The aim of this study was to compare the pulp vitality of primary teeth with deep caries treated with two restorative techniques. The restoration survival rate was also evaluated as a secondary outcome. Children aged from 4 to 8 years with at least one deep carious lesion in molars were selected at the Ibirapuera University dental clinic. One hundred and eight deciduous molars were allocated into two groups: (1) restoration with calcium hydroxide cement lining followed by filling with high-viscosity glass ionomer cement (CHC+HVGIC) or (2) restoration with HVGIC. Pulp vitality and restoration survival were evaluated at 6, 12, and 24 months. Intent-to-treat analysis was used for pulp vitality, and survival analysis was performed with the Kaplan-Meier method (α=5%). Results: At 24 months, 86 restorations were evaluated, and 91 were evaluated at least once during the study. There was no significant difference between the restorative treatments regarding pulp vitality (CHC +HVGIC=70% and HVGIC=68.5%) (OR=1.091; CI95%=0.481-2.475). However, HVGIC (73%) restorations showed a higher survival rate than CHC+HVGIC (50%) (p=0.021). Thus, it can conclude that deep caries in primary molars should be restored with HVGIC, since the technique results in similar pulp vitality to the CHC +HVGIC, but with a higher restoration survival rate.