Assessment of pain associated with insertion torque and primary implant stability

Primary implant stability plays a key role in providing osseointegration. Higher insertion torque indicates higher primary stability. Higher insertion torque is expected to causes higher compressive forces around peri-implant hard tissues. However, the effect of increased insertion torque on patient pain levels has not clearly demonstrated. Several primary stability measuring methods have defined so far and but studies evaluating the correlation between these methods are lacking. Insertion torque, periotest measurements and resonance frequency analysis are mostly preferred because of easy utilization and non-invasiveness. Still, superiority and consistency of the primary stability measuring methods were not clarified. The aim of the present study is to evaluate the relationship between insertion torque and patients pain levels assessed with Visual Analogue Scale (VAS), and to evaluate the relation between insertion torque, periotest measurements and resonance frequency analysis. Fifteen patients having bilateral single tooth absence in the posterior mandible were included in the study. The anxiety levels were recorded using Modified Dental Anxiety Scale (MDAS) before the operation. One implant was randomly placed with high insertion torque and the other with low insertion torque in each patient. A total of 30 implants were placed and insertion torque values were recorded. The resonance frequency analysis and periotest measurements were also noted before finalizing the operation. All patients filled the VAS in line with the pain levels. No correlation was found between pre-operative anxiety levels and patients pain levels. There was no significant difference in pain levels between low and high insertion torques. There were significant correlations between insertion torque, resonance frequency analysis and periotest values.