Effects of cervical headgear and pendulum appliance on vertical dimension in growing subjects: a retrospective controlled clinical trial.

OBJECTIVE To analyze the effects on vertical dentoskeletal dimension produced by cervical headgear (CHG) or Pendulum (P) both followed by full fixed appliances in growing patients with Class II malocclusion. MATERIAL AND METHODS The CHG group (CHGG) consisted of 40 patients (25 females, 15 males) with a mean age of 11.5 years. The P group (PG) comprised 40 patients (21 females, 19 males) with a mean age of 11.6 years. Mean treatment duration with the CHG and P appliances were 1.5 years and 8.2 months, respectively. Lateral cephalograms were available before treatment (T1) and at the end of fixed therapy (T2) with a mean interval of 3.5 years. The effects of the 2 protocols were compared with a matched control group (CG) of 25 untreated Class II subjects (13 females, 12 males). The ANOVA with Tukey's post hoc tests was used to evaluate between-group differences at T1 and during the T1-T2 interval (P < 0.05). RESULTS CHGG showed significantly greater decreases in both Sella-Nasion to A point angle and A-Nasion-B point anglel when compared with both PG (-1.2 and -0.9 degrees, respectively) and CG (-1.9 and -1.5 degrees, respectively). No significant between-group differences were recorded for any of the vertical skeletal measurements. Both CHGG and PG showed significantly greater improvement in molar relationships with respect to CG (+2.5mm). CONCLUSIONS Both distalizing protocols were effective in the correction of Class II malocclusion without increasing the vertical dimension at the end of comprehensive treatment.