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Updated: May 22, 2026
A Postoperative Evaluation Guideline for Computer-Assisted Reconstruction of the Mandible
Published on: January 28, 2020
Study of mandibular growth in patients treated with Fränkel's functional regulator (1b)
Juan-Jose Alió-Sanz1, Eyleen Kato, Jose Lorenzo-Pernía
1Complutense University of Madrid, Facultad de Odontología, Plaza Ramón y Cajal s/n, 28040 Madrid, Spain. jjaliosa@odon.ucm.es
Objectives:
The purpose of this study was to assess mandibular growth in patients with Class II division 1 malocclusions when treated with Fränkel's functional regulator 1b.
Study Design:
The treatment group was made up of 43 patients that were divided into two groups: prepubescent (n:28), and pubescent (n:15). The control group included 40 patients who did not receive any kind of treatment and were likewise divided into a prepubescent group (n:19), and a pubescent group (n:21). A computerized cephalometric study was carried out and superimpositions were done in order to assess the antero-posterior, vertical and rotational movements of the mandible. A two-way ANOVA with interaction was done to compare the changes between the control group and the treatment group, while the Student t for independent samples was used to compare each age group.
Results:
The Gnathion and Gonion points showed significant differences in the whole sample (p<0.001) as well as in the prepubescent (p<0.001) and pubescent groups (p<0.05). Rotational changes of the mandible measured using the facial axis and mandibular plane showed no statistical differences between both groups (p>0.05).
Conclusion:
The results show that the FR produces vertical orthopedic growth in the mandible but not horizontal growth compared to non-treated Class II-type I malocclusion patients. No rotational changes were found in the mandible, but we did record mandibular growth along the inclination of the facial axis.
