This will be a randomized, controlled, parallel-group clinical trial. The aim of this studio will be to evaluate the effectiveness of "Hands/Eyes/mouth" behavior management technique versus a conventional technique (covering the patient´s vision) during an inferior alveolar and lingual nerve block in preschool children referred for treatment at the School of Dentistry, Cardenal Herrera CEU University (Valencia, Spain). The sample will consist of 52 children from 3 years old to 5 years 11 months old who need dental pulp treatment and/or tooth extraction of primary molars. Preschool children with no history of allergies to Lidocaine or systemic/neurological diseases and who did not take local anesthesia before the study will be include in this research.