Skip to main content

Table 3 Mixed ANOVA interaction effect

From: A two-year comparative assessment of retention of arch width increases between modified vacuum-formed and Hawley retainers: a multi-center randomized clinical trial

Variable Time interval HR group 95% confidence interval mVFR group 95% confidence interval Mixed ANOVA P value (Interaction effect)
Mean ± SD (mm) Mean ± SD (mm)
ICW       .83
T0 37.20 ± 2.46 36.09–38.30 38.04 ± 2.00 36.97–39.12  
T1 37.19 ± 2.55 36.05–38.32 37.93 ± 2.02 36.83–39.03  
T2 37.07 ± 2.53 35.96–38.17 37.80 ± 1.92 36.73–38.87  
T3 36.80 ± 2.78 35.61–37.99 37.55 ± 1.99 36.40–38.70  
T4 36.90 ± 2.65 35.76–38.04 37.65 ± 1.93 36.54–38.76  
IPMW       .63
T0 45.39 ± 1.88 44.33–46.45 47.10 ± 1.84 46.04–48.17  
T1 45.37 ± 1.88 44.29–46.46 46.87 ± 1.92 45.79–47.96  
T2 45.26 ± 1.94 44.10–46.41 46.77 ± 2.08 45.62–47.92  
T3 44.80 ± 1.92 43.62–45.97 46.40 ± 2.17 45.22–47.57  
T4 44.61 ± 2.13 43.39–45.82 46.31 ± 2.12 45.09–47.52  
IFMW1       .22
T0 51.16 ± 1.73 50.12–52.21 53.35 ± 2.29 52.37–54.33  
T1 51.31 ± 1.66 50.27–52.36 53.15 ± 2.35 52.17–54.14  
T2 51.16 ± 1.79 50.07–52.26 53.01 ± 2.43 51.97–54.04  
T3 50.88 ± 1.82 49.78–51.98 52.93 ± 2.42 51.89–53.97  
T4 50.74 ± 2.00 49.64–51.85 52.86 ± 2.31 51.82–53.90  
IFMW2       .46
T0 52.34 ± 2.09 51.14–53.54 54.26 ± 2.56 53.13–55.39  
T1 52.50 ± 2.16 51.24–53.75 54.20 ± 2.71 53.02–55.38  
T2 52.27 ± 2.15 51.00–53.54 54.11 ± 2.75 52.91–55.30  
T3 52.09 ± 2.29 50.80–53.39 53.96 ± 2.75 52.73–55.18  
T4 52.04 ± 2.21 50.78–53.31 54.05 ± 2.71 52.86–55.25  
  1. HR indicates Hawley retainer; mVFR, modified vacuum-formed retainer; SD, standard deviation; ICW, intercanine width; IPMW, interpremolar width; IFMW1, interfirst molar mesiobuccal cusp width-; IFMW2, interfirst molar distobuccal cusp width; T0, at debond; T1, 3-month retention; T2, 6-month retention; T3, 12-month retention; T4, 24-month retention