Majalah Kedokteran Gigi Indonesia. August 2018; 4(2): 102 - 106 ISSN 2460-0164 (print) ISSN 2442-2576 (online) 102 Evaluation of surface roughness of the bracket slot before and after burning Raudhatul Jannah*, Bergman Thahar**, Endah Mardiati**, Ida Ayu Evangelina** *Orthodontic Specialis Study Program, Faculty of Dentistry, Universitas Padjajaran, Bandung, West Java, Indonesia **Department of Orthodontics, Faculty of Dentistry, Universitas Padjajaran, Bandung, West Java, Indonesia *Jl Sekeloa Selatan No 1, Bandung, West Java, Indonesia; e-mail: rjannah2209@gmail.com Submitted: 19 th September 2017; Revised: 21 st January 2018; Accepted: 1 st March 2018 ABSTRACT Slot bracket base is one important element to enable sliding movement of the archwire. Bracket reconditioning by means of burning changes the surface roughness of slot bracket base. The heat above 450 °C shows microstructure changes of the slot surface. On this basis, the present study aims to evaluate surface roughness changes of the slot bracket base before and after reconditioning by means of burning. Sixteen premolar brackets standard edgewise were divided into two groups each consisting of eight brackets. These two groups were tested at three different points using Scanning Electron Microscopy (SEM), with 3000 times of magnifcation. Subsequently, group A was burned for 5 sec- onds (approximately 450 °C) and group B was burned for 10 seconds (approximately 643 °C). After treatment, these two groups were tested for the second time using Scanning Electron Microscopy (SEM), with 3000 times magnifcation and the images were analyzed using a discrete scale quantitative classifcation. Afterwards, the data were analyzed using ANOVA (p ≤ 0.05) and post hoc analysis. The result showed that surface roughness of the slot bracket base burned for 10 seconds experienced more signifcant change than that of bracket burned for 5 seconds and that of the control bracket (p ≤ 0.05). Bracket reconditioning using burning either for 5 to 10 seconds change the surface roughness of the slot bracket base. Keywords: Scanning Electron Microscopy (SEM); slot bracket base; surface roughness Majalah Kedokteran Gigi Indonesia Vol 4 No 2 – August 2018 ISSN 2460-0164 (print), ISSN 2442-2576 (online) Available online at https://jurnal.ugm.ac.id/mkgi DOI: http://doi.org/10.22146/majkedgiind.28387 INTRODUCTION Orthodontists often have to deal with the bracket that comes loose from the patient’s teeth to be reattached to its position. 1 This problem may lead to various disturbances, time-consuming maintenance and additional cost for the repair. When the previously used mesh bracket is not damaged, the orthodontists only need to recondition the bracket. 2 Reconditioning the bracket is mainly chosen because it does not affect the retractive properties of the bracket base to the teeth. 3 Previous research reveals that the ideal temperature level that affects metal elements in bracket reconditioning ranges from 400 °C to 900 °C because at this temperature levels, the microstructure changes in bracket surface, size and mechanical properties of the bracket take place. The heat used in the reconditioning process causes chromium to bind to carbon to form deposits of chromium carbide (Cr 23 C 6 ) on the surface, resulting in reduced surface roughness and ability to resist corrosion. This image of microstructural elements on the surface is referred to as an “island formation” which is an arrangement of metal grains bounded by a carbide area called the grain boundary. 2,4 MATERIALS AND METHODS As an experimental laboratory research, the researcher conducted the in vitro test and shooting process at the Center for Textiles, Bandung in June 2017. This study used sixteen standard premolar edgewise brackets as the research sample which was determined based on the formula. First, these sixteen standard edgewise premolar bracket pieces were divided randomly into group A and B. These samples were tested to classify their surface rough- ness in three different basic slots using a 3000x magnifcation SEM. These tested bracket pieces RESEARCH ARTICLE