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 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.

Reverse torque values of abutment screws after dynamic loading: The effects of sealant agents and the taper of conical connections

2020 ◽  
Author(s):  
Arda Ozdiler ◽  
suleyman dayan ◽  
Burc Gencel ◽  
Gulbahar Isık-Ozkol
Keyword(s):  
Dynamic Loading ◽  
Antibacterial Agent ◽  
In Vitro Study ◽  
Control Group ◽  
Silicone Sealant ◽  
Reverse Torque ◽  
The Stability ◽  
Torque Values ◽  
Chlorhexidine Gel

This in vitro study evaluated the influence of taper angles on the internal conical connections of implant systems and of the application of chlorhexidine gel as an antibacterial agent or a polyvinyl siloxane (PVS) sealant on the reverse torque values of abutment screws after dynamic loading. The current study tested four implant systems with different taper angles (5.4°, 12°, 45°, and 60°). Specimens were divided into three groups: control (neither chlorhexidine gel filled nor silicone sealed), 2% chlorhexidine gel-filled or silicone-sealed group, and group subjected to a dynamic load of 50 N at 1 Hz for 500,000 cycles prior to reverse torque measurements. Quantitative positive correlation was observed between the taper angle degree and the percentage of tightening torque loss. However, this correlation was significant only for the 60° connection groups except in the group in which a sealant was applied ( p = 0.013 for the control group, p = 0.007 for the chlorhexidine group). Percentages of decrease in the torque values of the specimens with silicone sealant application were significantly higher compared with both the control and chlorhexidine groups ( p = 0.001, p = 0.002, p = 0.001, and p = 0.002, respectively, according to the increasing taper angles); the percentage of decrease in torque values due to chlorhexidine application was statistically insignificant when compared with the control group. The application of gel-form chlorhexidine as an antibacterial agent does not significantly affect the stability of the implant–abutment connection under dynamic loads. PVS sealants may cause screw loosening under functional loads.

scholarly journals Effect of Application of a Bio-Adhesive on the Removal Torque Value and Rotational Misfit at the Implant–Abutment Junction: An In Vitro Study

Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6832
Author(s):  
Mahnaz Arshad ◽  
Sina Khayat Zadeh ◽  
Mohammad Atai ◽  
Gholamreza Shirani ◽  
Georgios E. Romanos ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Vitro Study ◽  
Control Group ◽  
Removal Torque ◽  
Cell Vitality ◽  
Implant Abutment ◽  
Measuring Machine ◽  
Adhesive Application ◽  
Abutment Screw

The aim of this study was to assess the effect of application of a recently developed bio-adhesive (Impladhesive) to abutment screw threads on the removal torque value and rotational misfit at the implant–abutment junction. This in vitro study evaluated 20 implant fixtures and 20 straight abutments. Specimens were randomly divided into two groups (n = 10) with/without adhesive application. In the adhesive group, the abutment was dipped in Impladhesive before torquing. In the control group, the abutment was torqued conventionally without adhesive application. The removal torque value was recorded after completion of the cyclic loading of 500,000 cycles with 2 Hz frequency and 75 N load. Rotational misfit was recorded using a video measuring machine. After applying the torque, the change in the bisector angle on the abutment hex was recorded for each implant. The biocompatibility of Impladhesive was evaluated using a MTT cell vitality assay. Normal distribution of data was assessed using the Kolmogorov–Smirnov test. Data were analyzed using a t-test and Pearson’s correlation coefficient The application of Impladhesive at the implant–abutment interface resulted in significantly greater mean removal torque value compared to the control group (p = 0.008). In addition, the mean rotational misfit at the implant–abutment interface was significantly lower in the use of Impladhesive compared to the control group (p = 0.001). In addition, the cell vitality was found to be greater than 80% at all evaluated time points. It can be concluded that the application of Impladhesive on the abutment screw significantly decreased rotational misfit and increased the removal torque value. Future studies are needed to evaluate the efficacy of this bio-adhesive an in vivo setting.

Dynamic and static load performance of dental biomaterial systems with conical implant-abutment connections

2020 ◽  
Vol 31 (5) ◽  
pp. 319-328
Author(s):  
Mehmet Can Basgil ◽  
Cem Kurtoglu ◽  
Koray Soygun ◽  
Yunus Uslan ◽  
Teyfik Demi̇r
Keyword(s):  
Dynamic Loading ◽  
Fracture Strength ◽  
Static Loading ◽  
Sem Analysis ◽  
Control Group ◽  
Compression Load ◽  
Implant Abutment ◽  
The Stability ◽  
Implant System

BACKGROUND: The stability of the implant-abutment interface is an important factor that influences load distribution on the marginal bone. OBJECTIVE: In this study, three dental implants with the same connection were subjected to different dynamic loading cycles. The fracture strengths and the horizontal compatibility of implants were assessed. METHODS: Eighty four implant specimens were embedded in a polyacetal cylinder as simulated bone loss of 3 mm from the implant platform. Three of the implants were used to determine the endurance limit. The other specimens were subdivided into four subgroups (n = 6): three for dynamic + static loading, and one for static loading (control group). The tests were performed by applying a compression load. The dynamic loading experiments included three different cycles with endurance upper limit loads at a frequency of 10 Hz. RESULTS: The differences between the fracture strength values of the implant brands were found to be statistically significant. However, there were no meaningful differences between the fracture strength values of implants of the same brand. The specimens of the DTI implant system had the lowest strength (647.9 ± 41.5 N) and the SEM analysis indicated that the Implantium implant system had the shortest horizontal gaps. CONCLUSIONS: There was a negative correlation between the fracture strengths and size of the microgaps. The importance of these in vitro results needs to be validated by clinical trials because the loads in the mouth can be applied from various angles.

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.

scholarly journals Evaluation of the Sealing Capability of the Internal Conical Connections of Implants with Titanium and Zirconia Abutments

2017 ◽  
Vol 18 (10) ◽  
pp. 915-922 ◽  
Author(s):  
Ilser Turkyilmaz ◽  
Damian L Black ◽  
Chol H Chong
Keyword(s):  
P Value ◽  
Colony Forming Units ◽  
Significant Difference ◽  
Implant Abutment ◽  
Level Of Significance ◽  
Torque Values ◽  
Post Hoc ◽  
Positive Controls ◽  
Abutment Screw

ABSTRACT Aim The purpose of this in vitro investigation was to evaluate the sealing capability of the conical implant–abutment interfaces under different abutment screw torque values using titanium and zirconia abutments with Morse taper designs. Materials and methods A total of 42 dental implants (n = 21 for titanium abutments and n = 21 for zirconia abutments) were inoculated internally with three bacteria. These assemblies were divided into four test groups (n = 10) based on screw fixation torques of 35 or 20 Ncm and placed in sterile broth; the remaining abutments were used as positive controls and torqued to 10 Ncm. Microleakage was quantified by enumerating the bacteria from the colony-forming units. An analysis of variance for the estimates of bacteria enumerated and microgaps was used with a post hoc analysis as indicated. A p-value of 0.05 was used as the level of significance. Results There was no statistically significant difference in microleakage among the four test groups; there were no significant effects of screw torque or abutment type on the bacteria enumerated. There was a significantly smaller mean microgap with the zirconia abutments. Conclusion The results of this study indicated no statistically significant difference in the sealing capabilities between titanium and zirconia abutments, having internal conical connections, after increasing the abutment screw torque. Clinical significance It is important for clinicians to follow the guidelines suggested by the implant companies to avoid biomechanical complications over time. How to cite this article Black DL, Turkyilmaz I, Lien W, Chong CH. Evaluation of the Sealing Capability of the Internal Conical Connections of Implants with Titanium and Zirconia Abutments. J Contemp Dent Pract 2017;18(10):915-922.

Bacterial Colonization of the Implant–Abutment Interface Using an In Vitro Dynamic Loading Model

2011 ◽  
Vol 82 (4) ◽  
pp. 613-618 ◽  
Author(s):  
Theofilos Koutouzis ◽  
Shannon Wallet ◽  
Nadia Calderon ◽  
Tord Lundgren
Keyword(s):  
Dynamic Loading ◽  
Bacterial Colonization ◽  
Implant Abutment

The Effect of Tissue Entrapment on Screw Loosening at the Implant/Abutment Interface of External- and Internal-Connection Implants: An In Vitro Study

2015 ◽  
Vol 25 (3) ◽  
pp. 216-223 ◽  
Author(s):  
Helios A. Zeno ◽  
Renan L. Buitrago ◽  
Sidney S. Sternberger ◽  
Marisa E. Patt ◽  
Nick Tovar ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Vitro Study ◽  
Screw Loosening ◽  
Internal Connection ◽  
Implant Abutment

scholarly journals Impact of Dynamic Loading on the Implant-abutment Interface Using a Gas-enhanced Permeation Test In Vitro

2015 ◽  
Vol 9 (1) ◽  
pp. 112-119
Author(s):  
Anas Al-Jadaa ◽  
Thomas Attin ◽  
Timo Peltomäki ◽  
Christian Heumann ◽  
Patrick Roger Schmidlin
Keyword(s):  
Dynamic Loading ◽  
Group Testing ◽  
Pressure Change ◽  
Leakage Resistance ◽  
Implant Abutment ◽  
Bacterial Leakage ◽  
Static Conditions ◽  
Implant System ◽  
Permeation Test

Purpose : To assess implant leakage under static conditions as well as during and after dynamic loading. Materials and methods : Implants (Astra Tech (A), Biomet 3i (B) and Nobel Biocare (C)) were evaluated for leakage (n=8/group). Testing to assess the gas pressure change over time (hPa/min) and infiltrated fluid volume, was performed in a Gas Enhanced Permeation Test (GEPT) to qualify embedding. Implant apexes were then drilled, abutments were mounted and resin build-ups were fabricated. GEPT was reassessed. Samples were afterward mounted in a computer-controlled masticator while tested to bacterial leakage, they were daily observed for turbidity. Samples were then reassessed using GEPT. Dunnett's and Fisher's exact tests were utilized to compare implant and to analyze bacterial leakage. Results : Significant differences in GEPT values were shown after loading (p=0.034). Leakage resistance was best for B when compared to C (p=0.023). Samples with higher GEPT values demonstrated earlier bacterial leakage, occurring after 1 or 2 days (A=4, B=0, C=6) and showing favorability for implant system B (p=0.009). Conclusion : Implants leaking under static conditions had increased potential for bacterial leakage under dynamic conditions. As strongly correlating to sophisticated analytical methods, GEPT is a promising technique for assessing the overall implant system leakage resistance.

scholarly journals In vitro effect of chlorhexidine gel on torque and detorque values of implant abutment screw

2017 ◽  
Vol 28 (3) ◽  
pp. 314
Author(s):  
BardiaVadiati Saberi ◽  
HamidNeshandar Asli ◽  
ArezooSadat Fatemi
Keyword(s):  
Implant Abutment ◽  
Vitro Effect ◽  
Chlorhexidine Gel ◽  
Abutment Screw
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