Bin Lee1, Jae-Sung Kwon2, Muhammad Waqas Khalid3, Kwang-Mahn Kim2, Joonhui Kim4, Kyoung Mook Lim5, Soon Hyung Hong6. 1. Korea Institute for Rare Metal, Korea Institute of Industrial Technology, Yeonsu-gu, Incheon 21999, Republic of Korea. Electronic address: lbin@kitech.re.kr. 2. Department and Research Institute of Dental Biomaterials and Bioengineering, Yonsei University College of Dentistry, Seodaemun-gu, Seoul 03722, Republic of Korea. 3. Korea Institute for Rare Metal, Korea Institute of Industrial Technology, Yeonsu-gu, Incheon 21999, Republic of Korea; Department of Industrial Materials and Smart Manufacturing Engineering, University of Science and Technology, Daejeon, 34113, Republic of Korea. 4. Center for R&D Performance Diffusion, Korea Institute of Science & Technology Evaluation and Planning (KISTEP), Eumseong-gun, Chungcheongbuk-do, 27740, Republic of Korea. 5. Korea Institute for Rare Metal, Korea Institute of Industrial Technology, Yeonsu-gu, Incheon 21999, Republic of Korea. 6. Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Yuseong-gu, Daejeon 34141, Republic of Korea. Electronic address: shhong@kaist.ac.kr.
Abstract
OBJECTIVE: The main goal of this research was to demonstrate the potential value of boron nitride nanoplatelets (BNNPs), which have excellent mechanical properties and biocompatibility, as a suitable reinforcement for dental materials. METHODS: The BNNPs were prepared by exfoliating h-BN via high-energy ball-milling and dispersion on a zirconia matrix. Then the composite powder was consolidated using spark plasma sintering. Fracture toughness, flexural strength and wear resistance were the mechanical properties explored. Agar diffusion-based biocompatibility testing was carried out. Low temperature degradation tests were also performed in a steam environment in an autoclave. RESULTS: The BNNPs dispersed zirconia exhibited improved strength (up to 27.3%), and fracture toughness was also increased (up to 37.5%) with the addition of 1-1.5 vol.% BNNPs. Tribological properties were also enhanced by the addition of BNNPs. The cytotoxicity tests confirmed that the BNNPs do not have obvious toxicity. The accelerated low-temperature degradation experiment revealed the barrier properties of the BNNPs, whose addition almost fully inhibited the degradation of the zirconia matrix in a humid environment. SIGNIFICANCE: The main contribution of this study is the introduction of an advanced material, BNNP, which can be used as a biocompatible reinforcement for dental materials, resulting in enhanced mechanical properties of the system due to its unique structure and extraordinary properties.
OBJECTIVE: The main goal of this research was to demonstrate the potential value of boron nitride nanoplatelets (BNNPs), which have excellent mechanical properties and biocompatibility, as a suitable reinforcement for dental materials. METHODS: The BNNPs were prepared by exfoliating h-BN via high-energy ball-milling and dispersion on a zirconia matrix. Then the composite powder was consolidated using spark plasma sintering. Fracture toughness, flexural strength and wear resistance were the mechanical properties explored. Agar diffusion-based biocompatibility testing was carried out. Low temperature degradation tests were also performed in a steam environment in an autoclave. RESULTS: The BNNPs dispersed zirconia exhibited improved strength (up to 27.3%), and fracture toughness was also increased (up to 37.5%) with the addition of 1-1.5 vol.% BNNPs. Tribological properties were also enhanced by the addition of BNNPs. The cytotoxicity tests confirmed that the BNNPs do not have obvious toxicity. The accelerated low-temperature degradation experiment revealed the barrier properties of the BNNPs, whose addition almost fully inhibited the degradation of the zirconia matrix in a humid environment. SIGNIFICANCE: The main contribution of this study is the introduction of an advanced material, BNNP, which can be used as a biocompatible reinforcement for dental materials, resulting in enhanced mechanical properties of the system due to its unique structure and extraordinary properties.