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Abstract
Introduction: In spite of the controversy, several studies associate the malocclusions framed in different skeletal classes with the alterations caused by the craniocervical posture. Accordingly, the performance of interceptive orthodontic treatment in the paediatric population can prevent posture complications. Therefore, we should consider the stomatognathic system as a biomechanical unit.
Objectives: Evaluate comparatively the craniocervical posture in patients with skeletal class II in mixed dentition phase, treated with headgear-activator Teuscher appliance engaged with extraoral forces of occipital traction, before and after the interceptive orthodontic treatment.
Material and Methods: The sample comprised 24 individuals, composed of 13 elements of the female gender (54.2%) and 11 elements of the male gender. The data was obtained at two time points – T0 and T1. T0 corresponds to the period just before the interceptive orthodontic treatment began, whereas T1 corresponds to the period immediately after the cessation of such treatment.
The individual’s ages at the considered time points ranged from 7.9 to 12.3 and from 10.1 to 15.2 for T0 and T1, respectively. Thus, on average, the second evaluation (T1) was performed 2.8 years after the first (T0). The cephalometric analyses correspondent to T0 and T1 of each patient were performed consulting selected parameters of previous analyses performed by Ricketts, Steiner, Rocabado, Solow and Tallgren. The obtained data was statistically analysed resorting to the Shapiro-Wilk test, T-Student test for paired and independent sampling and the Interclass Correlation Coefficient (significance level of 5%).
Results: The results of this study don’t reveal a relationship between skeletal class II malocclusion in the mixed dentition phase with craniocervical posture, although the differences are close to statistical significance, relatively to the averages of the Facial Axis (decreased from 86,63º to 85.63º – p = 0.064), the Mandibular Arch (increased from 29.25º to 30.75º – p = 0.056) and the OPT/HOR Angle decreased from 90.63º to 87.29º – p = 0.056). Between the female and male gender patients, the only statistically significant difference (p = 0.005) between the two time points was observed in the Mandibular Arch. Herein, an average increase of 3.31º on female gender patients was registered, whereas in the male gender, an average decrease of 0.64º was detected.
Conclusion: No statistically significant differences were observed in the craniocervical posture before and after the application of headgear-activator Teuscher appliance engaged with extra-oral forces of occipital traction. However, the OPT/HOR angle presents an average difference close to statistical significance, which indicates that the cervical spine tends to incline more to the anterior direction in relation to the line True Horizontal, after the interceptive orthodontic treatment.
Female gender patients presented statistically significant differences on the Mandibular Arch, which represents the tendency for horizontal growth in the mandible.
Key-words: “Craniocervical Posture”, “Skeletal Class II”, “Headgear-activator Teuscher appliance”, “Mixed Dentition” and “Natural Head Position”