A prospective randomized trial investigating lower incisor inclination and mandibular arch dimensional changes of two pre-adjusted edgewise orthodontic bracket systems in non-extraction cases

INTERVENTION: Smart‐Clip® ligature free brackets vs conventional pre‐adjusted edgewise brackets (3M Unitek). CONDITION: Oral Health: Orthodontics ; Oral Health ; Orthodontics PRIMARY OUTCOME: The ability of two fixed appliance orthodontic bracket systems to align crowded lower incisors. In particular lower incisor inclination and arch form changes will be compared.; Null hypothesis: there is no difference in lower incisor inclination, and angulation, and lower arch dimensions using self‐ligating and conventional pre‐adjusted edgewise brackets. SECONDARY OUTCOME: No secondary outcome measures INCLUSION CRITERIA: 1. Patients should be fit and well and not currently on any medication or suffering from any craniofacial syndrome. Medication could theoretically affect the connective tissues that remodel during orthodontic treatment 2. Children under 18 years 3. Lower incisor tooth crowding of up to 5mm as part of their malocclusion 4. A requirement for fixed orthodontic treatment on a non‐extraction basis 5. More severely crowded dentitions often require the loss of premolar teeth to provide the necessary space for alignment of the dental arch