Introduction: The aim of this study was to compare 2 types of treatment for Class II malocclusion. One treatment required compliance by the patients, the other did not.
Methods: The sample consisted of 60 children who were treated with either conventional cervical headgear combined with full fixed appliances (n = 30), or with a pendulum appliance followed by full fixed appliances (n = 30). At the start of treatment, the mean ages were 11 years 7 months for the headgear group and 11 years 6 months for the pendulum group. The total active treatment time was recorded for all patients, and lateral cephalograms were taken before treatment and after fixed appliance therapy. Angular, horizontal, and vertical changes were recorded to monitor the skeletal and dentoalveolar changes. The lengths of active treatment, the differences between the pretreatment and posttreatment data in both groups, and the differences in the therapeutic effects between the 2 groups were analyzed with the Student t test. The Pearson r correlation coefficient was applied to determine factors affecting the length of active treatment.
Results and conclusions: Class II correction with headgear had more skeletal effect than with the pendulum. SNA angle reductions were 1.3 degrees in the headgear group and 0.3 degrees in the pendulum group The difference (1.0 degrees , P <.01) was significant. SNPg was not affected by either therapy and increased slightly. ANPg was also more reduced in the headgear group (difference 1.5 degrees , P <.005). Forward movement of ANS was more restricted in the headgear group (difference 1.6 mm, P <.05). No significant difference was found in molar extrusion between both types of treatment. The duration of active treatment was longer in the group that used the pendulum as the first phase (P <.005). The 4.6-month difference corresponded approximately to the length of pendulum wear (5.6 months).