Methodology: Thirty-six decayed primary molars (class 1) without pulp exposure and the depth of dental caries not more than the coronal two thirds of the crown . The treated children aged between 4-7 years. The children were randomly divided into three equal groups. The total time of caries removal in each tooth were calculated using stopwatch and mean time of each method was obtained. Also the physical pain was assessed by asking the children to choose the face that express their condition and feeling using Wong-Baker FACES analysis scale. The children were recalled for clinical and radiographic evaluation at certain intervals (pre-operative, 1m and 6m post-operative). The collected data were tabulated and statistically analyzed.
Results: The conventional method showed the shortest time (2.82±0.477 min.) of caries removal followed by Brix 3000 (5.47±1.35 min.) and 2.25% sodium hypochlorite gel (7.24±1.45 min.). In regard to pain sensation assessment the conventional method showed the highest grade of pain sensation with high significant differences to the two other chemomechanical methods of caries removal. At the same time; the results showed no statistically significant difference between 2.25% sodium hypochlorite gel and Brix 3000. The clinical and radiographic evaluation showed that there was no statistically significant difference after one month or six months between the conventional methods, 2.25% sodium hypochlorite gel and Brix 3000. The success rate among these groups showed that there was no statistically significant difference between the success rates of all groups of this study.