CORINA CIUPILAN, MARIUS VALERIU HINGANU, DELIA HINGANU, OANA ELENA CIURCANU, MIHAELA MONICA SCUTARIU STUDY OF THE OCCURANCE OF LABIO-PALATINE CLEFT EMBRYOGENIC DISORDERS OF THE STOMATOGNATED SYSTEM BY USING LOTS OF WISTAR RATS FEMALES Labio-maxilo-palatine clefts are embryogenesis disorders of the stomatognathic system that occur due to the action of genetic or non-genetic factors in weeks 5-6 of intrauterine life. The clefts are part of the group of congenital malformations of the face. They appear from birth as a slit in the upper lip, hard palate and/or soft palate.Labio-maxilo-palatine cleafts are a current medical problem, especially regarding surgical recovery; they are congenital malformations of the face characterized by the absence of substance in the upper lip and/or in the palatine vault caused by the lack of fusion of labial and / or palatine buds during embryonic development.Simple labial cleft concerns only the lip, unlike the complete labial cleft which affects also the alveolar maxillary arch. In the case of this malformation, more serious than labial cleft, the cleft also affects the bone structures (the alveolar maxillary arche, the buccal palate) so that the oral cavity communicates with the nasal cavity and prevents sucking in infants. An early surgical recovery restores the integrity of anatomical structures, reestablishes disturbed functions, creates favorable conditions for speech education and social adaptation of the child according to age.The procedure is applied prior to the primary suture of the lip and of the anterior palate in order to minimize the dislocation of the segments of the maxillary arch. The correction of the malformation of the jaw arch in the case of bilateral clefts is much more difficult, but it has a greater importance due to the difficulty of reconstruction of the muscular plan and severe deformations, what will persist if the segments can not be aligned.In the bilateral clefts, the lateral segments are displaced medially, and the medial segment is protruding. The purpose of preoperative orthodontic treatment is to reposition the lateral segments so that the medial segment can be coaxed between them together as a vault key of the maxillary arch. In order to study the occurrence of labio-palatine cleft, we used eight groups of Wistar females rat, weighing between 200 and 250 grams. Each sample consists of 10 females rats. Most of the labial and palatine clefts are the result of multiple, genetic and non-genetic factors, each producing a minor developmental defect, called multifactorial heritage;It can be represented by a model in which responsibility for a disease is a variable caused by a combination of genetic and environmental factors. The therapeutic outcome depends on the complexity of the malformation, on the moment of surgery and on the selection of the most modern techniques and equipment suitable for the patient.