Treatment of Unilateral Posterior Cross Bite in Children

Rapid maxillary expansion and quad-helix are two well established appliances in dentistry used for posterior cross bite treatment. This study aims to compare this two different appliances in patients in their early mixed dentition, regarding treatment effects of the extra oral soft tissue but also dental and skeletal effects, if the children experience any pain and discomfort during treatment and the study also aims to make a cost minimization analysis. Comparison of these different treatments are barely made and no randomized controlled trial is yet published. No study has evaluated the difference of subjective experience during these two treatments. After this study we will know which one of these two appliances are the most effective, regarding cost minimization and treatment result but we are also able to put it in relation to the patients subjective experience

Skeletal expansion evaluated by computed tomography at three time points in both arms. The change in width of the palatal median suture is going to be evaluated and compared to the Baseline values, in both arms.

Dental effects and side effects evaluated by computed tomography at three time points in both arms.The change in degree of angulation and inclination of the dental structures (e.g. tooth inclinations) is going to be evaluated and compared to the Baseline values, in both arms.

Questionnaire The Questionnaire has some questions with Visual Analogue Scale. With the minimum value of "0" and maximum value of "10". Higher values mean worse outcome. Other questions in the questionnaire have a "yes" and "No" nature.

Evaluation of both the direct and indirect costs of the treatment, number of emergency visits, treatment duration (in total) etc are going to be evaluated.

Inclusion Criteria: Children in the early mixed dentition Unilateral posterior cross bite including the first permanent molar Exclusion Criteria: No ongoing sucking habits Craniofacial syndroms Earlier Orthodontic treatments Not able to independently understand and answer the questionnaires

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Hansson S, Josefsson E, Lindsten R, Magnuson A, Bazargani F. Pain and discomfort during the first week of maxillary expansion using two different expanders: patient-reported outcomes in a randomized controlled trial. Eur J Orthod. 2023 May 31;45(3):271-280. doi: 10.1093/ejo/cjac067.