Background No previous trial (randomized and controlled) studied the levels of pain, discomfort, and acceptability associated with acceleration of dental movement during orthodontic treatment using corticision. The purpose of this study is to compare the pain, discomfort, ease of procedure, patient satisfaction, and analgesic use during corticision-assisted (without extraction) decrowding of the lower anterior teeth with the traditional orthodontic method. Materials and Methods Fifty-two patients (38 females, 14 males; mean age: 21.38 ± 1.05) were randomly distributed into two groups: the corticision group (CORT, n=26) and the control group (CONT, n=26). Corticision was applied by a surgical blade and a hammer at three anterior regions on the lower jaw using three radiological guides. The levels of pain, discomfort, swelling and chewing difficulties were registered on a visual analog scale (VAS) at one, seven, and 14 days after applying the first wire (0.14-inch NiTi archwire). Questionnaires were administered to assess the level of satisfaction, ease of the procedure, and the number of analgesics patients took. Mann-Whitney U tests were used to detect significant differences between the two groups. The Chi-Square test was used to study the significance of differences in taking analgesics during the first week of treatment. Results One day following the intervention, there were no statistically significant differences between the two groups concerning pain levels, discomfort, and difficulties of mastication (P=0.293, P=0.166, P=0.538; respectively), but there was a statistically significant difference in the perceived swelling (P=0.012). On the seventh and 14th days of assessment, there were no statistically significant differences between the two groups regarding the previous variables. In the CORT group, the proportion of patients who were satisfied with treatment was approximately 94%, the proportion of those who found the treatment easy was 96%, 84% of patients wanted to repeat the procedure, and 92% of them would recommend this procedure to a friend. Conclusions There were no statistically significant differences in pain perception, discomfort, difficulties with mastication, and analgesic consumption between the interventional group and the control group. The perception of swelling was greater in the experiment group (the corticision group) at 24 hours following the first archwire engagement, and then it gradually decreased. Patients in both groups showed high levels of satisfaction following leveling and alignment. Those in the experimental groups showed a high level of willingness to undergo the same procedure again and a high level to recommend this procedure to a friend.