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Correction of skeletal Class II malocclusion with camouflage orthodontic treatment generally requires the extraction of the maxillary first premolars to provide space for retraction of the maxillary incisors. Retraction of incisors changes the position of the incisors and the dimensions of the dental arch, which can cause changes in tongue posture and affect the upper airway. The purpose of this study was to determine the relationship between premolar extraction on the dimensions of upper airway and tongue posture in skeletal Class II malocclusion. This study was designed as a retrospective cohort using lateral cephalometric radiographs before and after orthodontic treatment. The samples in this study consisted of 44 samples of adult patients (n = 44) aged 18-40 years, who were divided into 2 groups: 22 subjects treated without premolar extraction and 22 subjects treated with premolar extraction. Lateral cephalometric radiographic analysis were used to measure the dimensions of the upper airway by analyzing superior posterior airway space (SPAS), middle airway space (MAS), inferior airway space (IAS), vertical airway length (VAL), and tongue posture (tongue length and height tongue) using imageJ software. No Statistically significant different changes were observed as seen from the following results: SPAS (p = 0.709), MAS (p = 0.365), IAS (p = 0.562), (p = 0.401), tongue length (p = 0.578), tongue height (p = 0.086) in the sample group without extraction premolar. No significant alterations in the upper airway and tongue posture measurement were observed in the sample group with extraction premolar. Premolar extraction with retraction on upper incisors did not affect upper airway dimensions and toung posture in skeletal Class II malocclusion.

Background The aim of the study was to analyze the morphology and position of the tongue and hyoid bone in skeletal Class II patients with different vertical growth patterns by cone beam computed tomography in comparison to skeletal Class I patients. Methods Ninety subjects with malocclusion were divided into skeletal Class II and Class I groups by ANB angles. Based on different vertical growth patterns, subjects in each group were divided into 3 subgroups: high-angle group (MP-FH ≥ 32.0°), average-angle group (22.0° ≤ MP-FH t‐test was used to compare the position and morphology of the tongue and hyoid bone between skeletal Class I and Class II groups. One-way analysis of variance (ANOVA) was used to compare the measurement indexes of different vertical facial patterns in each group. Results Patients in skeletal Class II group had lower tongue posture, and the tongue body was smaller than that of those in the Class I group (P P P P > 0.05). Conclusion Patients with skeletal Class II malocclusion have lower tongue posture, a smaller tongue body, and greater occurrence of posterior inferior hyoid bone position than skeletal Class I patients. The length of the mandibular body in skeletal Class I patients with a horizontal growth type is longer. The position and morphology of the tongue and hyoid bone were not greatly affected by vertical facial development in skeletal Class II patients.

A 45-year-old woman presented with an anterior open-bite complaining chiefly of her unpleasant smile esthetics and masticatory and speech problems. Treatment included speech therapy initiated immediately after bonding. Lingual spurs were positioned on the mandibular incisors in order to help tongue rehabilitation. During the working phase, temporary anchorage devices (TADs) were used at the mandibular anterior segment to intrude the lower left premolars. A splint was used to ensure retention in the upper and lower arches; an enveloppe linguale nocturne (ELN) was provided. Non-surgical open-bite treatment could offer a valid alternative to orthognanthic surgery when cephalometric evaluation shows no vertical growth pattern; patient compliance is essential to prevent relapse.

Twelve young adults in a good general health were observed during habitual posture of tongue and jaw in different emotional conditions induced by watching three video sequences. The position of the mandible was tracked by the displacements of an electromagnetic sensor glued to the chin. The tongue-to-palate distance was obtained by 2-D location of three electromagnetic sensors placed on the tongue upper midline surface. Head displacements were evaluated with a sensor fixed to an upper central incisor and were subtracted from corresponding displacements of tongue and chin sensors to obtain the real tongue and mandible positions during continuous recording sequences. Emotional conditioning by a fear movie influenced the vertical position of the mandible: the mean interarch distances during the fear movie (2 center dot 34 +/- 0 center dot 24mm) were significantly different from those measured during the tender (3 center dot 13 +/- 0 center dot 35) and neutral (3 center dot 42 +/- 0 center dot 80) movies, respectively (anova repeated measure, SNK; P

The use of self-ligating brackets has gained popularity recently in orthodontic treatment. The Damon philosophy is a system that employs passive self-ligation with the use of light forces to achieve arch development and to relieve dental crowding. The philosophy of the system is that the use of light forces does not overpower the forces of the lips, tongue, and other peri-oral soft tissue thereby allowing for optimal equilibration of forces that is customized to every individual. If this actually occurs, changes in the posture of the tongue and hyoid would be expected as is seen after orthognathic surgery and rapid maxillary expansion. The purpose of this study was to evaluate if these postural adjustments do occur, and, if they do, to assess if there is a stratification of treatment effect based on dental classification. A customized cephalometric evaluation was designed from an amalgamation of previous cephalometric studies. This cephalometric study not only evaluated changes due to treatment but also assessed changes in cervical postural position to validate the quality of the measurements and to verify that radiographs were taken in a correct and repeatable head position. Cephalometric measurements were correlated with measurements of posterior dental expansion at the premolars and molars. Results of the study showed a correlation in tongue length and hyoid to mandible measurements. Lack of significance in the cervical posture cephalometric changes validated the cephalometric design and the quality of radiograph included in the study. Significant posterior dental expansion was documented although this expansion was limited to the premolar regions. Changes in tongue length correlated with dental expansion, particularly in the lower premolars. Lastly, increases in upper airway space correlated with dental expansion, particularly in Class III patients. This finding is very interesting and suggests the need for further research in this area. Additionally, replication of this study with more subjects may yield very interesting results. Overall, this study supports the fact that studies of soft tissue changes in relation to orthodontic treatment need further investigation as these tissues are involved in the equilibrium of forces and are directly related to the stability of orthodontic treatment.