Primary Stability of Dental Implants in Low-Density (10 and 20 pcf) Polyurethane Foam Blocks: Conical vs Cylindrical Implants

Abstract

Background: The aim of the present study was to compare, in low-density polyurethane blocks, the primary implant stability values (micromobility) and removal torque values of three different implant geometries in two different bone densities representing the structure of the human posterior jaws. Methods: A total of 60 implants were used in the present investigation: twenty implants for each of three groups (group A, group B, and group C), in both polyurethane 10 pcf and 20 pcf densities. The insertion torque, pull-out torque, and implant stability quotient (ISQ) values were obtained. Results: No differences were found in the values of Group A and Group B implants. In both these groups, the insertion torques were quite low in the 10 pcf blocks. Better results were found in the 20 pcf blocks, which showed very good stability of the implants. The pull-out values were slightly lower than the insertion torque values. High ISQ values were found in Group A and B implants. Lower values were present in Group C implants. Conclusions: The present investigation evaluated implants with different geometries that are available on the market, and not experimental implants specifically created for the study. The authors aimed to simulate real clinical conditions (poor-density bone or immediate post-extraction implants) in which knowledge of dental implant features, which may be useful in increasing the primary stability, may help the oral surgeon during the surgery planning.

An in vitro evaluation on polyurethane foam sheets of the insertion torque, removal torque values, and resonance frequency analysis (RFA) of a self-tapping threads and round apex implant

“…The primary implant stability represents the clinical main condition that could determine the long-term success of implants osseointegration and is deeply influenced by the implant surface geometry. 12,32,33…”

Osseodensification Drilling vs. Standard Protocol of Implant Site Preparation: An In Vitro Study on Polyurethane Foam Sheets

“…The Test A implant presented a narrow-thread shape, double thread pitch, and self-tapping apex [44]. The Test B macro design presented wider thread, no double thread pitch, a round, not self-tapping, apex with healing chambers between the cutting surface of the threads [44].…”

“…According to the previous study by Comuzzi et al [19,44], two different types of solid rigid polyurethane 120 mm × 170 mm × 31 mm foam blocks (SawBones H, Pacific Research Laboratories Inc., Vashon, WA, USA) were used for this study: the first one characterized by 10 pounds per cubic foot (pcf) with a 1 mm cortical of 30 pcf, and the second characterized by 10 pounds per cubic foot (pcf) without cortical.…”

“…The Sample-size calculation was based on mean and standard deviation of a previous study [44], with an alpha error of 0.05, an effect size of 0.75, and power (1-beta) of 0.95. The minimum number was 42 sites for each drilling protocol, for a total of 84 sites.…”

The Effectiveness of Osseodensification Drilling Protocol for Implant Site Osteotomy: A Systematic Review of the Literature and Meta-Analysis

“…In this paper, we analyzed the osseodensification technique operating in the opposite rotatory direction than the conventional drills due to the use of different drills with an exclusive and patented design. Because of this technique, it is possible the bone condensing toward the osteotomy walls within the same surgery moment of the implant site preparation [ 9 , 10 , 11 , 12 , 13 , 14 , 15 ].…”