Introduction: Early childhood caries (ECC) is the most chronic disease affecting children all over the world. Children often complain of pain and need complete rehabilitation, which is often done under general anesthesia due to extensive treatment and behavioral problems that are often encountered. The present study was undertaken to evaluate the total salivary antioxidant capacity of children with severe ECC (S-ECC) before and after complete dental rehabilitation and compare it with caries-free children. Materials and methods: Salivary samples were obtained from 30 children aged 3–5 years and diagnosed with S-ECC, along with 30 age and sex-matched controls. Complete dental rehabilitation under general anesthesia was performed on the children with S-ECC, and follow-up salivary samples were obtained after 3 and 6 months postoperatively. Total salivary antioxidant capacity was measured using a commercially available Oxygen Radical Absorbance Antioxidant Assay measurement kit. At baseline, children with S-ECC had higher total antioxidant capacity (TAC) compared to the controls. Results: A significant difference in total salivary antioxidant capacity between both groups was seen at baseline. At 3 months following, the total salivary antioxidant capacity of children treated for S-ECC was slightly higher than controls but had significantly reduced compared to baseline. At 6 months, there was no significant difference between both groups. Conclusion: Within the limitations of our study, it can be concluded that the total salivary antioxidant capacity associated with children suffering from S-ECC is reduced after complete rehabilitation.