Next Article in Journal
Crowding-Activity Coupling Effect on Conformational Change of a Semi-Flexible Polymer
Next Article in Special Issue
POSS Compounds as Modifiers for Rigid Polyurethane Foams (Composites)
Previous Article in Journal
Fabrication of Polymer Micelles with Zwitterionic Shell and Biodegradable Core for Reductively Responsive Release of Doxorubicin
Previous Article in Special Issue
Degradable Poly(ether-ester-urethane)s Based on Well-Defined Aliphatic Diurethane Diisocyanate with Excellent Shape Recovery Properties at Body Temperature for Biomedical Application
Article Menu
Issue 6 (June) cover image

Export Article

Open AccessArticle

An In Vitro Evaluation, on Polyurethane Foam Sheets, of the Insertion Torque (IT) Values, Pull-Out Torque Values, and Resonance Frequency Analysis (RFA) of NanoShort Dental Implants

Private practice, via Raffaello 36/a, 31020 San Vendemiano (TV), Italy
Department of Medical, Oral and Biotechnological Sciences, University “G. D’Annunzio” of Chieti-Pescara, Via dei Vestini 31, 66100 Chieti, Italy
Biomaterials Engineering, Catholic University of San Antonio de Murcia (UCAM), Av. de los Jerónimos, 135, 30107 Guadalupe, Murcia, Spain
Villaserena Foundation for Research, Via Leonardo Petruzzi 42, 65013 Città Sant’Angelo (PE), Italy
Author to whom correspondence should be addressed.
Polymers 2019, 11(6), 1020;
Received: 11 May 2019 / Revised: 5 June 2019 / Accepted: 7 June 2019 / Published: 10 June 2019
(This article belongs to the Special Issue Functional Polyurethanes – In Memory of Prof. József Karger-Kocsis)
PDF [2285 KB, uploaded 10 June 2019]


Objectives: The aim of this study was to investigate, in polyurethane foam sheets, the primary implant stability of a NanoShort implant compared to a self-condenser implant and to a standard, conventional implant. Materials and Methods: Three implant designs were evaluated in the present in vitro investigation: The Test implant (NanoShort), the Control A implant (self-condenser), and the Control B implant (standard design). The study was conducted by comparing the insertion torque values, the pull-out strength values, and the resonance frequency analysis (RFA) values of the Test and Control A and B implants inserted in polyurethane foam models of different thicknesses and densities. The foam densities were 10, 20, and 30 pounds per cubic foot (pcf). Three thicknesses of polyurethane foams (1, 2, 3 mm) were evaluated for a total of 640 experimental sites. Results: The Pearson correlation showed a moderate/strong correlation between all study groups (r > 0.3) for insertion torque and pull-out strength levels. Increased stability of the Test implants was obtained in 3 mm polyurethane sheets. The 2.5 and 3.5 mm Test implants presented good stability in 3 mm polyurethane sheets of 20–30 pcf densities. The Control implants showed better results compared to the Test implants in 1, 2, and 3 mm polyurethane sheets with densities of 10, 20, and 30 pcf. Conclusions: The NanoShort dental implant evaluated in this in vitro study showed a high level of stability in some experimental conditions, and could represent a useful tool, especially in the posterior mandible, as an alternative to vertical augmentation procedures. View Full-Text
Keywords: implant stability; insertion torque; pull-out strength; polyurethane foam implant stability; insertion torque; pull-out strength; polyurethane foam

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Share & Cite This Article

MDPI and ACS Style

Comuzzi, L.; Iezzi, G.; Piattelli, A.; Tumedei, M. An In Vitro Evaluation, on Polyurethane Foam Sheets, of the Insertion Torque (IT) Values, Pull-Out Torque Values, and Resonance Frequency Analysis (RFA) of NanoShort Dental Implants. Polymers 2019, 11, 1020.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Polymers EISSN 2073-4360 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top