Purpose: There is no quantitative gold standard instrumentation to assess the quality of implant osseointegration. The purpose of this exploratory study was to evaluate the response of two devices (one based on resonance frequency analysis, the Osstell device, and another that analyzes the percussion energy response, the Periometer) to assess the primary stability of implants embedded in artificial bone models. Materials and Methods: Standard implants were placed into polyurethane blocks of varying densities, and the two mechanical devices were challenged to test the specimen block series. Both analysis of variance and regression analysis were used to examine the output from each device over each series of specimen blocks as well as to directly compare outputs between the two devices. Results: The stability of the implants increased with the foam density for solid block specimens. Linear regression analysis showed significant correlation between the two instruments for testing with monolithic blocks ( r2 = 0.984). Both devices also indicated that a hybrid block with the greatest density at the top provided the best implant stability versus a hybrid block with relatively low density at the top of the block. However, resonance frequency analysis readings seemed to be more dependent on the density of the top layer of the hybrid blocks. Conclusion: Osstell and Periometer readings were in good agreement for monolithic blocks, and they were reasonably consistent when blocks of hybrid density were tested. Keywords: bone density, dental implant, implant stability, osseointegration