Influence of lateral cephalometric radiography in orthodontic diagnosis and treatment planning

Objective:To evaluate the impact of additional lateral cephalometric radiography in orthodontic diagnosis and treatment planning.Materials and Methods:Forty-three patients seeking orthodontic treatment, and for whom pretreatment diagnostic records were available, were randomly selected. Ten qualified orthodontists were involved in this study. The patients'' records included three photographs of the angle trimmed dental casts, digital lateral cephalometric and panoramic radiographs, and standard clinical photographs comprising seven intra- and four extraoral pictures. Records were evaluated in two sessions. At the first session, orthodontists evaluated records without lateral cephalometric radiography (LCR). In the second session, the same information was presented, but with LCR. Between the two sessions the order in which the cases were presented was altered to avoid bias.Results:The percentage of agreement between sessions was lower for diagnosis than for treatment planning. Concerning skeletal classification, the least experienced orthodontist was the least consistent (28%), while the more experienced orthodontist was the more reliable (67%). In terms of treatment modalities, in general there was an agreement of 64%. The most frequent modifications in treatment modalities were seen in Class II malocclusion patients.Conclusions:The results of our study suggest that the majority of Portuguese orthodontists judge that LCR is important to producing a treatment plan. Despite that, it does not seem to have an influence on orthodontic treatment planning.     

Contribution of pretreatment radiographs to orthodontists' decision making

A study was conducted to determine the amount of diagnostic and treatment planning information gained by orthodontists when pretreatment radiographs are added to a set of orthodontic records. Thirty-nine orthodontists evaluated six test cases and formulated a diagnosis and treatment plan. Information was collected about the participants' certainty with their diagnoses and treatment plans, the impact of the radiographs, the number and type of radiographs that were selected, and the difficulty of each case. Results showed that orthodontists were approximately 75% confident of their diagnosis before reviewing any radiograph. There were 741 radiographs ordered, of which 192 produced changes to the diagnostic process. The lateral cephalometric radiograph was the most productive. Panoramic and full-mouth series were productive but provided largely duplicative information.     

Consistency of orthodontic treatment decisions relative to diagnostic records

The purpose of this study was to evaluate how incremental information obtained from different types of diagnostic records contributes to the determination of orthodontic treatment decisions. Pretreatment records of 57 orthodontic patients were assessed by five orthodontists who were part-time faculty members and also in private practice. This sample consisted of dental school orthodontic patients who had Class II malocclusions and included patients at three different dental developmental stages. The following diagnostic records were used: study models (S), facial photographs (F), a panoramic radiograph (P), a lateral cephalogram (C), and its tracing (T). Five combinations of diagnostic records were presented to the orthodontists in the following sequence: (1) S; (2) S + F; (3) S + F + P; (4) S + F + P + C; and (5) S + F + P + C + T. The simultaneous interpretation of all diagnostic records (S + F + P + C + T) was used as the "diagnostic standard." There was a diagnostic standard for each of the patients and for each of the orthodontists. The diagnostic standard was achieved: (1) S = 54.9%, (2) S + F = 54.2%, (3) S + F + P = 60.9%, and (4) S + F + P + C = 59.9%. Thus, in a majority of cases (55%), study models alone provided adequate information for treatment planning, and incremental addition of information from other types of diagnostic records made small differences.     

Orthodontic treatment planning: do orthodontists treat to cephalometric norms?

Cephalometric norms are important to orthodontists in their diagnosis, treatment, and evaluation of orthodontic treatment outcomes. The purpose of the present study is to establish if orthodontists treat and finish their cases to the cephalometric means or norms. Pre- and post-cephalometric radiographs and dental casts of 35 orthodontically treated cases were analyzed. The Kappa test, Wilcoxon Signed-Rank test, Paired t- test, and Z-test were used for the statistical analysis of the data. The result revealed that orthodontists do not reach the cephalometric mean values post-treatment. However, sagittal maxillomandibular relationship and interlabial gap are the main areas of improvements. This leads to improvement of soft tissue esthetics by camouflaging the skeletal and dental relationship.     

Early Orthodontic Treatment of Class-III Malocclusion in Germany

In order to evaluate current attitudes to early interceptive treatment, 2001 orthodontic offices in Germany were asked to fill in a questionnaire comprising the following topics: indication, appliances for the early correction of Class-III malocclusions, diagnostic records, duration, and benefits to overall therapy. Based on the 677 evaluable questionnaires, the following statistically significant conclusions could be drawn: 92.6% of the orthodontists see Class-III malocclusion as an indication for early treatment. Early treatment of severe crowding, diastemata, Class-II malocclusion, deep bite, increased overjet and impacted incisors was declined by most orthodontists. The interceptive treatment of further malocclusions was controversially discussed. Functional appliances (67.5%), in particular the Fr?nkel III (47.3%), were dominant in correction of Class-III malocclusions. Typical orthodontic records relating to early interceptive treatment include panoramic radiographs, lateral headfilms, photos and dental casts. 2.5% of the orthodontists routinely take a hand-wrist radiograph. Although recently published studies support the use of facial masks in theory, they are rarely used in practice. To what extent early interceptive treatment of Class-III malocclusion influences the overall treatment is the subject of further studies.     

Does rapid maxillary expansion affect the eruption of upper third molars?

OBJECTIVE: To test the hypothesis that there is no difference in the movement of the upper third molars between rapid maxillary expansion (RME) and non-RME patients. MATERIALS AND METHODS: This study was performed on 30 patients divided into two groups. The study group included 20 patients who had maxillary narrowness and bilateral maxillary third molars and who had undergone RME application. The control group of 10 patients had a bilateral crossbite, had bilateral maxillary third molars, and did not receive orthodontic treatment. The records included lateral and frontal cephalometric films and maxillary plaster models. In the study group, records were taken before expansion (T1), after expansion (T2), and at the retention period (T3). T2 records were not taken in the control group because this period was too short to observe any changes. Friedman tests were used to observe within groups, and the Mann-Whitney U-test was used to see the differences between groups on films and casts. RESULTS: Frontal films showed that vertical eruption occurred after the retention period in the RME cases. Cephalometric films revealed that the angular eruption occurred immediately after expansion. However, the results were not significant with respect to the control group. CONCLUSION: The hypothesis was rejected. Rapid maxillary expansion affects maxillary third molar movement during and after the RME procedure. RME may indicate upper third molar eruption, but the final position of third molar was not different compared to the normal growth pattern.     

Value-addition of lateral cephalometric radiographs in orthodontic diagnosis and treatment planning

ObjectiveTo investigate the value-addition of obtaining lateral cephalometric radiographs during the treatment planning phase of orthodontic treatment.Materials and MethodsThe records of 100 orthodontic patients were presented to seven scorers during two phases that were 6 weeks apart. In the first phase, scorers completed a seven-question survey with questions regarding treatment planning. They were given various diagnostic records that did not include a lateral cephalometric radiograph. Six weeks later, the same scorers completed the same survey for the same patient cases with the same diagnostic records that additionally included a lateral cephalometric radiograph. Correlation coefficients were used to calculate intrarater agreement and inter-rater agreement within the study.ResultsCohen''s kappa values showed moderate to almost perfect agreement for the majority of survey questions. Intrarater agreement ranged between 0.430 and 1. Cronbach''s alpha reliability statistics showed good interrater agreement for all questions in the survey. Agreement ranged from 0.710 to 0.913 across the survey questions. Diagnosing Angle classification of occlusion had the highest level of agreement and differentiating between skeletal and dental malocclusion had the lowest level of agreement.ConclusionsThe lateral cephalometric radiograph is not a necessary diagnostic tool for most cases in orthodontic diagnosis and treatment planning. Weighing the usefulness of a lateral cephalometric on a case-by-case basis should be recommended to align with the principle of ALARA (as low as reasonably achievable), especially in a primarily pediatric population.     

Effects of a bonded rapid maxillary expansion appliance during orthodontic treatment.

The aim of this prospective study was to evaluate changes in the transverse plane following use of an acrylic bonded rapid maxillary expansion (RME) appliance in growing individuals during the active phase of treatment. The sample comprised 14 consecutively treated orthodontic patients (11 girls, 3 boys) who required the use of an RME device on the basis of their individual treatment plans. The mean patient age at the start of treatment was 12.8 years, and the mean overall treatment time was 3.08 years. Seven posteroanterior cephalometric and two dental cast measurements were assessed. Repeated measure analysis of variance and Duncan's multiple range test were used to assess treatment changes. Lower nasal and maxillary base widths and angles, and upper intermolar width increased significantly during RME treatment. Upper intermolar and intercanine widths measured from the dental casts also increased significantly. Except for upper intercanine width, all measurements remained constant at the end of orthodontic treatment. The results of this study suggest that dentoskeletal changes in the transverse dimension following the use of an acrylic bonded RME are maintained satisfactorily at the end of fixed appliance therapy.     

Jarabak 's cephalometric analysis of Brazilian black patients

The treatment of skeletal disharmonies presents better results when performed during the growth period. The physical changes that occur in every individual express growth, which is ruled by genetic, general and environmental factors. In order to identify such disharmonies and hence concentrate the clinical actions during treatment and influence facial growth, cephalometrics appears as a useful a diagnostic tool for identifying facial growth patterns or growth direction. Jarabak's cephalometric analysis is used to assess facial growth pattern of subjects with normal occlusion or malocclusions. The purpose of this study was to obtain mean values for cephalometric measurements from Jarabak's cephalometric analyses of black Brazilian subjects resident in the city of Piracicaba, S?o Paulo state, Brazil and vicinities, who presented Class I molar relationship with normal overjet and overbite, mild or no tooth crowding or spacing, and no history of orthodontic treatment. A sample of 37 stone plaster casts and 37 lateral teleradiographs from both male and female individuals aged 10 to 14 years was evaluated. Data were analyzed statistically by Student's t-test at 5% significance level. There was no significant differences between genders. The cephalometric measurements obtained in this study were similar to the Jarabak's standards, except for S-N mean value in females (66.50 mm +/- 3.16), which was significantly lower than the standard.     

模型重叠评价上颌切牙牙轴变化的可靠性研究

目的 探讨运用模型重叠的方法 评价上颌切牙牙轴变化的可靠性。方法 选取28例完成正畸治疗的患者,入选标准包括上颌对称拔除第一或者第二前磨牙,无偏斜的上颌中线等。治疗前、后拍头颅侧位片和制取寄存模型。头影测量分析头颅侧位片的中切牙牙轴变化,模型用Roland LPX-1200三维点激光扫描仪数字化,基于腭部区域重叠,使用测量软件(Rapidform 2006)分析治疗前后中切牙牙轴变化。用SPSS10.0统计软件对两种测量方法的结果行统计分析。结果 本研究样本的头影测量显示切牙牙轴平均内收14.47°,模型测量中切牙有14.70°的牙冠舌向移动。两种测量方法没有显著性差异。结论 用模型重叠的方法分析切牙的牙轴变化可以取得与头影测量一致的结果。?     

Procuste cephalometry

Procrustean cephalometrics employs Procrustes's methods to analyze cranio-facial and orthodontic structures. Using this technique, which is structured on a rigorous mathematical base, orthodontists can avoid the biases and limitations of traditional analyses based on index angles and linear measurements. The starting data are the coordinates of the anatomic landmarks discerned on a profile cephalometric X-ray. Employing this data, orthodontists can calculate patients' type and stage of growth. These factors, representative of the normal variability of each patient, make it possible for the orthodontist to calculate an individualized reference base: a harmonious face in good balance of the same type and at the same growth stage as the patient. Finally, orthodontists make the best possible superimposition of this personalized, "ideal" radiographic sketch on the patient's headplate, by using anatomic landmarks, not a reference plane, to determine the areas that are out of balance and identify the anomalies that will need to be corrected during treatment.     

A validation study of three indexes of orthodontic treatment need in the United States

Abstract The purpose of this study was to compare the reliability and validity of three occlusal indexes of orthodontic treatment need in predicting the opinion of treatment need of a panel of 18 orthodontists. A set of 160 study casts representing all types of malocclusion was used. The casts were scored with the following occlusal indexes: the Index of Orthodontic Treatment Need (IOTN), the Handicapping Labio-Lingual Deviations index (HLD), and the Handicapping Malocclusion Assessment Record (HMAR modified). The diagnostic accuracy or validity of each index was calculated using the mean opinion of the orthodontic raters as a “gold standard”. Receiver Operating Characteristic curves were plotted for each index. The overall diagnostic accuracy, as determined by percent area under the curve, was similar for each index: IOTN 98.6%; HLD 96.1%; HMAR 96.6%. The score optimizing the sensitivity and specificity relationship for each index was as follows: IOTN (dental health component) 4; HLD 13; HMAR 12. These results indicate that the three occlusal indexes provided valuable information for determining orthodontic treatment need.     

Clinical Profile of Rapid Maxillary Expansion—Outcome of a National Inquiry

BACKGROUND: Rapid maxillary expansion (RME) is a therapeutic orthodontic option with a long history, and there are many reports in the literature reporting widely divergent results concerning the appliance efficacy and many different treatment protocols. We aimed to evaluate the treatment protocols and clinical experiences with RME via a national inquiry of orthodontists to identify the status quo of RME in clinical daily routine. METHOD: Within the framework of an anonymous questionnaire, 2003 orthodontists and members of the German Orthodontic Society (DGKFO) were asked to report on their clinical experiences with RME. The standardized questionnaire covered clinical indications, dentition period at the time of insertion, mode of activation, retention time, observed side effects, and the reasons for requiring surgical assistance. RESULTS: The data from 487 questionnaires could be evaluated. The only indication for RME named by a large majority of responders was transversal maxillary deficiency. The average extent of the transversal deficiency amounted to 5.29 +/- 2.25 mm (median 5 mm). Most orthodontists (87.7%) employed RME in the permanent dentition of adolescents; it was significantly less frequently applied in the primary dentition or adults. Answers regarding the mode of activation varied greatly. The most frequent mode of activation was "1-2 activations a day" independent of the dentition period. 64.5% of the orthodontists reported buccal tipping of the anchorage teeth. No correlation was detected between mode of activation, time of insertion and observed side effects. 60% of the orthodontists reported a retention period of between 3 and 6 months (median 4.5 months). With an average age of 19.28 years, 79.3% assessed chronological age as a limiting factor for conventional RME. It was not possible to identify a homogeneous diagnostic procedure for the indication of surgical assistance. CONCLUSIONS: Although RME has a long clinical history, no standardized treatment protocols exist. Randomized clinical trials are necessary to make clear-cut clinical recommendations on the use of RME, as required by the tenets of evidence-based medicine and quality assurance.     

An inference modeling of human visual judgment of sagittal jaw-base relationships based on cephalometry: part II.

In a clinical situation, visual judgment of sagittal jaw-base relationships is described and handled as fuzzy terms, such as "slight" skeletal 3 tendency or "relatively severe" skeletal 2. The purpose of this study was to develop an inference system in order to be able to describe the degree of certainty for sagittal skeletal discrepancy automatically and in a mathematical way. Orthodontic records of 137 adult female patients were judged by 3 orthodontists. Based on these data and the multiple regression model described in Part I of this study, we developed an inference system that consisted of 2 membership functions and 6 incorporating rules. The performance reliability of the system was tested for 175 female adult cases by 7 orthodontic experts. In 97% (170 of 175) of the cases, the orthodontic experts agreed with advice proposed by the inference system. We conclude that the current model is an effective means of deriving the opinion of an experienced clinician from a cephalometric tracing and provides an interesting insight into how orthodontists are influenced by the face when attempting to judge the sagittal relationship clinically. In addition, the current system would be an initial stage in the development of the decision-making system for the orthodontic diagnosis and treatment planning.     

Cephalometric variables as predictors of Class II treatment outcome

Cephalometric analysis of skeletodental features is accepted as an integral part of orthodontic diagnosis and treatment planning. This assumes that diagnostic cephalometric variables affect prognosis and thus help reduce malocclusion severity, which is the aim of orthodontic treatment. The aim of this study was to assess the predictive value of 41 commonly used cephalometric parameters with regard to pretreatment severity and treatment outcomes. Pretreatment severity was assessed by using the Peer Assessment Rating (PAR) occlusal index, an instrument that has been shown to be valid and reliable. Treatment outcomes consisted of (1) posttreatment malocclusion severity (post-PAR), (2) relative improvement (percent PAR reduction), and (3) treatment duration. Complete records, including cephalograms, of 223 treated Class II cases were analyzed by means of separate multiple linear regression models. Each of the outcome variables and the pretreatment severity served as the respective dependent variables, and the cephalometric parameters served as the independent or predictor variables. The cephalometric parameters explained 39.2% of the pretreatment severity variance, 17. 9% of posttreatment severity variance, 15.7% of relative treatment improvement variance, and 20.0% of treatment duration variance.     

Validity of the Index of Complexity, Outcome, and Need (ICON) in determining orthodontic treatment need

Occlusal indices are used to determine eligibility for orthodontic treatment in several publicly funded programs. The Index of Complexity, Outcome, and Need (ICON), based on the perception of 97 orthodontists from 9 countries, has been proposed as a multipurpose occlusal index. The aim of this study was to investigate the validity of the ICON as an index of orthodontic treatment need compared with the perception of need as determined by a panel of US orthodontists. One hundred seventy study casts, representing a full spectrum of malocclusion types and severity, were scored for orthodontic treatment need by an examiner calibrated in the ICON. The results were compared with the decisions of an expert panel of 15 orthodontic specialists from the central Ohio area. The simple kappa statistic (0.81) indicated very high agreement of the index with the decisions of the expert panel. The sensitivity (94%), specificity (85%), positive predictive value (92%), negative predictive value (90%), and overall accuracy of the ICON (91%) also confirmed good agreement with the orthodontic specialists. The panel found that 64% of the casts required orthodontic treatment; the ICON scores indicated that 65% of the cases needed treatment. There was agreement between the expert panel and the index in 155 of the 170 cases. These results support the use of the ICON as a validated index of orthodontic treatment need.     

A comparison of the reliability and validity of 3 occlusal indexes of orthodontic treatment need.

Several occlusal indexes are currently used to ascertain eligibility for orthodontic treatment. A comparison of 3 indexes of orthodontic treatment need was made with the consensus opinion of a panel of 15 experienced orthodontists. Sets of study casts (170) representing the full spectrum of malocclusions were selected. An examiner, calibrated in the Dental Aesthetic Index, the Handicapping Labiolingual Deviation with the California Modification, and the Index of Orthodontic Treatment Need, scored the casts. The panel of orthodontists individually rated the same casts for their degree of orthodontic treatment need. The mean rating of the panel on the need for treatment was used as the gold standard for evaluating the validity of the indexes. Intrarater and interrater reliability was high (kappa > 0.8). Overall accuracy of the indexes, as reflected in area under receiver-operating characteristic curves, was also high: Dental Aesthetic Index, 95%; Handicapping Labiolingual Deviation with the California Modification, 94%; and Index of Orthodontic Treatment Need, 98%. Cutoff points for the indexes that resulted in the closest agreement with the gold standard differed from the published cutoff points for the indexes. The indexes appear to be valid measures of treatment need as perceived by orthodontists. The published cutoff points for the indexes were more conservative in assigning patients for treatment than a panel of orthodontists. However, adjusting the cutoff points moved all 3 indexes into close agreement with the experts.     

An evaluation of the use of digital study models in orthodontic diagnosis and treatment planning

The purpose of the present study was to determine the diagnostic and treatment planning value of digital models when compared with plaster study casts. In addition, the level of orthodontic experience of the examiner was assessed to determine whether this would have an influence on the decision-making process. Thirty randomly selected orthodontic patients from the Department of Orthodontics at the University of Alabama were selected for the study. From the 30 record sets, seven were selected attempting to mirror cases required for presentation to the American Board of Orthodontics. The seven evaluators were divided into two groups on the basis of their level of orthodontic experience. Initially, each evaluator assessed each patient record. Each evaluator was given a standardized questionnaire which recorded the evaluator's diagnosis based on use of the digital study models (T1). Regardless of whether the evaluator requested a review of the plaster study casts, the evaluator was given the plaster study casts. The evaluator then, using the plaster casts, filled out another identical questionnaire (T2). A chi-square test was used to determine any group differences in the frequency of changed diagnostic characteristics, treatment mechanical procedures, or proposed treatment plans after evaluating plaster study models. The statistical significance selected was P = .05 level of significance. The results showed that 12.8% of diagnostic characteristics, 12% of treatment mechanic procedures, and 6% of proposed treatment plans changed after T2. The results of the present study indicate that in the vast majority of situations digital models can be successfully used for orthodontic records.     

Longitudinal effects of rapid maxillary expansion

OBJECTIVE: To evaluate the long-term effects of rapid maxillary expansion (RME) via banded expanders in the sagittal and vertical facial planes. MATERIALS AND METHODS: The sample consisted of 25 patients who had undergone RME (with either Haas-type or Hyrax hygienic expanders) followed by standard edgewise orthodontic therapy. This sample was compared with a group of 25 patients who had edgewise treatment only and with a control nontreatment group of 26 subjects, matched by age and gender with the patients of the other two groups. Lateral cephalograms were taken before treatment (T1), at the end of treatment (T2), and at 3 years posttreatment (T3), comprising a 5-year average time of observation. RESULTS: RME treatment, in the long-term, did not influence the sagittal position of the apical jaw bases or the facial vertical dimension. CONCLUSION: Unfavorable cephalometric changes resulting immediately after RME are temporary, and therefore concerns about using RME in patients with vertical growth patterns or an extremely convex facial profile are not substantiated.     

Three-dimensional imaging: The caseWestern Reserve University method

The goal of this project was to create a lifelike digital record of human dentofacial morphology. Traditionally, orthodontists have relied on a lateral and sometimes a frontal cephalometric radiograph, three facial and three intraoral photographs, and upper and lower dental study casts to capture the dentofacial morphology of their patients. Creating a unified digital record of dentofacial morphology requires all records to share the same space. Therefore, to be lifelike, all records should eventually be positioned within a computer (on-screen) representation of the three-dimensional (3D) space of the patient's head. This requirement necessitated that radiographic and facial surface morphology be rendered in 3D and that 3D study casts be converted to digital format. This article describes the Case Western Reserve University method for (1) rendering the lateral and frontal biorthogonal cephalogram pairs in 3D; (2) capturing the 3D surface of the human face; (3) converting the plaster dental cast data to a 3D digital record; and (4) integrating lateral and frontal radiographs, facial surface scans, and digital study models into a single 3D patient record. In addition, the creation of standard 3D cephalometric wireframes using the Bolton Standard subjects is described. Finally, two case reports are presented to show the use of this 3D digital record to analyze craniofacial hard and soft tissue changes brought about by Le Fort I maxillary advancement surgery. In the case reports, traditional cephalometric superimpositions are compared with 3D color-coded surface superimpositions of the preoperative and postoperative facial images. The advantages and disadvantages of this digital outcomes assessment method are discussed in this presentation of a model for the future 3D orthodontic patient record.