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Matsuura T, Komatsu K, Cheng J, Park G, Ogawa T. Beyond microroughness: novel approaches to navigate osteoblast activity on implant surfaces. Int J Implant Dent 2024; 10:35. [PMID: 38967690 PMCID: PMC11226592 DOI: 10.1186/s40729-024-00554-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 06/15/2024] [Indexed: 07/06/2024] Open
Abstract
Considering the biological activity of osteoblasts is crucial when devising new approaches to enhance the osseointegration of implant surfaces, as their behavior profoundly influences clinical outcomes. An established inverse correlation exists between osteoblast proliferation and their functional differentiation, which constrains the rapid generation of a significant amount of bone. Examining the surface morphology of implants reveals that roughened titanium surfaces facilitate rapid but thin bone formation, whereas smooth, machined surfaces promote greater volumes of bone formation albeit at a slower pace. Consequently, osteoblasts differentiate faster on roughened surfaces but at the expense of proliferation speed. Moreover, the attachment and initial spreading behavior of osteoblasts are notably compromised on microrough surfaces. This review delves into our current understanding and recent advances in nanonodular texturing, meso-scale texturing, and UV photofunctionalization as potential strategies to address the "biological dilemma" of osteoblast kinetics, aiming to improve the quality and quantity of osseointegration. We discuss how these topographical and physicochemical strategies effectively mitigate and even overcome the dichotomy of osteoblast behavior and the biological challenges posed by microrough surfaces. Indeed, surfaces modified with these strategies exhibit enhanced recruitment, attachment, spread, and proliferation of osteoblasts compared to smooth surfaces, while maintaining or amplifying the inherent advantage of cell differentiation. These technology platforms suggest promising avenues for the development of future implants.
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Affiliation(s)
- Takanori Matsuura
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, 10833 Le Conte Avenue B3-087, Box951668, Los Angeles, CA, 90095-1668, USA
| | - Keiji Komatsu
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, 10833 Le Conte Avenue B3-087, Box951668, Los Angeles, CA, 90095-1668, USA
| | - James Cheng
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, 10833 Le Conte Avenue B3-087, Box951668, Los Angeles, CA, 90095-1668, USA
- Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, USA
| | - Gunwoo Park
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, 10833 Le Conte Avenue B3-087, Box951668, Los Angeles, CA, 90095-1668, USA
| | - Takahiro Ogawa
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, 10833 Le Conte Avenue B3-087, Box951668, Los Angeles, CA, 90095-1668, USA.
- Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, USA.
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Komatsu K, Matsuura T, Cheng J, Kido D, Park W, Ogawa T. Nanofeatured surfaces in dental implants: contemporary insights and impending challenges. Int J Implant Dent 2024; 10:34. [PMID: 38963524 PMCID: PMC11224214 DOI: 10.1186/s40729-024-00550-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Accepted: 05/27/2024] [Indexed: 07/05/2024] Open
Abstract
Dental implant therapy, established as standard-of-care nearly three decades ago with the advent of microrough titanium surfaces, revolutionized clinical outcomes through enhanced osseointegration. However, despite this pivotal advancement, challenges persist, including prolonged healing times, restricted clinical indications, plateauing success rates, and a notable incidence of peri-implantitis. This review explores the biological merits and constraints of microrough surfaces and evaluates the current landscape of nanofeatured dental implant surfaces, aiming to illuminate strategies for addressing existing impediments in implant therapy. Currently available nanofeatured dental implants incorporated nano-structures onto their predecessor microrough surfaces. While nanofeature integration into microrough surfaces demonstrates potential for enhancing early-stage osseointegration, it falls short of surpassing its predecessors in terms of osseointegration capacity. This discrepancy may be attributed, in part, to the inherent "dichotomy kinetics" of osteoblasts, wherein increased surface roughness by nanofeatures enhances osteoblast differentiation but concomitantly impedes cell attachment and proliferation. We also showcase a controllable, hybrid micro-nano titanium model surface and contrast it with commercially-available nanofeatured surfaces. Unlike the commercial nanofeatured surfaces, the controllable micro-nano hybrid surface exhibits superior potential for enhancing both cell differentiation and proliferation. Hence, present nanofeatured dental implants represent an evolutionary step from conventional microrough implants, yet they presently lack transformative capacity to surmount existing limitations. Further research and development endeavors are imperative to devise optimized surfaces rooted in fundamental science, thereby propelling technological progress in the field.
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Affiliation(s)
- Keiji Komatsu
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, USA
| | - Takanori Matsuura
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, USA
| | - James Cheng
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, USA
- Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, USA
- Section of Periodontics, UCLA School of Dentistry, Los Angeles, USA
| | - Daisuke Kido
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, USA
| | - Wonhee Park
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, USA
- Department of Dentistry, College of Medicine, Hanyang University, Seoul, Korea
| | - Takahiro Ogawa
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, USA.
- Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, USA.
- Weintraub Center for Reconstructive Biotechnology, Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, 10833 Le Conte Avenue B3-087, Box951668, Los Angeles, CA, 90095-1668, USA.
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Park G, Matsuura T, Komatsu K, Ogawa T. Optimizing implant osseointegration, soft tissue responses, and bacterial inhibition: A comprehensive narrative review on the multifaceted approach of the UV photofunctionalization of titanium. J Prosthodont Res 2024:JPR_D_24_00086. [PMID: 38853001 DOI: 10.2186/jpr.jpr_d_24_00086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Titanium implants have revolutionized restorative and reconstructive therapy, yet achieving optimal osseointegration and ensuring long-term implant success remain persistent challenges. In this review, we explore a cutting-edge approach to enhancing implant properties: ultraviolet (UV) photofunctionalization. By harnessing UV energy, photofunctionalization rejuvenates aging implants, leveraging and often surpassing the intrinsic potential of titanium materials. The primary aim of this narrative review is to offer an updated perspective on the advancements made in the field, providing a comprehensive overview of recent findings and exploring the relationship between UV-induced physicochemical alterations and cellular responses. There is now compelling evidence of significant transformations in titanium surface chemistry induced by photofunctionalization, transitioning from hydrocarbon-rich to carbon pellicle-free surfaces, generating superhydrophilic surfaces, and modulating the electrostatic properties. These changes are closely associated with improved cellular attachment, spreading, proliferation, differentiation, and, ultimately, osseointegration. Additionally, we discuss clinical studies demonstrating the efficacy of UV photofunctionalization in accelerating and enhancing the osseointegration of dental implants. Furthermore, we delve into recent advancements, including the development of one-minute vacuum UV (VUV) photofunctionalization, which addresses the limitations of conventional UV methods as well as the newly discovered functions of photofunctionalization in modulating soft tissue and bacterial interfaces. By elucidating the intricate relationship between surface science and biology, this body of research lays the groundwork for innovative strategies aimed at enhancing the clinical performance of titanium implants, marking a new era in implantology.
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Affiliation(s)
- Gunwoo Park
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, USA
| | - Takanori Matsuura
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, USA
| | - Keiji Komatsu
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, USA
| | - Takahiro Ogawa
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, USA
- Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, USA
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Corsaro C, Orlando G, Costa G, Latino M, Barreca F, Mezzasalma AM, Neri F, Fazio E. Wetting Behavior Driven by Surface Morphology Changes Induced by Picosecond Laser Texturing. MATERIALS (BASEL, SWITZERLAND) 2024; 17:1719. [PMID: 38673077 PMCID: PMC11051418 DOI: 10.3390/ma17081719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/04/2024] [Accepted: 04/07/2024] [Indexed: 04/28/2024]
Abstract
The laser surface texturing (LST) technique has recently been used to enhance adhesion bond strength in various coating applications and to create structures with controlled hydrophobic or superhydrophobic surfaces. The texturing processing parameters can be adjusted to tune the surface's polarity, thereby controlling the ratio between the polar and dispersed components of the surface free energy and determining its hydrophobic character. The aim of this work is to systematically select appropriate laser and scan head parameters for high-quality surface topography of metal-based materials. A correlation between texturing parameters and wetting properties was made in view of several technological applications, i.e., for the proper growth of conformal layers onto laser-textured metal surfaces. Surface analyses, carried out by scanning electron microscopy and profilometry, reveal the presence of periodic microchannels decorated with laser-induced periodic surface structures (LIPSS) in the direction parallel to the microchannels. The water contact angle varies widely from about 20° to 100°, depending on the treated material (titanium, nickel, etc.). Nowadays, reducing the wettability transition time from hydrophilicity to hydrophobicity, while also changing environmental conditions, remains a challenge. Therefore, the characteristics of environmental dust and its influence on the properties of the picosecond laser-textured surface (e.g., chemical bonding of samples) have been studied while monitoring ambient conditions.
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Affiliation(s)
- Carmelo Corsaro
- Department of Mathematical and Computational Sciences, Physics Science and Earth Science, University of Messina, Viale F. Stagno d’Alcontres 31, I-98166 Messina, Italy; (C.C.); (G.O.); (G.C.); (M.L.); (A.M.M.); (F.N.)
| | - Gabriele Orlando
- Department of Mathematical and Computational Sciences, Physics Science and Earth Science, University of Messina, Viale F. Stagno d’Alcontres 31, I-98166 Messina, Italy; (C.C.); (G.O.); (G.C.); (M.L.); (A.M.M.); (F.N.)
| | - Gabriele Costa
- Department of Mathematical and Computational Sciences, Physics Science and Earth Science, University of Messina, Viale F. Stagno d’Alcontres 31, I-98166 Messina, Italy; (C.C.); (G.O.); (G.C.); (M.L.); (A.M.M.); (F.N.)
| | - Mariangela Latino
- Department of Mathematical and Computational Sciences, Physics Science and Earth Science, University of Messina, Viale F. Stagno d’Alcontres 31, I-98166 Messina, Italy; (C.C.); (G.O.); (G.C.); (M.L.); (A.M.M.); (F.N.)
- CNR-Institute for Chemical and Physical Processes (IPCF), Viale F. Stagno d’Alcontres 37, I-98158 Messina, Italy
| | - Francesco Barreca
- Department of Mathematical and Computational Sciences, Physics Science and Earth Science, University of Messina, Viale F. Stagno d’Alcontres 31, I-98166 Messina, Italy; (C.C.); (G.O.); (G.C.); (M.L.); (A.M.M.); (F.N.)
| | - Angela Maria Mezzasalma
- Department of Mathematical and Computational Sciences, Physics Science and Earth Science, University of Messina, Viale F. Stagno d’Alcontres 31, I-98166 Messina, Italy; (C.C.); (G.O.); (G.C.); (M.L.); (A.M.M.); (F.N.)
| | - Fortunato Neri
- Department of Mathematical and Computational Sciences, Physics Science and Earth Science, University of Messina, Viale F. Stagno d’Alcontres 31, I-98166 Messina, Italy; (C.C.); (G.O.); (G.C.); (M.L.); (A.M.M.); (F.N.)
| | - Enza Fazio
- Department of Mathematical and Computational Sciences, Physics Science and Earth Science, University of Messina, Viale F. Stagno d’Alcontres 31, I-98166 Messina, Italy; (C.C.); (G.O.); (G.C.); (M.L.); (A.M.M.); (F.N.)
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Šugár P, Antala R, Šugárová J, Kováčik J, Pata V. Study on Surface Roughness, Morphology, and Wettability of Laser-Modified Powder Metallurgy-Processed Ti-Graphite Composite Intended for Dental Application. Bioengineering (Basel) 2023; 10:1406. [PMID: 38135997 PMCID: PMC10740645 DOI: 10.3390/bioengineering10121406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 12/05/2023] [Accepted: 12/07/2023] [Indexed: 12/24/2023] Open
Abstract
In this study, the surface laser treatment of a new type of dental biomaterial, a Ti-graphite composite, prepared by low-temperature powder metallurgy, was investigated. Different levels of output laser power and the scanning speed of the fiber nanosecond laser with a wavelength of 1064 nm and argon as a shielding gas were used in this experiment. The surface integrity of the machined surfaces was evaluated to identify the potential for the dental implant's early osseointegration process, including surface roughness parameter documentation by contact and non-contact methods, surface morphology assessment by scanning electron microscopy, and surface wettability estimation using the sessile drop technique. The obtained results showed that the surface roughness parameters attributed to high osseointegration relevance (Rsk, Rku, and Rsm) were not significantly influenced by laser power, and on the other hand, the scanning speed seems to have the most prevalent effect on surface roughness when exhibiting statistical differences in all evaluated profile roughness parameters except Rvk. The obtained laser-modified surfaces were hydrophilic, with a contact angle in the range of 62.3° to 83.2°.
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Affiliation(s)
- Peter Šugár
- Institute of Production Technologies, Faculty of Materials Science and Technology, Slovak University of Technology, J. Bottu 25, 917 24 Trnava, Slovakia; (R.A.); (J.Š.)
| | - Richard Antala
- Institute of Production Technologies, Faculty of Materials Science and Technology, Slovak University of Technology, J. Bottu 25, 917 24 Trnava, Slovakia; (R.A.); (J.Š.)
| | - Jana Šugárová
- Institute of Production Technologies, Faculty of Materials Science and Technology, Slovak University of Technology, J. Bottu 25, 917 24 Trnava, Slovakia; (R.A.); (J.Š.)
| | - Jaroslav Kováčik
- Slovak Academy of Sciences, Institute of Materials and Machine Mechanics, Dúbravská cesta 9, 845 13 Bratislava, Slovakia;
| | - Vladimír Pata
- Department of Production Engineering, Faculty of Technology, Tomas Bata University, Vavrečkova 5669, 960 01 Zlín, Czech Republic;
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Suzumura T, Matsuura T, Komatsu K, Sugita Y, Maeda H, Ogawa T. Vacuum Ultraviolet (VUV) Light Photofunctionalization to Induce Human Oral Fibroblast Transmigration on Zirconia. Cells 2023; 12:2542. [PMID: 37947620 PMCID: PMC10647316 DOI: 10.3390/cells12212542] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 10/26/2023] [Accepted: 10/27/2023] [Indexed: 11/12/2023] Open
Abstract
Soft tissue adhesion and sealing around dental and maxillofacial implants, related prosthetic components, and crowns are a clinical imperative to prevent adverse outcomes of periodontitis and periimplantitis. Zirconia is often used to fabricate implant components and crowns. Here, we hypothesized that UV treatment of zirconia would induce unique behaviors in fibroblasts that favor the establishment of a soft tissue seal. Human oral fibroblasts were cultured on zirconia specimens to confluency before placing a second zirconia specimen (either untreated or treated with one minute of 172 nm vacuum UV (VUV) light) next to the first specimen separated by a gap of 150 µm. After seven days of culture, fibroblasts only transmigrated onto VUV-treated zirconia, forming a 2.36 mm volume zone and 5.30 mm leading edge. Cells migrating on VUV-treated zirconia were enlarged, with robust formation of multidirectional cytoplastic projections, even on day seven. Fibroblasts were also cultured on horizontally placed and 45° and 60° tilted zirconia specimens, with the latter configurations compromising initial attachment and proliferation. However, VUV treatment of zirconia mitigated the negative impact of tilting, with higher tilt angles increasing the difference in cellular behavior between control and VUV-treated specimens. Fibroblast size, perimeter, and diameter on day seven were greater than on day one exclusively on VUV-treated zirconia. VUV treatment reduced surface elemental carbon and induced superhydrophilicity, confirming the removal of the hydrocarbon pellicle. Similar effects of VUV treatment were observed on glazed zirconia specimens with silica surfaces. One-minute VUV photofunctionalization of zirconia and silica therefore promotes human oral fibroblast attachment and proliferation, especially under challenging culture conditions, and induces specimen-to-specimen transmigration and sustainable photofunctionalization for at least seven days.
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Affiliation(s)
- Toshikatsu Suzumura
- Weintraub Center for Reconstructive Biotechnology, Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA
- Department of Oral Pathology/Forensic Odontology, School of Dentistry, Aichi Gakuin University, Nagoya 464-8650, Japan
| | - Takanori Matsuura
- Weintraub Center for Reconstructive Biotechnology, Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA
| | - Keiji Komatsu
- Weintraub Center for Reconstructive Biotechnology, Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA
| | - Yoshihiko Sugita
- Weintraub Center for Reconstructive Biotechnology, Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA
- Department of Oral Pathology/Forensic Odontology, School of Dentistry, Aichi Gakuin University, Nagoya 464-8650, Japan
| | - Hatsuhiko Maeda
- Department of Oral Pathology/Forensic Odontology, School of Dentistry, Aichi Gakuin University, Nagoya 464-8650, Japan
| | - Takahiro Ogawa
- Weintraub Center for Reconstructive Biotechnology, Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA
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Kitajima H, Hirota M, Iwai T, Mitsudo K, Saruta J, Ogawa T. Synergistic Enhancement of Protein Recruitment and Retention via Implant Surface Microtopography and Superhydrophilicity in a Computational Fluid Dynamics Model. Int J Mol Sci 2023; 24:15618. [PMID: 37958605 PMCID: PMC10649348 DOI: 10.3390/ijms242115618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/12/2023] [Accepted: 10/19/2023] [Indexed: 11/15/2023] Open
Abstract
The exact mechanisms by which implant surface properties govern osseointegration are incompletely understood. To gain insights into this process, we examined alterations in protein and blood recruitment around screw implants with different surface topographies and wettability using a computational fluid dynamics (CFD) model. Compared with a smooth surface, a microrough implant surface reduced protein infiltration from the outer zone to the implant thread and interface zones by over two-fold. However, the microrough implant surface slowed blood flow in the interface zone by four-fold. As a result, compared with the smooth surface, the microrough surface doubled the protein recruitment/retention index, defined as the mass of proteins present in the area per unit time. Converting implant surfaces from hydrophobic to superhydrophilic increased the mass of protein infiltration 2-3 times and slowed down blood flow by up to two-fold in the implant vicinity for both smooth and microrough surfaces. The protein recruitment/retention index was highest at the implant interface when the implant surface was superhydrophilic and microrough. Thus, this study demonstrates distinct control of the mass and speed of protein and blood flow through implant surface topography, wettability, and their combination, significantly altering the efficiency of protein recruitment. Although microrough surfaces showed both positive and negative impacts on protein recruitment over smooth surfaces, superhydrophilicity was consistently positive regardless of surface topography.
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Affiliation(s)
- Hiroaki Kitajima
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA; (H.K.); (M.H.); (J.S.)
- Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA
- Department of Oral and Maxillofacial Surgery, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Kanagawa, Japan; (T.I.); (K.M.)
| | - Makoto Hirota
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA; (H.K.); (M.H.); (J.S.)
- Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA
- Department of Oral and Maxillofacial Surgery/Orthodontics, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama 232-0024, Kanagawa, Japan
| | - Toshinori Iwai
- Department of Oral and Maxillofacial Surgery, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Kanagawa, Japan; (T.I.); (K.M.)
| | - Kenji Mitsudo
- Department of Oral and Maxillofacial Surgery, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Kanagawa, Japan; (T.I.); (K.M.)
| | - Juri Saruta
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA; (H.K.); (M.H.); (J.S.)
- Department of Education Planning, School of Dentistry, Kanagawa Dental University, 82 Inaoka, Yokosuka 238-8580, Kanagawa, Japan
| | - Takahiro Ogawa
- Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA; (H.K.); (M.H.); (J.S.)
- Division of Regenerative and Reconstructive Sciences, UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA
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