The objective of this randomized clinical study is to evaluate the survival of repairs in restorations using composite resin (CR) or high viscosity glass ionomer cement (GIC) in primary molars. This trial is nested to another study (NCT03520309), so patients will be enrolled from CARDEC 3. 312 restorations will be included and randomized into two groups: glass ionomer cement (Riva Self Cure, SDI, Australia) and composite resin (Filtek Bulk Fill and Filtek Bulk Fill Flow, 3M ESPE, USA). After the end of treatments, patients will be followed for 24 months to assess the success of the restorations, which will be considered as the absence of the need for reintervention. The Kaplan-Meier survival curves and the log-rank tests will be performed to assess survival between groups and Cox regression analysis will be used to compare the outcome with the variables (α = 5%).

Failed restorations in primary teeth will be repaired using GIC or composite resin.

Inclusion Criteria:

• Children who have sought treatment in the School of Dentistry, University of Sao Paulo
• Children between 3 and 10 years old
• Children presenting at least one restoration (of any material, any surface and any integrity status) in primary teeth

Exclusion Criteria:

• Children whose parents did not agree to participate in the study
• Children with behavioural issues at the initial exam or who did not assent to participate in the study