Influence of Bone Quality, Drilling Protocol, Implant Diameter/Length on Primary Stability: An In Vitro Comparative Study on Insertion Torque and Resonance Frequency Analysis

2020 ◽  
Vol 46 (3) ◽  
pp. 182-189 ◽  
Author(s):  
Davide Farronato ◽  
Mattia Manfredini ◽  
Michele Stocchero ◽  
Mattia Caccia ◽  
Lorenzo Azzi ◽  
...  

The aim of this study was to evaluate the influence of bone quality, drilling technique, implant diameter, and implant length on insertion torque (IT) and resonance frequency analysis (RFA) of a prototype-tapered implant with knife-edge threads. The investigators hypothesized that IT would be affected by variations in bone quality and drilling protocol, whereas RFA would be less influenced by such variables. The investigators implemented an in vitro experiment in which a prototype implant was inserted with different testing conditions into rigid polyurethane foam blocks. The independent variables were: bone quality, drilling protocol, implant diameter, and implant length. Group A implants were inserted with a conventional drilling protocol, whereas Group B implants were inserted with an undersized drilling protocol. Values of IT and RFA were measured at implant installation. IT and RFA values were significantly correlated (Pearson correlation coefficient: 0.54). A multivariable analysis showed a strong model. Higher IT values were associated with drilling protocol B vs A (mean difference: 71.7 Ncm), implant length (3.6 Ncm increase per mm in length), and substrate density (0.199 Ncm increase per mg/cm3 in density). Higher RFA values were associated with drilling protocol B vs A (mean difference: 3.9), implant length (1.0 increase per mm in length), and substrate density (0.032 increase per mg/cm3 in density). Implant diameter was not associated with RFA or IT. Within the limitations of an in vitro study, the results of this study suggest that the studied implant can achieve good level of primary stability in terms of IT and RFA. A strong correlation was found between values of IT and RFA. Both parameters are influenced by the drilling protocol, implant length, and substrate density. Further studies are required to investigate the clinical response in primary stability and marginal bone response.

2020 ◽  
pp. 026248932097179
Author(s):  
Margherita Tumedei ◽  
Adriano Piattelli ◽  
Antonello Falco ◽  
Francesco De Angelis ◽  
Felice Lorusso ◽  
...  

The dental implant primary stability and micromovement absence represent critical factor for dental implant osseointegration. The aim of the present in vitro investigation was to simulate the bone response on different polyurethane densities the effect of self-tapping threads and round apex implant geometry. A total of 40 implants were positioned in D1, D2, D3 and D4 polyurethane block densities following a calibrated drilling protocol. The Insertion, removal Torque and resonance frequency analysis (RFA) means were calculated. All experimental conditions showed insertion torque values >30 Ncm. A significant higher insertion torque, removal and RFA was present in D1 polyurethane. Similar evidences were evidenced for D3 and D4. The effectiveness of the present study suggested a valuable clinical advantage for self-tapping threads and round apex implant using, such as in case of reduced bone density in the posterior maxilla


2014 ◽  
Vol 40 (4) ◽  
pp. 438-447 ◽  
Author(s):  
Giorgio Deli ◽  
Vincenzo Petrone ◽  
Valeria De Risi ◽  
Drazen Tadic ◽  
Gregory-George Zafiropoulos

Primary stability is an indicator of subsequent osseointegration of dental implants. However, few studies have compared the implant stability among anatomical regions and bone types; thus, not enough data exist regarding the stability of implants placed in regenerated bone (RB). The present study evaluated primary and long-term stability of implants placed in RB and non-regenerated healed bone (HB). A total of 216 screw cylinder implants were placed in 216 patients (98 in HB and 118 in RB, 6 [RB6, N = 68] or 12 [RB12, N = 50] months after tooth extraction). Implant stability was evaluated using resonance frequency analysis (RFA) measured at the time of implant placement (E1), at the time of loading (4 months after placement, E2), and 4 months after loading (E3). Various clinically relevant measurements were obtained, such as implant diameter, length, and location, as well as bone quality. At E1, implant location, bone quality, and experimental group significantly affected implant stability (all at P < .05). At E2, implant location, diameter, length, and experimental group significantly affected implant stability (all at P < .05). At E3, bone quality, implant diameter, length, and experimental group significantly affected implant stability (all at P < .01). Stability for the RB12 group was significantly higher than all other corresponding values; further, the values did not change significantly over time. For the HB and RB6 groups, stability was significantly higher at E2 than at E1 (P < .001) and was no different between E2 and E3. Implant location, length, and experimental group were associated with these differences (all at P < .05). Compared with HB and RB6, higher implant stability may be achieved in regenerated bone 12 months post-extraction (RB12). This stability was achieved at E1 and maintained for at least 8 months. Variables such as implant length, diameter, and bone quality affected the stability differently over time. Implant stability varied in different anatomic regions and with regard to different healing processes in the bone.


2020 ◽  
Vol 9 (9) ◽  
pp. 2977
Author(s):  
Tanja Grobecker-Karl ◽  
Anthony Dickinson ◽  
Siegfried Heckmann ◽  
Matthias Karl ◽  
Constanze Steiner

Insertion energy has been advocated as a novel measure for primary implant stability, but the effect of implant length, diameter, or surgical protocol remains unclear. Twenty implants from one specific bone level implant system were placed in layered polyurethane foam measuring maximum insertion torque, torque–time curves, and primary stability using resonance frequency analysis (RFA). Insertion energy was calculated as area under torque–time curve applying the trapezoidal formula. Statistical analysis was based on analysis of variance, Tukey honest differences tests and Pearson’s product moment correlation tests (α = 0.05). Implant stability (p = 0.01) and insertion energy (p < 0.01) differed significantly among groups, while maximum insertion torque did not (p = 0.17). Short implants showed a significant decrease in implant stability (p = 0.01), while reducing implant diameter did not cause any significant effect. Applying the drilling protocol for dense bone resulted in significantly increased insertion energy (p = 0.02) but a significant decrease in implant stability (p = 0.04). Insertion energy was not found to be a more reliable parameter for evaluating primary implant stability when compared to maximum insertion torque and resonance frequency analysis.


Author(s):  
Burcu Diker ◽  
Nurettin Diker ◽  
Onjen Tak

The purpose of the present study was to investigate the intra-observer and inter-observer reliability of three resonance frequency analysis (RFA) devices and to compare the implant stability quotient (ISQ) values according to implant macro design and diameter in two different bone densities. A total of 64 implants (Neoss Proactive) of varying diameters (3.5 and 4.0 mm) and implant macro design (tapered and straight) were placed in two artificial bone blocks (the density of type 2 and 3). The implant primary stability was measured using Osstell IDx, Osstell Beacon and Penguin RFA. The ISQ value of each implant was measured by two observers and recorded five times in two directions. The intra-observer and inter-observer reliability of RFA devices were evaluated. In addition to that, mean ISQ values were calculated for each RFA device to evaluate the effect of implant diameter, implant macro design, and bone density on ISQ values. ISQ values were significantly higher for implants placed within the type 2 bone than for the type 3 bone. The 4.0 mm diameter implants presented higher ISQ values than 3.5 mm diameter implants. The intra-class correlation coefficient (ICC) values for intra-observer reliability were above 0.85 for each observer and the ICC values for inter-observer reliability were 0.94, 0.93, 0.98 for Osstell IDx, Osstell Beacon and Penguin RFA, respectively. Although there was excellent inter-observer reliability with three RFA devices, the intra-observer reliability of Osstell Beacon and Penguin RFA were slightly better than Osstell IDx. Bone density and implant diameter were parameters affecting the primary stability of implants.


Polymers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1020 ◽  
Author(s):  
Luca Comuzzi ◽  
Giovanna Iezzi ◽  
Adriano Piattelli ◽  
Margherita Tumedei

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.


Author(s):  
Luca Comuzzi ◽  
Margherita Tumedei ◽  
Camillo D’Arcangelo ◽  
Adriano Piattelli ◽  
Giovanna Iezzi

Background: Several different dental implant microgeometries have been investigated in the literature for use in low-density bone sites. The polyurethane solid rigid blocks represent an optimal in vitro study model for dental implants, because their composition is characterized by symmetrical linear chains of monomers of hexa-methylene sequences producing a self-polymerization process. The aim of the present investigation was to evaluate the primary stability of cylindrical and tapered implants positioned into low-density polyurethane solid rigid blocks. Materials and Methods: Two different macrogeometries, cylindrical (4 mm diameter and 10 mm length) and tapered dental implants (4.20 mm diameter and 10 mm length), were investigated in the present study. The implants were inserted into 10 PCF and 20 PCF polyurethane blocks, with and without an additional cortical layer. The insertion torque (IT) values, the removal torque values (RTVs), and the resonance frequency analysis (RFA) values were measured and recorded. Results: A total of 80 sites were tested, and a significant increased primary stability (PS) was detected in favour of tapered dental implants when compared to cylindrical implants in all experimental conditions (p < 0.05). Higher IT, RT, and RFA values were measured in tapered implants in 10 and 20 PCF polyurethane blocks, both with and without the additional cortical layer. Conclusions: Both implants showed sufficient primary stability in poor density substrates, while, on the other hand, the tapered microgeometry showed characteristics that could also lead to clinical application in low-density posterior maxillary sites, even with a drastically decreased bone cortical component.


Sign in / Sign up

Export Citation Format

Share Document