title: Influence of the implant drill design and sequence on temperature changes during site preparation.
abstract: OBJECTIVE
  The purpose of this study was to compare bone temperature changes during implant drilling with two drill designs employed in three different drilling sequences.
  
  
  METHODS
  Two implant drill designs and three drilling sequences were evaluated in vitro using artificial bone cylinders. The evaluated drills were different only in the cutting-surface length (control, 16 mm; test, 4 mm). Three drilling sequences (control A, test B1, and test B2) were evaluated with and without irrigation. Temperatures were measured with thermocouple technology. The temperature changes generated by the final drill of each sequence were recorded as the experimental results and were subjected to the Student t test.
  
  
  RESULTS
  There were statistically significant differences in temperature changes when comparing the control group A with the test groups B1 (P = .001) and B2 (P = .01) during drilling without coolant. The mean temperature changes were 12.4°C, 6.5°C, and 13.7°C for groups A, B1, and B2, respectively. The Student t test showed statistically significant differences between temperature changes of the control group A and the test groups B1 (P < .01) and B2 (P < .05) during drilling with coolant. The mean temperature changes were 0.9°C, 0.7°C, and 1.9°C for groups A, B1, and B2, respectively.
  
  
  CONCLUSIONS
  Reduction in length of the cutting surface of the drill may limit frictional heat. Drills with the same length of cutting surface may induce lower bone temperature changes, when considering a preliminary drilling step with a pilot drill.
authors.forename: Gianpaolo
authors.initials: G
authors.lastname: Sannino
authors.forename: Paolo
authors.initials: P
authors.lastname: Capparé
authors.forename: Enrico F
authors.initials: EF
authors.lastname: Gherlone
authors.forename: Alberto
authors.initials: A
authors.lastname: Barlattani
mesh_terms: D001831:Body Temperature; D001842:Bone and Bones / Q000473:pathology*; D003758:Dental Implantation, Endosseous / Q000379:methods*; D003762:Dental Instruments; D004867:Equipment Design; D006358:Hot Temperature; D006801:Humans; D010020:Osteonecrosis; D010027:Osteotomy; D019736:Prostheses and Implants; D007507:Therapeutic Irrigation / Q000295:instrumentation; D013817:Thermography / Q000379:methods