The Relationship between Posttreatment Smile Esthetics and the ABO Objective Grading System: Class I Extraction versus Non-Extraction Cases.

OBJECTIVE: This study aimed to evaluate the relationship between the components of the objective grading system developed by the American Board of Orthodontics (ABO) and smile esthetics in Class I extraction vs non-extraction cases. METHODS: A total of 40 extraoral smile images of orthodontically treated (20 extraction and 20 non-extraction) cases in the age group of 13-30 years and Class I skeletal malocclusion with an average mandibular plane angle were selected. Smile images were rated only by the orthodontist, and this panel included 12 members. Scoring of post-treatment dental casts and panoramic radiographs of each patient was performed by 1 investigator per the guidelines of the ABO grading system. The Pearson correlation coefficient and logistic regression analysis were used to ascertain whether the scores of the ABO grading system could foretell whether a smile would be "attractive" or "unattractive." RESULTS: The correlation between all the criteria of the ABO grading system and attractiveness of the smile was extremely weak. The r values ranged from -0.53 to 0.37 for extraction cases and -0.63 to 0.003 for non-extraction cases (p>0.05). Neither individual parameters nor total scores of the ABO grading system could predict whether the smile was attractive or unattractive in either group. CONCLUSION: No correlation was found between post-treatment ABO grading and smile esthetics in patients with extraction or non-extraction. Hence, this study recommends that ancillary soft tissue variables have to be incorporated into the grading system to evaluate a smile.

Comparative assessment of sagittal skeletal discrepancy: a cephalometric study.

BACKGROUND AND OBJECTIVES: Evaluating the sagittal apical base relationship during orthodontic diagnosis and treatment planning is an important step. This study was aimed at comparison of Beta angle, ANB angle and Wit's appraisal for assessment of sagittal skeletal discrepancy. MATERIALS AND METHODS: Eighty six young adults (43 female and 43 male) were selected from the patient's reporting to Department of Orthodontics, College of Dental Sciences, Davangere, India. Family lineage was studied to know the nativity of Davangere. The standardized pre-treatment lateral cephalogram of the chosen sample was traced. The sample was divided into three skeletal pattern groups: Class I, Class II and Class III, based on the ANB angle and profile, Beta angle was assessed in each group. STATISTICAL ANALYSIS: The data was subjected to statistical analysis student's t-test, ANOVA test and correlation and regression analysis, using the software namely SPSS Software version 13. Microsoft word and Excel were used to generate graphs and tables. RESULTS: In the local Davangere population, Class I skeletal pattern group exhibited Beta angle between 26°-34°, Beta angle less than 27° was found in Class II skeletal pattern, and Beta angle greater than 32° was seen Class III skeletal pattern. The coefficient of variation of Beta angle in all the three groups was significantly homogenous compared to ANB angle and Wits appraisal. The correlation and regression analysis of the total sample indicated a highly significant correlation between Beta angle and ANB angle (p<.001), and between Beta angle and Wits appraisal (p<.01). CONCLUSION: Beta angle can be used to classify subjects into different skeletal patterns. The Correlation and regression analysis for the total sample suggests a highly significant relation between Beta angle and ANB angle and, between Beta angle and Wits appraisal. It can be more reliably used to assess sagittal jaw discrepancies than ANB angle and Wits appraisal.

Modified transpalatal arch for molar intrusion.

A simple modification of transpalatal arch to overcome the problems caused by conventional transpalatal arch.

Cephalometric assessment of effect of head rotation toward focal spot on lateral cephalometric radiographs.

INTRODUCTION: The patient's head can be slightly rotated sagittally vertically or transversely with the head holding device. Because of such improper positions due to head rotation, an error can occur in cephalometric measurements. The purpose of this study was to identify the projection errors of lateral cephalometric radiograph due to head rotation in the vertical Z-axis toward the focal spot. MATERIALS AND METHODS: Ten human dry skulls with permanent dentition were collected. Each dry skull was rotated from 0° to +20° at 5° intervals. A vertical axis, the Z-axis, was used as a rotational axis to have 50 lateral cephalometric radiographs exposed. Four linear (S-N, Go-Me, N-Me, S-Go) and six angular measurements (SNA, SNB, N-S-Ar, S-Ar-Go, Ar-Go-Me, AB-mandibular plane angle) were calculated manually. RESULTS: The findings were that: (1) Angular measurements have fewer projection errors than linear measurements. (2) The greater the number of landmarks on the midsagittal plane that are included in angular measurements, the fewer the projection errors occurring. (3) Horizontal linear measurements have more projection errors than vertical linear measurements. CONCLUSION: The angular measurements of lateral cephalometric radiographs are more useful than linear measurements in minimizing the projection errors associated with head rotation on a vertical axis toward the focal spot.

An esthetic treatment outcome of orthognathic surgery and dentofacial orthopedics in class II treatment: a cephalometric study.

AIM: The main objective of any orthodontic treatment is to achieve well-established stable occlusal relationship with a definite positive change in facial profile. The purpose of this study was to determine, if such a goal is achievable for patients who could be classified as borderline surgical cases without the invasive use of the actual surgery or, with the use of the recently developed and rapidly spreading fixed functional appliance system (Forsus) and a comparison of the esthetic treatment outcome with the two systems. MATERIALS AND METHODS: Twelve postadolescent borderline skeletal class II patients with a deficient mandible. All the patients used in the study were treated by a preadjusted edgewise appliance for presurgical decompensation with or without extractions and for postsurgical finishing and detailing. Out of the 12 patients six were treated with bilateral saggital split osteotomy (BSSO) and six were treated with fixed functional appliance (Forsus). RESULTS: The results suggested that although surgical patients had a better mandibular advancement, profile reduction, and marked improvements in soft tissue structures, the patients who had undergone fixed functional therapy also had comparable improvement in the above aspects. In the maxilla there was no change in cases treated with surgery but in case of Forsus some retraction of anterior dental segment was evident. CONCLUSION: In surgical group, class II malocclusion correction was more skeletal than dental, whereas in functional group class II malocclusion correction was more dental than skeletal. CLINICAL SIGNIFICANCE: Looking at the common surgical risks, cost-effective and postsurgical problems and patients with borderline class II malocclusion, fixed functional therapy is a valuable adjunct in the management of class II malocclusion.