Tek Taraflı Dudak Damak Yarıklarında Farklı Bölgelerden Ankraj Alan Kemik Destekli Yüz Maskesi Uygulamasının Maksillofasiyal Bölgedeki Etkilerinin Sonlu Elemanlar Analizi İle İncelenmesi

Abstract

Face mask application is a common treatment modality for growing Class III patients with cleft lip and palate and maxillary hypoplasia. The aim of this study was to evaluate the stress distribution and possible amount of movement in the maxillofacial region caused by the change in the maxillary mini-plate application site and the change in the force vector applied for maxillary advancement in an adolescent patient with unilateral cleft lip and palate using finite element analysis. In our study, a three-dimensional model was obtained from a 3D Cone Beam Computed Tomography (CBCT) image of a12-year-old female patient with an operated right unilateral cleft lip and palate who had passed the growth spurt period. Mini-plates were placed in the right and left regions of the maxilla; infrasigomatic crest, premolars and lateral nasal wall in order to provide maxillary advancement force. The forces providing maxillary advancement were applied to the three different models in two different directions, parallel to the occlusal plane (0) and down from the occlusal plane (-), with a magnitude of 500 g bilaterally. The von Mises stress and displacement values of the circummaxillary sutures and nasoalveolar complex were analyzed in the finite element models.Von Mises stress values were higher in 0º force mechanics in all models. In our study, stress values were found to be higher in zygomaticotemporal, zygomaticofrontal and pterygopalatine sutures in all models in all force direction mechanics. In the three main models, maxilla enlargement occurred in the 0º, 500 gr advancement force mechanics with a face mask. The amount of displacement in the sagittal direction was found to be higher in the 0º force mechanics in our three main models, which differed according to the mini-plate placement. Clockwise rotation of the nasomaxillary complex was observed in the -30º force mechanics over the miniplates placed on the lateral nasal wall and between the premolars, while counterclockwise rotation occurred in the other models and force mechanics. In skeletal Class III individuals with unilateral CLP due to maxillary retrognathia, anterior placement of mini-plates in the maxilla may be an alternative when midface advancement and clockwise rotation of the nasomaxillary complex is desired.