The aim of this study is to determine the optimal combination of self-curing resins and type of matrix that provides a minimal temperature increase in the pulp chamber during the fabrication of temporary crowns. Material and methods. We designed as experimental model of direct temporary crown fabrication for extracted and than prepared molars. Intrapulpal temperature rise was measured in vitro conditions during polymerization of Protemp II (3M), Protemp 4 (3M), Visalis Temp (Kettenbach), Structur (Voco) and Carbodent (Stoma). Output and peak temperature findings of self-curing resin polymerization were recorded and values ​​of temperature increase in the tooth chamber were calculated. Two types of materials were used to make external anatomical moulds: 1) silicone impression material Panasil Putty Soft of high and low viscosity and Panasil initial contact Light (Kettenbach) to make two-phase impression; 2) transparent thermoplastic polymer Erkodur (Erkodent), sheet of 1.0 mm thick, vacuum pressed. Results and Discussion. We obtained the following finding of the temperature rise inside the pulp chamber (polymer pattern / silicone matrix): Protemp IV (2,2˚C / 0,2˚C), VisalisTemp (3˚C / 0.3˚C), Protemp II (3,3˚C / 0,5˚C), Structur (3,4˚С/0,6˚С), Karbodent (6.7˚C / 3.0˚C). Conclusions. Exothermic effects during intra oral fabrication of temporary crowns can be minimized by polymerization of resins in the silicone mould as this material can absorb and dissipate heat.