ORIGINAL RESEARCH Journal of Dentomaxillofacial Science (J Dentomaxillofac Sci ) August 2017, Volume 2, Number 2: 91-94 P-ISSN.2503-0817, E-ISSN.2503-0825 91 http://jdmfs.org © 2017 JDMFS. Published by Faculty of Dentistry, Hasanuddin University. All rights reserved. CrossMark Abstract Objective: The aim of this study is to know the impact of mouth- rinsing using chlorhexidine gluconate 0.2% with the number of plaque-causing bacterial colonies in fixed orthodontic users. One of the most common problems is malocclusion. The solution is to do orthodontic treatment but the side effect is very susceptible to having poor mouth hygiene due to oral microflora which has changed and the difficulty to clean the appliance. Material and Methods: This research type is quasi-experimental with pretest and posttest with control group design. The sample, which consist of 30 college students of fixed orthodontic users was divided into two groups where the first group was given the chlorhexidine gluconate 0.2% and the second group was given aqua dest. A swab on teeth samples were taken before treatment, on 7th day and 14th day to observe the number of bacteria colonies by cup-counting method at Microbiology Laboratory, Pharmacy Faculty of Hasanuddin University. Results: The results of repeated ANOVA and post hoc bonferroni test by using SPSS program (23rd version) showed that the value baseline was 333.86±11.8, on 7th day was 229.26±6.3 and on 14th day was 127.40±7.8 with the p-value=0.000. The result of general linear model analysis on 7th day and on 14th day was p=0.000 which means there is significant decrease in the number of bacteria colonies. Conclusion: Mouth-rinsing using chlorhexidine gluconate 0.2% significantly affects the amount of plaque-causing bacterial colonies in fixed orthodontic users (p<0.05) with the percentage drop is 61.84%. Keywords: Gargle, Chlorhexidine gluconate 0.2%, Plaque, Fixed orthodontic Cite this Article: Leonarto MN, Habar EH. 2017. The impact of mouth-rinsing using chlorhexidine gluconate 0.2% to the amount of plaque- causing bacteria colonies in fixed orthodontic users. Journal of Dentomaxillofacial Science 1(3): 91-94. DOI: 10.15562/jdmfs.v1i3.320 The impact of mouth-rinsing using chlorhexidine gluconate 0.2% to the amount of plaque-causing bacteria colonies in fixed orthodontic users Melinda N. Leonarto, * Eddy H. Habar Introduction Te percentage of oral health problems has increased from year to year. Tis is evidenced from RISKESDAS 2007 and 2013 by increasing from 23.2% to 25.9%. 1 Te most common oral health problems are tooth decay, periodontal disease and malocclusion. 2 Currently malocclusions are third in the ranking of priorities among the problems of dental public health worldwide, surpassed only by dental cavity and periodontal diseases. 3 Te preva- lence of malocclusion in Indonesia is still very high, approximately about 80% of the population. 4 Te term malocclusion was frst invented by Guilford, it is defned as an abnormality that causes disfgurement or impedes function and requires treatment. Te malocclusion might be associated with one or more of the following: malalignment of individual’s teeth in each arch, malrelationship of the dental arches relative to the normal occlusion: in anteroposterior, vertical, or transverse planes. Occlusion is defned as the manner in which the upper and lower teeth intercuspates with each other in all mandibular positions and movements. It is a result of neuromuscular control of the components of the masticatory system, periodontal structures, maxilla, mandible, temporomandibular joints, and their associated muscles and ligaments. 5 Te orthodontic treatment aims to adjust the position of teeth to the right tooth curve. Tus, efciency of chewing function, face harmony, oral health, dentofacial aesthetics, and tooth position stability can be improved. Te orthodontic treat- ment usually takes 2–3 years. 4 It has been shown that orthodontic treatment induces changes in the oral environment such as an increase in bacterial concentrations like number of mutans: streptococci and lactobacillus spp., alterations in pH, salivary bufering capacity, salivary fow, and dental plaque of these patients. 6–10 Tere is an increase in the volume of dental plaque as well as an increase in the number of bacteria and the concentration of carbo- hydrate in each milligram of plaque. 7 Furthermore, all of these changes are closely associated with hygienic and dietary behavior of the patient. 9 Patients undergoing fxed orthodontic treatment can lead to enamel demineralization, causing white spots, tooth decay and gingivitis. 8 Te number of demineralization injuries increased signifcantly during the frst six months and continued to increase up to 12 months. 9 Te placement of orthodontic appliances increases retention areas and irregular surfaces of brackets and bands provide protec- tion to microorganisms from physical forces. 9–11 Department of Orthodontics, Faculty of Dentistry, Hasanuddin University, Makassar, Indonesia * Correspondence to: Melinda N. Leonarto, Department of Orthodontics, Faculty of Dentistry, Hasanuddin University, Makassar, Indonesia melinda.leonarto@aiesec.net Received: 16 April 2017 Revised: 09 June 2017 Accepted: 21 June 2017 Available Online: 01 August 2017