The dearth of prolonged, prospective evaluation, the relative impact of fixed and the removable retainers eventualities can only be speculated upon. Hence in this study was to compare the stability of orthodontic outcomes with fixed and removable retainers over a period of at least 4 years. Of the 82 participants included in the previous RCT, data were obtained from 48 at 18-month follow up. Orthodontic stability was based chiefly on the irregularity of the mandibular incisors using Little’s Irregularity Index to assign a cumulative score for the contact point displacement in 4 the mandibular inter-canine region. Eighty-two participants were enrolled in the original RCT. After adjusting for confounders, the median between-groups difference was 1.64mm higher in those wearing vacuum-formed retainers (P= 0.02; 95% CI: 0.30, 2.98mm). No statistical difference was found between the treatment groups in terms of inter-canine (P= 0.52; 95% CI: -1.07, 0.55) and inter-molar widths (P= 0.55; 95% CI: -1.72, 0.93), arch length (P= 0.99; 95% CI: -1.15, 1.14) and extraction space opening (P= 0.84; 95% CI: -1.54, 1.86).

Objective: To identify the best-suited cephalometric parameter for assessing the sagittal skeletal discrepancy in the Indian population. Design: An in vitro, observational, single-blinded, retrospective study. Setting: Department of Orthodontics and Dentofacial Orthopaedics. Methods: A total of 94 lateral cephalograms were used in this study. The study involved one key person and two examiners. The key person collected the radiographs, coded, analysed and classified them into three groups (skeletal classes I, II and III). Subsequently, the coded radiographs were independently analysed by the two examiners. They classified the cases by matching a minimum of 6 out of 11 parameters. On completion of diagnosis by the examiners, the samples were decoded and matched with the original diagnosis given by the key person. The samples in which identification of a particular cephalometric parameter matched the original evaluation as given by the key person was regarded as correctly diagnosed. The number of correctly assessed cases was used to judge the diagnostic performance of all the parameters in all the cases. Cross-validation of the method was performed, and a diagnostic algorithm was developed for diagnosis. Results: β angle and Pi angle showed a positive predictive value of 1 in both skeletal class I and II cases. ANB angle, W angle and HBN angle showed a positive predictive value of 1 in skeletal class III cases. Conclusion: No single cephalometric parameter can independently be used to diagnose sagittal skeletal discrepancy in all cases. However, a conclusive diagnosis on the type of sagittal skeletal malocclusion can be made by using a simple and easy to use diagnostic algorithmic process having a combination of cephalometric parameters.

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Aim: Purpose of this study was to evaluate the efficacy of 3 different types of retainers (Hawley removable, Essix removable and Fixed) of the mandibular and maxillary anterior sextant and to assess patient perception of crowding. Methodology: A retrospective study of 80 patients was carried out for a time period of 1-2 years into retention. E models (digital models) were assessed pre- and post-orthodontically using Little’s Irregularity Index. The amount of Irregularity was compared for 3 retention groups (Hawley, Essix and Fixed). Relapse was also subjectively measured. Results: Increase in the Irregularity Index of the mandibular incisors was observed after wearing Hawley retainers, including crowding which was significantly more than patients with Fixed retainers. Conclusion: Hawley retainers allow for more mandibular incisor movement rather than the Fixed retainers.