# Different Conical Angle Connection of Implant and Abutment Behavior: A Static and Dynamic Load Test and Finite Element Analysis Study

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## Abstract

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## 1. Introduction

## 2. Materials and Methods

#### 2.1. Instruments

#### 2.2. Static Load Test Protocol

#### 2.3. Dynamic Load Test Protocol

#### 2.4. Finite Element Analysis (FEA)

^{3}, average element quality of 0.5975, and an element volume ratio of 1.29 × 10

^{−4}, respectively.

#### 2.5. Statistical Analysis

## 3. Results

#### 3.1. Static Load Results

#### 3.2. Dynamic Load Results

#### 3.3. Finite Element Analysis

## 4. Discussion

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Fatigue machine used during the experiments and the setup of the static load test. The loading head was perpendicular to the top surface of the implant head.

**Figure 3.**Different meshing options (

**A**: coarse;

**B**: normal;

**C**: finer) and the resulting stress distribution figures.

**Figure 4.**The line defined on the conical interface in the case of a 90° connection to assess mechanical stress.

**Figure 5.**The line defined on the implant side in the case of a 90° connection to assess mechanical stress.

**Figure 6.**Results of the static load tests. Representative load-compression graphs showed differences among different conical angle implants.

**Figure 7.**Compression rate (mean ± SEM) among different conical angle implants in the static load tests.

**Figure 8.**Irreversible vertical compression rate (mean ± SEM) among different conical angle implants and abutment connections.

**Figure 9.**Resilience and energy dissipation (mean ± SEM) among different conical angle implants and abutment connections.

**Figure 10.**The mean measurements for dynamic compression force among different conical angle implants for all 15,000 cycles.

**Figure 11.**Total vertical compression (mean ± SEM) among different conical angle implants at the 15,000th cycle.

**Figure 12.**The irreversible (permanent) deformation (mean ± SEM) among different conical angle implants in the implant–abutment system after the dynamic test.

**Figure 13.**Reverse torque (mean ± SEM) needed to roll apart the implant head and implant after the fatigue test among different conical angle implants.

**Figure 14.**(

**a**–

**h**). Finite element analyses of the mechanical stresses in case of compression at 24° (

**a**–

**d**) and 90° (

**e**–

**h**) conical angle implant and abutment model geometries.

**Figure 15.**The mechanical stress distribution along the selected line on the abutment and implant connection in the case of 24° (orange) and 90° (blue) conical angles.

**Figure 16.**The mechanical stress distribution along the implant height on the side in case of 24° (orange) and 90° (blue) conical angles.

**Table 1.**Results of the post-hoc tests (p-values) during pairwise comparisons of resilience (blue) and energy dissipation (red) among different conical angle implants. p-values < 0.05 are presented in

**boldface**.

24° | 35° | 55° | 75° | 90° | |
---|---|---|---|---|---|

24° | - | 0.721 | 0.030 | 0.002 | 0.145 |

35° | 0.666 | - | 0.065 | 0.004 | 0.260 |

55° | 0.174 | 0.077 | - | 0.250 | 0.493 |

75° | 0.008 | 0.003 | 0.159 | - | 0.079 |

90° | 0.404 | 0.215 | 0.626 | 0.070 | - |

**Table 2.**Results of the post-hoc tests (p-values) during pairwise comparisons of mean vertical compressions among different conical angle implants. p-values < 0.05 are presented in

**boldface**.

24° | 35° | 55° | 75° | 90° | |
---|---|---|---|---|---|

24° | - | ||||

35° | 0.234 | - | |||

55° | 0.204 | 0.932 | - | ||

75° | 0.141 | 0.011 | 0.009 | - | |

90° | 0.490 | 0.065 | 0.055 | 0.422 | - |

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## Share and Cite

**MDPI and ACS Style**

Körtvélyessy, G.; Szabó, Á.L.; Pelsőczi-Kovács, I.; Tarjányi, T.; Tóth, Z.; Kárpáti, K.; Matusovits, D.; Hangyási, B.D.; Baráth, Z.
Different Conical Angle Connection of Implant and Abutment Behavior: A Static and Dynamic Load Test and Finite Element Analysis Study. *Materials* **2023**, *16*, 1988.
https://doi.org/10.3390/ma16051988

**AMA Style**

Körtvélyessy G, Szabó ÁL, Pelsőczi-Kovács I, Tarjányi T, Tóth Z, Kárpáti K, Matusovits D, Hangyási BD, Baráth Z.
Different Conical Angle Connection of Implant and Abutment Behavior: A Static and Dynamic Load Test and Finite Element Analysis Study. *Materials*. 2023; 16(5):1988.
https://doi.org/10.3390/ma16051988

**Chicago/Turabian Style**

Körtvélyessy, Győző, Árpád László Szabó, István Pelsőczi-Kovács, Tamás Tarjányi, Zsolt Tóth, Krisztina Kárpáti, Danica Matusovits, Botond Dávid Hangyási, and Zoltán Baráth.
2023. "Different Conical Angle Connection of Implant and Abutment Behavior: A Static and Dynamic Load Test and Finite Element Analysis Study" *Materials* 16, no. 5: 1988.
https://doi.org/10.3390/ma16051988