Objective: The aim of this study was to assess the influence of heated in the clinical success of proximal high viscosity glass ionomer cement (GIC) restorations in primary molars.

Material & Method: This randomized, split mouth, multicenter study was performed in four different centers including 88 patients aged between 5-7 years old. Selection criteria included clinically and/or radiographically detected proximal caries extending into the dentin tissue. A total of 250 primary molars were restored with a bulk fill GIC (Equia Forte, GC, Europe) and randomly allocated to one of the following groups: 1) non-heated (n = 125) and 2) heated (n = 125). LED light (GC- D-Light DUO, Tokyo Japan) was used at standard mode 1200 mW/cm2, at 50-60 ºC, for 60 sec for heat application. All restorations were clinically evaluated using modified USPHS criteria at the baseline, 6 months and 12 months. Chi-square test, Fisher's Exact Chi-square test, Continuity (Yates) correction, Fisher Freeman Halton test and Mc Nemar test were used to compare qualitative data with descriptive statistical methods (frequency). Kaplan Meier and Life Tables were used for survival analysis. P value < 0.05 was considered statistically significant.

Inclusion Criteria:

• Subject is mentally and systemically healthy
• Subject has at least two approximal carious lesions at both sides of jaws
• Subject has a normal occlusal relationship with natural dentition
• Subject has at least one adjacent tooth contact

Exclusion Criteria:

• Subject has history of bruxism,
• Subject has allergies to ingredients of glass ionomer based restorative materials.
• Cavity/Caries has highly mineralized pigmented lesions, hypoplasia, fracture or cracks,
• Subject has abrasion, erosion, abfraction,
• Subject has fistula, abscess or pathological mobility,
• Subject has pain, pulp exposure