Implant Abutment Screw Reverse Torque Values Before and After Plasma Cleaning

2013 ◽  
Vol 26 (4) ◽  
pp. 331-333 ◽  
Author(s):  
Costanza Micarelli ◽  
Luigi Canullo ◽  
Paolo Baldissara ◽  
Marco Clementini
Keyword(s):  
Plasma Cleaning ◽  
Reverse Torque ◽  
Implant Abutment ◽  
Before And After ◽  
Torque Values ◽  
Abutment Screw

scholarly journals A Novel Technique Using Polytetrafluoroethylene Tape to Solve Screw Loosening Complication in Implant-Supported Single Crowns

2020 ◽  
Vol 18 (1) ◽  
pp. 125
Author(s):  
Luis F. Félix ◽  
Michell Medina ◽  
Cristina Gómez-Polo ◽  
Rubén Agustín-Panadero ◽  
Rocío Ortega ◽  
...  
Keyword(s):  
Control Group ◽  
Screw Loosening ◽  
Novel Technique ◽  
Reverse Torque ◽  
Titanium Screws ◽  
Implant Abutment ◽  
Torque Values ◽  
Single Crowns ◽  
Screw Group ◽  
Abutment Screw

This study aimed to analyze a novel technique to make screws with greater untightening resistance and to solve screw loosening in implant-supported single crowns. Thirty grade IV titanium straight abutments were screwed onto 30 external hex implants using grade IV titanium screws (30 Ncm). They were exposed to cyclic loading (300,000 cycles, 200 N). Samples were divided into 4 groups (15 samples per group): new screws (SCREW group) (control), reused screws (rSCREW group), new screws wrapped with polytetrafluoroethylene (PTFE) tape (PTFE group), and reused screws wrapped with PTFE tape (rPTFE group). Reverse torque values (RTVs) were recorded with a digitally calibrated implant motor. Mean RTVs observed were 14.46 N (±1.10 N) for the control group, 14.42 N (±1.22 N) for the rSCREW group, 19.97 N (±1.16 N) for the PTFE group, and 19.13 N (±2.38 N) for the rPTFE group. Statistically significant differences were found between RTVs of both groups employing screws without PTFE tape (SCREW and rSCREW groups) compared with those using screws wrapped with PTFE tape (PTFE and rPTFE) (p < 0.001). These results suggest that wrapping the implant–abutment screw with PTFE tape may effectively lower the risk of loosening and even constitute a solution when this complication occurs in implant single crowns.

Effect of Screw Channel Angulation on Reverse Torque Values of Dental Implant Abutment Screws

2019 ◽  
Vol 28 (9) ◽  
pp. 969-972
Author(s):  
Eric Hu ◽  
Anton Petrich ◽  
Glen Imamura ◽  
Christopher Hamlin
Keyword(s):  
Dental Implant ◽  
Screw Channel ◽  
Reverse Torque ◽  
Implant Abutment ◽  
Torque Values ◽  
Dental Implant Abutment

scholarly journals Axial Displacements and Removal Torque Changes of Five Different Implant-Abutment Connections under Static Vertical Loading

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 699 ◽  
Author(s):  
Ki-Seong Kim ◽  
Young-Jun Lim
Keyword(s):  
Static Loading ◽  
Testing Machine ◽  
Butt Joint ◽  
Removal Torque ◽  
Vertical Loading ◽  
Implant Abutment ◽  
Before And After ◽  
Masticatory Force ◽  
Torque Values ◽  
Molar Region

The aim of this study was to examine the settling of abutments into implants and the removal torque value under static loading. Five different implant-abutment connections were selected (Ext: external butt joint + two-piece abutment; Int-H2: internal hexagon + two-piece abutment; Int-H1: internal hexagon + one-piece abutment; Int-O2: internal octagon + two-piece abutment; Int-O1: internal octagon + one-piece abutment). Ten implant-abutment assemblies were loaded vertically downward with a 700 N load cell at a displacement rate of 1 mm/min in a universal testing machine. The settling of the abutment was obtained from the change in the total length of the entire implant-abutment unit before and after loading using an electronic digital micrometer. The post-loading removal torque value was compared to the initial torque value with a digital torque gauge. The settling values and removal torque values after 700 N static loading were in the following order, respectively: Ext < Int-H1, Int-H2 < Int-O2 < Int-O1 and Int-O2 < Int-H2 < Ext < Int-H1, Int-O1 (α = 0.05). After 700 N vertical static loading, the removal torque values were statistically different from the initial values, and the post-loading values increased in the Int-O1 group and Int-H1 group (α = 0.05) and decreased in the Ext group, Int-H2 group, and Int-O2 group (α = 0.05). On the basis of the results of this study, it should be taken into consideration that a loss of the preload due to the settling effect can lead to screw loosening during a clinical procedure in the molar region where masticatory force is relatively greater.

scholarly journals In Vitro Evaluation of Manual Torque Values Applied to Implant-Abutment Complex by Different Clinicians and Abutment Screw Loosening

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Onur Dincer Kose ◽  
Burcin Karataslı ◽  
Sabit Demircan ◽  
Taha Emre Kose ◽  
Erhan Cene ◽  
...  
Keyword(s):  
Dynamic Loading ◽  
Optical Microscope ◽  
Control Group ◽  
Screw Loosening ◽  
Loading Test ◽  
Torque Wrench ◽  
Implant Abutment ◽  
Torque Values ◽  
Abutment Screw

Preload is applied to screws manually or using a torque wrench in dental implant systems, and the preload applied must be appropriate for the purpose. The aim of this study was to assess screw loosening and bending/torsional moments applied by clinicians of various specialties following application of manual tightening torque to combinations of implants and abutments. Ten-millimeter implants of 3.7 and 4.1 mm diameters and standard or solid abutments were used. Each group contained five implant-abutment combinations. The control and experimental groups comprised 20 and 160 specimens, respectively. Implants in the experimental group were tightened by dentists of different specialties. Torsional and bending moments during tightening were measured using a strain gauge. Control group and implants with preload values close to the ideal preload were subjected to a dynamic loading test at 150 N, 15 Hz, and 85,000 cycles. The implants that deformed in this test were examined using an optical microscope to assess deformities. Manual tightening did not yield the manufacturer-recommended preload values. Dynamic loading testing suggested early screw loosening/fracture in samples with insufficient preload.

scholarly journals An Indirect Method to Measure Abutment Screw Preload: A Pilot Study Based on Micro-CT Scanning

2015 ◽  
Vol 26 (6) ◽  
pp. 596-601 ◽  
Author(s):  
Carlos Eduardo E. Rezende ◽  
Jason Alan Griggs ◽  
Yuanyuan Duan ◽  
Amanda M. Mushashe ◽  
Gisele Maria Correr Nolasco ◽  
...  
Keyword(s):  
Ct Scanning ◽  
Measuring Method ◽  
Micro Ct ◽  
Ct Scanner ◽  
Removal Torque ◽  
Ct Technique ◽  
Original Length ◽  
Implant Abutment ◽  
Torque Values ◽  
Abutment Screw

This study aimed to measure the preload in different implant platform geometries based on micro-CT images. External hexagon (EH) implants and Morse Tapered (MT) implants (n=5) were used for the preload measurement. The abutment screws were scanned in micro-CT to obtain their virtual models, which were used to record their initial length. The abutments were screwed on the implant with a 20 Ncm torque and the set composed by implant, abutment screw and abutment were taken to the micro-CT scanner to obtain virtual slices of the specimens. These slices allowed the measurement of screw lengths after torque application and based on the screw elongation. Preload values were calculated using the Hooke's Law. The preloads of both groups were compared by independent t-test. Removal torque of each specimen was recorded. To evaluate the accuracy of the micro-CT technique, three rods with known lengths were scanned and the length of their virtual model was measured and compared with the original length. One rod was scanned four times to evaluate the measuring method variation. There was no difference between groups for preload (EH = 461.6 N and MT = 477.4 N), but the EH group showed higher removal torque values (13.8±4.7 against 8.2±3.6 Ncm for MT group). The micro-CT technique showed a variability of 0.053% and repeatability showed an error of 0.23 to 0.28%. Within the limitations of this study, there was no difference between external hexagon and Morse taper for preload. The method using micro-CT may be considered for preload calculation.

The Effect of a Positioning Index on the Biomechanical Stability of Tapered Implant-Abutment Connections

2015 ◽  
Vol 41 (2) ◽  
pp. 139-143 ◽  
Author(s):  
Eduardo Aydos Villarinho ◽  
André Cervieri ◽  
Rosemary Sadami Arai Shinkai ◽  
Márcio Lima Grossi ◽  
Eduardo Rolim Teixeira
Keyword(s):  
Strain Gauges ◽  
Biomechanical Stability ◽  
Tightening Torque ◽  
Mechanical Cycling ◽  
Single Crown ◽  
Implant Abutment ◽  
Kolmogorov Smirnov ◽  
Torque Values ◽  
Tapered Connection ◽  
Abutment Screw

The biomechanical stability of the implant-abutment connection is critical for the success of implant-supported restorations. This study investigated the effect of a positioning index on the abutment screw preload values of tapered connection implants. Twenty Morse taper implants presenting an internal locking hex received 10 solid and 10 straight screw retained abutments for cemented single-crown restorations. Ten abutments had a positioning index to fit the internal locking hex of the implant (straight), and 10 were locked only by the implant taper (solid). The preload values for each abutment screw after a tightening torque were registered by strain gauges. Prosthetic crowns were placed on each abutment and subjected to mechanical cycling. Detorque forces were applied to each abutment and compared with the initial torque values. Data were statistically analyzed using Kolmogorov-Smirnov and Student t tests. The nonindexed group presented higher initial preload (6.05 N ± 0.95 N) compared with the indexed group (4.88 N ± 0.92 N; P &lt; .05). After cycling, the nonindexed group exhibited less reduction of preload (13.84% ± 6.43%) compared with the indexed group (52.65% ± 14.81%; P &lt; .01). Indexed tapered abutments for single-crown restorations might represent greater biomechanical risk under function.

scholarly journals Reverse torque values in indexed abutments

2013 ◽  
Vol 1 (3) ◽  
pp. 192
Author(s):  
Daiane Cerutti-Kopplin ◽  
Dimas João Rodrigues Neto ◽  
Accácio Lins Do Valle ◽  
Jefferson Ricardo Pereira ◽  
Luis Gustavo Nunes Dias Pinho
Keyword(s):  
Mechanical Stability ◽  
Insertion Torque ◽  
Average Percentage ◽  
Reverse Torque ◽  
Torque Wrench ◽  
Significant Difference ◽  
Implant Abutment ◽  
Analysis Of Results ◽  
Torque Values ◽  
Biomechanical Instability

Mechanical stability of implant-abutment set is fundamentally important for the success in implant supported rehabilitation. For this, the knowledge about torque removal values is essential. In this way, the objective of this work was to evaluate the torque reverse values in indexed abutments of Morse Taper system. Five Morse taper implants with their respective abutments were tested (n=5). Each abutment received a sequence of two consecutive torques in insertion (15Ncm) with an interval of ten minutes, and one reverse torque, all measured by digital torque wrench. The t-student test with 5% significance was used to evaluate the data. The analysis of results showed there is statistical significant difference in reverse torque values between the insertion torque value and reverse torque value intra-group, the indexed abutments presented an average percentage of torque loosing of 15% (P=0.002). It is possible to conclude that the use of indexed abutments of Morse taper system presented statistical significant reduction of reverse torque values, which in turns increase the risk of no biomechanical instability.

scholarly journals Effect of Wet Field on the DE Torque Values of Abutment Screws

2020 ◽  
Vol 11 (SPL3) ◽  
pp. 843-846
Author(s):  
Pravinya Sam ◽  
Suresh Venugopalan ◽  
Dhanraj Ganapathy
Keyword(s):  
Artificial Saliva ◽  
Blood Clot ◽  
Screw Loosening ◽  
Screw Hole ◽  
Significant Difference ◽  
Implant Abutment ◽  
Torque Values ◽  
Soft Tissue Inflammation ◽  
Plaster Models ◽  
Abutment Screw

Screw loosening is amongst the most prevalent mechanical problems in dental implant prosthetics. Clinicians will know if the reverse Detorque values are compromised by contamination of the implant abutment screw hole either by blood , saliva or saline. Research have shown that the drying of the implant cavity may decrease the preload value when the abutment screw is closed and thereafter increase the likelihood of abutment screw loosening. Mobility of the prosthesis, or screw fracture and increase the risk of peri-implant soft-tissue inflammation. This study aims to assess and compare the effect of wet and dry fields while torqueing the abutment screws on the DE torque values. 40 Nobel bio care implant analogues mounted in plaster models were used in this study. The samples were divided into four groups dry abutment screws, artificial saliva, blood and normal saline. All the abutment screws were tightened till 20 Ncm and left aside for 15 minutes. After 15 minutes the abutment screw were DE torqued, and the DE torque values were noted for tall the groups. When analysed using paired sample t-test there was no significant difference with artificial saliva (p=0.269). There was statistical difference with blood (p=0.00) and with saline (p=0.00). Based on this study, the presence of saliva decreases the DE torque values of the abutment screws, whereas Blood and saline increase the DE torque values of the abutment screws. The presence of blood clot might be the reason for the increase in DE torque values which might decrease once the clot disintegrates. Clinicians should prevent contamination of the screw hole by blood and saliva; if contamination arises, sanitation of the infected screw and also the screw hole until final tightening is advised.

Sign in / Sign up

Export Citation Format

Share Document