Renato Bigliazzi1, Lorenzo Franchi2, André Pinheiro de Magalhães Bertoz3, James A McNamara4, Kurt Faltin5, Francisco Antonio Bertoz6. 1. a PhD Candidate in Orthodontics, Department of Pediatric and Social Dentistry, Dental School of Araçatuba, Universidade Estadual Paulista, São Paulo, Brazil, and Adjunct Professor, Department of Orthodontics, School of Dentistry, University Paulista, Araçatuba, São Paulo, Brazil. 2. b Assistant Professor, Department of Surgery and Translational Medicine, University of Florence, Florence, Italy, and Thomas M. Graber Visiting Scholar, Department of Orthodontics and Pediatric Dentistry, School of Dentistry, The University of Michigan, Ann Arbor, Mich. 3. c Assistant Professor, Department of Pediatric and Social Dentistry, Dental School of Araçatuba, Universidade Estadual Paulista, São Paulo, Brazil. 4. d Thomas M. and Doris Graber Endowed Professor of Dentistry, Department of Orthodontics and Pediatric Dentistry, School of Dentistry; Professor of Cell and Developmental Biology, School of Medicine; Research Professor, Center for Human Growth and Development, The University of Michigan, Ann Arbor, and private practice, Ann Arbor, Mich. 5. e Professor and Department Chair, Department of Orthodontics, School of Dentistry, University Paulista, Araçatuba, São Paulo, Brazil. 6. f Professor, Department of Pediatric and Social Dentistry, Dental School of Araçatuba, Universidade Estadual Paulista, São Paulo, Brazil.
Abstract
OBJECTIVE: To evaluate the long-term effects of the standard (Class II) Balters bionator in growing patients with Class II malocclusion with mandibular retrusion by using morphometrics (thin-plate spline [TPS] analysis). MATERIALS AND METHODS: Twenty-three Class II patients (8 male, 15 female) were treated consecutively with the Balters bionator (bionator group). The sample was evaluated at T0, start of treatment; T1, end of bionator therapy; and T2, long-term observation (including fixed appliances). Mean age at the start of treatment was 10 years 2 months (T0); at posttreatment, 12 years 3 months (T1); and at long-term follow-up, 18 years 2 months (T2). The control group consisted of 22 subjects (11 male, 11 female) with untreated Class II malocclusion. Lateral cephalograms were analyzed at the three time points for all groups. TPS analysis evaluated statistical differences (permutation tests) in the craniofacial shape and size between the bionator and control groups. RESULTS: TPS analysis showed that treatment with the bionator is able to produce favorable mandibular shape changes (forward and downward displacement) that contribute significantly to the correction of the Class II dentoskeletal imbalance. These results are maintained at a long-term observation after completion of growth. The control group showed no statistically significant differences in the correction of Class II malocclusion. CONCLUSIONS: This study suggests that bionator treatment of Class II malocclusion produces favorable results over the long term with a combination of skeletal and dentoalveolar shape changes.
OBJECTIVE: To evaluate the long-term effects of the standard (Class II) Balters bionator in growing patients with Class II malocclusion with mandibular retrusion by using morphometrics (thin-plate spline [TPS] analysis). MATERIALS AND METHODS: Twenty-three Class II patients (8 male, 15 female) were treated consecutively with the Balters bionator (bionator group). The sample was evaluated at T0, start of treatment; T1, end of bionator therapy; and T2, long-term observation (including fixed appliances). Mean age at the start of treatment was 10 years 2 months (T0); at posttreatment, 12 years 3 months (T1); and at long-term follow-up, 18 years 2 months (T2). The control group consisted of 22 subjects (11 male, 11 female) with untreated Class II malocclusion. Lateral cephalograms were analyzed at the three time points for all groups. TPS analysis evaluated statistical differences (permutation tests) in the craniofacial shape and size between the bionator and control groups. RESULTS: TPS analysis showed that treatment with the bionator is able to produce favorable mandibular shape changes (forward and downward displacement) that contribute significantly to the correction of the Class II dentoskeletal imbalance. These results are maintained at a long-term observation after completion of growth. The control group showed no statistically significant differences in the correction of Class II malocclusion. CONCLUSIONS: This study suggests that bionator treatment of Class II malocclusion produces favorable results over the long term with a combination of skeletal and dentoalveolar shape changes.
Entities:
Keywords:
Class II malocclusion; Functional jaw orthopedics; Morphometric analysis; Thin-plate spline analysis
Authors: Francesca Gazzani; Antonio Carlos de Oliveira Ruellas; Kurt Faltin; Lorenzo Franchi; Paola Cozza; Renato Bigliazzi; Lucia Helena Soares Cevidanes; Roberta Lione Journal: Biomed Res Int Date: 2018-04-24 Impact factor: 3.411