Determining primary stability for adhesively stabilized dental implants

Abstract

Objectives To examine factors influencing the primary stability of dental implants when stabilized in over-sized osteotomies using a calcium phosphate-based adhesive cement was the objective. Methods Using implant removal torque measurements as a surrogate for primary stability, we examined the influence of implant design features (diameter, surface area, and thread design), along with cement gap size and curing time, on the resulting primary implant stability. Results Removal torque values scaled with implant surface area and increasing implant diameters. Cement gap size did not alter the median removal torque values; however, larger gaps were associated with an increased spread of the measured values. Among the removal torque values measured, all were found to be above 32 Ncm which is an insertion torque threshold value commonly recommended for immediate loading protocols. Conclusion The adhesive cement show potential for offering primary implant stability for different dental implant designs. In this study, the primary parameters influencing the measured removal torque values were the implant surface area and diameter. As the liquid cement prevents the use of insertion torque, considering the relationship between insertion and removal torque, removal torque can be considered a reliable surrogate for primary implant stability for bench and pre-clinical settings. Clinical relevance At present, the primary stability of dental implants is linked to the quality of the host bone, the drill protocol, and the specific implant design. The adhesive cement might find applications in future clinical settings for enhancing primary stability of implants under circumstances where this cannot be achieved conventionally.

Static in bone implants: standard steady-state torque and primary stability in a bioactive kinetic screw

“…The measured value obtained in vitro, and ex vivo experiments determined the torque values for five different synthetic bone densities (polyurethane foam) PCF 10, 15, 20, 30, and 40. The biomechanical results can be mathematically hypothesized for human application by the similar and proportional relationship observed in this and other experimental tests [23] even with different bone densities, using the same protocol [24].…”