A 2-year-old child received a dental trauma. Objectively the crowns of 51 and 61 are shorter than the crowns of adjacent teeth by 1/3. Mucosa in the area of 51 and 61 is hyperemic and swollen. X- ray shows no periodontal fissure in the apical area of the roots of 51 and 61. What treatment tactics would be optimal in this case?