Aim:To determine the efficiency of erbium: Yttrium aluminum garnet (Er:YAG) laser with Environmental Scanning Electron Microscope (ESEM) and shear bond strength analysis as a method of recycling stainless steel orthodontic brackets and compare with other methods of recycling.Materials and Methods:Eighty samples of extracted premolar teeth bonded to SS brackets were tested for rebonded shear bond strength after recycling by four methods and compared with a control group of 20 samples. These 80 samples were randomized into four groups which were recycled by four methods, namely, sandblasting, thermal method, adhesive grinding by tungsten carbide bur, and Er: YAG laser method. After recycling, ESEM and shear bond strength analysis were used to analyze the efficiency of the recycling methodsResults:Er: YAG laser group was found to be having the greatest bond strength among the recycled brackets (8.33±2.51 followed by the sandblasting at 6.12±1.12 MPa, thermal and electropolishing at 4.44±0.95 MPa, and lastly the adhesive grinding method at 3.08±1.07 MPa. The shear bond strength of Er: YAG laser group was found to be having no statistically significant difference with that of the control group (P>0.05 and had statistical signifance with sandblasting, thermal and electropolishing and adhesive grinding groups at P>0.001. ESEM analysis showed complete removal of adhesive from the brackets recycled with Er: YAG laser which mimicked that of the control group.Conclusion:Er: YAG laser (2940 nm) was found to be the most efficient method for recycling, followed by the sandblasting, thermal, and the tungsten carbide methods, which had the least shear bond strength value and is not fit for clinical usage.

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).

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.