scholarly journals Effect of Abutment Type and Tightening Sequence on Torque Maintenance Capacity after Mechanical Cycling in Splinted Implant-Supported Restorations

Oral ◽  
2021 ◽  
Vol 1 (4) ◽  
pp. 300-306
Author(s):  
Leonardo Jiro Nomura Nakano ◽  
Laís Carolina Landim Gomes ◽  
Talita Suelen de Queiroz ◽  
Tarcisio José de Arruda Paes-Junior
Keyword(s):  
Fatigue Test ◽  
Cobalt Chromium ◽  
Removal Torque ◽  
Tukey Test ◽  
Mechanical Cycling ◽  
Torque Wrench

The aim of this study was to compare the screw removal torque of mini-conical prosthetic components and straight trunnion of indexed morse taper implants after mechanical cycling. The sample consisted of 40 implants and 20 mini-conical prosthetic components (MC group) and 20 straight trunnion components (ST group). Each group consisted of 10 specimens, with 2 implants in each, and cobalt–chromium metallic crowns were screwed into each sample. The components of the MC group received a torque of 20 N-cm with a digital torque wrench, and after 10 min were retightened with the same value as the initial torque. The components of the ST group received a torque of 30 N-cm, with a digital torque wrench, and after 10 min, they were retightened with the same value. The screws of the respective crowns of the two groups received a torque of 10 N-cm and after 10 min were retightened with the same value. Each group was subjected to the fatigue test in a mechanical cycler at 2,000,000 cycles, with a load of 250 N and frequency of 4 Hz. At the end of the fatigue test, the loosening torque of each screw of the specimens was measured through a digital torque wrench. The data were analyzed by two-way ANOVA and a Tukey test. In both groups, there were loss of torque. The results showed no statistic difference between MC and ST groups (p > 0.05).

scholarly journals Effect of Abutment Type and Tightening Sequence on Torque Maintenance Capacity after Mechanical Cycling in Splinted Implant-Supported Restorations

2021 ◽  
Author(s):  
Leonardo Jiro Nomura Nakano ◽  
Laís Carolina Landim Gomes ◽  
Talita Suelen de Queiroz ◽  
Tarcisio José de Arruda Paes-Junior
Keyword(s):  
Fatigue Test ◽  
Cobalt Chromium ◽  
Removal Torque ◽  
Tukey Test ◽  
Mechanical Cycling ◽  
Torque Wrench

The aim of this study was to compare the screw removal torque of mini conical prosthetic components and straight trunnion of indexed morse taper implants, after mechanical cycling. The sample consisted of 40 implants and 20 mini-conical prosthetic components (MC group) and 20 straight trunnion components (ST group). Each group consisted of 10 specimens, with 2 implants in each, and cobalt-chromium metallic crowns were screwed into each sample. The components of the MC group received a torque of 20 N.cm with a digital torque wrench and after 10 minutes were retightened with the same value as the initial torque. The components of the ST group received a torque of 30 N.cm, with a digital torque wrench and after 10 minutes, they were retightened with the same value. The screws of the respective crowns of the two groups received a torque of 10 N.cm and after 10 minutes were retightened with the same value. Each group was subjected to the fatigue test in a mechanical cycler at 2.000.000 cycles, with a load of 250 N and frequency of 4 Hz. At the end of the fatigue test, the loosening torque of each screw of the specimens was measured through a digital torque wrench. The data were analyzed by two-way ANOVA and Tukey test. In both groups, there were loss of torque. The results showed no statistic difference between MC and ST groups.

scholarly journals Effect of Mechanical Cycling on Screw Torque in External Hexagon Implants with and without Platform Switching

2015 ◽  
Vol 26 (3) ◽  
pp. 284-287 ◽  
Author(s):  
Bruno Andrade Cantharino de Carvalho ◽  
Eduardo Vedovatto ◽  
Paulo Sérgio Perri de Carvalho ◽  
José Vitor Quinelli Mazaro ◽  
Rosse Mary Falcón-Antenucci
Keyword(s):  
In Vitro Study ◽  
Screw Loosening ◽  
Removal Torque ◽  
Tukey Test ◽  
Reverse Torque ◽  
Mechanical Cycling ◽  
Significant Difference ◽  
Platform Switching ◽  
Abutment Screw

This in vitro study evaluated the effect of mechanical cycling on the torque of retaining screw in external hexagon implants with platform switching (PS), regular platform (RP) and wide platform (WP). A total of 30 specimens were equally divided into 3 groups: PS, PR and WP. Each specimen was prepared with implants: 3.75 x 10 mm for RP group and 5.0x10 mm for PS and WP groups and its respective abutment with 32 Ncm torque. All groups were subjected to 106 cycles with 100 N (corresponding to about 40 months of chewing). The results were obtained with the reverse torque of each specimen and data were evaluated using ANOVA and Tukey test (p<0.05). The PS group showed statistically significant difference in screw removal torque (30.06±5.42) compared with RP (23.75±2.76) and WP (21.32±3.53) (p<0.05) groups; the RP and WP groups showed no statistically significant difference between them. It was concluded that the PS group showed higher reverse torque value, suggesting lower susceptibility of the abutment screw loosening.

scholarly journals Stability of external and internal implant connections after a fatigue test

2013 ◽  
Vol 07 (03) ◽  
pp. 267-271 ◽  
Author(s):  
Paulo Cesar Pinheiro Feitosa ◽  
Ana Paula Barbosa de Lima ◽  
Laís Regiane Silva-Concílio ◽  
William Cunha Brandt ◽  
Ana Christina Claro Neves
Keyword(s):  
Mechanical Testing ◽  
Fatigue Test ◽  
Analysis Of Variance ◽  
Mechanical Cycling ◽  
Before And After ◽  
Lower Variation

ABSTRACT Objective: The objective of this study was to compare the torque and detorque values of screw intermediates of external hexagon, internal hexagon, and Morse taper implants in single restorations before and after mechanical cycling. Materials and Methods: The study sample was divided into three groups (n = 10) as follows: group EH - external hexagon implant, group IH - internal hexagon implant, and group MT - Morse taper implant. Universal abutments were screwed on the implants, and metal crowns were cemented onto the abutment. The samples were submitted to a mechanical testing of 1 million cycles, with a frequency of 8 cycles per second under a 400 N load. The application and registration of the screw torque (T0) and detorque (T1) values of the intermediate were performed before and after the test. The results were statistically evaluated by analysis of variance (ANOVA) and Tukey′s test (α = 0.05). Results: There was no difference between the values of T0 and T1 in the intra-group samples. However, the inter-group difference in T0 between the EH (12.8 N cm) and MT (18.6 N cm) groups and in T1 between the EH (10.4 N cm) and IH (13.8 N cm), EH and MT (19.4 N cm), and MT and IH (P = 0.001) groups were significant. The MT group showed a lower variation of T0 and T1. Conclusion: The internal implants, particularly MT, showed better stability in these cases when used for single restorations.

Removal Torque Analysis of Implants in Rabbit Tibia After Topical Application of Simvastatin Gel

2014 ◽  
Vol 40 (1) ◽  
pp. 53-59 ◽  
Author(s):  
Fatima Neves Faraco-Schwed ◽  
Luiz Macedo Mangueira ◽  
Joao Vitor Albuquerque Ribeiro ◽  
Alexsandro Da Silva Antao ◽  
Jamil Awad Shibli
Keyword(s):  
Topical Application ◽  
Topical Administration ◽  
Titanium Implants ◽  
Removal Torque ◽  
Implant Placement ◽  
Group I ◽  
Torque Wrench ◽  
Rabbit Tibia ◽  
Torque Analysis ◽  
Torque Values

The aim of this study was to evaluate the effects of topical application of simvastatin gel (7.5 mg) on the removal torque of titanium implants in the rabbit tibia. A total of 32 surgeries were performed on 16 New Zealand rabbits for the placement of 2 implants in 1 tibia of each rabbit. Only 1 of the surgical defects was injected with 30 mg/mL of simvastatin gel before implant placement. The initial torque was set at 20 N.cm, and removal torque testing was performed 28 and 56 days postoperatively with a Tonishi torque wrench. Surgical defects were divided into 4 groups: group IG-28 (test, 28 days), group IG-56 (test, 56 days), group I-28 (control, 28 days), and group I-56 (control, 56 days). Removal torque values were higher in group IG-56 than in groups IG-28, I-28, and I-56 (P &lt; .05). Groups IG-28, I-28, and I-56 showed similar values (P &gt; .05). Removal torque force increased under the influence of simvastatin, indicating that topical administration of a 7.5-mg dose of simvastatin gel is effective in improving the torque force required to remove implants inserted in the rabbit tibia.

scholarly journals Implant Volume Loss, Misfit, Screw Loosening, and Stress In Custom Titanium and Zirconia Abutments

2020 ◽  
Vol 31 (4) ◽  
pp. 374-379
Author(s):  
Sales Antônio Barbosa Jr ◽  
Ataís Bacchi ◽  
Valentim Adelino Ricardo Barão ◽  
Yara Teresinha Corrêa Silva-Sousa ◽  
João Felipe Bruniera ◽  
...  
Keyword(s):  
Stress Distribution ◽  
Repeated Measures ◽  
Titanium Implants ◽  
Volume Loss ◽  
Screw Loosening ◽  
Mechanical Cycling ◽  
Torque Wrench ◽  
Significant Difference ◽  
Before And After ◽  
Cad Cam

Abstract The aim of this study was to verify the effect of the implant volume loss, vertical misfit between abutment and prosthetic platform, prosthetic screw loosening torque, and screw stress distribution in titanium and zirconia abutments. Ten CAD/CAM system custom abutments of each material were milled and attached to the titanium implants. The implant volume loss was evaluated by microtomography, the vertical misfit with optical microscopy, and digital torque wrench measured the prosthetic screw loosening. All experimental analyses were performed before and after mechanical cycle (1,000,000 cycles, 100 N/2 Hz). Virtual models of the structures were created for finite element analysis, and the stress on the screw obtained with von Mises procedure. Data were analyzed using an independent t-test, two-way ANOVA for repeated measures, and Tukey’s HSD test (a=0.05). There was no significant difference in the implant volume loss for the two abutment materials (p=0.662). Titanium abutments provided higher loosening torque values after mechanical cycling (p<0.001). Lesser marginal misfit was obtained with titanium abutments before and after mechanical cycling (p<0.001). The stress distribution on the screw was similar between abutment materials. In conclusion, CAD/CAM custom titanium abutment reduced the marginal misfit and increased the torque maintenance of prosthetic screws when compared to CAD/CAM custom zirconia abutment.

scholarly journals EFFECT OF ANGLED INSTALLATION OF ORTHODONTIC MINI-IMPLANTS ON PRIMARY STABILITY

2014 ◽  
Vol 2 (2) ◽  
pp. 169
Author(s):  
Fabiana Padovan Di Lello ◽  
Flávia Regina Vergamine Salles Sgarbi ◽  
Eloisa Marcantonio Boeck ◽  
Nadia Lunardi ◽  
Rodolfo Jorge Boeck Neto
Keyword(s):  
Bone Density ◽  
Cortical Bone ◽  
Primary Stability ◽  
Insertion Torque ◽  
Medullary Bone ◽  
Removal Torque ◽  
Synthetic Bone ◽  
Whitney Test ◽  
Mini Implants ◽  
Torque Wrench

AIM: The aim of this work was evaluate the insertion and removal torque for orthodontic mini-implants inserted in different inclination. MATERIALS AND METHODS: Ten self-drilling mini-implants from the brand SIN (Sistema de Implantes Nacional, São Paulo/SP, Brazil), and the surgical kit for their insertion were used. Two plaques of synthetic bone of 120 mm x 170 mm x 41,5 mm were used (Sawbones, Pacific Research Laboratories Inc, Vashon, Wash), with 1,5 mm height, simulating the cortical bone (density 40 pcf) and 40 mm simulating the medullary bone (density 15 pcf). In each block, five areas were demarcated for each mark, totalizing ten areas. The ten mini-implants were inserted by the same operator, previously calibrated; five of them at 900 and five at 600, using the manual key kit. After the insertion of all the mini-implants, the final threading and the reading of insertion torque value were carried out with a manual torque wrench digital Lutron TQ-8800 (Lutron Electronic Enterprise Co., Ltd, Taipei, Taiwan) until the trans-mucosal profile achieve the cortical bone. The maximum insertion torque value was registered in N/cm. After all the implants inserted, the measurement of removal torque was started, performed in the same way of insertion, but in the opposite anticlockwise. The results were submitted to the T test (parametric) and to a Mann-Whitney test (non-parametric). RESULTS: The results demonstrated that the insertion torque was lower than the removal one in both insertion degrees, with statistically significance. Despite insertion torque at 90 degrees had been lightly higher than that inserted at 60 degrees, they were not statistically significant. CONCLUSION: In view of the results, it was possible conclude that insertion at 60º angulation does not offer advantages to the primary stability for orthodontic mini-implants.

scholarly journals Evaluation of screw loosening on new abutment screws and after successive tightening

2011 ◽  
Vol 22 (1) ◽  
pp. 51-55 ◽  
Author(s):  
Gustavo Seabra Barbosa ◽  
João Paulo da Silva-Neto ◽  
Paulo Cezar Simamoto-Júnior ◽  
Flávio Domingues das Neves ◽  
Maria da Gloria Chiarello de Mattos ◽  
...  
Keyword(s):  
Chromium Alloy ◽  
Screw Loosening ◽  
Cobalt Chromium ◽  
Torque Wrench ◽  
Significant Difference ◽  
Loss Data ◽  
Torque Loss ◽  
First Moment ◽  
Cobalt Chromium Alloy

This study evaluated the loss of the torque applied after use of new screws and after successive tightening. Four infrastructures (IE), using UCLA castable abutment type, were cast in cobalt-chromium alloy and new abutment screws (G1) were used in a first moment. Subsequently, the same abutment screws were used a second time (G2) and more than two times (G3). The values of the torques applied and detorques were measured with a digital torque wrench to obtain the values of initial tightening loss (%). Data were analyzed by ANOVA and Tukey's test (?=0.05). Significant differences were observed between the G1 (50.71% ± 11.36) and G2 (24.01% ± 3.33) (p=0.000) and between G1 (50.71% ± 11.36) and G3 (25.60% ± 4.64) (p=0.000). There was no significant difference between G2 and G3 (p=0.774). Within the limitations of the study, it may be concluded that the percentage of the initial torque loss is lower when screws that already suffered the application of an initial torque were used, remaining stable after application of successive torques.

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