3D Comparison of Mandibular Response to Functional Appliances: Balters Bionator versus Sander Bite Jumping

Abstract

Aim To assess the three-dimensional (3D) maxillomandibular and dental response to Balters Bionator (BB) and the Sander Bite Jumping Appliance (SBJA) in growing patients. Materials and Methods Twenty-seven Class II division 1 patients (13 males, 14 females), consecutively treated with either the BB (9 females, 7 males; 10.1 ± 1.6 years) or SBJA (5 females, 6 males; 11 ± 1.9 years), were collected from a single orthodontic practice. All patients presented overjet ≥5 mm, full Class II or end-to-end molar relationship, mandibular retrusion. CBCT scans were available at T1 and after removal of the functional appliances (T2) with a mean interval of 18 months. The 3D location and direction of skeletal and dental changes with growth and treatment were quantitatively assessed. Statistical analysis was performed by means of Mann–Whitney U test (p < 0.05). Results Patients treated with the SBJA and BB orthopedic appliances presented, respectively, 4.7 mm and 4.5 mm of 3D displacement of the chin, with marked ramus growth of, respectively, 3.7 mm and 2.3 mm. While the mandible and maxilla grew downward and forward, no opening of the mandible plane was observed. Both appliances adequately controlled labial inclination of lower incisors (1.3° and 0.3°, for the SBJA and BB groups, resp.). No significant between-group differences were found for the T2−T1 changes for any of the variables, with the exception of molar displacements (significantly greater in the SBJA group than in the BB group, 1.2 mm and 0.9 mm, resp.). Conclusions The maxillomandibular and dental growth responses to BB and SBJA therapies are characterized by vertical ramus growth and elongation of mandible that improve the maxillomandibular relationship with adequate control of lower incisor position.

Different approaches to the treatment of skeletal Class II malocclusion during growth: Bionator versus extraoral appliance

“…Studies using CT scans found an increase in airflow in the oropharynx of patients with skeletal Class II malocclusion treated with functional appliances 21,23 . These appliances seem to keep the tongue in a more advanced position, which indirectly increases posterior airflow space 21 .…”

“…The objective of the treatment was to correct the skeletal Class II and Angle Class II division 1 malocclusion. In the first stage, a removable protraction appliance, the Balters Bionator 22,23 , was indicated to stimulate mandibular growth. It should be used all the time, except in the first month, when it should be removed for school activities, for speech adaptation.…”

“…The Bionator, developed by Wilhelm Balters in the 1950s, is a removable functional orthopedic activator that acts on both the orofacial muscle positioning and the primary anterior displacement of the mandible. It is used to correct Class II malocclusion by means of stimulation or acceleration of mandibular growth, combined with maxillary growth restriction and anterior displacement [22][23][24] . In addition, maxillary incisors are retroclined, the mandibular incisors, proclined, overjet is reduced and the Angle Class II molar relationship is corrected 17,20,23,24 .…”

“…It is used to correct Class II malocclusion by means of stimulation or acceleration of mandibular growth, combined with maxillary growth restriction and anterior displacement [22][23][24] . In addition, maxillary incisors are retroclined, the mandibular incisors, proclined, overjet is reduced and the Angle Class II molar relationship is corrected 17,20,23,24 .…”

Three-dimensional cone beam computed tomography analysis of temporomandibular joint response to the Twin-block functional appliance

“…These results were in agreement with those reported in the CBCT study by Gazzani et al and others. [31][32][33] The current retrospective study provides a 3D analysis method for the clinical evaluation of TMJ changes. This method has good clinical application prospects for yielding higher accuracy.…”