Effect of implant macrogeometry on peri-implant healing outcomes: a randomized clinical trial

Abstract

Show to the clinician that the macrogeometry and drilling protocols did not interfere in the clinical behavior of the implants during the healing process. However, the IT, primary and secondary stability, is quite dependent of the surgeon experience.

Implant primary stability depending on protocol and insertion mode — an ex vivo study

“…The optimization of loading protocols requires establishing a patient-specific protocol [14]. The relationship between shape and shear strength during implant placement modulates the bone compression [11]. Osteotomy techniques with a narrower final drill have been shown to create a better bone-to-implant contact with enhanced primary stability values [18].…”

“…In addition, high stress is known to alter angiogenesis and impair new vessel formations, to induce local hypoxia and necrosis, inhibiting new bone formation and to adversely affect implant stability [4,7,10,28,37]. Also, higher degrees of primary stability do not necessarily translate into high degrees of secondary stability [11]. After a latency of 1 week, necrotic bone fills the space between bone and implant whereupon a bone remodeling takes place within 1 to 3 weeks [11,37].…”

“…For evaluation of in vivo primary stability, insertion torque (IT) and resonance frequency analysis (RFA) are well-established methods [2,9]. IT is a mechanical parameter influenced by surgical procedure [10,11], implant design [8,10,11], and bone quality [2,6,8,[10][11][12]. It has been defined by the Foundation for Oral Rehabilitation as the cutting resistance of the bone during implant insertion, the friction, and has been considered an indirect value of implant primary stability [13].…”

“…RFA assumes that the frequency is directly related to the stiffness of the bone-implant interface and the surrounding bone [5,14,15]. High values show a stable implant and allow verification of osseointegration and secondary stability over time [11,16]. RFA is measured by Ostell®-devices (Osstell ISQ, Osstell, Göteborg, Sweden).…”

“…While RFA is expressed in hertz, implant stability quotient (ISQ) is the scale used to quantify RFA values (range 1-100) [14,17]. Even though RFA has been reported to be a reliable, reproducible, and objective method to measure the stiffness of bone-implant-complex [11,18], it has also been reported that RFA data from immediately placed implants could be misleading in increasing in terms of predicting primary stability [19][20][21]. Therefore, this value needs to be supported by another means of quantifying anchorage, especially for immediate loading protocols [18].…”