The aim of this thesis was to investigate in vitro temperature changes during drilling in the bone by using implant drills which are produced by different companies. In this study, bone specimens obtained from fresh beef ribs were used. Drilling has been performed on the bone specimens by using the Ankylos, Astra Tech, Nobel Biocare, Bredent Straumann implant systems with 2 kilograms static downward force and 30±2 0C ambient temperature. Two K type thermocouples were placed in the 5 and 10 mm depth of bone specimens and temperature was measured at the distance of 1 mm from the implant drills. In our study, different experimental models were prepared to make implant site preparation. The experiment was based on four groups: in Group 1, drills were used for the first osteotomy at the speed of 150 rpm without irrigation; in Group 2 drills were used for the first osteotomy at the speed of 1200 rpm with irrigation (40 mL/min); in Group 3 drills were used for up to 30'th osteotomies at the speed of 150 rpm without irrigation and in Group 4 drills were used for up to 30'th osteotomies at the speed of 1200 rpm with irrigation (40 mL/min). Whole osteotomies were performed in eight minutes with 3.5±0.3 mm diameter drills and temperature values obtained in the eight equal time periods were recorded. Statistical analysis of the values was performed by using Repeated Measures and Kruskall Wallis tests. No significant difference was observed in each group for different implant brands according to temperature changes while drilling of the bone specimens (p<0.05). The critical temperature (47C+) was not recorded in any of the experimental models. In the 5 and 10 mm depth, the temperature change levels were similar to each other. Therefore, although the mean temperature values were similar in the irrigation and non-irrigation systems, the values obtained by subtraction of initial temperatures were significantly higher in non-irrigation groups. The results of this study showed that different implant drills (produced by Ankylos, Astra Tech, Nobel Biocare, Bredent, Straumann companies) and repeated drilling do not cause significant temperature rise during the osteotomy in bone specimens. Otherwise, we concluded that both irrigation and non-irrigation systems are safe in reasonable working conditions.