INTRODUCTION: The aim of this study was to compare the efficiency of mandibular arch alignment in 3 dimensions with a self-ligating bracket system (SmartClip, 3M Unitek, Monrovia, Calif) and a conventional preadjusted edgewise twin bracket (Victory, 3M Unitek) in nonextraction patients. This was a prospective, randomized, controlled clinical trial at the Royal London Hospital, School of Dentistry, and Kent and Canterbury Hospital, United Kingdom. Sixty-six consecutive patients satisfying the inclusion criteria were enrolled in the study. They were randomly allocated with a computer-generated system to 1 of the 2 bracket systems. METHODS: Pretreatment mandibular arch irregularity was measured by using a coordinate measuring machine (Merlin II, International Metrology Systems, Gloucester, United Kingdom). A 0.016-in round martensitic active nickel-titanium aligning archwire (3M Unitek) was placed in all subjects. Mandibular arch irregularity was remeasured 8 weeks later. RESULTS:Sixty-five subjects completed the study. Bracket type had little influence on alignment efficiency overall (P = 0.08), or in the buccal (P = 0.173) or labial segments (P = 0.528) after adjustment for pretreatment differences by analysis of covariance (ANCOVA). Alignment efficiency was highly correlated to pretreatment irregularity overall (P <0.001), both in the buccal (P = 0.001) and labial (P <0.001) segments. Increasing age appeared to have a negative effect on alleviation of irregularity, although this effect did not reach statistical significance (P = 0.053). CONCLUSIONS: The null hypothesis that efficiency of alignment in the mandibular arch in nonextraction patients is independent of bracket type was accepted. Alignment efficiency is largely influenced by initial irregularity.
RCT Entities:
INTRODUCTION: The aim of this study was to compare the efficiency of mandibular arch alignment in 3 dimensions with a self-ligating bracket system (SmartClip, 3M Unitek, Monrovia, Calif) and a conventional preadjusted edgewise twin bracket (Victory, 3M Unitek) in nonextraction patients. This was a prospective, randomized, controlled clinical trial at the Royal London Hospital, School of Dentistry, and Kent and Canterbury Hospital, United Kingdom. Sixty-six consecutive patients satisfying the inclusion criteria were enrolled in the study. They were randomly allocated with a computer-generated system to 1 of the 2 bracket systems. METHODS: Pretreatment mandibular arch irregularity was measured by using a coordinate measuring machine (Merlin II, International Metrology Systems, Gloucester, United Kingdom). A 0.016-in round martensitic active nickel-titanium aligning archwire (3M Unitek) was placed in all subjects. Mandibular arch irregularity was remeasured 8 weeks later. RESULTS: Sixty-five subjects completed the study. Bracket type had little influence on alignment efficiency overall (P = 0.08), or in the buccal (P = 0.173) or labial segments (P = 0.528) after adjustment for pretreatment differences by analysis of covariance (ANCOVA). Alignment efficiency was highly correlated to pretreatment irregularity overall (P <0.001), both in the buccal (P = 0.001) and labial (P <0.001) segments. Increasing age appeared to have a negative effect on alleviation of irregularity, although this effect did not reach statistical significance (P = 0.053). CONCLUSIONS: The null hypothesis that efficiency of alignment in the mandibular arch in nonextraction patients is independent of bracket type was accepted. Alignment efficiency is largely influenced by initial irregularity.
Authors: Andre da C Monini; Luiz G Gandini; Alexandre P Vianna; Renato P Martins; Helder B Jacob Journal: Angle Orthod Date: 2019-02-11 Impact factor: 2.079