Next Article in Journal
Study on Expansion Rate of Steel Slag Cement-Stabilized Macadam Based on BP Neural Network
Previous Article in Journal
Effects of Resting Conditions on Tensile Properties of Acid Aggregate Hydraulic Asphalt Concrete
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Materials
Volume 17
Issue 14
10.3390/ma17143557
materials-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Investigation of the Mechanical Strength of Artificial Metallic Mandibles with Lattice Structure for Mandibular Reconstruction

by
Shinsuke Kawamata
1,
Tadashi Kawai
1,*,
Erika Yasuge
1,
Isao Hoshi
1,
Tadaharu Minamino
2,
Shingo Kurosu
2 and
Hiroyuki Yamada
1
1
Division of Oral and Maxillofacial Surgery, School of Dentistry, Iwate Medical University, 19-1, Uchimaru, Morioka 020-8505, Iwate, Japan
2
Department of Elementary Material Process Technology, Iwate Industrial Research Institute, 2-4-25, Kitaiioka, Morioka 020-0857, Iwate, Japan
*
Author to whom correspondence should be addressed.
Materials 2024, 17(14), 3557; https://doi.org/10.3390/ma17143557
Submission received: 1 July 2024 / Revised: 14 July 2024 / Accepted: 16 July 2024 / Published: 18 July 2024
Browse Figures
Versions Notes

Abstract

:
Mandibular reconstructive surgery is necessary for large bone defects. Although various reconstruction methods have been performed clinically, there is no mandibular reconstruction method that meets both sufficient strength criteria and the patient’s specific morphology. In this study, the material strength of the cylindrical lattice structures formed by electron-beam melting additive manufacturing using titanium alloy powder was investigated for mandibular reconstruction. The virtual strengths of 28 lattice structures were compared using numerical material tests with finite element method software. Subsequently, to compare the material properties of the selected structures from the preliminary tests, compression test, static bending test and fatigue test were conducted. The results showed that there were correlations with relative density and significant differences among the various structures when comparing internal stress with deformation, although there was a possibility of localized stress concentration and non-uniform stress distribution based on the lattice structure characteristics. These results suggest that the lattice structure of body diagonals with nodes and a cell size of 3.0 mm is a potential candidate for metallic artificial mandibles in mandibular reconstruction surgery.

1. Introduction

In oral and maxillofacial surgery, mandibular reconstruction is frequently performed in conjunction with surgery for tumors, inflammation, or fractures [1,2,3]. Free vascularized bone grafting is a major mandibular reconstruction method that is commonly performed in current clinical practice [4]. However, it has the disadvantage of being highly invasive [5]. Therefore, mandibular reconstruction using iliac particulate cancellous bone and marrow with a titanium mesh tray has been proposed as an alternative [6]. However, the risk of infection at the bone harvest site and material problems, such as fatigue-induced breakage of the titanium mesh tray, remain unsolved [7]. To solve these problems, titanium mesh trays have been fabricated by metal additive manufacturing methods with computer-aided design data using selective laser melting technology or electron-beam melting technology [8,9]. Custom-made mesh trays that account for the morphology of the mandible and occlusal force have been developed [10].
Artificial custom-made metal bones produced by additive manufacturing methods have been applied in the orthopedic field as a bone substitute [11,12]. However, the material conditions for application to the legs and arms that bear high loads remain unclear [13]. The lattice structure has a periodic cell structure that is expected to be highly rigid and lightweight, and it is also used in the aerospace field [14,15]. Unit cell structures, such as tetrahedrons, cubes, and gyroids, are used as porous artificial bone-substitute materials in medical experiments [16,17]. The periodic size of the unit cell structure affects porosity and mechanical strength [18]. However, there are few experimental reports on lattice-structured objects fabricated using metal additive manufacturing. Although another group reported the osteogenic and angiogenic abilities of a titanium alloy scaffold fabricated by metal additive manufacturing with bone marrow mesenchymal stem cells and vascular endothelial progenitor cells in rabbit femurs [19], this study focused on the adhesion and proliferation of cells on the scaffold and did not evaluate the mechanical strength of the scaffold; therefore, its effectiveness for large bone defects that are subject to load bearing was not indicated. Another study measured the mechanical strength of a cubic titanium lattice structure fabricated by metal additive manufacturing [20,21,22]. However, this study only investigated the cubic lattice structure and did not compare it with other structures. No studies have evaluated the morphology and function of multiple lattice structures to determine the optimal type and structure of metal materials with lattice structures that can be used as human bone substitutes.
To develop a new mandibular reconstruction method that does not rely on autologous bone grafting, this study aimed to investigate the conditions for a bone-substitute material with an optimal lattice structure fabricated by additive manufacturing with sufficient strength to withstand clinical applications.

2. Materials and Methods

2.1. Selection of Lattice Structures

This study analyzed 28 types of lattice structures included in the finite element analysis software (ANSYS Multiscale. Sim® 2021 R1, Cybernet Systems Co., Ltd., Tokyo, Japan), which are often used in engineering. A numerical material test was performed by predicting the virtual material property values of each lattice structure using ANSYS Multiscale. Sim® 2021 R1. The sample conditions of the simulation included a Young’s modulus of 120 MPa, which was the condition value of the material used for the specimen preparation, and a size of 30 × 30 × 30 mm. The correlation between the equivalent physical properties and the relative density of the structure was evaluated. The evaluation criteria were an elastic modulus similar to that of cortical bone (Young’s modulus 10–30 GPa) [23], a maximum bite force of 2000 N [24], and a fatigue strength that could withstand 6.7 million chewing cycles over 10 years [25]. Three lattice structures were selected based on the analysis for the preparation of specimens.

2.2. Preparation of Specimens

The specimens were designed using computer-assisted design software (Materialise Magics 27, Materialize, Leuven, Belgium) and prepared using an electron-beam manufacturing system (Arcam EBM AX2; General Electric Company, Boston, MA, USA). Ti-64 grade 23 D50 (AP&C, Boisbriand, QC, Canada). Titanium alloy powder with a particle size of 45–106 mm and an average particle size of 70 mm was used for this study. The standard recipe recommended by the equipment manufacturer was used to determine the molding conditions for the specimens.

2.3. Compression Test

Because standards for specimens with lattice structures have not yet been established, the Japanese JIS T 0309 [26], 0312 [27], or 0313 [28] standards are referred to as the standard. Multiple lattices were arranged side by side on the load-bearing cross-section so that the multiple lattices could exhibit mechanical properties as aggregates. Each specimen was prepared in a cylindrical shape with a diameter of 6 mm and height of 10 mm. Three types of unit cell sizes (3, 4, and 5 mm) were prepared for the three selected lattice structures. An Instron 8874 mechanical testing system (Instron, Norwood, MA, USA) was used for the compression tests. The cylindrical specimens were compressed in the long-axis direction with the melting surface set as the bottom surface. The test speed (V: mm/min) was set as follows, V = ah × 60 = 10−3 × 10 mm × 60 = 0.6 mm/min ≒ 1.0 mm/min, where a was a strain rate of 10−3/s and h was a specimen height of 10 mm. From the stress–strain curve obtained, the 0.2% offset load was evaluated under the condition of 0.05 mm for the offset displacement corresponding to a 0.2% displacement. Five specimens were prepared from each group and evaluated.

2.4. Static Bending Test

Each specimen was prepared in a cylindrical shape with a diameter of 6 mm and a height of 50 mm. Three types of unit cell sizes (3, 4, and 5 mm) were prepared for the three selected lattice structures. An Instron 8874 mechanical testing system was used in this study. A three-point bending test was also conducted. The distance between the loading and supporting rollers was set to 25 mm, and the diameters of the loading and supporting rollers were 10 and 4 mm, respectively. From the obtained load–displacement curve, the 0.2% offset load was evaluated under the condition of 0.05 mm for the offset displacement corresponding to a 0.2% displacement. Five specimens were prepared from each group and evaluated.

2.5. Fatigue Test

Dumbbell-shaped specimens were used for the fatigue test. The specimen was gripped on both sides, and the test was performed on a centrally located cylindrical section measuring 6 mm in diameter and 40 mm in length. A unit cell of size 3 mm was prepared for the selected structure based on the compression and static bending test results. An Instron 8874 mechanical testing system was used in this study. The test conditions were as follows: the cyclic wave shape was sinusoidal, the load ratio was 0.1, the cyclic frequency was 10 Hz, and the number of cycles was the cumulative number of tests until the specimens were destroyed. When the number of cycles was 106 or more, no breakage was defined. A preliminary tensile test was performed on the three samples, and the reference load value was determined. Ten specimens were prepared for evaluation. From the results, an S–N curve was generated; the vertical axis represented the maximum stress (S), and the horizontal axis represented the number of cycles (N).

2.6. Statistical Analysis

All values are reported as mean ± standard deviation. Statistical analyses were performed for each experiment. One-way analysis of variance (ANOVA) was used to compare the mean value among groups. If the ANOVA was significant, Tukey’s multiple comparison analysis was used as a post hoc test.

3. Results

3.1. Selection of Lattice Structures by a Numerical Material Test

Table 1 lists the results of the numerical material tests for the 28 lattice structures. Figure 1 shows the positive correlation between the equivalent physical properties and relative density in each lattice structure. The structures that satisfied the set Young’s modulus condition (10–30 GPa) were body diagonals with nodes and body diagonals with rounded nodes, which were structures of the same type.
Diamond- and honeycomb-shaped lattice structures are rigid, and the stiffness depends on the length of the strut, cross-sectional area, and thickness of the shell. The relationship between the overall density and Young’s modulus was confirmed, and it was demonstrated that the lower the porosity, the higher the rigidity. The shape of the basic cells (triangular or square) indicates vulnerability in certain directions. Regarding the directionality of the lattice arrangement, a constant Young’s modulus was observed in all directions in the isotropic lattice arrangement; however, stiffness was observed in a specific direction in the anisotropic lattice arrangement.
To avoid bias in the structural strength, three lattices of body diagonals with nodes (BDN), G-structure 10 (G10), and dode—medium (DM) with different structural characteristics were selected as the specimen preparation conditions for the compression and static bending tests. Each lattice density was 0.50, 0.30, and 0.13 g/cm3, respectively, and their relative densities were 141.94, 84.54, and 35.63 g/cm3, respectively. In the bending fatigue test, BDN was selected as the specimen preparation condition. Figure 2 shows an image of each lattice structure. BDN is a body-centered cubic lattice with nodes located at each vertex and the center of the cube; because there is a fulcrum at the center of the diagonal, the structure constructed from its cells can be confirmed to have a constant isotropic Young’s modulus [29]. G10 is a two-dimensional honeycomb-like lattice in which three graphene structures are bonded to one cell, forming a hexagonal network [30]. DM is a lattice structure based on a dodecahedron, and although the shape of the basic cells makes it vulnerable in certain directions, it does have a certain degree of rigidity [31].

3.2. Compression Test

Figure 3 shows the results of the compression test. The average 0.2% offset load values designed for the unit cell size of 3 mm for BDN, G10, and DM were 194.8 ± 6.4, 104 ± 1.3, and 48.7 ± 1.3 MPa, respectively. Those of 4 mm of BDN, G10, and DM were 159.0 ± 5.9, 72.2 ± 8.5, and 27.7 ± 2.4 MPa, respectively. Those of 5 mm of BDN, G10, and DM were 115.2 ± 1.1, 88.8 ± 3.2, and 16.1 ± 0.6 MPa, respectively. The cell size of 3 mm had a significantly higher offset value of 0.2% than the cell sizes of 4 and 5 mm. No significant difference was observed between the cell sizes of 4 mm and 5 mm in G10 (Figure 3a). The BDN showed significant stiffness for each cell size (Figure 3b). Figure 4 shows the stress–strain curves. In BDN and G10, the stress decreased rapidly after exceeding the maximum stress. However, the stress in the DM gradually decreased after breaking.

3.3. Static Bending Test

Figure 5 shows the results of the static bending test. The average 0.2% offset load values designed for the unit cell size of 3 mm for BDN, G10, and DM were 498.0 ± 33.7, 212.0 ± 12.9, and 119.5 ± 13.3 N, respectively. Those of 4 mm of BDN, G10, and DM were 366.0 ± 42.4, 44.6 ± 4.1, and 96.6 ± 13.4 N, respectively. Those of 5 mm BDN, G10, and DM were 321.0 ± 11.1, 66.3 ± 6.1, and 38.6 ± 6.3 N, respectively. Among the three lattice structures, the cell size of 3 mm had a significantly higher offset value of 0.2% than the cell sizes of 4 and 5 mm. No significant difference was observed between the cell sizes of 4 mm and 5 mm in G10 (Figure 5a). The BDN showed significant stiffness for each cell size (Figure 5b). Figure 6 shows the load–displacement curves. Collapse occurred rapidly after the maximum stress in the BDN, but not in the others.

3.4. Fatigue Test

The reference load value was determined as 175.6 N based on the preliminary tensile test. Figure 7 shows the S–N curves. At maximum stresses of 85, 65, 50, 35, 30, 20, and 15 MPa, breakage was observed after 1125, 3288, 6252, 30,905, 52,969, 291,183, and 808,463 cycles, respectively. No breakage was observed at 12 MPa after 106 cycles.

4. Discussion

In recent years, the application of biomaterials made by metal additive manufacturing has been considered in reconstructive surgery in various areas. Metal additive manufacturing is useful for improving the morphology and function of patient-specific defects, and the internal porosity provides stronger integration in the body and long-term durability [32]. The implant with the lattice structure has a more uniform pressure distribution at the interface between the implant and the bone than the non-lattice structure [33]. It has also been reported that adding a lattice structure to the root of dental implants improves initial stability [34]. Because the porosity of the lattice structure is important, a method has been reported to ensure that fabrication errors do not prevent the formation of porosity in lattice structures produced by laser additive manufacturing [35]. In clinical applications of artificial bones with a lattice structure, a clinical study on a prosthesis for a pelvic defect reported that it was useful and that no complications occurred [36]. In the oral and maxillofacial field, the application of artificial metal bone with a lattice structure customized to a patient’s alveolar defect has been reported [37]; however, there has been no evaluation of its mechanical strength. The artificial bone with a lattice structure in this present study not only reconstructed the defect but also demonstrated durability against mechanical stress around the mandible.
Various methods for mandibular reconstruction during oral surgery have been reported [38,39,40,41]. Reconstruction using titanium plates is simple, but it does not reconstruct the bone tissue and may lead to fatigue fracture [5]. Bone reconstruction using the ilium, fibula, and scapula involves the reconstruction of bone tissue; however, reconstruction of the ideal mandibular morphology is difficult. Mandibular reconstruction using a titanium mesh and iliac particulate cancellous bone and marrow can reconstruct the ideal mandibular morphology; however, there is a risk of titanium mesh fracture [42]. In this study, a titanium biomaterial with a lattice structure was designed for mandibular reconstruction that ideally reconstructs the mandibular shape, minimizes the use of grafted bone, and provides the appropriate strength. Furthermore, as the filling rate and pore size of the structure of cancellous bone is determined by the degree of internal stress and the anisotropy of the structure is determined by the direction of the internal stress, a lattice structure was proposed as an ideal structure that can prevent excessive stress concentration by continuously connecting structures with different local anisotropies while also ensuring the overall strength.
Material evaluation is based directly on the results of material testing; however, conducting a strength analysis of all lattice structure test specimens is expected to be extremely costly and time-consuming. Therefore, an evaluation was performed using finite analysis software. In the numerical material test, the apparent equivalent physical property values and relative density of the structure were compared, and a positive correlation was found between the equivalent physical property values and the Young’s modulus. The results indicated that the higher the relative density, the higher the Young’s modulus. Furthermore, because the type of lattice structure has a significant effect on mechanical properties, it may be possible to find an optimal structure by adjusting the topology, components, porosity, cell shape, and orientation of the lattice structure. In this study, because only two structures of the same type had a set Young’s modulus, one of them, BDN, was selected, and the other two, G10 and DM, which had different conditions, were selected to avoid bias in the structural strength.
The compression and static bending tests suggested that the smaller and more uniform the cells constituting the lattice, the higher the compressive strength, and that the compressive strength increased with the density of the structure. In BND and G10, the stress decreased rapidly after exceeding the maximum stress. They initially exhibited elastic deformation; however, when a certain stress was exceeded, plastic deformation might have occurred. However, stress did not decrease rapidly even after collapse occurred in the DM, probably owing to small breaks occurring intermittently rather than large breaks occurring until collapse occurred. The elastic modulus of each material exhibited different values depending on its structural characteristics. This strength was lower than that obtained in the numerical material test. This might be due to the weak bonding of the unit cells during specimen preparation [43].
The fatigue test for the BDN indicated a durability of 12 MPa. This value is approximately 4000 times the bite force of the molars in adults [44]. This suggests that a basic structure with a lattice structure of BDN and a cell size of 3.0 mm is effective for developing an artificial titanium mandible that can reconstruct the mandible shape of each patient using computer-aided design and manufacturing technology and the electron-beam additive manufacturing method that have been developed thus far, while also being strong enough to withstand biting forces.
This study investigated the lattice structure in the preparation of a metallic artificial mandible. In the future, it will be necessary to evaluate the reactivity of the body and mechanical strength of mandibular morphology. Artificial bones based on highly rigid and lightweight lattice structures are expected to be useful for mandibular reconstruction. However, as the reaction in the in vivo environment and long-term durability have not been confirmed, further investigation is required.

5. Conclusions

A basic lattice structure was investigated to develop a mandibular reconstruction method that would ideally reconstruct the mandibular shape, minimize the use of grafted bone, and achieve appropriate strength. When manufacturing titanium biomaterials with a lattice structure, BDN, which exhibits constant strength in an isotropic manner, has the optimal strength, and a structure with a cell size of 3.0 mm is optimal. Therefore, an artificial metal mandible with a lattice structure that meets these conditions could be a candidate for mandibular reconstruction. This method is expected to reduce the invasiveness to the patient by minimizing the amount of autologous bone harvested, and to be able to withstand biting forces and improve aesthetics. However, surface reactions in simulated body fluid environments and evaluation in in vivo environments have not yet been confirmed, so further research is needed before any clinical application.

Author Contributions

Conceptualization, S.K. (Shinsuke Kawamata), T.K., E.Y., I.H. and H.Y.; methodology, S.K. (Shinsuke Kawamata), I.H., T.M. and S.K. (Shingo Kurosu); validation, S.K. (Shinsuke Kawamata), T.K., T.M. and S.K. (Shingo Kurosu); formal analysis, S.K. (Shinsuke Kawamata); investigation, S.K. (Shingo Kurosu) and T.M.; data curation, S.K. (Shinsuke Kawamata), S.K. (Shingo Kurosu), and T.M.; writing—original draft preparation, S.K. (Shinsuke Kawamata) and T.K.; writing—review and editing, T.K.; visualization, S.K. (Shinsuke Kawamata) and T.K.; supervision, H.Y.; project administration, H.Y. All authors have read and agreed to the published version of the manuscript.

Funding

This study was supported in part by a Grant-in-Aid (23K09360) from the Ministry of Education, Science, Sports, and Culture of Japan, and by the Japan Keirin Autorace Foundation (2023M-250).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The raw data required to reproduce these results cannot be shared at this time, as the data also form part of an ongoing study.

Acknowledgments

The authors thank Shinji Takemoto for his invaluable advice on material science.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Sjöström, M.; Danielsson, D.; Munck-Wikland, E.; Nyberg, J.; Sandström, K.; Thor, A.; Johansson, H.; Ceghafi, P.; Udd, S.D.; Emanuelsson, J.; et al. Mandibular resection in patients with head and neck cancer: Acute and long-term complications after reconstruction. Acta Oto-Laryngol. 2022, 142, 78–83. [Google Scholar] [CrossRef] [PubMed]
  2. Kasper, R.; Scheurer, M.; Pietzka, S.; Sakkas, A.; Schramm, A.; Wilde, F.; Ebeling, M. MRONJ of the Mandible—From Decortication to a Complex Jaw Reconstruction Using a CAD/CAM-Guided Bilateral Scapula Flap. Medicina 2023, 59, 535. [Google Scholar] [CrossRef] [PubMed]
  3. Wongwaithongdee, U.; Inglam, S.; Chantarapanich, N. Biomechanical evaluation of two internal fixation systems for the treatment of mandibular symphyseal fracture. Proc. Inst. Mech. Eng. Part H J. Eng. Med. 2023, 237, 597–606. [Google Scholar] [CrossRef] [PubMed]
  4. Tarsitano, A.; Ceccariglia, F.; Bevini, M.; Breschi, L.; Felice, P.; Marchetti, C. Prosthetically guided mandibular reconstruction using a fibula free flap: Three-dimensional Bologna plate, an alternative to the double-barrel technique. Int. J. Oral Maxillofac. Surg. 2023, 52, 436–441. [Google Scholar] [CrossRef] [PubMed]
  5. Almansoori, A.A.; Choung, H.W.; Kim, B.; Park, J.Y.; Kim, S.M.; Lee, J.H. Fracture of Standard Titanium Mandibular Reconstruction Plates and Preliminary Study of Three-Dimensional Printed Reconstruction Plates. J. Oral Maxillofac. Surg. Off. J. Am. Assoc. Oral Maxillofac. Surg. 2020, 78, 153–166. [Google Scholar] [CrossRef] [PubMed]
  6. Zhao, Z.; Shen, S.; Li, M.; Shen, G.; Ding, G.; Yu, H. Three-dimensional printed titanium mesh combined with iliac cancellous bone in the reconstruction of mandibular defects secondary to ameloblastoma resection. BMC Oral Health 2023, 23, 681. [Google Scholar] [CrossRef] [PubMed]
  7. Wang, Q.S.; Li, S.J.; Hou, W.T.; Wang, S.G.; Hao, Y.L.; Yang, R.; Misra, R.D.K. Mechanistic understanding of compression-compression fatigue behavior of functionally graded Ti-6Al-4V mesh structure fabricated by electron beam melting. J. Mech. Behav. Biomed. Materials 2020, 103, 103590. [Google Scholar] [CrossRef] [PubMed]
  8. Wang, Z.; Ummethala, R.; Singh, N.; Tang, S.; Suryanarayana, C.; Eckert, J.; Prashanth, K.G. Selective Laser Melting of Aluminum and Its Alloys. Material 2020, 13, 4564. [Google Scholar] [CrossRef] [PubMed]
  9. Zhang, L.-C.; Liu, Y.; Li, S.; Hao, Y. Additive Manufacturing of Titanium Alloys by Electron Beam Melting: A Review. Adv. Eng. Mater. 2018, 20, 1700842. [Google Scholar] [CrossRef]
  10. Hoshi, I.; Kawai, T.; Kurosu, S.; Minamino, T.; Onodera, K.; Miyamoto, I.; Yamada, H. Custom-Made Titanium Mesh Tray for Mandibular Reconstruction Using an Electron Beam Melting System. Material 2021, 14, 6556. [Google Scholar] [CrossRef] [PubMed]
  11. Wu, N.; Li, S.; Liu, Y.; Zhang, A.; Chen, B.; Han, Q.; Wang, J. Novel exploration of 3D printed personalized total elbow arthroplasty to solve the severe bone defect after internal fixation failure of comminuted distal humerus fracture: A case report. Medicine 2020, 99, e21481. [Google Scholar] [CrossRef] [PubMed]
  12. Meng, M.; Wang, J.; Huang, H.; Liu, X.; Zhang, J.; Li, Z. 3D printing metal implants in orthopedic surgery: Methods, applications and future prospects. J. Orthop. Transl. 2023, 42, 94–112. [Google Scholar] [CrossRef] [PubMed]
  13. Yang, L. 9-Safety of nanotechnology-enhanced orthopedic materials. In Nanotechnology-Enhanced Orthopedic Materials; Yang, L., Ed.; Woodhead Publishing: Oxford, UK, 2015; pp. 181–195. [Google Scholar]
  14. Maconachie, T.; Leary, M.; Tran, P.; Harris, J.; Liu, Q.; Lu, G.; Ruan, D.; Faruque, O.; Brandt, M. The effect of topology on the quasi-static and dynamic behaviour of SLM AlSi10Mg lattice structures. Int. J. Adv. Manuf. Technol. 2022, 118, 4085–4104. [Google Scholar] [CrossRef]
  15. Kim, T.; Zhao, C.Y.; Lu, T.J.; Hodson, H.P. Convective heat dissipation with lattice-frame materials. Mech. Mater. 2004, 36, 767–780. [Google Scholar] [CrossRef]
  16. Distefano, F.; Pasta, S.; Epasto, G. Titanium Lattice Structures Produced via Additive Manufacturing for a Bone Scaffold: A Review. J. Funct. Biomater. 2023, 14, 125. [Google Scholar] [CrossRef] [PubMed]
  17. Pałka, K.; Pokrowiecki, R. Porous Titanium Implants: A Review. Adv. Eng. Mater. 2018, 20, 1700648. [Google Scholar] [CrossRef]
  18. Sing, S.L.; Yeong, W.Y.; Wiria, F.E. Selective laser melting of titanium alloy with 50 wt% tantalum: Microstructure and mechanical properties. J. Alloys Compd. 2016, 660, 461–470. [Google Scholar] [CrossRef]
  19. Taniguchi, N.; Fujibayashi, S.; Takemoto, M.; Sasaki, K.; Otsuki, B.; Nakamura, T.; Matsushita, T.; Kokubo, T.; Matsuda, S. Effect of pore size on bone ingrowth into porous titanium implants fabricated by additive manufacturing: An in vivo experiment. Mater. Sci. Eng. C Mater. Biol. Appl. 2016, 59, 690–701. [Google Scholar] [CrossRef] [PubMed]
  20. Ushijima, K.; Akiyoshi, T.; Chen, D.-H.; Nakahara, T.; Cantwell, W.J. Estimation of Bending Behaviour for Beams Composed of Three-Dimensional Micro-Lattice Cells (Part 1 Based on Numerical Analysis). Trans. Jpn. Soc. Mech. Eng. Part A 2013, 79, 620–632. [Google Scholar] [CrossRef]
  21. Ushijima, K.; Chen, D.-H.; Cantwell, W.J.; Seo, M. Shear Deformation Response for Three-Dimensional Lattice Structures (1st Report, effects of geometry of overall lattice structure). Trans. Jpn. Soc. Mech. Eng. Part A 2010, 76, 1557–1564. [Google Scholar] [CrossRef]
  22. Ushijima, K.; Chen, D.-H.; Cantwell, W.J.; Seo, M. Shear Deformation Response for Three-Dimensional Lattice Structures (2nd Report, Effects of Unit Cell Geometry in a Lattice Structure). Trans. Jpn. Soc. Mech. Eng. Part A 2011, 77, 1417–1432. [Google Scholar] [CrossRef]
  23. Hattori, Y.; Sato, C.; Watanabe, M. Bite force distribution on dental arch during clenching. J. Jpn. Soc. Stomatognathic Funct. 1996, 2, 111–117. [Google Scholar] [CrossRef]
  24. Satoh, C. A Study of Bite Force Distribution on the Dental Arch in Normal Subjects. J. Jpn. Prosthodont. Soc. 1997, 41, 634–644. [Google Scholar] [CrossRef]
  25. Dahlberg, B. The masticatory habits; an analysis of the number of chews when consuming food. J. Dent. Res. 1946, 25, 67–72. [Google Scholar] [CrossRef] [PubMed]
  26. JIS T 0309; Test Method for Fatigue Properties of Metallic Biomaterials. Japanese Industrial Standards Committee: Tokyo, Japan, 2009.
  27. JIS T 0312; Testing Methods for Bending Properties of Metallic Osteosynthesis. Japanese Standards Committee: Tokyo, Japan, 2009.
  28. JIS T 0313; Testing Methods for Compression Bending Properties of Metallic Osteosynthesis Devices. Japanese Standards Committee: Tokyo, Japan, 2009.
  29. Ma, X.; Zhang, N.; Chang, Y.; Tian, X. Analytical model of mechanical properties for a hierarchical lattice structure based on hierarchical body-centered cubic unit cell. Thin-Walled Struct. 2023, 193, 111217. [Google Scholar] [CrossRef]
  30. Tian, W.; Li, W.; Yu, W.; Liu, X. A Review on Lattice Defects in Graphene: Types, Generation, Effects and Regulation. Micromachines 2017, 8, 163. [Google Scholar] [CrossRef]
  31. Xiao, L.; Song, W.; Wang, C.; Tang, H.; Fan, Q.; Liu, N.; Wang, J. Mechanical properties of open-cell rhombic dodecahedron titanium alloy lattice structure manufactured using electron beam melting under dynamic loading. Int. J. Impact Eng. 2017, 100, 75–89. [Google Scholar] [CrossRef]
  32. Davoodi, E.; Montazerian, H.; Mirhakimi, A.S.; Zhianmanesh, M.; Ibhadode, O.; Shahabad, S.I.; Esmaeilizadeh, R.; Sarikhani, E.; Toorandaz, S.; Sarabi, S.A.; et al. Additively manufactured metallic biomaterials. Bioact. Mater. 2022, 15, 214–249. [Google Scholar] [CrossRef] [PubMed]
  33. Distefano, F.; Epasto, G.; Guglielmino, E.; Amata, A.; Mineo, R. Subsidence of a partially porous titanium lumbar cage produced by electron beam melting technology. J. Biomed. Mater. Res. Part B Appl. Biomater. 2023, 111, 590–598. [Google Scholar] [CrossRef]
  34. Lee, J.; Li, L.; Song, H.Y.; Son, M.J.; Lee, Y.M.; Koo, K.T. Impact of lattice versus solid structure of 3D-printed multiroot dental implants using Ti-6Al-4V: A preclinical pilot study. J. Periodontal Implant. Sci. 2022, 52, 338–350. [Google Scholar] [CrossRef] [PubMed]
  35. Park, J.W.; Park, H.; Kim, J.H.; Kim, H.M.; Yoo, C.H.; Kang, H.G. Fabrication of a lattice structure with periodic open pores through three-dimensional printing for bone ingrowth. Sci. Rep. 2022, 12, 17223. [Google Scholar] [CrossRef] [PubMed]
  36. Li, Z.; Luo, Y.; Lu, M.; Wang, Y.; Gong, T.; He, X.; Hu, X.; Long, J.; Zhou, Y.; Min, L.; et al. Biomimetic design and clinical application of Ti-6Al-4V lattice hemipelvis prosthesis for pelvic reconstruction. J. Orthop. Surg. Res. 2024, 19, 210. [Google Scholar] [CrossRef] [PubMed]
  37. Seiler, M.; Kämmerer, P.W.; Peetz, M.; Hartmann, A. Customized lattice structure in reconstruction of three-dimensional alveolar defects. Int. J. Comput. Dent. 2018, 21, 261–267. [Google Scholar] [PubMed]
  38. Yagihara, K.; Okabe, S.; Ishii, J.; Amagasa, T.; Yamashiro, M.; Yamaguchi, S.; Yokoya, S.; Yamazaki, T.; Kinoshita, Y. Mandibular reconstruction using a poly(L-lactide) mesh combined with autogenous particulate cancellous bone and marrow: A prospective clinical study. Int. J. Oral Maxillofac. Surg. 2013, 42, 962–969. [Google Scholar] [CrossRef] [PubMed]
  39. Yang, W.F.; Choi, W.S.; Zhu, W.Y.; Su, Y.X. “One-piece” patient-specific reconstruction plate for double-barrel fibula-based mandibular reconstruction. Int. J. Oral Maxillofac. Surg. 2020, 49, 1016–1019. [Google Scholar] [CrossRef]
  40. Saijo, H.; Kanno, Y.; Mori, Y.; Suzuki, S.; Ohkubo, K.; Chikazu, D.; Yonehara, Y.; Chung, U.I.; Takato, T. A novel method for designing and fabricating custom-made artificial bones. Int. J. Oral Maxillofac. Surg. 2011, 40, 955–960. [Google Scholar] [CrossRef] [PubMed]
  41. Matsuo, A.; Chiba, H.; Takahashi, H.; Toyoda, J.; Abukawa, H. Clinical application of a custom-made bioresorbable raw particulate hydroxyapatite/poly-L-lactide mesh tray for mandibular reconstruction. Odontology 2010, 98, 85–88. [Google Scholar] [CrossRef] [PubMed]
  42. Aytaç, S.; Ozbek, S.; Kahveci, R.; Ozgenel, Y.; Akin, S.; Ozcan, M. Titanium mesh fracture in mandibular reconstruction. J. Craniofac. Surg. 2005, 16, 1120–1122. [Google Scholar] [CrossRef] [PubMed]
  43. Smith, M.; Guan, Z.; Cantwell, W.J. Finite element modelling of the compressive response of lattice structures manufactured using the selective laser melting technique. Int. J. Mech. Sci. 2013, 67, 28–41. [Google Scholar] [CrossRef]
  44. Kobayashi, R. Improvements in occlusion after orthognathic surgery. Jpn. J. Oral Maxillofac. Surg. 1990, 36, 2473–2490. [Google Scholar] [CrossRef]
Materials 17 03557 g001
Figure 1. Equivalent physical properties and the relative density of each lattice structure. Structures that met the set criteria are body diagonals with nodes and body diagonals with rounded nodes, which are structures of the same type.
Figure 1. Equivalent physical properties and the relative density of each lattice structure. Structures that met the set criteria are body diagonals with nodes and body diagonals with rounded nodes, which are structures of the same type.
Materials 17 03557 g001
Materials 17 03557 g002
Figure 2. Images of lattice structures selected from the numerical material test. (a) BDN. A body-centered cubic lattice with nodes located at each vertex and the center of the cube. (b) G10. A two-dimensional honeycomb-like lattice, in which three graphene structures are bonded to one cell, forming a hexagonal network. (c) DM. Lattice structures based on dodecahedra.
Figure 2. Images of lattice structures selected from the numerical material test. (a) BDN. A body-centered cubic lattice with nodes located at each vertex and the center of the cube. (b) G10. A two-dimensional honeycomb-like lattice, in which three graphene structures are bonded to one cell, forming a hexagonal network. (c) DM. Lattice structures based on dodecahedra.
Materials 17 03557 g002
Materials 17 03557 g003
Figure 3. Result of the compression test. (a) Comparison of cell sizes for each lattice structure. For each of the three lattice structures, the cell size of 3 mm exhibited more stiffness than the cell sizes of 4 and 5 mm. (b) Comparison of the lattice structures for each cell size. BDN shows significant stiffness at each cell size compared to the others. Tukey’s multiple comparison analysis. * p < 0.05.
Figure 3. Result of the compression test. (a) Comparison of cell sizes for each lattice structure. For each of the three lattice structures, the cell size of 3 mm exhibited more stiffness than the cell sizes of 4 and 5 mm. (b) Comparison of the lattice structures for each cell size. BDN shows significant stiffness at each cell size compared to the others. Tukey’s multiple comparison analysis. * p < 0.05.
Materials 17 03557 g003
Materials 17 03557 g004
Figure 4. Stress–strain curve of the compression test. In BDN and G10, stress decreases rapidly after exceeding the maximum stress. In DM, the stress decreases slowly after the break. The straight line indicates BDN, the dashed line indicates G10, and the dotted line indicates DM. The number indicates the cell size.
Figure 4. Stress–strain curve of the compression test. In BDN and G10, stress decreases rapidly after exceeding the maximum stress. In DM, the stress decreases slowly after the break. The straight line indicates BDN, the dashed line indicates G10, and the dotted line indicates DM. The number indicates the cell size.
Materials 17 03557 g004
Materials 17 03557 g005
Figure 5. Results of the static bending test. (a) Comparison of cell sizes for each lattice structure. For each of the three lattice structures, the cell size of 3 mm exhibited more stiffness than the cell sizes of 4 and 5 mm. (b) Comparison of lattice structures for each cell size. BDN shows significant stiffness at each cell size compared to others. Tukey’s multiple comparison analysis. * p < 0.05.
Figure 5. Results of the static bending test. (a) Comparison of cell sizes for each lattice structure. For each of the three lattice structures, the cell size of 3 mm exhibited more stiffness than the cell sizes of 4 and 5 mm. (b) Comparison of lattice structures for each cell size. BDN shows significant stiffness at each cell size compared to others. Tukey’s multiple comparison analysis. * p < 0.05.
Materials 17 03557 g005
Materials 17 03557 g006
Figure 6. Load–displacement curve. Collapse occurs rapidly after the maximum stress in BDN. The straight line indicates BDN, the dashed line indicates G10, and the dotted line indicates DM. The numbers indicate the cell size.
Figure 6. Load–displacement curve. Collapse occurs rapidly after the maximum stress in BDN. The straight line indicates BDN, the dashed line indicates G10, and the dotted line indicates DM. The numbers indicate the cell size.
Materials 17 03557 g006
Materials 17 03557 g007
Figure 7. S–N curve from the fatigue test of BDN specimens. No breakage is observed at 12 MPa until 106 cycles. Arrows indicate no breakage.
Figure 7. S–N curve from the fatigue test of BDN specimens. No breakage is observed at 12 MPa until 106 cycles. Arrows indicate no breakage.
Materials 17 03557 g007
Table 1. Numerical material test of 28 lattice structures.
Table 1. Numerical material test of 28 lattice structures.
StructuresEquivalent Physical Properties (MPa)Relative Density
X Axis
Direction		Y Axis
Direction		Z Axis
Direction		Average
Body diagonals with rounded nodes15,99515,99615,97115,98745.40%
Body diagonals with nodes16,86416,69416,62216,72750.20%
Cross510951095109510910.40%
Cross-113901390139013903.20%
Cross-215991598159815984.20%
Cross-316351635163516354.60%
Cross-X34823,333434803919.40%
Cross-X reinforced36699452602.70%
Diamond 20 percent relative density279327932793279320.00%
Diamond 30 percent relative density663566356634663529.60%
Dode—medium63063063063012.60%
Dode—thick302630273027302724.60%
Dode—thin474747473.90%
G-structure221493424215025748.40%
G-structure355321255243912.00%
G-structure4420642064206420610.60%
G-structure6603160316031603111.90%
G-structure780524438052551514.80%
G-structure825191324252021217.50%
G-structure9392040034901427522.40%
G-structure106619778710,681836229.90%
Octet truss relative density 30 percent812081198100811329.30%
Rhombi_Octa-Dense583758375837583715.40%
Rhombi_Octa-Light267226722672267210.10%
Rhombic dodecahedron relative density 20 percent196419641975196819.40%
Rhombic dodecahedron relative density 30 percent567356735675567429.80%
Trunc Octa-Dense651364526348643824.70%
Trunc Octa-Light359034813458350920.40%
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Kawamata, S.; Kawai, T.; Yasuge, E.; Hoshi, I.; Minamino, T.; Kurosu, S.; Yamada, H. Investigation of the Mechanical Strength of Artificial Metallic Mandibles with Lattice Structure for Mandibular Reconstruction. Materials 2024, 17, 3557. https://doi.org/10.3390/ma17143557

AMA Style

Kawamata S, Kawai T, Yasuge E, Hoshi I, Minamino T, Kurosu S, Yamada H. Investigation of the Mechanical Strength of Artificial Metallic Mandibles with Lattice Structure for Mandibular Reconstruction. Materials. 2024; 17(14):3557. https://doi.org/10.3390/ma17143557

Chicago/Turabian Style

Kawamata, Shinsuke, Tadashi Kawai, Erika Yasuge, Isao Hoshi, Tadaharu Minamino, Shingo Kurosu, and Hiroyuki Yamada. 2024. "Investigation of the Mechanical Strength of Artificial Metallic Mandibles with Lattice Structure for Mandibular Reconstruction" Materials 17, no. 14: 3557. https://doi.org/10.3390/ma17143557

APA Style

Kawamata, S., Kawai, T., Yasuge, E., Hoshi, I., Minamino, T., Kurosu, S., & Yamada, H. (2024). Investigation of the Mechanical Strength of Artificial Metallic Mandibles with Lattice Structure for Mandibular Reconstruction. Materials, 17(14), 3557. https://doi.org/10.3390/ma17143557

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop