Slow or rapid palatal expansion for early treatment of unilateral posterior crossbite? Evaluation of the reverse chewing cycles correction.
OBJECTIVE
It is well established that patients with a unilateral posterior crossbite, when chewing on the affected side, show an increased frequency of reverse chewing cycles. It was hypothesized that the correction of reverse cycles may be due to the characteristics of the therapy. The aim was to investigate the prevalence of reverse chewing patterns in children with unilateral posterior crossbite before and after treatment with Function Generating Bite (FGB).


METHODS
Twenty children, (9 boys, 11 girls; age, mean ± SD, 7.5 ± 1.1), 10 with a right and 10 with a left posterior unilateral crossbite were selected. Mandibular movements during chewing soft and hard boluses were measured with a kinesiograph (K7 -I, Myotronics Inc. Tukwila, Washington, USA).


RESULTS
The results showed a significant difference when comparing the percentage of reverse chewing patterns, before and after therapy with FGB, during chewing on the crossbite side both with soft and hard bolus (p<0.0001). No significant differences were observed during chewing on the non-crossbite side.


CONCLUSIONS
The results of this study confirmed that FGB corrects both the dental and functional asymmetries. Knowing that the rapid palatal expansion does not correct the masticatory function, it is of clinical relevance, for the orthodontists, the knowledge and the understanding of the functional outcomes with different therapies.


CONCLUSIONS
The type of treatment and the biomechanics of the appliance used are of great importance for the correction of the reverse chewing cycles and for rebalancing the functional asymmetry of children with unilateral posterior crossbite.
Department of Orthodontics and Gnathology-Masticatory Function, University of Turin, Italy. mariagrazia.piancino@unito.it
Maria G
MG
Piancino
Francesca
F
Talpone
Teresa
T
Vallelonga
Gianluigi
G
Frongia
Cesare L
CL
Debernardi
Pietro
P
Bracco
D001696:Biomechanical Phenomena; D002638:Chewing Gum; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006244:Hardness; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000503:physiopathology / Q000628:therapy*; D008334:Mandible / Q000503:physiopathology; D008409:Mastication / Q000502:physiology*; D009068:Movement; D016382:Orthodontic Appliance Design; D017289:Orthodontic Appliances, Functional; D010155:Palatal Expansion Technique / Q000295:instrumentation
D002638:Chewing Gum