Objective: To compare pain experience between self-ligating and conventional preadjusted edgewise appliance systems with a two-arm parallel trial. Materials and Methods: A prospective multicenter randomized controlled clinical trial was conducted in three hospital orthodontic departments. Subjects were randomly allocated to receive treatment with either a self-ligating (3M SmartClip TM ) or conventional (3M Victory TM ) bracket system with stratification for operator and center. Standardized protocol was followed for bracket bonding procedure and archwire sequence. Subject pain was recorded using a Verbal Rating Scale to assess discomfort felt on the teeth and soft tissues at the time of the appointment and 1, 3, and 5 days after each archwire change up to the working archwire. Multilevel modeling was used to analyze the data by blinded assessors. Results: One hundred thirty-eight subjects (mean age 14 years 11 months) were enrolled in the study, of which 135 subjects (97.8%) completed the study and 113 (82%) returned the required data regarding pain/discomfort. Perceived pain was statistically higher with the SmartClip TM system compared to the Victory TM system, but this difference was not deemed to be clinically significant. Discomfort was greatest after placement of the initial 0.014-inch nickel-titanium archwire, compared with subsequent wires, and was greatest on day 1, less on day 3, and much less on day 5 after each archwire change. Age and gender did not affect the level of discomfort experienced by subjects undergoing fixed appliance treatment. Conclusion: No clinically significant difference in pain experience was found between patients treated with a self-ligating bracket system compared to those treated with a conventional ligation system. (Angle Orthod. 2016;86:149-156.)

There was no clinically significant difference in treatment efficiency between treatment with a self-ligating bracket system and a conventional ligation system.

1. The ovine incisor model presents opportunities to investigate irrigation regimes under controlled ex-vivo conditions. 2.NaOCl (5%) remains the most effective irrigant for rapid debris removal in immature root canals. 3. Carisolv cleans pulp debris from the walls of immature root canals as effectively as NaOCl (1%) during static, unrefreshed wall contact for between 20 and 30 min. 4. Refreshment of NaOCl (1%) enhances its cleaning ability above that of Carisolv.

Ectopic canines are regularly encountered in general dental practice and often fail to be treated by interceptive measures. Ectopic development can easily be monitored during regular dental examinations and early detection can reduce the patient's need for complex and extensive treatment later. Failure to diagnose ectopic canine development appropriately has been the reason for litigation in the past and may increasingly be a risk if practitioners are unable to identify them. A good understanding of canine development, assessment and management is necessary to be able to recognize ectopic development and avoid untoward sequelae.