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OBJECTIVES:To compare the accuracy of the linear measurements made on pre- and posttreatment three-dimensional (3D) scanned digital models with conventional plaster study models.MATERIALS AND METHODS:The study was conducted on pre- and posttreatment study models of 132 patients. A 3D model scanner was used to scan the plaster models to form 3D digital models. The measurements were made on the plaster models using digital Vernier calipers, and the 3D digital models were assessed for similar measurement using a software of the model scanner. The intraclass correlation for intraoperator error showed good correlations between the measurements made on conventional plaster models and digital models.RESULTS:Although the comparison of the linear measurements made by conventional and digital methods on both pre- and posttreatment study models using intraclass coefficient showed a good correlation, analysis of variance showed significant mean differences in the measurements of multiple variables in both the groups. The number of variables showing significant differences was more in the pretreatment group. The measurements obtained by Vernier calipers were generally higher than those of scanned pre- and posttreatment study models.CONCLUSION:The linear measurements made by conventional and digital methods showed statistically significant mean differences. The accuracy of recording can be affected by the severity of pretreatment malocclusion, but the deviations were not large enough to contradict the use of the digital models for orthodontic records.

Objectives To evaluate the success rate, treatment duration, and pain perceived during forced eruption of maxillary palatally impacted canines using the K9 and Ballista springs. Materials and Methods Thirty unilateral palatal canine impactions of moderate and difficult category as determined by KPG index (score between 10 and 19) were enrolled. Group 1 comprised canine impactions managed with K9 springs, and Group 2 comprised Ballista springs. Block randomization and opaque sealed envelopes were used for allocation. The success rate and treatment duration (application of force to ligation of the impacted canine into the initial alignment archwire) were recorded. Pain perception was evaluated on a 10-point visual analogue scale (VAS) and modified McGill Pain Questionnaire. Chi-square test and Mann-Whitney U-test were used to compare the groups. Results The success rate for eruption of palatally impacted canines was 100%. The average treatment duration was 296.13 ± 96.45 days and 311.93 ± 94.34 days, respectively for Group 1 and Group 2. VAS scale scores for pain were greater for Group 2 compared to Group1, and the differences were statistically significant at all time intervals except at T1. The frequency of none and mild pain was significantly greater at all time intervals in both groups. Conclusions The impacted canines of moderate and difficult category were erupted with a 100% success rate and similar treatment duration with both interventions. The pain scores of Ballista springs were greater after 24 hours of force application.

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<b><i>Objective:</i></b> The objective of this study is quantitative assessment of nasalance for skeletal Class I (normative values), Class II, and III malocclusion in the English language for the North Indian population and to compare the normative values with the nasalance scores obtained from individuals with skeletal Class II and III malocclusion and to evaluate the normative values as a function of gender. <b><i>Material and Methods:</i></b> The study was conducted on a total sample of 200 patients with 100, 50, and 50 in group 1 (control group, Skeletal Class I), group 2 (Skeletal Class II), and group 3 (Skeletal Class III), respectively. ANB angle (anteroposterior angle formed by point A, nasion, and point B) measured on lateral cephalogram was used to categorize the patients into 3 groups. The normative nasalance scores were compared for males and females in the control group. The nasalance scores of skeletal Class II and III subjects were compared to the combined normative scores of the control group. The NasalView was used for the objective assessment of nasalance. Oral syllables (/pa/and/pi/), nasal syllables (/ma/and/mi/), and 3 passages (Zoo passage, Rainbow passage, and Nasal sentences) were used to determine the nasalance scores. <b><i>Results:</i></b> The intragroup comparison of nasalance scores in group 1 showed statistically significant differences for different stimuli. The gender-related comparison showed no statistically significant differences in nasalance scores. The intergroup comparison of nasalance scores for skeletal malocclusion showed no statistically significant differences for different stimuli except statistically significant lower nasalance values for nasal sentences in group 3 compared to the control group. <b><i>Conclusion:</i></b> The study concluded that the nasalance scores for nasal sentences in skeletal Class III malocclusion were significantly lower than in the control group and were not statistically significant between the 3 groups for all other stimuli.