Introduction: Early tooth loss in young patients can provide undesired tooth movement, decreased length of arches, change in the eruption sequence of the permanent teeth, inadequate development of mastication, swallowing, deleterious habits, speech alterations, midline deviation that can possibly lead to facial asymmetries. Guidelines of the American Academy of Odontopediatrics claim that the use of space maintaining appliances is indicated to avoid loss of arch perimeter, maintaining the relative position of the existing teeth, the healthy devellopment of the facial muscles and the normal establishment of the definitive occlusion. Objectives: This study has the aim to demonstrate the clinical case of a young patient with premature loss of deciduous teeth. This way, we opted to use a removable space maintainer (with teeth and a screw). Clinical Case- Diagnosis: Six-year-old child with multiple caries; with associated fistula on teeth 51, 75 and 84; midline deviation; mouth breathing, tongue interposition and child swallowing disorder. Treatment procedures: Extraction teeth 51, 75, 84 e 85; multiple restorations; Inferior removable space maintainer with a vestibular arch and an middle expansion screw. Discussion: Removable appliances are indicated in the absence of multiple teeth, they can be designed with acrylic teeth to replace edentulous spaces and some type of retention system. Results: The mandibular removable appliance is for certain an important technique in maintaining the tooth space, restore physiological mastication and a good phonation. It's a functional appliance with a good patient compliance which was confirmed with a two months of follow-up. Palabras clave: premature tooth loss, space loss, space maintainer, tooth migration