The effect of chlorhexidine gel on removal torque values of different dental implant systems

SUMMARY Ozdemir K. The Effect of Chlorhexidine Gel on Removal Torque Values of Different Dental Implant Systems. Yeditepe University Health Sciences Institute, PhD Thesis in Prosthetic Dentistry, İstanbul, 2012. Osseointegrated implants is a good represent now on acceptable treatment modality for complete or edentulous patients. Despite the recognized success, mechanical and biological failures associated with implant restorations represent a challenge to clinicians. Among the types of mechanical and biological failures abutment screw loosing and periimplantitis is still the most frequently reported complications. The aim of this study was to verify whether screw abutment lubrication with chlorhexidine gel can generate higher preload values compared to non-lubricated screws and determine if chlorhexidine has any extra mechanical advantage with it's biological advantage. Total of 24 new implants and abutments from (Astra, Zimmer, Straumann Bone Level, Straumann Standart Plus) each system were mounted in acrylic resin and the abutments were distrubuted in dry and chlorhexidine groups. In the chlorhexidine group the inner threads were filled with chlorhexidine gel. All abutments were fastaned with digital torque screw driver (DID-4) to their manifacturers recomended torque values and then detorqued after 5 minutes for 15 times. Thermocycling was performed for all implant systems both for dry and chlorhexidine groups for 1000 cycle. The mean detorque values were calculated and compared by student t-test and oneway anova test (p<0.05). Straumann Bone Level presented both in dry and chlorhexidine conditions showed the lowest loss of the initial torque values (2.66Ncm and 3.91Ncm respectively). Astra has the highest initial torque loss both for dry and chlorhexidine conditions (4.01Ncm and 6.23Ncm respectively). In conclusion there was always a loss in initial torque values when the removal torque was measured under both dry and chlorhexidine conditions. The chlorhexidine group presented in all implant abutment systems showed lower detorque values than the dry groups. Termocycling has no effect on removal torque values both in dry and chlorhexidine groups for all implant systems. Keywords: Dental Implants, Chlorhexidine, Removal Torque