拔牙与非拔牙矫治前后牙弓宽度的变化

目的:比较拔牙与非拔牙矫治前、后牙弓前后部宽度的变化。方法:选择50例患者的矫治前后模型作为研究对象,其中25例采取拔除4个第一前磨牙的矫治方法,为拔牙组;25例采取非拔牙矫治,为非拔牙组。观察2组矫治前、后牙弓前后部宽度的变化,采用SPSS11.0软件包进行配对t检验和χ2检验。结果:2组上颌尖牙间宽度均增大,但组间无统计学差异(P>0.05);2组下颌尖牙间宽度均增大,且组间有显著统计学差异(P<0.01);2组第二磨牙间宽度均无变化。结论:与非拔牙矫治相比,拔牙矫治并不会引起牙弓的缩窄。     

恒牙期Ⅲ类错拔牙与非拔牙矫治的初步研究

目的分析恒牙期Ⅲ类错拔牙组和非拔牙组矫治前后软硬组织的变化。方法恒牙期Ⅲ类错成功矫治完成后的79名患者,其中36人接受了拔牙治疗;43人接受了非拔牙治疗。治疗前后X线头颅侧位片应用Winceph7.0软件测量。统计学分析采用SPSS10.0统计学软件进行,两组治疗效果的评价采用配对t检验。结果治疗后两组均出现上切牙唇倾、下切牙舌倾、覆盖增加、覆减小。上颌骨和下颌骨的改变无统计学意义,但上下颌骨间的位置关系及面高发生了变化。结论恒牙期Ⅲ类错治疗以牙性改变为主,非拔牙组面中部软硬组织突度增加,上唇突度增加;拔牙组下唇突度减小,侧貌均得到明显改善。     

Damon拔牙与非拔牙矫治前后牙弓宽度变化的研究

目的：比较分析采用Damon矫治技术对牙列拥挤病例进行拔牙与非拔牙矫治的牙弓形态变化。方法：15例中度牙列拥挤病例,使用Damon3矫治器进行非拔牙矫治;15例重度牙列拥挤病例,使用Damon3矫治器进行拔牙矫治。对治疗前后的记存模型进行测量分析,讨论牙弓宽度改变特点。结果：采用Damon矫治技术矫治牙列拥挤的拔牙与非拔牙病例均可取得较好的效果,拔牙组上、下颌尖牙间宽度增大,有统计学意义;非拔牙组上、下颌前磨牙宽度以及上颌第一磨牙间宽度增大,有统计学意义。结论：拔牙组牙弓宽度改变主要与牙齿移动方向有关,非拔牙组牙弓宽度改变与拥挤存在部位以及拥挤程度有关。     

拔牙矫治与非拔牙矫治对牙槽骨宽度影响的比较研究

目的 研究拔牙矫治与非拔牙矫治对牙槽骨宽度的影响。方法选正畸临床非拔牙病例和拔除四颗第一双尖牙病例各32例，分别对其矫治前和矫治后模型的下颌尖牙间、上颌尖牙间、下颌第二磨牙间及上颌第二磨牙间牙槽骨宽度进行测量，测量点为牙根牙槽部之最突点，测量数据经统计学分析。结果矫治后，拔牙组比非拔牙组下颌、上颌前部宽度分别增加了1．57mm、1．64mm（P均〈0．01），而后部宽度的差异无统计学意义。矫治前后，非拔牙组牙槽骨前后部宽度变化不明显（P均〉0，05）；而拔牙组下颌前部宽度增加了2．47mm（P〈0，001），上颌前部宽度增加了2．07mm（P〈0．01），而后部宽度的变化不明显（P均〉0.05）。结论非拔牙矫治对牙槽骨前、后部宽度无影响；拔牙矫治对牙槽骨后部宽度也无影响，但对前部宽度不但未引起降低，反而有明显的增宽。拔牙矫治导致牙弓缩窄、从而影响美观的结论有待探讨。     

不同拔牙模式正畸矫治对成年女性牙弓宽度和软组织正貌的影响

目的：研究不同拔牙模式对安氏Ⅱ1错牙合成年女性治疗前后牙弓宽度和面部软组织正貌的影响。方法：将40例安氏Ⅱ1错牙合需拔牙矫治的成年女性患者随机分为两组。 A组拔除上颌2颗第一前磨牙,下颌拔除2颗第二前磨牙,B组拔除4颗第一前磨牙。分析比较两组病例治疗前后牙弓宽度和面部软组织正貌指标的变化。结果：正畸治疗后,组内比较显示两组病例上下颌尖牙间宽度均增加,上下颌第一磨牙间宽度均减小,差异有统计学意义（P＜0.05）;组间比较仅下颌尖牙和下颌第一磨牙间宽度变化有统计学意义（P＜0.05）,B组下颌尖牙宽度增加量大于A组,B组下颌第一磨牙牙弓宽度减小量小于A组。治疗前后比较,两组病例在面宽、口裂宽、下颌角间宽、容貌面长和鼻下颏下距的差异均无统计学意义（P＞0.05）。Pearson相关性分析显示牙弓宽度与软组织正貌指标之间无相关关系（P＞0.05）。结论：安氏Ⅱ1错牙合病例正畸矫治后成年女性软组织正貌的变化不受拔牙模式影响,不同拔牙模式仅影响矫治后牙弓宽度的变化。     

拔牙和非拔牙矫治对颊廊影响的研究

目的 研究拔牙和非拔牙矫治对颊廊的影响.方法 随机选取安氏Ⅰ类错(牙合)拔牙矫治患者和不拔牙矫治患者各25例,在其矫治前后的牙(牙合)模型上,分别对上下尖牙区和磨牙区唇颊面最突出的位置进行牙弓宽度的测量,同时在其矫治前后面部正位像上,测量笑容宽度和上颌可见牙列宽度,计算颊廊系数.所有数据均经统计学分析.结果 非拔牙组矫治前后牙弓宽度变化无统计学意义.拔牙组矫治后上、下颌尖牙间宽度分别增加了2.87 mm和1.30 mm(P＜0.05),但上下颌磨牙间宽度的变化无统计学意义.两组治疗前后颊廊系数变化均无统计学意义.结论 对于安氏Ⅰ类错(牙合)患者,拔牙和不拔牙矫治对颊廊均无明显的影响.     

利用Tip-Edge第一期矫治技术非拔牙矫治安氏Ⅱ类1分类错[牙合]的临床研究

目的：应用Tip-Edge I期矫治技术对治疗非拔牙安氏Ⅱ类1分类错[牙合]进行矫治,并对矫治机理进行探讨。方法：临床筛选病例12例。矫治前后拍摄头颅侧位定位片,并对相关指标进行模型测量。治疗前后相关头影测量项目测量值输入计算机,用SAS软件包对各测量值进行配对t检验。结果：Tip-Edge I期矫治结束后,上颌切牙倾斜（U1-SN,U1-Apog）明显减小,而下颌切牙的倾斜明显增加（P〈0.01）覆牙合超[牙合]显著减小。上颌第一磨牙远中移动1.5 mm,远中直立3.5°,有显著性差别。模型测量分析表明上颌尖牙间宽度和磨牙宽度显著增加。下颌尖牙间的宽度无显著变化。下颌磨牙宽度显著增加。结论：利用Tip-Edge I期技术能够非拔牙矫治处于生长发育期的安氏Ⅱ类1分类错[牙合]。对处于生长发育期具有良好生长型（水平生长型）和生长潜力的患者较易取得良好的效果。     

非拔牙矫治前后牙弓宽度改变的模型测量分析

目的 研究非拔牙矫治患者矫治前后牙弓宽度的改变.方法 选取牙弓轻度拥挤、采用非拔牙简单排齐的安氏I类错(牙合)患者77例,在模型上测量矫治前后尖牙间及磨牙间的牙弓宽度,并将测量结果进行配对t检验.结果 矫治后上颌尖牙间宽度增加(1.00 1.79)mm,下颌尖牙间宽度增加(0.51±1.66)mm,矫治前后上、下颌尖牙间宽度的改变有统计学意义(P＜0.05).矫治后上颌磨牙间宽度增加(0.23±1.36)mm,下颌磨牙间宽度增加(0.14±1.53)mm,矫治前后上、下颌磨牙间宽度改变无统计学意义(P＜0.05).结论 安氏I类非拔牙矫治患者矫治后上、下颌尖牙间宽度均有增加,而上、下颌磨牙间宽度相对稳定.     

拔牙与不拔牙矫正治疗对牙弓宽度的影响

目的比较拔牙与不拔牙矫正治疗对牙弓宽度的影响。方法选择25例拔除第一或第二前磨牙的正畸患者,25例未拔牙的正畸患者,测量治疗前后的牙颌模型,记录上、下颌牙弓宽度,其中包括尖牙间、前磨牙间及磨牙间宽度,比较拔牙与不拔牙矫正治疗对牙弓宽度的影响。结果上、下颌尖牙牙弓宽度的比较中,拔牙组比不拔牙组大,上颌大1.79mm,下颌大1.95mm,(P<0.01)。磨牙区牙弓宽度差异无显著性。结论拔牙治疗不会导致尖牙区宽度的减小。     

拔牙与非拔牙矫治骨性Ⅰ类错牙合畸形对口咽气道的影响

目的　比较拔牙矫治与非拔牙矫治对Ⅰ类错牙合畸形患者口咽气道容积差异,评估拔牙矫治对口咽气道的影响。方法　本研究选取骨性Ⅰ类错牙合畸形患者40例,其中拔牙矫治（拔除4个前磨牙）及非拔牙矫治各20例,采用锥形束CT（CBCT）头影测量技术,就矫治前、后3个骨性测量项目、4个牙性测量项目及口咽气道大小进行测量比较。配对t检验比较拔牙矫治组与非拔牙矫治组在矫治前（T0）与矫治后（T1）口咽气道容积差异,两样本t检验评估拔牙与非拔牙矫治对口咽气道容积的影响。结果　无论拔牙矫治组还是非拔牙矫治组,矫治后面中部长度及下颌骨有效长度均较矫治前增大（P＜0.01）;在拔牙矫治组,矫治后上切牙唇倾度、下切牙唇倾度、上切牙凸距及下切牙凸距均较矫治前减小（P＜0.01）;拔牙矫治组与非拔牙矫治组,矫治前后口咽气道容积及气道最窄处面积的改变,两组间比较无统计学意义（P＞0.05）。拔牙矫治组8例患者矫治后口咽部最狭窄区域相对牙合平面位置发生改变,而非拔牙矫治组6例患者矫治后口咽部最狭窄区域相对牙合平面位置发生改变。结论　拔牙矫治Ⅰ类错牙合畸形——拔除4个前磨牙,内收上前牙并不影响口咽气道大小。     

Mandibular dental changes following serial and late extraction of mandibular second premolars

Objectives:To determine changes in occlusal curves and dental tipping occurring from mandibular second premolar serial extraction, early extraction of deciduous mandibular second molars with missing second premolars, and late second premolar extraction compared with untreated controls.Materials and Methods:Information was collected from 85 subjects at three time points: T0, prior to serial extraction; T1, after serial extraction and drift prior to orthodontic treatment, and pretreatment for the late premolar extraction patients; and T2, posttreatment. Untreated age- and gender-matched controls were used for comparison. Three occlusal curves were measured on digitized mandibular casts, and dental tipping was assessed using lateral cephalograms.Results:At T0, there were no significant differences among groups. At T1, there was significant steepening of Monson''s sphere and the curve of Wilson between early and late extraction and control groups. At T2, the differences in Monson''s sphere and the curve of Wilson were fully corrected. At T1, there were significant differences in the tipping of mandibular 6''s, 4''s, and 3''s between the early extraction groups compared with the late extraction and control groups. At T2, these differences in tipping were fully corrected. There were no differences in mandibular incisor tipping between groups at T1 or T2.Conclusions:Serial extraction produced steeper occlusal curves and significant tipping of mandibular first molars, first premolars, and canines after extraction and physiologic drift (T1). Accentuated occlusal curves and tooth tipping were fully corrected following orthodontic treatment (T2). Mandibular incisor position was unchanged by serial or late second premolar extraction.     

拔牙与非拔牙的骨性安氏Ⅲ类双颌手术前后的硬组织变化

目的:探讨已行双颌手术的骨性安氏Ⅲ类错患者治疗前、正颌手术前正畸后和治疗完成后拔与不拔上颌第一前磨牙的上、下颌骨硬组织结构差异。方法:研究对象为均已行上颌骨Le Fort I型前移和下颌骨矢状劈开后退术的骨性安氏Ⅲ类错畸形伴上颌骨发育不足和下颌骨发育过度的患者。研究对象被分成两组:术前正畸拔除上颌第一前磨牙组15例,未拔牙组16例。摄取治疗前(T1)、正颌手术前正畸后(T2)、治疗完成后(T3)的头颅侧位定位片分析测量9个指标值,采用SAS 8.02软件包对数据进行团体t检验。结果:治疗前(T1)拔牙与非拔牙组上牙槽角(SD-SN)有显著差异(P<0.05)。正颌手术前正畸后(T2)下中切牙角(L1-MP)和覆盖有显著差异(P<0.05)。治疗后(T3)下中切牙角(L1-MP)有显著差异(P<0.05)。其他各测量项目均无统计学差异,P>0.05。结论:拔牙组在治疗前骨组织的结构形态上上牙槽骨较非拔牙组更前突,通过术前拔牙正畸内收上前牙长轴后得以改善。正颌手术前正畸后拔牙组下前牙去代偿较非拔牙组更明显,下前牙更直立。     

A long-term study of the relationship of third molars to changes in the mandibular dental arch

The purpose of this study is to determine the relationship of third molars to changes in the mandibular dental arch. The sample for this study consisted of four groups and subgroups. The groups consisted of premolar extraction treated, nonextraction treated with initial generalized spacing, nonextraction treated, and serial extraction untreated subjects. The subgroups were divided into persons who had mandibular third molars that were either impacted, erupted into function, congenitally absent, or extracted at least 10 years before postretention records. The mean postretention time interval was 13 years, with a range of 10 to 28 years. The mean postretention age was 28 years 6 months, with a range of 18 years 6 months to 39 years 4 months. Two-way analysis of variance with repeated measures was used to compare the changes over time (before treatment, at end of active treatment, and after retention) of groups and third molar subgroups. With time, mandibular incisor irregularity increased while arch length and intercanine width decreased. The eruption patterns of mandibular incisors and first molars were similarly dispersed in all groups studied. The findings between the subgroups in which mandibular third molars were impacted, erupted into function, congenitally absent, or extracted 10 years before postretention records revealed no significant differences between any of the subgroups for the parameters studied. No significant differences in mandibular growth were found between the third molar subgroups; this suggests that persons with third molars erupted into satisfactory function do not have a significantly different mandibular growth pattern than those whose third molars are impacted or congenitally missing. In the majority of cases some degree of mandibular incisor crowding took place after retention, but this change was not significantly different between third molar subgroups. This finding suggests that the recommendation for mandibular third molar removal with the objective of alleviating or preventing mandibular incisor irregularity may not be justified.     

不同前磨牙拔除模式对安氏Ⅰ类病例下唇软组织的影响

目的：通过对拔除第一前磨牙和拔除第二前磨牙安氏Ⅰ类错病例治疗前后下唇软组织变化的比较,探讨两种拔牙模式的异同。方法：选取50例安氏Ⅰ类（骨性Ⅰ类）临界病例,随机分为两组,拔4个第一前磨牙和4个第二前磨牙病例各25例,按性别、年龄、骨面型、拥挤度严格配对,对治疗前后的头颅侧位X线片软组织的14项指标进行测量。结果：在相对X、Y轴的绝对值测量中,治疗前两组无任何统计学差异;治疗后第一前磨牙拔除组线距的明显增长表现在垂直方向上,而第二前磨牙拔除组表现在在水平方向上。在软组织测量项目中,治疗前第一前磨牙拔除组颏唇角和下唇厚度均大于第二前磨牙拔除组,组间差异有统计学意义（P〈0.05）。矫治后,拔除第一前磨牙组下唇倾角、下唇长、下唇基部厚度、颏唇沟深度增加,而颏唇角、下唇基角、下唇厚、下唇突度、下唇突凹点相对E线的距离减小。拔除第二前磨牙组颏唇角、下唇倾角、下唇基角、下唇基部厚度均增加,其中下唇倾角和下唇基部厚度的变化明显;下唇长、下唇突度、下唇突凹点相对E线的距离减少,而下唇厚基本不变。结论：拔除第一和第二前磨牙组在治疗前后下唇的各项软组织角度和线距变化均无统计学的差别。     

不同前磨牙拔除模式对安氏Ⅰ类病例上唇组织的影响

目的通过对拔除第一前磨牙和拔除第二前磨牙安氏Ⅰ类错病例治疗前后上唇软组织变化的比较,探讨2种拔牙模式的异同。方法选取50例青少年安氏Ⅰ类错患者为研究对象,根据拔除牙位分为拔除第一前磨牙组和拔除第二前磨牙组,每组25例患者。对2组患者治疗前后头颅侧位X线片上的15项软组织测量指标进行测量和统计分析。结果1）在上唇各点相对X轴和Y轴的线距上,2组患者治疗后A′-X和UL-X的变化差异均存在统计学意义（P<0.05）。2）在软组织角度和线距的测量项目上,2组患者治疗后上唇长度、UL-EP、A′-EP的变化明显（P<0.05）,但2组患者软组织角度和线距的变化差异均无统计学意义（P>0.05）。结论拔除第一前磨牙和第二前磨牙对上唇均有明显改变,但2种拔牙模式之间没有明显差别。     

不同前磨牙拔除模式对安氏Ⅰ类病例软硬组织B点的影响

[摘要] 目的：通过不同拔牙模式研究安氏I类错牙合患者治疗前后软硬组织B点变化的影响。方法：本研究选择50例安氏Ⅰ类临界病例,包括拔除第一前磨牙组和第二前磨牙组各25例。分别测量14项矫治前后头颅侧位片的软硬组织指标。组内和组间比较采用T检验。结果：(1)矫治前,两组患者在水平和垂直距离差异没有统计学意义;矫治后,各点垂直方向上的变化在拔除第一前磨牙组中存在显著差别(P<0.05),而软硬组织B点水平方向上的变化在拔除第二前磨牙组中相对明显。（2）硬组织变化方面,治疗前两组患者差异无统计学意义;治疗后,两组患者下切牙轴倾度、SNB角变化无统计学意义,NB的线距减少且差异有统计学意义(P<0.01 );拔除第一前磨牙和第二前磨牙组间差异无统计学意义。（3）软组织变化方面,治疗前,两组患者的下唇倾角、下唇翻卷度和B'-EP差异无统计学意义,但颏沟倾角差异有显著的统计学意义( P<0.001);治疗后,两组患者软组织显著改善;矫治前后两组间差异无统计学意义。结论：正畸拔牙矫治显著改变软、硬组织B点,但两种不同拔牙模式间对软硬组织的改变没有统计学意义。     

上颌拔牙矫治对骨性Ⅲ类错牙合畸形正颌术前牙弓宽度影响研究

目的 评价骨性Ⅲ类错牙合畸形患者正颌术前正畸治疗中拔除与不拔除上颌第一前磨牙对牙弓横向宽度的影响,为是否在术前正畸中拔除上颌前磨牙提供一个参考指标。方法 选择2007年1月至2012年7月在大连市口腔医院接受正畸-正颌联合治疗的骨性Ⅲ类错牙合畸形患者28例,其中12例术前正畸采取拔牙矫治（拔牙组）,16例采取不拔牙矫治（非拔牙组）。对两组病例正畸治疗前后的模型进行牙弓宽度对比研究。结果 经过术前正畸治疗,拔牙组较非拔牙组的上颌后段牙弓宽度减小明显,差异有统计学意义（P < 0.05）;拔牙组与非拔牙组的下颌牙弓中段及后段宽度均有增加,但两组差异无统计学意义（P > 0.05）。结论 在骨性Ⅲ类错牙合畸形的正畸-正颌外科联合治疗中,拔除上颌第一前磨牙有利于术前正畸有效去除后牙代偿,协调上下牙弓间横向关系,为正颌手术创建良好条件。     

Mandibular second premolar extraction--postretention evaluation of stability and relapse

The dental casts and cephalometric radiographs of 46 patients, treated with mandibular second premolar extraction and edgewise orthodontic mechanotherapy, were evaluated for changes over a minimum 10-year postretention period. The sample was divided into two groups: early (mixed dentition) extraction of mandibular second premolars and late (permanent dentition) extraction of mandibular second premolars. Results showed no difference in long-term stability between the two groups. Arch length and arch width decreased with time and incisor irregularity increased throughout the postretention period. No predictors or associations could be found to help the clinician in determining the long-term prognosis in terms of stability. The sample was regrouped according to the postretention degree of incisor irregularity. Statistically significant differences in cephalometric measurements were found between the minimally crowded group and the moderately to severely crowded group.     

不同前磨牙拔除模式对安氏Ⅰ类病例软硬组织A点影响的研究

目的　比较拔除第一、第二前磨牙矫治安氏Ⅰ类错牙合病例治疗前后软硬组织A点的变化。方法　选择50例安氏Ⅰ类（骨性Ⅰ类）临界病例为样本,其中拔4个第一前磨牙和4个第二前磨牙病例各25例,按性别、年龄、骨面型、拥挤度严格配对,对治疗前后的头颅侧位X 线片软硬组织的14项指标进行测量。统计学分析方法采用组内配对t检验、组间成组t检验及相关分析。结果　①在相对X、Y轴的绝对值测量中,治疗前2组无统计学差异;治疗前后的各点第一前磨牙拔除组在垂直方向上的变化存在显著性差异(P<0.05),而拔除第二前磨牙组在水平方向上的变化更明显。②在软组织角度和线距的测量项目中,治疗前的上唇翻卷度、上唇倾角第一前磨牙拔除组均小于第二前磨牙拔除组;治疗后2组均出现上唇倾角、上唇到E线的距离增加;但2组在各项测量项目的变化上没有组间差别。③在硬组织角度和线距的测量项目中,治疗前第一前磨牙拔除组的颌凸角较大;治疗后2组各测量值均减少,但2组无组间差异。④相关分析:统计结果显示第一、第二前磨牙拔除组软硬组织A点的变化均呈正相关关系（P＜0.01)。结论　拔除第一和第二前磨牙软硬组织A点均有明显改变,两种拔牙模式之间没有统计学差别。     

Posttreatment and postretention changes following orthodontic therapy.

This investigation was performed to determine the changes which occurred in treated orthodontic cases out of retention. The material consisted of 103 cases, of which 74 cases were treated nonextraction and 29 were treated with the extraction of four first premolars. The treatment was accomplished by the full-banded edgewise bioprogressive technique. Five measurements were taken: intercanine, inter-first premolar, intersecond premolar and inter-first molar widths, and incisor to molar distance. The measurements were made on the mandibular arch of the pretreatment, posttreatment, and prostretention casts. The postretention model was obtained a minimum of one year after all retaining devices were removed with an average of 5.2 years. The following conclusions were drawn from the changes in dimensions: 1. The intercanine width was expanded during treatment, but had a strong tendency to return to or close to its original pretreatment width in both nonextraction and extraction cases. 2. The inter-first premolar width showed the greatest treatment increase in width with only a minimal amount of postretention decrease. 3. The second premolar width for nonextraction cases showed a significant amount of increase with a slight tendency for postretention decrease. 4. The second premolar width for extraction cases showed a decrease with treatment and a slight continued decrease postretention. 5. The intermolar width of nonextraction cases showed a significant increase in width with treatment. The extraction cases showed a significant decrease with treatment. However, there were no changes in either extraction or nonextraction cases postretention. 6. The incisor to molar distance decreased with treatment and had a slight tendency to continue to decrease postretention.