BACKGROUND: Bonding is an important step in fixed orthodontic mechanotherapy. Many new materials introduced an adhesive for bonding. This study was designed toevaluate the clinical bond failure rate of orthodontic brackets bonded with green glue: two way color changes adhesive and transbond XT adhesive paste.METHODS: Eighteen male patients with a mean age of 16 years were included in the study. Convenience sampling technique was used to select the sample for this study. The split-mouth design was used to bond 360 brackets by one operator and both adhesives were used in each patient. Bond failure rates were estimated with respect to bonding procedure, dental arch, tooth type (incisor, canine, and premolar). The results were evaluated using the chi-square test. Kaplan – Meier analysis and the log rank test were used to estimate the survival rate of the brackets. Bracket failure rates for each system were analyzed, and failure causes as reported by the patients and the quadrant of each tooth in which brackets failed were recorded.RESULTS: The bond failure rate was 5.00% and 4.44% for green gloo and transbond XT group. No significant difference was found in the bond failure rate between transbond XT and Green gloo group. No significant difference was found in the bond failure rate between the two groups, in relation to right and left side and the type of teeth.CONCLUSION:Green gloo adhesive can be effectively used to bond orthodontic brackets. KEYWORDS: Bond failure rate, adhesive, orthodontic brackets, green gloo, transbondXT.