Temperature Changes in Cortical Bone after Implant Site Preparation Using a Single Bur versus Multiple Drilling Steps: An In Vitro Investigation.
OBJECTIVE
The study aims to test the hypothesis of no differences in temperature variation by using a single bur for implant site preparation as compared with conventional drilling sequence using multiple burs with incremental diameter.


METHODS
Synthetic blocks of bone (type I density) were used for drilling procedures.
Group 1 and Group 2 - drilling with three consecutive burs for a 4.1 mm cylindrical implant and for a 4.3 mm conical implant, respectively; Group 3 - drilling with a single bur for a 4.2 mm conical implant. For each group, 20 drilling procedures were performed without irrigation and 20 with external irrigation. The temperature in the cortical bone during osteotomy for implant site preparation was measured through a thermocouple.


RESULTS
The mean temperatures and standard deviations for the drilling without irrigation were: 25.5 ± 1.24°C for Group 1; 28.1 ± 1.76°C for Group 2; 26.5 ± 1.79°C for Group 3. Considering the drilling with irrigation, the mean values and standard deviations were: 20.4 ± 1.17°C for Group 1; 22.2 ± 1.38°C for Group 2; 20.2 ± 0.83°C for Group 3. Groups 1 and 3 yielded similar results, while Group 2 displayed significantly higher temperature increase than the other two groups.


CONCLUSIONS
The single bur drilling protocol did not produce greater bone heating than the conventional protocol and may be considered a safe procedure.
Biotecnos Research Center, Santa Maria, Brazil.|Catholic University of Uruguay, Montevideo, Uruguay.
Sergio Alexandre
SA
Gehrke
New York University, New York, NY, USA.|private practice, Gretz-Armainvilliers, France.
Raphaél
R
Bettach
Department of Biomedical, Surgical and Dental Sciences, Università degli Studi di Milano, Milan, Italy.|Section of Endodontics and Implant Surgery, Dental Clinic, IRCCS Istituto Ortopedico Galeazzi, Milan, Italy.
Silvio
S
Taschieri
private practice, Paris, France.
Gilles
G
Boukhris
Università degli Studi di Milano, Department of Biomedical, Surgical and Dental Sciences, Dental Clinic, IRCCS Istituto Ortopedico Galeazzi, Milan, Italy.
Stefano
S
Corbella
Research Center in Oral Health, Department of Biomedical, Surgical and Dental Sciences, IRCCS Istituto Ortopedico Galeazzi, Università degli Studi di Milano, Milan, Italy.
Massimo
M
Del Fabbro
D016723:Bone Remodeling; D000071538:Cortical Bone; D003758:Dental Implantation, Endosseous / Q000379:methods*; D004867:Equipment Design; D006801:Humans; D013696:Temperature
bone surgery; cortical bone; dental implants; irrigation methods; osteotomy; thermocouple