adult patients were compared. The following conclusions were obtained: 1. In comparison of extraction and non-extraction groups, all the dental and soft tissue measurements, with exception of SN-MP angle, upper lip to E-line, vertical movement of upper first molar, md horizontal movement of lower first molar, showed statistically significant differences. 2. In comparison of extraction and non-extraction groups of adolescent samples, there were statistically significant differences in upper and lower incisor inclinations, horizontal dental movements from vertical reference line, positional changes in upper and lower lips, and mesial movements of upper first molar. 3. In comparison of extraction and non-extraction groups of adult samples, there were statistically significant differences in upper and lower incisor inclinations, horizontal dental movements from vertical reference line, positional changes in upper and lower lips from I-line and vertical reference line, vertical height of upper first molar, and mesial movement of lower first molar. 4. There was no statistically significant difference in SN-MP angle between extraction and non-extraction groups of both adolescent and adult samples.
This study was investigated to assess the difference of facial height and occlusal plane inclination between pre- and post-treatment in Class I malocclusion group The subjects consisted of 35 extraction patients and 30 nonextraction patient,;, and was subdivided into Group I(overbite<0mm), Group II(04mm) in reference to overbite, and adolescent group and adult group in reference to age. Lateral cephalogram was taken with standard method, traced, and digitized for each subject. The computerized statistical analysis was carried out with SAS program The results wolf as follows. 1. In both groups of extraction and nonextraction group the anterior facial height increased after orthodontic treatment but there was no significant difference(p>0.05) between each goup. 2. There was no statstical significance in change of occlusal plane inclination in adolescent group, but significant difference(p<0.05) among three subgroup in adult group. 3. In adolescent-extraction and adolescent-nonextraction group there was significant increase of anterior facial height and posterior facial height, and was superior to adult groups in posterior facial height increment. 4 In all groups upper and lower molars were uprighted to occlusal plane. This had statistically significant effect.
Journal of the korean academy of Pediatric Dentistry
/
v.28
no.3
/
pp.421-429
/
2001
Since Non-Extraction treatment in some orthodontic case shows unstable result and unfavorable profile, extraction is selected as inevitable treatment option for the harmonious profile, facial skeleton, and the stable dentition on both arches. For the achievement of proper goal, premolars, molars, sometimes incisors or canines are selected to be extracted. The first Premolar is usually extracted for relieving the crowded dentition with which the molar relations are class I to gain stable dentition and proper profile, but often results in the depression of profile or the loss of vortical dimension. On the contrary, the extracton of the second molar helps maintaining the fullness of profile and the vertical dimension, prevents additional space closural procedures which often make the procedures complicated, relieves both anterior and posterior crowding, and substitutes the extraction fossae for newly erupting 3rd molars. From the point of recurrence, the second molar extraction procedure, therefore, is more beneficial. This cases showed the good results of second molar extraction procedures in the patients with class I crowding.
The purpose of this study was to evaluate the changes of skeletodental patterns during Class II treatment and its retention period. Forty two patients of Class II malocclusion, which was treated with nonextraction or first premolar-extraction were selected and their lateral cephalograms were examined in this study. Various skeletodental changes in lateral cephalograms of pre-treatment, post-treatment and retention were measured by superimposition in reference to the cranial base for jaws, the palatal plane for maxillary teeth, and mandibular plane for mandibular teeth. The data were analyzed by paired t-test. In this study, occlusal plane showed the significant anterior downward steepening after active treatment, and remained during retention period. In the nonextraction group, maxillary incisors were retracted and extruded during treatment. Maxillary molars were extended, and mandibular molar were uprighted, with no mesial movement. In the extraction group, both maxillary and mandibular incisors were retracted and extruded. Maxillary molars were extruded and moved mesially, and mandibular molars were extruded and moved mesially with no mesial tilting. During retention period in both groups, there were tendencies of labial tipping of maxillary incisor, and mesial tipping of maxillary and mandibular molar. But the changes were not significant and most of teeth showed no change in vortical and horizontal direction.
Objective: This study was performed to evaluate functional changes of occlusion after orthodontic treatment by measuring the occlusal force (OcFr) and occlusal contact area (OcAr), and to compare OcFr and OcAr change according to premolar extractions. Methods: Data were obtained from 74 patients who had finished orthodontic treatment using fixed appliance aged between 18 and 40 years. Subjects were divided into groups who had four premolars extractions or non-extraction (Male extraction-16, Male nonextraction-18, Female extraction-19, Female nonextraction-21). All subjects were asked to bite pressure-sensitive sheets into maximum intercuspation with maximum bite force, and OcFr and OcAr were evaluated by measuring the sheet with a CCD camera. Records were taken right after debonding, 1 week, 1 month, 3 months, 6 months and 1 year after debonding. Results: OcFr and OcAr increased gradually in all groups during the 1 year retention period (p < 0.05). Male groups showed higher OcFr and OcAr than female groups throughout the retention periods (p < 0.05). There were no statistically significant differences of OcFr and OcAr between extraction and non-extraction groups in both males and females (p > 0.05). Conclusions: Occlusion was improved functionally throughout the 1 year retention, and premolar extraction did not induce a decline in the functional aspect of occlusion.
The purpose of this investigation were to evaluate facial vortical changes occurring in patients treated orthodontically with first premolar, second remolar and second molar extractions : to compare these changes with those occurring in patients treated orthodontically without extractions : and finally, to evaluate the effects of extractions in facial vortical changes. Cephalometric records of 50 male & female nonextraction patients and 88 male & female extraction patients were obtained from the department of orthodontics at Chosun University, College of Dentistry. The second molar fully erupted pPatients to have little variation according to growth were chosen as the sample for this investigation. For comparisons, the samples of 88 male & female extraction patients were subdivided into 42 first premolar extraction, 24 second premolar extraction, and 22 second molar extraction patients. Fourteen cephalometric measurements were selected to examine whether orthodontic extraction treatment led to vertical changes or not. The pretreatment and posttreatment lateral cephalographs were taken on the same radiographic unit. $SPSS/PC^+$ statistical program was used to compare and to analyze the changes between 'before & after' orthodontic treatment. The results of this study were as follows. 1. There were no statistical significances in any cephalometric measurements between 'before & after' orthodontic treatment regardless of orthodontic extractions for each group. 2. On average, the upper 6 to palatal Plane and the lower 6 to mandibular plane after orthodontic treatment were increased in all group. This means most of orthodontic mechanics are extrusive in nature. Especially, in orthodontic extraction. cases, it may be caused by orthodontic mechanics for space closure and alignments. 3. On average, in the second molar extraction group, the facial vertical dimension was increased after orthodontic treatment. It nay be induced as a result of moving the molars distally to gain enough space to correct the molar relationship and to simultaneously improve the deep bite. 4. There was no statistical significance between orthodontic extractions and facial vertical changes. This means that orthodontic extractions have no influence on facial vortical changes. 5. The cephalometric measurements with statistical significance in ficial vertical changes for each group were PP-MP, Op-MP, $\underline{1}$ to PP and $\overline{1}$ to MP.
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.