Stability of class II treatment with Pendulum and Jones jig followed by fixed appliances

Introduction: The present study aimed to evaluate and compare the long-term stability of Class II correction with the Pendulum or Jones jig followed by fixed appliances.

Settings and sample population: Group 1 comprised 20 Class II malocclusion patients with a mean initial age of 13.97 years (SD = 1.57), treated with Pendulum and fixed appliances for a mean period of 4.72 years (SD = 0.98), and mean long-term post-treatment evaluation of 4.72 years (SD = 0.97). Group 2 consisted of 18 Class II patients with a mean initial age of 13.19 years (SD = 1.26), treated with Jones jig and fixed appliances for a mean period of 3.96 years (SD = 0.92). Mean long-term post-treatment time was 5.50 years (SD = 1.57).

Methods: Lateral cephalograms were evaluated at three stages: initial (T1), final (T2) and long-term post-treatment (T3). Intragroup comparisons were performed with repeated measures ANOVA and Tukey's test and intergroup comparisons with independent t test.

Results: Many treatment changes were observed in both groups. From the long-term post-treatment periods, there was stability for most of the variables. Maxillary second molars and mandibular first molars extruded in the Jones jig group and slightly intruded in the Pendulum appliance group. The nasolabial angle decreased in the Pendulum group and increased in the Jones jig group.

Conclusion: The correction of a Class II malocclusion was shown to be stable with similar long-term post-treatment results with Pendulum or Jones jig followed by fixed orthodontic appliances.