Stress Evaluation of Implant-Abutment Connections Under Different Loading Conditions: A 3D Finite Element Study

This study evaluated the effects of axial and oblique occlusal loading on implant-supported partial dentures with different connection systems (external hexagon, internal hexagon, and Morse taper). Upon axial loading, all systems presented similar stress values. Stress values increased under oblique loading. Stress distribution changed for some of the internal connection structures. It can be concluded that oblique load increases stress on bone structures and prosthetic components. Internal connection system implants present more favorable stress distribution patterns than do external connection system implants.

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The biomechanical behavior of single crown implant-supported prosthesis with different types of connections and occlusal loads: Photoelastic and strain gauge analysis

Research Society and Development ◽

10.33448/rsd-v10i9.18035 ◽

2021 ◽

Vol 10 (9) ◽

pp. e26110918035

Author(s):

Caroline de Freitas Jorge ◽

Letícia Cerri Mazza ◽

Marcio Campaner ◽

Abbas Zahoui ◽

Lorena Scaioni Silva ◽

...

Keyword(s):

Stress Distribution ◽

Strain Gauge ◽

High Intensity ◽

Axial Load ◽

The Other ◽

Biomechanical Behavior ◽

Single Crown ◽

Different Types ◽

Connection System ◽

Oblique Load

The aim of the study was to evaluate the biomechanical behavior, through photoelastic (PA) and strain gauge analysis (SA), of single crown implant-supported prosthesis with different implant connections (external hexagon (EH), Morse taper (MT), internal Morse hexagon (IMH), Morse taper hexagon (MTH), and frictional Morse taper (FMT)) and different occlusal loads (axial and oblique (45°)). The data were submitted to ANOVA and Tukey's test (α = 0,05). By photoelasticity, regarding axial load, EH produced more high-intensity fringes (2.784 kPa) than the other connections. For the oblique load, all connections generated the same high-intensity fringes (3.480 kPa), except by MT group, that produced the same amount as axial load (2.088 kPa). For the strain gauge analysis, for the axial load, EH showed the highest microstrains value (158,76) and lowets for MT (59,88). For all other groups, oblique load produced higher microstrains values than axial load. For the oblique load, MT showed the lowest microstrains value (88.79), followed by FMT (391,43), EH (468,47) and IMH (507,65). MTH presented the highest value (621,25) compared to all groups (P <0.05). When comparing both loads of the same connection system, only MT showed similar values (P <0.05). It was possible to conclude that the different connection systems tested directly influenced the stress distribution at both loads. The implants with internal connection present less stress distribution when submitted to axial load than the EH group. However, when the oblique load was applied, all connections presented higher values of stress distribution, except for the MT group.

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Comparison of stress distribution in a three unit cement retained implant supported prosthesis with different implant abutment connections: A photoelastic analysis

RGUHS Journal of Dental Sciences ◽

10.26715/rjds.12_1_8 ◽

2020 ◽

Vol 12 (1) ◽

pp. 35-43

Author(s):

Dr Poojya R ◽

Dr Darakshan Nazir ◽

Dr Shruthi C S

Keyword(s):

Stress Distribution ◽

Axial Loading ◽

The Body ◽

Partial Denture ◽

Fixed Partial Denture ◽

Group I ◽

Significant Difference ◽

Implant Abutment ◽

Oblique Loading ◽

Group Ii

Aim: With the emphasis on success of implant supported prosthesis, and health of the surrounding tissues that are related to accuracy, and fit between the implant components, stability at implant abutment interface is of prime importance. The aim of this study is to evaluate and compare the stress distribution in three unit cement retained implant supported fixed partial denture with different implant abutment connections through photo elasticity. Materials and methods: Two photo elastic resin models were fabricated of standard dimensions (44mmx22mmx10mm). Group I sample: Three unit cement retained implant supported fixed partial denture with Internal implant abutment connection (Internal hexagonal connection) (Paltop Advanced, Keystone Dental Company, US)Group II sample: Three unit cement retained implant supported fixed partial denture with conical Morse taper connection (1.5 degree Morse taper) (Paltop Conical Active, Keystone Dental Company, US). Three unit cement retained implant supported fixed partial denture simulated missing mandibular first molar. Axial and oblique loads of 100N were placed on each implant and pontic area for 10 sec. Ten tests were done for each group. The stress values around the implants were derived from the colored fringe patterns obtained through polariscope, which were photographed after load applications from which values were derived. Results: Under axial loading, there was statistically significant difference between internal hexagonal connection and Morse taper connection in three unit implant supported prosthesis. Stresses were more in Group II sample with Morse taper connection. Under oblique loading, there was no statistically significant difference between Group I and Group II samples. Conclusion: Within the limitations of this in vitro study, it can be concluded that Internal hexagonal connection showed less stresses as compared to Morse taper connection in a three unit cement retained implant supported prosthesis. Stresses were concentrated more in apical area under axial loading; while under oblique loading stresses were seen on the side of application of force on the body of the implant and on the apical region. However, stresses were uniformly distributed in both groups I and group II samples. In both groups stresses under oblique loading were more than axial loading, but that was not statistically significant.

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Influence of Connection Type and Platform Diameter on Titanium Dental Implants Fatigue: Non-Axial Loading Cyclic Test Analysis

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17238988 ◽

2020 ◽

Vol 17 (23) ◽

pp. 8988

Author(s):

Ana I. Nicolas-Silvente ◽

Eugenio Velasco-Ortega ◽

Ivan Ortiz-Garcia ◽

Alvaro Jimenez-Guerra ◽

Loreto Monsalve-Guil ◽

...

Keyword(s):

Dental Implants ◽

Axial Loading ◽

Test Analysis ◽

Load Limit ◽

Implant Abutment ◽

Connection Type ◽

Number Of Cycles ◽

Oblique Load ◽

Titanium Dental Implants

Two-pieces dental implants must provide stability of the implant-abutment-interface. The connection type and platform diameter could influence the biomechanical resistance and stress distribution. This study aims to evaluate the fatigue for different types of connections, external and internal, and different platform diameters. Three implant designs with the same length were used: (a) external hexagon/narrow platform; (b) internal double hexagon/narrow platform; (c) internal octagon/regular platform. A fatigue test was developed to establish the number of cycles needed before fracture. A 30º oblique load with a sinusoidal function of fatigue at a frequency of 15 Hz and 10% stress variation was applied to each system. The fatigue load limit (FLL) for design (a) was 190 N, being the nominal-curvature-moment (NCM) = 1.045; FLL = 150 N, with a NCM = 0.825 for (b), and FLL = 325 N, with a NCM = 1.788 for (c). The platform diameter affects the FLL, obtaining lower FLL on a narrow platform. The connection type interferes with the implant walls’ width, especially in narrow implants, making internal connections more unstable at this level. Long-term clinical studies to assess the restoration’s success rate and survival are mandatory.

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How Do Differences of Dental Implants’ Internal Connection Systems Affect Stress Distribution? A 3-Dimensional Finite Element Analysis

Balkan Journal of Dental Medicine ◽

10.2478/bjdm-2019-0023 ◽

2019 ◽

Vol 23 (3) ◽

pp. 126-131

Author(s):

Özge Özdal Zincir ◽

Gökay Karapinar ◽

Meral Ünür ◽

Ahmet Bülent Katiboğlu

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Stress Distribution ◽

Dental Implants ◽

Element Analysis ◽

Significant Difference ◽

Implant Abutment ◽

Connection System ◽

Different Diameters ◽

Stress Accumulation

Summary Background/Aim: A factor affecting the success rate of dental implants, which has been used successfully for many years, is the implant-abutment connection system. The purpose of this study was to evaluate the stress distribution of different implant-abutment connection systems under different forces. Material and Methods: This in vitro study included a finite element analysis. In the study, the cylindrical and screwed dental implants available in 3 different diameters from 4 different companies were categorized into 12 different models. Two different scenarios of force application were conducted on each model in this study. In the first scenario, 100 N force and 100 N moment were applied in a vertical direction onto a point considered as the center of each tooth. In the second scenario, a 100 N force and moment were applied at a 45° angle in an oblique direction. Results: As a result of the forces applied to dental implants of different diameters from different companies, octagon implant-abutment connection systems had less stress accumulation than hexagon implant-abutment connection systems. In addition, when stress accumulation ratios were evaluated according to the diameter of the implants used, it was observed that 3 mm diameter implants accumulated more stress in bone than 4 mm diameter implants; there was no significant difference between 4 mm diameter implants and 5 mm diameter implants. Conclusions: Implant-abutment connection system is important for the longevity of implants under the forces. Therefore, this factor should be considered during implant selection.

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Effects of different implant–abutment connections on micromotion and stress distribution: Prediction of microgap formation

Journal of Dentistry ◽

10.1016/j.jdent.2012.02.009 ◽

2012 ◽

Vol 40 (6) ◽

pp. 467-474 ◽

Cited By ~ 58

Author(s):

Syafiqah Saidin ◽

Mohammed Rafiq Abdul Kadir ◽

Eshamsul Sulaiman ◽

Noor Hayaty Abu Kasim

Keyword(s):

Stress Distribution ◽

Implant Abutment

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

Journal of Prosthodontics ◽

10.1111/jopr.12329 ◽

2015 ◽

Vol 25 (3) ◽

pp. 216-223 ◽

Cited By ~ 6

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

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Stress-Distribution Pattern Across the Glenohumeral Joint in Collegiate and Professional Baseball Players: A Computed Tomography Osteoabsorptiometry Study

Orthopaedic Journal of Sports Medicine ◽

10.1177/23259671211009185 ◽

2021 ◽

Vol 9 (6) ◽

pp. 232596712110091

Author(s):

Kyosuke Numaguchi ◽

Daisuke Momma ◽

Yuki Matsui ◽

Masashi Yokota ◽

Jun Oohinata ◽

...

Keyword(s):

Bone Density ◽

Stress Distribution ◽

Glenohumeral Joint ◽

Distribution Patterns ◽

Joint Surface ◽

Baseball Players ◽

Articular Surfaces ◽

Head Surface ◽

The Mean ◽

Dominant Side

Background: The influence of long-term loading conditions on the articular surfaces of the glenohumeral joint can be determined by measuring stress-distribution patterns. Long-term pitching activity changes the stress distribution across the glenohumeral joint surface; however, the influence of competitive level on stress-distribution patterns remains unclear. Purpose: To use computed tomography (CT) osteoabsorptiometry (CTOAM) to evaluate the distribution of subchondral bone density across the glenohumeral joint in collegiate and professional baseball players as well as to determine the effects of pitching activity on the articular surfaces. Study Design: Descriptive laboratory study. Methods: We evaluated 73 shoulders in 50 baseball players. CT imaging data were obtained from the dominant-side shoulder of 12 professional pitchers (PP group) and 15 professional fielders (PF group). CT imaging data were also obtained from both shoulders of 12 asymptomatic collegiate pitchers (CP group) and 11 collegiate fielders (CF group). The pattern of distribution of subchondral bone density across the articular surfaces of each glenohumeral joint was assessed by CTOAM. As a measure of bone density, the mean Hounsfield units (HU) were obtained for each joint surface, and the absolute values of the dominant shoulder were compared for each group. Results: Stress-distribution patterns over the articular surfaces differed between the dominant and nondominant sides in the CP group as well as between both collegiate groups versus the PP group. In the CP group, the mean HU of the humeral head surface were greater on the nondominant versus dominant side ( P = .035). On the dominant side, the mean HU of the humeral head surface and glenoid were greater in the CP versus the PP group ( P = .001 and .027, respectively). Conclusion: Stress distribution on the articular surface of the glenohumeral joint was affected by pitching ability and competitive level. Our analysis indicates that the traction force on the glenohumeral joint surface might be greater than compression force during pitching. Clinical Relevance: The present findings suggest that pitching activity results in low stress to the articular surfaces of the glenohumeral joint. This supports the notion that mechanical conditions play a crucial role in the etiology of disorders specific to pitching activity.

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Residual Stress Evaluation of Dissimilar Weld Joint Using Reactor Vessel Outlet Nozzle Mock-Up Model (Report-1)

Volume 6: Materials and Fabrication, Parts A and B ◽

10.1115/pvp2008-61829 ◽

2008 ◽

Cited By ~ 10

Author(s):

Itaru Muroya ◽

Youichi Iwamoto ◽

Naoki Ogawa ◽

Kiminobu Hojo ◽

Kazuo Ogawa

Keyword(s):

Residual Stress ◽

Stress Distribution ◽

Welding Process ◽

Reactor Vessel ◽

Residual Stress Distribution ◽

Test Model ◽

Alloy 600 ◽

Outlet Nozzle ◽

Stress Evaluation ◽

Weld Region

In recent years, the occurrence of primary water stress corrosion cracking (PWSCC) in Alloy 600 weld regions of PWR plants has increased. In order to evaluate the crack propagation of PWSCC, it is required to estimate stress distribution including residual stress and operational stress through the wall thickness of the Alloy 600 weld region. In a national project in Japan for the purpose of establishing residual stress evaluation method, two test models were produced based on a reactor vessel outlet nozzle of Japanese PWR plants. One (Test model A) was produced using the same welding process applied in Japanese PWR plants in order to measure residual stress distribution of the Alloy 132 weld region. The other (Test model B) was produced using the same fabrication process in Japanese PWR plants in order to measure stress distribution change of the Alloy 132 weld region during fabrication process such as a hydrostatic test, welding a main coolant pipe to the stainless steel safe end. For Test model A, residual stress distribution was obtained using FE analysis, and was compared with the measured stress distribution. By comparing results, it was confirmed that the FE analysis result was in good agreement with the measurement result. For mock up test model B, the stress distribution of selected fabrication processes were measured using the Deep Hole Drilling (DHD) method. From these measurement results, it was found that the stress distribution in thickness direction at the center of the Alloy 132 weld line was changed largely during welding process of the safe end to the main coolant pipe.

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