Comparative In Vitro Evaluation of the Primary Stability in D3 Synthetic Bone of Two Different Shapes and Pitches of the Implant Threads

Background: Implant primary stability can be affected by several factors related to implant macrogeometry, local anatomy, and surgical techniques. The aim of this research was to study primary stability on polyurethane foam sheets of wide-threaded implant design compared to narrow-threaded implants. Materials and methods: Two different implant designs were positioned on D3 density polyurethane blocks in a standardized environment: the wide-threaded implant and the narrow-threaded implant, for a total of 160 specimens. Moreover, for each group, two different sizes were considered: 3.8mm × 12mm and 4.8mm × 12 mm. The insertion torque (IT) values, the removal strength (RT), and the Periotest analyses were evaluated. Results: A significantly higher IT and RT was reported for wide-threaded implants and two-stage implants (p < 0.01), compared to the narrow-threaded implants. The diameters seemed to provide a significant effect on the primary stability for both implants’ geometry (p < 0.01). A higher mean of the one-stage implant was evident in the Periotest measurements (p < 0.01). Conclusions: Both of the implants showed sufficient stability in polyurethane artificial simulation, while the wide-threaded implant design showed a higher primary stability on alveolar cancellous synthetic bone in vitro. Additionally, the prosthetic joint connection seemed to have a determinant effect on Periotest analysis, and the one-stage implants seemed to provide a high stability of the fixture when positioned in the osteotomy, which could be important for the immediate loading protocol.

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Influence of Implant Design and Under-Preparation of the Implant Site on Implant Primary Stability. An In Vitro Study

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17124436 ◽

2020 ◽

Vol 17 (12) ◽

pp. 4436 ◽

Cited By ~ 2

Author(s):

Mariano Herrero-Climent ◽

Bernardo Ferreira Lemos ◽

Federico Herrero-Climent ◽

Carlos Falcao ◽

Helder Oliveira ◽

...

Keyword(s):

In Vitro Study ◽

Primary Stability ◽

Implant Design ◽

Insertion Torque ◽

Bovine Bone ◽

Preparation Technique ◽

Implant Stability ◽

The One ◽

Two Parameters

The aim of this study was to evaluate the effects of different implant sites an under-preparation sequence associated with two different implant designs on implant primary stability measured by two parameters: insertion torque (IT) and implant stability quotient (ISQ). It used two different implants: one cylindrical as a control and another one with a tapered design. The implants were inserted in type III fresh humid bovine bone and four drilling sequences were used: one control, the one proposed by the implant company (P1), and three different undersized (P2, P3 and P4). P2 was the same as P1 without the cortical drill, P3 was without the last pilot drill and P4 was without both of them. The sample size was n = 40 for each of the eight groups. Final IT was measured with a torquemeter and the ISQ was measured with Penguin resonance frequency analysis. Results showed that both ISQ and IT have a tendency to increase as the preparation technique reduces the implant site diameter when compared with the standard preparation, P1. The preparations without cortical drill, P2 and P4, showed the best results when compared with the ones with a cortical drill. Tapered implants always showed higher or the same ISQ and IT values when compared with the cylindrical implants. Giving the limitations of this study, it can be concluded that reducing implant preparation can increase IT and ISQ values. Removing the cortical drill and the use of a tapered design implant are also effective methods of increasing primary implant stability.

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Can the design of the instruments used for undersized osteotomies influence the initial stability of implants installed in low-density bone? An in vitro pilot study

PLoS ONE ◽

10.1371/journal.pone.0257985 ◽

2021 ◽

Vol 16 (10) ◽

pp. e0257985

Author(s):

Márcio de Carvalho Formiga ◽

Arthur Felipe Gehrke ◽

João Paulo De Bortoli ◽

Sergio Alexandre Gehrke

Keyword(s):

Instrument Design ◽

Implant Design ◽

Insertion Torque ◽

Low Density ◽

Implant Stability ◽

Synthetic Bone ◽

Initial Stability ◽

Osteotomy Technique ◽

Final Instrument

Objectives The aims of this study were to compare the initial implant stability obtained using four different osteotomy techniques in low-density synthetic bone, to evaluate the instrument design in comparison to the implant design, and to determinate a possible correlation between the insertion torque and initial stability quotient (ISQ). Materials and methods Four groups were identified in accordance with the osteotomy technique used (n = 10 implants per group): group G1, osteotomy using the recommended drilling sequence; group G2, osteotomy using an undersized compactor drill; group G3, osteotomy using an undersized drill; and group G4, osteotomy using universal osseodensification drills. Two polyurethane blocks were used: block 1, with a medullary portion of 10 pounds per cubic foot (PCF 10) and with a 1 mm cortical portion of PCF 40, and block 2, with a medullary of PCF 15 and with a 2 mm cortical portion of PCF 40. Tapered implants of 4 mm in diameter and 11 mm in length were used. The insertion torque (IT) and ISQ were measured. The dimensions of the final instrument used in each group and the dimensions of the implant were used to calculate the total area of each part, and these data were compared. Results Differences between the four groups were found for IT and ISQ values depending on the technique used for the osteotomy in the two synthetic bone models (p < 0.0001). All groups showed lower values of initial stability in block 1 than in block 2. Conclusions Undersized osteotomies with instruments designed according to the implant body significantly increased the initial stability values compared to beds prepared with universal drills and using the drilling sequence standardized by the manufacturer.

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

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-19-00145 ◽

2020 ◽

Vol 46 (3) ◽

pp. 182-189 ◽

Cited By ~ 1

Author(s):

Davide Farronato ◽

Mattia Manfredini ◽

Michele Stocchero ◽

Mattia Caccia ◽

Lorenzo Azzi ◽

...

Keyword(s):

Resonance Frequency ◽

Bone Quality ◽

Frequency Analysis ◽

Primary Stability ◽

Mean Difference ◽

Insertion Torque ◽

Resonance Frequency Analysis ◽

Bone Response ◽

Implant Length

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.

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New Implant Design with Midcrestal and Apical Wing Thread for Increased Implant Stability in Single Postextraction Maxillary Implant

Case Reports in Dentistry ◽

10.1155/2019/9529248 ◽

2019 ◽

Vol 2019 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

Antonio Scarano ◽

Bartolomeo Assenza ◽

Francesco Inchingolo ◽

Filiberto Mastrangelo ◽

Felice Lorusso

Keyword(s):

Cortical Bone ◽

Dental Implant ◽

Alveolar Bone ◽

Primary Stability ◽

Implant Design ◽

Insertion Torque ◽

Fixture Design ◽

Implant Stability ◽

Implant Placement ◽

Immediate Placement

Background. The immediate placement of a dental implant could represent an option treatment for the rehabilitation of a postextractive missing tooth socket to replace compromised or untreatable teeth, with the advantage of single-session surgery. In this way, the anatomy of the alveolar bone defect, the preservation of the buccal cortical bone, and the primary stability of the fixture represent the critical factors that consent a precise implant placement. Objective. This case report describes a novel fixture design for postextractive alveolar socket immediate implant. Methods. Two patients (25 and 31 years old) were treated for postextractive dental implant placement to replace both central upper incisor teeth with four implants. The residual bone implant gap was not filled with graft or bone substitute. The restoration was provided following a standard loading protocol by a cement-sealed prosthetic abutment. Results. Clinically, all implants positioned showed an excellent insertion torque. No postoperative complications were reported. At 6 months of healing, the buccal cortical bone and the implant stability were present and well maintained. Conclusion. The evidence of this study allows us to underline the possible advantages of this new fixture design for postextractive implant technique.

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Relevant Design Aspects to Improve the Stability of Titanium Dental Implants

Materials ◽

10.3390/ma13081910 ◽

2020 ◽

Vol 13 (8) ◽

pp. 1910 ◽

Cited By ~ 4

Author(s):

M. Herrero-Climent ◽

P. López-Jarana ◽

B. F. Lemos ◽

F. J. Gil ◽

C. Falcão ◽

...

Keyword(s):

Primary Stability ◽

Insertion Torque ◽

Bovine Bone ◽

Resonance Frequency Analysis ◽

Everyday Clinical Practice ◽

Implant Stability Quotient ◽

The Stability ◽

The One ◽

Implant System ◽

Titanium Dental Implants

Post-extractional implants and immediate loading protocols are becoming much more frequent in everyday clinical practice. Given the existing literature about tapered implants, the objective of this paper was to understand whether implant shape had a direct influence on the results of the insertion torque (IT) and implant stability quotient (ISQ). Seven tapered implant prototypes were developed and distributed into three groups and compared with a control cylindrical implant—VEGA by Klockner Implant System. The implants were inserted into bovine bone type III according to Lekholm and Zarb Classification. The sample size was n = 30 for the three groups. Final IT was measured with a torquemeter, and the ISQ was measured with Penguin Resonance Frequency Analysis (RFA). Modifications done to the Prototype I did not reveal higher values of the ISQ and IT when compared to VEGA. In the second group, when comparing the five prototypes (II–VI) with VEGA, it was seen that the values of the ISQ and IT were not always higher, but there were two values of the ISQ that were statistically significantly higher with the 4.0 mm diameter Prototypes II (76.3 ± 6.1) and IV (78 ± 3.7). Prototype VII was the one with higher and significant values of the ISQ and IT. In both diameters and in both variables, all differences were statistically significant enough to achieve the higher values of primary stability values (IT and ISQ). Given the limitations of this study, it can be concluded that when there is an increase of the diameter of the implant and body taper, there is an increase of the ISQ and IT, showing that the diameter of the implant is an important criteria to obtain higher values of primary stability.

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Plasma Transfusions in Hemophilia

Blood ◽

10.1182/blood.v7.7.710.710 ◽

1952 ◽

Vol 7 (7) ◽

pp. 710-720 ◽

Cited By ~ 4

Author(s):

S. VAN CREVELD ◽

M. M. P. PAULSSEN

Keyword(s):

Two Stage ◽

Coagulation Time ◽

Prothrombin Activity ◽

Lasting Effect ◽

One Stage ◽

The One ◽

Rapid Appearance

Abstract Transfusions of heparinized plasma have a greater and more lasting effect on the coagulation time of hemophiliacs than transfusions of citrated plasma. Both in vitro and in vivo, heparinized plasma causes in hemophiliacs a far greater consumption of prothrombin as determined with the two-stage method than citrated plasma. In using the one-stage method no important differences in prothrombin activity are found after transfusions of heparinized and of citrated plasma respectively. This fact was thought to be connected with the more or less rapid appearance of an accelerator. Its a hemophiliac with a circulating anticoagulant, transfusions of heparinized plasma were unable to shorten the coagulation time to any important degree, nor did these transfusions cause an important decrease of serum prothrombin as determined by the two-stage method.

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Mechanical stability and clinical applicability assessment of novel orthodontic mini-implant design

The Angle Orthodontist ◽

10.2319/111412-876.1 ◽

2013 ◽

Vol 83 (5) ◽

pp. 832-841 ◽

Cited By ~ 6

Author(s):

Ha Na Song ◽

Christine Hong ◽

Robert Banh ◽

Tania Ohebsion ◽

Greg Asatrian ◽

...

Keyword(s):

Cortical Bone ◽

Mechanical Stability ◽

Primary Stability ◽

Tension Force ◽

Implant Design ◽

Insertion Torque ◽

Compression Force ◽

Clinical Applicability ◽

The Mean ◽

The Stability

ABSTRACT Objective: To compare the stability and clinical applicability of a novel orthodontic mini-implant design (N2) with the most widely used commercially available (CA) design. Materials and Methods: Two groups of mini-implants were tested: a CA design (1.5-mm diameter, 6-mm length) and N2 (3-mm diameter, 2-mm length, tapered shape). Implants were inserted in bone blocks of cortical bone simulation with varying densities (20 pounds per cubic foot [pcf], 30 pcf, and 40 pcf). A torque test was used to measure maximum insertion torque (MIT) and maximum removal torque (MRT). Compression and tension force vectors were applied at angles of 10°, 20°, 30°, and 40° using customized load pins to determine primary stability. Results: Mean MIT and MRT were higher in the N2 than the CA design at all three cortical bone densities except MRT in 20 pcf bone (not statistically significant). The mean compression force required to displace the N2 at all distances and angulations was greater for the N2 than the CA design. At all displacement distances, the highest mean tension force required for N2 displacement was at 10° angulation, whereas at 30° and 40°, the mean tension force required to displace the CA design was greater. Conclusions: The primary stability of the N2 is superior to that of the CA design and is promising for both orthodontic and orthopedic clinical applicability, especially under compression force. The short length of the N2 reduces risk of damage to anatomic structures and root proximity during placement and orthodontic treatment. The stability of the N2 may be compromised in areas of high bone density and highly angulated tension force.

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Validation of a Procedure for Potency Assessing of a High Purity Factor VIII Concentrate -Comparison of Different Factor VIII Coagulant Assays and Effect of Prediluent

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647295 ◽

1990 ◽

Vol 64 (02) ◽

pp. 251-255 ◽

Cited By ~ 8

Author(s):

Claudine Mazurier ◽

Armelle Parquet-Gernez ◽

Maurice Goudemand

Keyword(s):

Factor Viii ◽

Specific Activity ◽

Assay Method ◽

One Stage ◽

Chromogenic Assay ◽

Coagulant Activity ◽

The One ◽

In Vitro Data

SummaryThe assessment of factor VIII coagulant activity (FVTII: C) in recently available highly purified and concentrated FVTII therapeutic products calls for careful evaluation of assay methodologies. We assayed more than 130 batches of a concentrate with a specific activity of about 150 FVTII :C units/mg protein, using one-stage and two-stage clotting and chromogenic methods. There was good agreement between the potency estimates obtained with the different methods. We also compared the FVTII :C potencies obtained after predilution in buffer or FVIII-deficient plasma using either calibrated plasma or FVTII concentrate as references. With the one-stage assay we found a marked discrepancy between the potency values obtained with buffer and with FVTII-deficient plasma used as prediluents. In order to validate our “in vitro” data we performed 6 “in vivo” analyses in severe haemophilia A patients. On the basis of the overall data obtained we chose to label FVIII potency by using FVIII-deficient plasma as prediluent, reference plasma as standard and the chromogenic assay method.

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In Vivo Recovery of Factor VIII: A Comparison of One-Stage and Two-Stage Assay Methods

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657018 ◽

1979 ◽

Vol 42 (04) ◽

pp. 1230-1239 ◽

Cited By ~ 46

Author(s):

I M Nilsson ◽

T B L Kirkwood ◽

T W Barrowcliffe

Keyword(s):

Factor Viii ◽

Half Life ◽

In Vitro Assays ◽

Two Stage ◽

One Stage ◽

Significant Difference ◽

Assay Methods ◽

The One ◽

Fraction I

SummaryThe recovery and half-life of VIII: C in the plasma of severely haemophilic patients was measured by one-stage and two-stage assays after injection of two Factor VIII concentrates (Hemofil, Hyland and Fraction I-O, Kabi). Plasma volumes were measured with an Evans� Blue technique, and both concentrates and post-infusion samples were measured against the same plasma standard.There was a highly significant difference in recoveries estimated by the two assay methods. The one-stage assays gave the most consistent results, in that the average recovery was 100%, whereas the two-stage assays gave only about 80% of the value expected from in vitro assays. There was no difference in recoveries between the two concentrates.The two-stage assays gave a slightly shorter half-life than the one-stage assays, and the half-life of Hemofil was also shorter than that of Fraction I-O.

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Calculating ISQ Primary Stability of a Dental Implant through Micromotion

Periodica Polytechnica Mechanical Engineering ◽

10.3311/ppme.14192 ◽

2019 ◽

Vol 64 (1) ◽

pp. 43-50

Author(s):

David Pammer

Keyword(s):

Dental Implant ◽

Characteristic Equation ◽

Bone Structure ◽

Primary Stability ◽

Insertion Torque ◽

Element Analysis ◽

Simple Method ◽

Micro Mobility

There are several types of primary and secondary stability measuring methods, but there are no calculating methods to determine direct primary stability. The aim of this work is to make a calculation method for primary stability. The out coming result of the calculation should be the same form and unit as available in the clinical and used RFA (Resonance Frequency Analysis) method, especially the ISQ (Implant Stability Quotient). Dental implant analog screws were inserted in bone modelling standard PUR (Polyurethane) solid foam blocks, and the insertion torque and the micromotion was monitored. The ISQ values of the inserted screws were measured also. On the basis of results, the characteristic equation was determined, which showed an excellent correlation (r = 0.96) between the micro mobility and ISQ. To simulate the micro mobility of an inserted screw with FEA (Finite Element Analysis) in any case of the change the bone material properties is not difficult instead of in vitro and in vivo examinations. Using the simulation results and the characteristic equation the clinically used ISQ value could be determinable. Thanks to this simple method, it is easy to monitor virtually the stability change in any lesion of bone structure. As a result of the conducted measurements and simulations, it can be concluded that the ISQ value, which represent the implant primary stability, can be calculated via FEA. With this simulation method, it is possible to predict and monitor pre-clinically the primary stability of dental implants with new geometries.

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