“Wits”分析法的评价

本研究的目的是通过比较Ｗｉｔｓ法与其它几项头影测量法从统计学角度反映Ｗｉｔｓ值的可靠程度。本研究的Ｘ线测位片是从我科矫治病例中随机抽样的，共１３５例，包括安氏各类错，其中男性６９例，女性６６例，均为恒牙早期，男女年龄无统计学差异。对每张Ｘ线片测量其Ｗｉｔｓ值，ＡＮＢ角，Ａ－Ｘ－Ｂ角及ＡＦ－ＢＦ距。经统计分析表明：Ｗｉｔｓ值的变异系数较大，仅次于ＡＮＢ角，说明Ｗｉｔｓ值并不优于其它测量法；经相关分析表明这四项测量值均呈高度相关，说明这几项测量值变化趋势一致，可相互替换补充使用，在一些特殊病例，如多数后牙开，牙齿严重缺损或替牙期恒磨牙及双尖牙萌出不足的情况下，功能性邪平面难以确定。因此笔者认为Ｗｉｔｓ分析法由于其基准平面─—平面的难以确定，所以有其局限性，应慎重使用，     

Wits值与ANB角在评价颌骨矢状位置关系中的价值

ＡＮＢ角与Ｗｉｔｓ值均是评价上下颌基骨矢状位置关系的重要方法。作者在对蒙古族正常儿童Ｘ线头影测量研究中发现，平面角随生长发育而减小．平面角的变化严重影响Ｗｉｔｓ值的可靠性。因此在对颌骨纵向生长发育评价及生长发育期患者矫治前后颌骨矢状位置关系的对比分析中，ＡＮＢ角比Ｗｉｔｓ值可靠。     

关于SNA,SNB,ANB及Wits值影响因素的研究

ＳＮＡ角、ＳＮＢ角、ＡＮＢ角及Ｗｉｔｓ值是口腔正畸科常用的Ｘ线头影测量项目，主要用于判断颅颌结构的矢状关系．近年来的研究发现他们受很多因素的影响．该文即利用相关分析的方法，对上述测量项目的影响因素进行系统研究，为临床正确应用提供依据．     

安氏Ⅱ、Ⅲ类错颅底与颌面形态关系的研究

颅底的生长发育影响颌面部形态。关于这种影响,国内外学者有较多争议。本项研究旨在通过对中国人安氏Ⅱ类与Ⅲ类错颅底形态的观察,对颅底与颌面形态的关系进行评价。一、材料与方法1.样本:随机选取北京地区57例12～16岁女性,分成2组。第一组,28例,远中关系,Ｗｉｔｓ≥2,为安氏Ⅱ类错组;第二组,29例,近中关系,Ｗｉｔｓ≤-4,为安氏Ⅲ类错组。2.Ｘ线片测量:拍摄定位头颅正、侧位片,硫酸纸描绘,通过数字化仪输入计算机。测量角度:ＮＳＢａ、ＳＡｒＧｏ、ＡｒＧｏＭｅ、ＳＮＡ、ＳＮＢ、ＳＮＭＰ、ＳＮＰＰ、ＳＮＯＰ;测量线距:ＳＮ、ＳＢ…     

探讨ANB角与Wits值的关系

一、材料与方法样本选用男女各 5 0例ＣｌａｓｓⅠ或ＣｌａｓｓⅡ错、骨生长型较好 (ＯＭ 8°～ 19 5°平均 11 7°)、矫治前的病人的头颅定位侧位片 ;年龄 11～ 13岁 ,平均 12 1岁。所有的Ｘ片在同一机器上拍摄 ,每张片子由同一人分别两次覆醋酸纸描绘、定点、取均值 ,测量ＡＮＢ角和Ｗｉｔｓ值 ,将数值输入计算机进行分析。根据正负Ｗｉｔｓ值将病人分为两组 :组Ⅰ ,5 4例ＡＮＢ 2°～ 9° ,正Ｗｉｔｓ值 (0～ 8ｍｍ) ;组Ⅱ ,46例ＡＮＢ 0°～ 5 5°,负Ｗｉｔｓ值 (- 10 5～ - 0 5ｍｍ)。各组分别进行ＡＮＢ角与Ｗｉｔｓ值相关分析…     

ANB角与“Wits”值在正畸临床诊断中的应用体会

在国内外采用的几十种测量分析法中，ＡＮＢ角作为评价上、下颌骨矢状位置关系的重要指标被多数分析法应用。这主要是基于前颅底平面（Ｓ－Ｎ）在生长发育过程中具有相对的稳定性，因而被运用于确定其它结构与颅底相互关系的基准平面，其鼻根点（Ｎ）至上齿槽座点（Ａ）与...     

APDI的正畸临床评价

评价ＡＰＤＩ在判断上下颌骨矢状位置关系中的应用价值。方法选取成人正常Ｈｅ６３名，通过计算机辅助的Ｘ线头影测量系统，选用Ｄｏｗｎｓ分别法进行ＡＰＤＩ与ＡＮＢ、Ｗｉｔｓ值的对比分析。结果ＡＰＤＩ能较好地反映颅骨与颌骨、颌骨与牙弓的矢状关系，其诊断特异性较好，但其影响的因素较多。     

颌骨骨型与そ型的研究

本研究的目的，是分析正常そ个体颅面结构特征及其颌骨骨型与そ型的关系。５７名具有正常咬合关系的受试者，按照Ｈａｏｓｔｏｎ的方法分为三组，１６６名Ａｎｇｌｅ错そ患者也依ＡＮＢ角的大小进行分类统计。研究结果表明，三组骨型之间在ＮＡ－ＡＰｇ、ＡＢ－ＮＰｇ、ＳＮＡ、ＳＮＢ、Ｕｌ－ＮＡ、Ｌｌ－ＮＢ各项测值间存在差异且有显著性。说明颌骨骨型与そ型并不一致，即使正常そ个体间也存在着不同的骨型。本研究结果提示，临床诊断与治疗设计时，必须识别患者的骨骼类型并以相应骨型的正常测量均值作为参照标准。     

骨性Ⅱ类错的颅底形态研究

目的用几何形态测量和传统头影测量2种方法,对Ⅱ类错的颅底形态进行研究。方法随机选取Ⅱ类与Ⅰ类错骨面型儿童的头颅定位侧位片各40张,描记颅底的9个标志点,数字化后,用Procrustes重叠法和薄板曲线法这2种几何形态测量法比较Ⅱ类与Ⅰ类错牙合的颅底形态。并用传统头影测量法对颅底的测量值进行分析。结果Ⅱ类与Ⅰ类错相比,颅底角无明显差别;后颅底发生显著变化,水平向后明显延长,伴向上的轻度抬高;前颅底区的S-SE段向前下方改变。结论Ⅱ类错的颅底形态有其自身特点;颅底形态影响Ⅱ类错的形成。     

正畸治疗前后数字化头影测量图像SN重叠方法的研究

目的验证数字化头影测量图像SN重叠方法的可靠性。方法对10例正畸患者的数字化头影测量图像进行了前颅底解剖结构重叠法、SN线重叠法和Ba-N线重叠法中Gn点位移的比较;并对正畸治疗前后两次测量和采用重叠法直接测量的SNA角、1-SN角和中切牙点与SN线距离变化的比较。结果1)前颅底解剖结构重叠法和SN线重叠法测量的Gn点位移的差异无统计学意义;2)两次测量和采用重叠法直接测量测得的SNA角、1-SN角和中切牙点与SN线距离变化的差异亦无统计学意义。结论在数字化头影重叠的过程中,重叠后的图像未改变原有图像资料的真实性和有效性,重叠后的图像能真实反映正畸临床治疗的效果。     

Beta角评价前牙反患者颌骨矢状关系的准确性分析

目的探讨Beta角判断替牙期与恒牙期前牙反[牙合]患者颅面矢状关系的可靠程度。方法应用X线头颅定位侧位片,比较替牙期与恒牙期前牙反[牙合]患者的Beta角、ANB角、Wits值和APDI指数的差异,并进行相关性和变异程度分析。结果替牙期与恒牙期前牙反[牙合]患者Beta角间差异有统计学意义（P〈0．05）;Beta角与ANB角、Wits值和APDI指数显著相关（P〈0．05）,但变异较ANB角和Wits值小,与APDI指数接近。结论Beta角可准确评价前牙反[牙合]患者的颌骨矢状关系。     

四种上下颌骨矢状位置关系评估方法的比较

目的:比较ANB角、Wits值、AFBF值和APDI四种方法评估上下颌骨矢状位置关系的稳定性及相关性。方法:随机选择50例错牙合畸形病例正畸治疗前的X线头颅侧位定位片,同时测量其ANB角、Wits值、AFBF值和APDI,测量结果进行相关性及变异度分析。结果:APDI的变异系数最小,Wits值变异系数最大;四值之间均存在相关性,以ANB角与AFBF值相关性最强。结论:每种评估方法影响因素不同,宜采用综合分析。     

Properties of the ANB angle and the Wits appraisal in the skeletal estimation of Angle's Class III patients

The aims of the present study were: (1) to investigate the statistical differences in jaw relationship assessments with the ANB angle and the Wits appraisal in Angle Class III children, and (2) to suggest guidelines for the use of these two parameters in this group of children. Seventy-five Angle Class I children with anterior crowding (male, 37; female, 38) and 96 Angle Class III children with anterior crossbite (male, 38; female, 58) were examined. All had undergone treatment that started at 8 or 9 years of age. Pre-treatment lateral cephalograms were used cross-sectionally for the analysis. The mean age was 8 years 7 months +/- 9 months in the Class I subjects, and 9 years 0 month +/- 7 months in the Class III subjects. To compare the assessments using ANB angle and the Wits appraisal in the Angle's Class III subjects, nine measured values from each individual subject were converted into Z scores in relation to the means and standard deviations of the two parameters in the Angle Class I subjects. The jaw discrepancy is assessed more severely using the ANB angle than by the Wits appraisal in these Angle Class III subjects. The paired t-test showed that the Z score of the ANB angle was significantly smaller than that of the Wits appraisal (P < 0.001). In Angle Class III subjects with a counter-clockwise mandibular rotation and a flattened occlusal plane, the ANB angle is a more critical cephalometric parameter than the Wits appraisal.     

Seven parameters describing anteroposterior jaw relationships: Postpubertal prediction accuracy and interchangeability

Seven parameters describing anteroposterior jaw relationships (the A-B plane angle, the angle of convexity, the ANB angle, the SN-AB angle, the Wits appraisal, the AF-BF distance, the APDI) were measured on pairs of prepubertal and postpubertal cephalograms of 44 normal occlusion subjects (20 males and 24 females). The mean ages at prepubertal and postpubertal stages were 10 years 5 months and 14 years 5 months in males and 8 years 10 months and 12 years 10 months in females, respectively. The purpose of this study was to compare prediction accuracy of future relationships by regression analysis and to evaluate interchangeability among the 7 parameters by correlation analysis. In the prepubertal assessment, the ANB angle and the angle of convexity showed better prediction accuracy for postpubertal jaw relationships. Higher interchangeability among the parameters was statistically substantiated between the SN-AB angle and the AF-BF distance, as well as among the ANB angle, the angle of convexity, and the A-B plane angle. The Wits appraisal and the APDI were less interchangeable with other parameters. The ANB angle, the Wits appraisal, and the APDI would complement each other for the geometrically distorting factors because of the low interchangeability due to their different geometric basis. The conjunctive use of the ANB angle, the Wits appraisal, and the APDI is recommended as a clinically appropriate method for assessment of jaw relationships in individuals.     

Effects of functional versus bisected occlusal planes on the Wits appraisal

Lateral cephalometric radiographs of 35 males between the ages of 11 years and 24 years, all of whom had Class II, Division 1 malocclusions, were traced and Wits appraisals were completed with the use of two occlusal planes: the functional occlusal plane and the bisected occlusal plane. These two values were then statistically related to two dental parameters (overjet and incisor angulation [1 to 1]) and one skeletal parameter (angle ANB) by means of the Pearson product-moment correlation with a predetermined level of statistical significance at p less than 0.05. The findings demonstrated that Wits values for both occlusal planes were significantly correlated to both skeletal and dental parameters. Each Wits value also shared variance with the Wits value for the other occlusal plane. Both Wits measures seem to vary to the same degree when compared to the other measures, as demonstrated by the r values. From the results of this experiment, three conclusions can be drawn: (1) either occlusal plane can be used in the calculation of the Wits appraisal to aid in the diagnosis of the severity or degree of anteroposterior jaw disharmony, (2) the bisected occlusal plane Wits appraisal value showed a higher relationship to dental measures than the functional occlusal plane Wits appraisal value, and (3) the functional occlusal plane Wits value shared slightly more variance with skeletal measures.     

ANB角与Wits值的关系

目的 揭示ANB角与Wits值的关系，探讨已知ANB能否准确预测Wits值，方法：研究选用100例（男女各50例）11－13岁Class I或Class II错He患者矫治前的头颅定位侧位片，患者均有较好骨生长型，I组：13例患者ANB小于等于1．5度，Wits值均为负：II组：61例5．8度大于ANB大于1．5度，Wits值或正或负；III组：26例ANB大于等于5．8度，Wits值均为正，借助计算机对各组进行统计分析。结果：分析发现无男女性别差异（P＞05），II组与III组ANB与Wits两值间有显著相关意义（P＜0．05），回归分析表明I组与II组有统计学意义（P＜0．05），我们在II组可以预测Wits值，准确率为21％，结论 ：尽管许多测量分析数据有统计学意义，但无显著的临床意义。     

Clinical application of a method to correct angle ANB for geometric effects

Angle ANB does not provide an adequate assessment of the skeletal discrepancy between the jaws in the sagittal plane. Attempts have been made to avoid the fallacies with the introduction of quadrilateral and Wits analyses. Based on the Wits appraisal of zero, Hussels and Nanda (1984) were able to evaluate and eliminate four geometric factors that affect angle ANB. These four factors are (1) anteroposterior position of point N in relation to points A and B, (2) inclination of the occlusal plane, (3) dental height (a linear measurement between point A and B), and (4) distance between points N and B. The authors derived a mathematic formula to evaluate the influence of all four parameters in terms of angle ANB. This formula reflects the skeletal relationship of a patient when points A and B are on a perpendicular plane in relation to the occlusal plane (Wits = 0 mm). The authors define this to be a Class I skeletal relationship. A comparison of the measured ANB angle with the calculated angle ANB gives a better perspective of the skeletal discrepancy. If the measured angle ANB is larger than the calculated angle, the discrepancy is Class II. On the other hand, if the measured angle ANB is smaller than the calculated angle, the skeletal relation is Class III. This method of assessing the skeletal sagittal position of the jaws in relation to each other was applied to 508 patients. The authors showed that the geometric influence of the four factors indeed conceals the true skeletal relations when angle ANB is used without any correction.(ABSTRACT TRUNCATED AT 250 WORDS)     

安氏Ⅱ类1分类错(牙合)上下颌基骨前后关系诊断指标的可靠性评价

目的评价反映安氏Ⅱ类1分类错（牙合）上下颌基骨前后关系13项指标的可靠性。方法安氏Ⅱ类1分类错（牙合）患者120例,男60例,女60例,年龄20-28岁。拍摄自然头位（NHP）下的头颅定位侧位片。一金属链悬于头颅前方,其在胶片上的影像作为确定真性水平面（THP）的依据。X线头影测量项目包括ANB角、AB平面角、Wits值、AF—BF、AXB平面角、AB／SN4、AB／PP、AXD平面角、AD／SN、SGrdAB角、APDI角、FABA角、B角及A、B两点在THP上垂足间的距离（AB／HP）。计算各测量项目的相关系数：测量结果按最小相关系数指标分类法行聚类分析。所有测量结果用SPSS11．0统计软件进行分析。结果相关分析表明各项指标除Wits值和SGrdAB角外多数呈高度相关性：聚类分析采用最小相关系数指标分类,结果按0．60水准分为5类。结论在安氏Ⅱ类1分类错（牙合）患者中,除Wits和SG11／AB外其他11项指标均可作为上下颌基骨前后关系的评价指标。AB／SN。能比较真实地反映上下颌骨的矢状关系：ANB角、AB平面角、β角、AF—BF、AXB平面角、FABA角、AB／PP、APDI角等指标具有相似的临床意义。     

153例错畸形患者W角的测量分析研究

目的:本研究使用一种新的头影测量方法-W角评价上下颌骨矢状向关系,据此分析安氏3种错类型W值。方法:对153例11～20岁患者头颅侧位片进行头影测量分析,按照ANB角、Wits值和β角分为3组,取平均值和标准差,分析男女差异。结果:分析安氏3种错类型患者W角的正常值;3组W值间差异有统计学意义(P<0.05);各组W值在性别上没有显著差异。结论:W角能反映上下颌骨矢状方向不调,具有较好可重复性。