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。     

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。     

安氏Ⅱ类1分类错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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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、SGn/AB角、APDI角、FABA角、β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SGn/AB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患者中，除Wits和SGn/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/SN4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。     

Age-related changes in sagittal relationship between the maxilla and mandible

The aim of the study was to assess age-related changes in sagittal jaw relationship during pre-pubertal and pubertal development on the basis of angular [ANB, anteroposterior dysplasia indicator (APDI) and A-B plane angle] and linear (Wits, AF-BF, App-Bpp, and App-Pgpp) measurements. Lateral cephalograms of orthodontically untreated subjects were evaluated at 7, 9, 11, 13 and 15 years of age. Cephalometric standards and age-related changes were determined on the basis of Class I subjects with a good occlusion (n = 18, 10 males and 8 females). With respect to changes related to growth, the main findings were, in both genders, a statistically significant age-related decrease in ANB angle, App-Bpp and App-Pgpp, a significant increase in APDI, but no age-related change in Wits. A reduction of sagittal jaw distance during pre-pubertal and pubertal development was observed arising from a relative dominance of sagittal mandibular growth. For an evaluation of differences concerning jaw relationship in Class II subjects, a group with Class II division 1 malocclusions (n = 17) and a group with Class II division 2 malocclusions (n = 12 were compared with two control groups, i.e. the good occlusion group and a Class I group (n = 37). Conclusions about the sagittal discrepancy in Class II division 1 and Class II division 2 subjects depended on the geometric reference used in the various parameters, and further research is called for with respect to the diagnostic performance of the various measurements. Differences between Class II subjects and controls present at 15 years of age were already established at 7 years of age, but were less pronounced.     

A comparison of ANB, WITS, AF-BF, and APDI measurements

In the present study, the relationships among ANB, Wits, AF-BF, and APDI measurements used in the assessment of the anteroposterior jaw disorders were examined on the cephalometric radiographs of 63 male and 82 female subjects, and high correlations were found among them. Furthermore, relationships were explored between these parameters and some measurements that were thought to have influenced them. The results of the geometric studies could not be proved on the basis of statistical evaluation.     

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.     

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。     

Overjet as a predictor of sagittal skeletal relationships

Skeletal relationships in the sagittal plane do not always correspond with dental relationships. The aim of this study was to determine in which type of malocclusion the correlation between overjet and skeletal sagittal parameters assessed by lateral cephalogram analysis is the highest. The extent to which overjet can predict skeletal relationships in the sagittal plane was also assessed. Eighty-three subjects fulfilled the inclusion criteria (40 males and 43 females, mean age 16.3 +/- 4.3 years). Overjet was measured on study casts and sagittal skeletal relationships were analysed on lateral cephalograms. ANB angle, Wits appraisal, and convexity at point A were determined. Mean values and standard deviations of measured parameters were calculated for Class I, Class II division 1, and Class III malocclusion subjects. Correlation between overjet measured on study casts and sagittal skeletal parameters measured on lateral cephalogram was calculated. Overjet as a predictor of skeletal relationships was assessed by means of linear regression analysis. A statistically significant positive correlation (P < 0.01) was found between the values of overjet and ANB (r = 0.690), overjet and Wits appraisal (r = 0.750), and overjet and convexity at point A (r = 0.608) when assessing the whole sample. When linear regression between overjet and cephalometric parameters was assessed separately in Class I, Class II division 1, and Class III malocclusion subjects, the percentage of variability was statistically significant in just four pairs. The findings show that overjet is a good predictor of sagittal relationship only in subjects with a Class II division 1 malocclusion.     

颅底重叠法Wits值的评价

目的 探讨颅底重叠法测量Ｅｉｔｓ值与常规Ｗｔｉｓ值测量法对评价治疗前后颌骨矢状关系改变的可靠性。方法 样本为４８例经过正畸治疗的错卧倒患者的头颅侧位片，用计算机数字化仪测量法分别测量常规Ｗｉｔｓ值、颅底重叠法Ｗｉｔｓ值及ＡＮＢ角在治疗前后的变化，用ＳＡＳ软件包对３者间的相关笥进行统计分析。结果 重叠法Ｗｉｔｓ值与ＡＮＢ角之间的相关笥明显高于常规Ｗｉｔｓ值，相关系数高达０．８４９，差异具有高度显著性     

Anteroposterior dysplasia indicator: an adjunct to cephalometric differential diagnosis.

1. Cephalograms of 102 children with normal occlusion (Group 1) and 874 children with various malocclusions were analyzed to determine which measurements would produce the highest correlation against the displacement of the molar relationships. 2. Molar displacement was measured directly on the study casts, and an average of the measurements of the right and the left sides was obtained. 3. The malocclusion sample was divided into groups according to molar displacement: 214 neutroclusion cases (Group 2), 624 distoclusion cases (Group 3), and 36 mesioclusion cases (Group 4). 4. The mean value of the anteroposterior dysplasia indicator (APDI) in the normal group was 81.4 degrees, with a standard deviation of 3.79. 5. The APDI reading was obtained by tabulating the facial angle plus or minus the A-B plane angle and plus or minus the palatal plane angle. 6. Among the measurements tested, the APDI was found to show the highest correlation against the molar displacement, with a correlation value of 0.643. 7. The four variable that produced the highest correlation coefficient value--that is, the ANB angle (-0.495), the A-B pland angle (0.566), the "Wits" appraisal (-0.639), and the APDI (0.643)--were subjected to a study of their frequency distribution patterns. High percentage of overlapping of the two extreme groups (distoclusion and mesioclusion groups) were found in the above variables, with the exception of the APDI. 8. A discussion of the differential diagnostic value of the APDI was presented, together with illustrations and various clinical examples.     

前磨牙正锁对下颌骨矢状向位置的影响

目的 研究前磨牙正锁对青少年下颌骨矢状向位置的影响,为正确诊断和掌握正畸治疗时机及制定合理临床治疗方案提供参考。方法 选择2004—2017年间就诊于中国医科大学附属口腔医院正畸科的前磨牙正锁青少年患者100例为研究对象,其中男54例、女46例,单侧前磨牙正锁70例、双侧前磨牙正锁30例。选用其正畸治疗前的X线头颅侧位片,利用Winceph 9.0软件测量16项上、下颌骨矢状向相关硬组织指标,采用SPSS 21.0软件包将所得测量数据与正常标准值进行比较。结果 研究组区分单侧前磨牙正锁与双侧前磨牙正锁,与正常值相比,Beta角、SNB、SND、ANB、AB平面角、APDI、颌凸角、面角、Wits值、S-Co、Co-Po的差异均有统计学意义（P<0.05）。相比于正常值,单侧前磨牙正锁组Go-Pog差异亦有统计学意义（P<0.05）。结论 青少年前磨牙正锁患者,矢状向上颌骨位置正常,下颌骨位置后退,有形成骨性Ⅱ类面型的趋势。前磨牙正锁影响下颌骨发育,导致下颌体、下颌骨长度偏小。提示正畸诊治过程中,应提高对青少年前磨牙正锁的关注,及早进行正畸治疗,预防对下颌骨发育及矢状骨面型造成的不利影响。     

儿童和成人深覆牙合牙合颅颌形态的横断面研究

目的对儿童和成人深覆牙合患者的颅颌面形态进行横断面研究,分析其生长发育中颅颌形态变化的趋势,探讨成人深覆牙合患者的颅颌面形态特征。方法随机抽取Ⅲ度儿童深覆牙合患者159例（平均年龄12.47岁）,成人深覆牙合患者81例（平均年龄21.76岁）,个别正常对照组51例（平均年龄18.41岁）。采用Winceph 7.0软件对3组X线头影测量项目进行测量,采用SPSS 12.0软件进行统计学分析。结果儿童深覆牙合患者在上前面高、下前面高、上颌第一磨牙相对于上颌前部的位置、上颌骨长度、上下颌骨-平面距、上颌磨牙-腭平面距、下颌切牙-下颌平面距、上下齿槽座点平面-下颌平面角、下颌角、下颌切牙距、覆盖、下颌平面-前颅底平面角、下颌磨牙-下颌平面距、后面高、上颌切牙距、下颌体长度、下颌升支高度、平面-前颅底平面角、上颌中切牙-前颅底平面角与成人深覆牙合患者间差异有统计学意义。成人深覆牙合患者在下颌-前颅底平面角、上下颌骨-前颅底平面角、颌凸角、上下颌骨矢状向不调指数、上下颌骨垂直向不调指数、上下颌骨-平面距、上下齿槽座点平面-下颌平面角、下颌角、覆盖、下颌平面-前颅底平面角、上颌后部位置、下颌磨牙-下颌平面距、上颌中切牙-前颅底平面角、下颌体长度、下颌升支高度、后颅底长度、平面-前颅底平面角、后面高与正常个体间差异有统计学意义。结论深覆牙合患者随着年龄的增长,颅、颌、、面部仍表现有一定的生长潜力,但是患者颌骨矢状关系并无改善。成人深覆牙合患者颌面部特征表现为垂直向、矢状向关系显著不调。     

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.     

The use of linear and angular measurements of maxillo-mandibular anteroposterior discrepancies

A new reference plane where the anteroposterior discrepancy between maxilla and mandible could be measured, namely the bisector of the palatal plane to mandibular plane angle, has recently been proposed. The aims of the present investigation were to extend the assessment of the clinical significance of this measurement to a large group of randomly selected patients of both sexes, and to verify the correlation of this measurement to well-established angular and linear assessments of anteroposterior discrepancy. On the pretreatment lateral cephalograms of 306 orthodontic patients (165 males, 141 females) aged between 6 and 50 years, the following measurements were obtained: ANB angle; corrected ANB* angle (computed as: ANB* = original ANB angle + 0.5 × (81.5°-SNA angle) + 0.25 × (32°-SN-GoMe angle), which compensates for the position of the maxilla and rotation of the mandible relative to the cranial base; Wits appraisal; MM-Wits: linear distance between the projections of A and B points on the bisector of the palatal plane to mandibular plane angle. The MM-Wits distance was significantly correlated to two angles (ANB and ANB*), as well as with the Wits appraisal. All the correlations performed did not show sex- or age-characteristic patterns. The correlation to the corrected ANB* was the best among the three, with a correlation coefficient of 0.915, MM-Wits (mm) = 1.497 × ANB* (degrees) ?6.784. From the correlation, reference values for the new measurement have also been estimated, and found to be between ?0.65 and ?6.85 mm for skeletal Class I individuals. Nevertheless, it is recommended that the diagnosis of orthodontic anomalies should be performed taking into consideration more than a single anteroposterior appraisal.     

The use of linear and angular measurements of maxillo-mandibular anteroposterior discrepancies.

OBJECTIVES: To extend the assessment of the clinical significance of the measurement of the anteroposterior discrepancy between maxilla and mandible on the bisector of the palatal plane to mandibular plane angle to a large group of randomly selected patients of both sexes, and to verify the correlation of this measurement to well established angular and linear assessments of anteroposterior discrepancy. DESIGN: Retrospective analysis of pre-treatment lateral cephalometric radiographs. SETTING AND SAMPLE POPULATION: The Laboratory of Functional Anatomy of the Stomatognathic Apparatus at Milan University, Italy. Three hundred and six orthodontic patients (165 males, 141 females) aged between 6 and 50 years. EXPERIMENTAL VARIABLE: ANB angle; corrected ANB* angle which compensates for the position of the maxilla and rotation of the mandible relative to the cranial base; Wits appraisal; MM-Wits: linear distance between the projections of A and B points on the bisector of the palatal plane to mandibular plane angle. RESULTS: The MM-Wits distance was significantly correlated to two angles (ANB and ANB*), as well as to the Wits appraisal. All the correlations performed did not show sex- or age-characteristic patterns. The correlation to the corrected ANB* was the best among the three, with a correlation coefficient of 0.915, MM-Wits (mm) = 1.497 x ANB* (degrees) -6.784. From the correlation, reference values for the new measurement have also been estimated, and found to be between -0.65 and -6.85 mm for skeletal Class I individuals. CONCLUSION: It is recommended that the diagnosis of orthodontic anomalies should be performed taking into consideration more than a single anteroposterior appraisal.     

Relation of the Wits appraisal to the ANB angle: a statistical appraisal

The hypothesis that the relationship between the ANB angle and the Wits appraisal can be expressed by measuring the individual variations in their reference systems and by constructing a model of regression between them and a few parameters describing the reference systems was tested with material consisting of 30 lateral cephalometric radiographs of untreated orthodontic patients with different types of skeletal and/or dentoalveolar malocclusions. The results indicated that approximately 93% of the variation of the Wits appraisal could be explained by the variation of the ANB, NSL/OL, and SNA angles. The study also showed that the results given by different measurements with different reference systems, such as the ANB angle and the Wits appraisal, cannot be directly compared. To obtain comparable interpretations, one should correct the results of both measurements in relation to the variations in their reference systems.     

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。     

Application of the "Wits" appraisal.

The "Wits" appraisal is intended as a diagnostic aid to be used in conjunction with other analyses. Whereas the popularly used ANB angular reading is a simple method of measuring degree of jaw disharmony, there are many instances in which this reading is suspect. The "Wits" appraisal permits easy identification of these shortcomings and substitutes a reasonably reliable means of measuring extent of anteroposterior jaw disharmony.     

A new index for evaluating horizontal skeletal discrepancies and predicting treatment outcomes

The cephalometric measurement known as Wits appraisal (AOBO) was studied to determine its importance in diagnosis, treatment, and prediction of treatment success. The Wits appraisal is used primarily to identify unreliable ANB values (those that do not accurately reflect the degree of horizontal jaw discrepancy, ie, those that differ greatly from the AOBO value). Therefore, differences between AOBO and ANB also were evaluated. Because neither measurement alone can assess jaw discrepancies with total accuracy, they were combined, plotted on a scattergram, and divided into equal zones to create a new index of horizontal skeletal discrepancies and treatment predictability. Pretreatment values correspond to treatment difficulty, and posttreatment values correspond to the effectiveness of treatment. Treatment time for each zone also was evaluated. We were able to draw several conclusions from this study. First, combining AOBO and ANB values results in a more accurate measurement of treatment difficulty. These combined values also can be used to predict both treatment time and the success of treatment for horizontal discrepancies. Second, the AOBO value predicts variations in treatment time at each ANB value. Finally, adding ANB and AOBO values and then dividing the total yields zones that represent statistically significant differences in treatment times and percentages of success. The zones also correlate with the difference between AOBO and ANB measurements.