A Retrospective Study on Insertion Torque and Implant Stability Quotient (ISQ) as Stability Parameters for Immediate Loading of Implants in Fresh Extraction Sockets

Table 1

Current available methods for implant stability assessment at pre-, intra-, and postsurgical time points; for each method, advantages and disadvantages have been reported.

	Method	Evaluation	Presurgery	Intrasurgery	Postsurgery	Advantages	Disadvantages	Objectivity
Noninvasive methods
Percussion test	Percussion with tool handle	Qualitative: resonance of the implant in the bone,; clear sound, gloomy sound	Not possible	Certain reliability	Certain reliability	Simple and not expensive	Subjective, poor sensitivity	Doubtful reliability
Radiographic analysis	Endoral RX	Quantitative and qualitative: radiating transparency along the bone implant surface and marginal bone level	Certain reliability	Certain reliability	Certain reliability	Simple and not expensive	Two-dimensional examination, not standardizable, not for short follow-ups (<6 weeks)	Not evaluable
Periotest	Electronic pulse sequence	Quantitative. damping of the periodontium and tooth mobility	Certain reliability	Certain reliability	Certain reliability		Subjective, poor sensitivity, values are not significant	Certain reliability, but more information is needed
Measurement of shear strength (Osseo-Care)	Surgical, for example, by means of a tap	Quantitative: cut resistance of the implant site and bone density	Certain reliability	Highest reliability	Certain reliability		Limited to surgery	Certain reliability
Reverse torque test	Reverse torque test of 20 N/cm of the exposed implant	Quantitative: unscrewing the implant	Not possible	Not possible	Certain reliability		Bone deformation, provocation of failures, false positives on implants longer than 13 mm	Certain reliability
RFA	Magnetic pulses picked up by SmartPeg	Quantitative and qualitative: evaluation of the degree of bone-implant contact on a scale from 1 to 100	Not possible	Highest reliability	Highest reliability	Evaluation of immediate loading and evaluation of the increase in the bone-implant contact for the purpose of final prosthetics		Certain reliability, but more information is needed
Invasive methods
Histologic analysis	Sampling using a milling technique	Bone quantity and bone quality (histomorphometry)	Doubtful reliability	Doubtful reliability	Doubtful reliability	High quality	Invasive	Highest reliability
Removal torque measurement	Disarming test, manual/electronic force application on the implant	Quantitative: force necessary to separate bone-implant unit	Not possible	Doubtful reliability	Certain reliability		Invasive, depends on the implant geometry	Certain reliability