Implant stability comparison of immediate and delayed maxillary implant placement by use of resonance frequency analysis--a clinical study.

The purpose of this study was to objectively evaluate the stability of dental implants by use of resonance frequency analysis (RFA). In this study, 60 Nobel Replace Tapered Groovy implants were placed in the premolar region of the maxilla in 60 patients. Thirty implants were placed immediately after tooth extraction and 30 implants were placed in healed bone sites. Implant stability quotient (ISQ) was obtained by use of the Osstell Mentor device and was recorded at the time of implant placement (T1) and 20 weeks after placement, at the time of implant loading (T2). All implants were not functionally loaded during the follow up period. Data were analyzed using simple linear regression. No implant failures were reported in the 6-month follow up period. The mean ISQvalue for immediate implant placement was 61.43 at T1 and 66.23 at T2. The implants placed in healed bone showed higher ISQvalues compared to the immediately placed implants (mean ISQvalue was 64.17 at T1 and 68.83 at T2). Differences in the mean ISQ values were statistically significant (p < 0.001). After the completed period of osseointegration, the mean ISQ value was 4.8 for immediately placed implants compared to 4.67 for implants placed in delayed sites.