Selection of criteria for assessment of occlusal acceptability

There is no general agreement on criteria that could be applied to distinguish between orthodontically acceptable and non-acceptable occlusions after the completion of dental development. The aim of the present study was to analyse morphological and functional features that could be used as an index to define an acceptable occlusion in young adults. Three expert panels representing specialists in orthodontics and stomatognathic physiology participated in a modified Delphi method. Each panel responded to a questionnaire concerning the usefulness of various occlusal features, and a set of characteristics was selected on the basis of the responses; thereafter, applicability of the chosen characteristics and their cut-offs for an acceptable non-acceptable dichotomy was tested clinically. To obtain a consensus level of 100%, the last panel session was completed with a group discussion. Assessments made using the morphological criteria were compared with those made with the dental health component of the Index of Orthodontic Treatment Need. The selected morphological characteristics consisted of overjet, overbite, canine relationship, crossbite, scissors bite and midline deviation. The functional evaluation comprised assessments of discrepancy between the centric relation and the intercuspal position, working- and non-working-side contacts and protrusion contacts. The dental health component and our morphological criteria showed different sensitivity to contact point displacements, interdigitation in buccal segments and increased overbite. This study provides a set of morphological and functional indicators reflecting the current consensus opinion of Finnish professionals. Further studies are needed to analyse the reproducibility of assessment of the characteristics included.     

应用 PAR 指数评价80例患者正畸治疗效果的影响因素分析

目的：探讨 PAR 指数评价正畸治疗的患者临床疗效的影响因素。方法：采集80例患者的一般信息、诊治信息、调查问卷以及模型测量等数据,应用 PAR 指数进行分析。结果：42．5％患者改善,56．3％患者极大改善。不同性别、分类、是否拔牙之间,治疗后 PAR 以及 PAR 减少率无显著差异,不同安氏分类之间,治疗前 PAR 和治疗后 PAR 减少量有显著差异。治疗前 PAR 分别与 PAR 减少量及减少率存在线性回归关系。治疗后安氏Ⅲ类患者 PAR 减少量最明显,Ⅱ类次之,Ⅰ类较低。结论：性别、分类、是否拔牙对 PAR 所反映的改善程度的影响不显著。不同安氏分类下 PAR 所反映的错(牙合)畸形较重的患者改善程度较明显。     

Technique Comparison for Efficient Orthodontic Tooth Measurements Using Digital Models

Objective:To determine the best technique for measuring mesial-distal tooth widths on digital models.Methods:The individual mesial-distal tooth widths were measured (first molar to first molar, maxillary and mandibular) on 32 stone casts and corresponding digital models (emodels, GeoDigm, Chanhassen, Minn). The digital models were measured using five different techniques: occlusal aspect, occlusal aspect zooming in on each individual tooth, facial aspect rotating as needed, facial aspect from three standard positions (R buccal, facial, and L buccal), and qualitatively rotating the model in any position deemed necessary. Measurements were repeated three times at least 1 week apart. The operator time needed to complete each set of measurements was recorded.Results:Four of five digital measurement techniques (except for the facial aspect from three standard positions) showed a slight positive bias (overestimation in measured width) compared with stone cast measurements. Measuring from the occlusal aspect resulted in the greatest Pearson correlation (98.509%), the least Altman-Bland standard deviation of differences value (1.881 mm), and the second fastest measuring time (2 minutes 3 seconds). Qualitatively rotating the model had similar Pearson correlation and Altman-Bland values to the Occlusal technique but took the longest time to measure (7 minutes 1 second).Conclusions:The Occlusal measurement technique for digital models was the best combination of accuracy, repeatability, and speed of measurement.     

Objective treatment outcome assessment of a completely customized lingual appliance: A retrospective study

ObjectiveTo assess the outcome quality of subjects treated with a completely customized lingual appliance (CCLA) in a postgraduate university program, using the ABO Objective Grading System (OGS), by testing the null-hypothesis of a significant proportion of post-treatment cases exceeding an adjusted ‘exam failure’ threshold value of OGS = 24.Materials and MethodsThis retrospective single-arm study included 66 consecutively debonded CCLA cases (m/f 19/47; mean age: 25.1 ± 9 years) treated at Hannover Medical School (MHH, Hannover, Germany). The discrepancy index (DI) was assessed on initial plaster casts. The OGS of the cast-radiograph evaluation was scored for both set-up and post-treatment casts, including the seven components of alignment/rotation, marginal ridges, buccolingual inclination, overjet, occlusal contacts, occlusal relationships and interproximal contacts, to parameterize differences between those.ResultsDI score distribution (≥ 20, < 20) was 25 (37.9%)/41 (62.1%) subjects. Mean initial DI was 17.3 ± 8.5. Mean set-up OGS was 10.4 ± 4.4 (min-max: 3–21), mean final OGS was 17.7 ± 5.9 (min-max: 7–33), and the difference 7.3 (post-treatment - set-up) was statistically significant (p < 0.0001; 95% CI [5.8, 8.7]). The null-hypothesis was rejected: A statistically significant proportion of the final casts (n = 58; 87.8%) scored below OGS = 24 by exact binomial test (P < 0.0001; 95% CI [77.5%, 94.6%]). The rate of a final OGS score < 24 was not significantly different (P = 0.98) between both DI (≥ 20, < 20) groups.ConclusionsThe outcome quality of the CCLA treatment in this postgraduate university setting was high and therefore sufficient for a vast majority of treated cases to pass the ABO-OGS clinical examination.     

正常牙合模型近景立体摄影测量研究（二）——牙齿及牙列指数的测量分析

通过对６０例正常少年牙颌模型的测量计算，建立了正常少年有关牙颌模型指数的正常值，并对Ｐｏｎｔ指数和Ｂｏｌｔｏｎ指数进行了分析，认为Ｐｏｎｔ指数在正畸临床有一定的实用价值，但不能机械套用；Ｂｌｏｔｏｎ指数虽有较大的临床意义，但也存在一定的局限性     

基于在线问卷的口腔正畸学形成性评价作业文档归集系统：研发与应用

目的探讨易于部署的形成性评价作业文档归集系统的研发方法,并评估口腔正畸学教师对其接受程度。 方法基于在线问卷系统,利用Python语言开发问卷数据转换程序,优化形成性评价中作业电子文档的归集流程。对佛山科学技术学院附属口腔医院正畸学教研室教师开展培训,分别记录使用电子邮件系统、在线问卷系统和本归集系统收集10份作业文档的操作时间与点击次数,使用方差分析进行相互比较。同时发放问卷对接受培训教师既往使用在线问卷的情况进行调查,利用单因素及多因素回归调查各方法操作时间的影响因素。 结果本研究自2019年5月至2019年7月由佛山科学技术学院附属口腔医院正畸学教研室教师中按照便利抽样方式招募20位高校教师,其中男11人、女9人,年龄（37.8 ± 7.3）岁,均为口腔医学专业。全部教师参与培训并认真填写了问卷。在统一进行培训后,教师通过电子邮件[用时（10.40 ± 2.43）min,点击次数151.0 ± 70.6]、在线电子问卷[用时（5.91 ± 0.13）min,点击次数37.7 ± 10.5]与本系统[用时（3.99 ± 0.34）min,点击次数11.0 ± 1.7]进行10份作业文档的归集工作,单因素方差分析提示不同归集方法的平均时间差异具有统计学意义（F = 106.7,P<0.001）,不同方法间点击次数差异也具有统计学意义（F = 64.9,P<0.001）。多重线性回归结果提示,既往收集电子文档的频次是本系统使用时间的独立预测因素（回归系数-0.34,P = 0.04）。 结论利用本系统收集电子作业文档操作更为简捷,效率也明显高于传统手段,近期进行过电子文档收集工作的教师更容易掌握本系统的使用。整体而言,接受培训的教师愿意将其应用于今后的教学工作中,改善口腔正畸学教学中形成性评价的工作流程。     

Bio-psycho-social assessment of occlusal dysaesthesia patients

Dentists occasionally experience occlusal dysaesthesia (OD) patients, who complain of bite discomfort without evident occlusal abnormalities. It is suggested that this condition is related to somatosensory abnormalities of the trigeminal system and/or psychological problems such as somatoform disorders. The aim of this study was to investigate the characteristics of OD with a bio-psycho-social approach. Twelve OD patients (10 women, two men; mean age 54.7 years) and twelve healthy volunteers (10 women, two men; mean age 54.8 years) were selected. They were assessed using (i) interdental thickness discrimination ability test using 2-, 5- and 10-mm-thick standard blocks and 12 test blocks that were thinner or thicker than the corresponding standard block and (ii) psychological tests: General Health Questionnaire (GHQ60) and Profile of Mood States (POMS) brief-form. There was no significant difference in the interdental thickness discrimination ability between OD patients and controls (mixed-model anova, P=1.000). Regarding psychological tests, there were no significant differences between OD patients and controls in the total scores for either GHQ60 (P=0.143) or POMS brief-form (P=0.319) (Wilcoxon's test). However, OD patients showed significant differences from controls in several subscales, that is, 'somatic symptoms' (P=0.039) and 'severe depression' (P=0.039) for GHQ60 and 'depression-dejection' (P=0.014) and 'vigour' (P=0.008) for POMS brief-form (Wilcoxon's test). These results suggest there is no difference in interdental thickness discrimination ability between OD patients and normal controls, but OD patients tend to score higher on psychosomatic distress.     

咬合感觉障碍的病因、诊断标准及治疗进展

目前,咬合感觉障碍(occlusal dysesthesia,OD)被认为是躯体形式障碍的一种衍生形式,其症状主要表现在口腔区域,多为原因不明的咬合不适感,而曾经进行过的牙科治疗可能触发该症状.为了尽早地在临床实践中对此类患者进行诊断和治疗,本文将围绕咬合感觉障碍这一疾病从流行病学、病因学、诊断标准、治疗、预后等五个方...     

Performance of electrical resistance measurements adjunct to visual inspection in the early diagnosis of occlusal caries

The detection of small carious lesions at occlusal surfaces is a difficult task, particularly in low caries prevalence populations and individuals. The aim of this study was to evaluate the performance of electrical resistance measurements (ERM) in diagnosing small dentinal lesions at one site per occlusal surface in low caries prevalence populations when used adjunct to visual inspection, and to compare the performance of ERM to that of radiographic examination. The occlusal surfaces of 81 third permanent molar teeth extracted from young adolescents were diagnosed by four examiners, who measured the electrical resistance of enamel on a one measurement per surface basis, and furthermore assessed the occlusal surfaces visually and radiographically. The teeth were sectioned for validation by histological examination. The ERM had the highest sensitivity (0.67), and visual inspection had the highest specificity (0.89). ROC analysis showed no statistically significant differences between the performance of the observers when using visual inspection and ERM (z-score test; P > 0.05). One examiner performed statistically significantly better by measuring the electrical resistance of enamel than by radiographic examination (P < 0.05). The average sensitivity and specificity of the three diagnostic systems were used to express the positive and negative predictive values as a function of caries prevalence. At a caries prevalence of 0.2 the negative predictive values for visual inspection, ERM and radiographic examination were 0.88, 0.91 and 0.89, and the positive predictive values were 0.53, 0.48 and 0.42 respectively. It was concluded from the very low positive predictive values that neither ERM used in this way nor radiography aid visual inspection in detecting small occlusal caries lesions, when applied in low caries prevalence populations or individuals.     

A modified technique for the intraoral assessment of static occlusal contacts

This article describes a procedure in which articulating paper is modified for the intraoral assessment of static occlusal contacts. The rectangular-shaped articulating paper is modified by creating parallel cuts at 2- to 3-mm intervals perpendicular to its long side without completely separating the paper. This modification may improve the accuracy in determining occlusal contacts and therefore facilitate an occlusal adjustment procedure.     

Developing an acceptability assessment of preventive dental treatments

Objectives: Early childhood caries (ECC) is very prevalent among young Hispanic children. ECC is amenable to a variety of preventive procedures, yet many Hispanic families underutilize dental services. Acceptability research may assist in health care planning and resource allocation by identifying patient preferences among efficacious treatments with the goal of improving their utilization. The purposes of this study were (a) to develop a culturally competent acceptability assessment instrument, directed toward the caregivers of young Hispanic children, for five preventive dental treatments for ECC and (b) to test the instrument's reliability and validity. Methods: An instrument of five standard treatments known to prevent ECC was developed, translated, reviewed by focus groups, and pilot tested, then tested for reliability. The instrument included illustrated cards, brief video clips, and samples of the treatments and was culturally appropriate for low-income Hispanic caregivers. In addition to determining the acceptability of the five treatments individually, the treatments were also presented as paired comparisons. Results: Focus groups and debriefing interviews following the pilot tests established that the instrument has good face validity. The illustrated cards, product samples, and video demonstrations of the five treatments resulted in an instrument possessing good content validity. The instrument has good to excellent test–retest reliability, with identical time 1–time 2 responses for each of the five treatments 92 percent of the time (range 87 to 97 percent), and the same treatment of the paired comparisons preferred 75 percent of the time (range 61 to 90 percent). Conclusions: The acceptability instrument described is reliable and valid and may be useful in program planning efforts to identify and increase the utilization of preferred ECC preventive treatments for target populations.     

A test for occlusal function. The value of a masticatory efficiency test in the assessment of occlusal function

A sample consisting of 50 adult subjects aged between 21-23 years was assessed for their masticatory ability, by the use of a masticatory efficiency test. The occlusal status was assessed from study models using five occlusal indices. The scores obtained from the masticatory efficiency tests were correlated to those obtained from the occlusal analyses, using a correlation coefficient test. Significant correlations were found between the two scores. A multiple regression analysis was used to predict the masticatory efficiency from the occlusal scores. The findings revealed that only a small proportion of the masticatory efficiency could be predicted. This suggested that factors other than those used in these indices may have an effect on the masticatory efficiency.     

Relationship between pretreatment case complexity and orthodontic clinical outcomes determined by the American Board of Orthodontics criteria

Objective:To evaluate the relationship between pretreatment case complexity and orthodontic treatment outcomes.Materials and Methods:The total sample contained 1693 cases (853 females and 840 males, mean age  =  16.3 years) from the archives of postgraduate orthodontic clinics. The complexity of each case was evaluated using the American Board of Orthodontics (ABO) Discrepancy Index (DI), and orthodontic clinical outcomes were evaluated using the ABO Objective Grading System (OGS). Only one investigator evaluated all cases. Multivariate analysis of variance, correlation analysis, and multiple variable regression analysis were used for statistical evaluation (P < .05 as significant).Results:The mean total DI score was 16.2, and the mean total OGS score was 18. No significant correlation was found between the total DI and the total OGS scores. However, pretreatment overbite, lateral open bite, crowding, buccal posterior crossbite, and other components affected the total OGS score significantly. The highest percentage of passing OGS values was found for cases of medium-level complexity.Conclusion:This retrospective study of university clinical records showed that the posttreatment clinical outcomes were significantly affected from pretreatment case complexity. Posttreatment alignment was affected significantly from pretreatment buccal posterior crossbite and cephalometric values. Similarly, posttreatment buccolingual inclination was affected from pretreatment anterior open bite, occlusion, and other factors. Occlusal contacts were affected significantly from pretreatment lingual posterior crossbite and other factors. In addition, we determined that posttreatment root angulations were affected significantly from pretreatment crowding values.     

Changes in the occlusal function of orthognathic patients with vertical malformations after combined orthodontic surgical therapy: a prospective clinical study

The aim of this study was to assess the changes in occlusal patterns during combined surgical and orthodontic therapy in patients with vertical jaw malformations. Twenty-six orthognathic patients (18 female, eight male; median age 25 years, interquartile range 11.5 years) and 10 control patients (five female, five male; median age 29.8 years, interquartile range 13.5 years) recruited from neutral configured patients attending the Department of Orthodontics, were investigated. Based on cephalometry, the patients were grouped into vertical skeletal configurations of either open, deep, or natural bite cases. Registrations of the occlusal contacts were taken using a digital occlusal sensor immediately before surgery and at 9 months after the surgical intervention. Before the intervention, open and deep bite patients showed significantly less efficient occlusal patterns than the untreated controls regarding total tooth contact (P < 0.001), time of occlusion (P = 0.002), occlusal asymmetry (P = 0.001), anterior tooth contact (P < 0.001), and posterior tooth contact (P < 0.001). After surgery, the parameters in the deep bite patients were similar to those in the controls; however, in open bite patients, total tooth contact (P = 0.003), occlusal asymmetry (P = 0.011), and posterior tooth contact (P = 0.035) differed significantly. In conclusion, combined orthodontic and surgical correction of vertical malocclusions was found to improve occlusal function in patients with deep bite to the level of controls.     

数字化效果模拟器在口腔正畸临床教学中的应用效果评估

目的评估数字化效果模拟器在口腔正畸临床教学中的应用效果。 方法选取2020—2021年于中山大学附属口腔医院正畸科就诊的安氏Ⅰ类、安氏Ⅱ类和安氏Ⅲ类错畸形病例共6个，完善问诊、临床检查和X线片检查后，提供相应的石膏模型和数字化模型。中山大学光华口腔医学院口腔正畸学专业的2018 ~ 2021级研究生28人通过分层随机抽样法分为两组（每组14人），分别进行传统的石膏模型排牙预测（A组）和数字化效果模拟器预测（B组），并完成正畸诊断和治疗计划。由具有硕士生导师资格的3位教师对其诊断和治疗计划进行评估，同时讲授其依据。两组学生分别对传统石膏排牙预测和数字化效果模拟器预测过程进行评价。 结果在"制定方案主动性"和"考虑牙移动细节"方面，B组学生得分高于A组，差异具有统计学意义（P<0.001）。相比于A组，B组中更多学生认为数字化模拟器可提高学习兴趣（A组78.57%、B组100%）、加深对诊断与治疗计划的理解（A组75.00%、B组89.28%）和考虑更多三维牙移动（A组64.28%、B组75.00%）。在教师评价中，B组在治疗计划讲授过程得分高于A组（P<0.001）。 结论数字化效果模拟器可锻炼学生的临床思维能力，提高口腔正畸诊断与治疗计划的制定的教学效果。     

改良迷你临床演练方法在口腔正畸科考核中的初步应用

目的探讨将Tweed分析法与迷你临床演练（Mini-CEX）相结合,建立适用于口腔正畸专科的临床考核方案的效果。 方法通过将Mini-CEX方法与正畸学Tweed分析表进行结合,并补充细化评分表,从而建立了一种新型口腔正畸学教学考核方法,称为改良Mini-CEX考核。于2019年9月,从上海交通大学医学院附属第九人民医院口腔正畸科随机选取6名在培口腔专科培训医师作为考生,对考生进行改良Mini-CEX考核,由5名正畸专家对其表现进行打分。应用SPSS 21.0软件对打分结果进行统计,计算肯德尔和谐系数（W）并进行显著性检验。 结果不同考官在评价同一考生时,考官间的打分具有显著的一致性（W₁ = 0.742,P₁ = 0.001;W₂ = 0.666,P₂ = 0.003;W₃ = 0.720,P₃ = 0.001;W₄ = 0.628,P₄ = 0.004;W₅ = 0.555,P₅ = 0.011;W₆ = 0.330,P₆ = 0.1293）。在医疗面谈、体格检查、临床判断、卫生教育、组织效能和整体表现6项,打分具有显著的一致性（W₁ = 0.620,P₁ = 0.008;W₂ = 0.588,P₂ = 0.012;W₃ = 0.885,P₃<0.001;W₄ = 0.625,P₄ = 0.008;W₅ = 0.835,P₅ = 0.001;W₆ = 0.930,P₆<0.001）,仅人文关怀一项未通过一致性检验（W = 0.147,P = 0.598）。 结论改良Mini-CEX具有标准程序,建立明确的得分细节,可以考核全面、获得公正客观,在不同考官间具有良好一致性,适用于当前口腔正畸学的考核与评价。