Kumiko Yoshihara1, Noriyuki Nagaoka2, Takumi Okihara3, Manabu Kuroboshi4, Satoshi Hayakawa5, Yukinori Maruo6, Goro Nishigawa7, Jan De Munck8, Yasuhiro Yoshida9, Bart Van Meerbeek10. 1. Center for Innovative Clinical Medicine, Okayama University Hospital, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan. Electronic address: k-yoshi@md.okayama-u.ac.jp. 2. Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan. Electronic address: nagaoka@okayama-u.ac.jp. 3. Division of Chemical and Biological Technology, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan. Electronic address: okihara@cc.okayama-u.ac.jp. 4. Division of Chemical and Biological Technology, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan. Electronic address: mkurohos@cc.okayama-u.ac.jp. 5. Biomaterials Laboratory Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan. Electronic address: satoshi@okayama-u.ac.jp. 6. Department of Occlusion and Removable Prosthodontics, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan. Electronic address: ykmar@md.okayama-u.ac.jp. 7. Department of Occlusion and Removable Prosthodontics, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan. Electronic address: goro@md.okayama-u.ac.jp. 8. BIOMAT, Department of Oral Health Research, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Kapucijnenvoer 7 blok a bus 7001, B-3000 Leuven, Belgium. Electronic address: jan.demunck@med.kuleuven.be. 9. Department of Biomaterials and Bioengineering, Graduate School of Dental Medicine, Hokkaido University, Kita 13, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8586, Japan. Electronic address: yasuhiro@den.hokudai.ac.jp. 10. BIOMAT, Department of Oral Health Research, KU Leuven (University of Leuven) & Dentistry, University Hospitals Leuven, Kapucijnenvoer 7 blok a bus 7001, B-3000 Leuven, Belgium. Electronic address: bart.vanmeerbeek@med.kuleuven.be.
Abstract
OBJECTIVE: The functional monomer 10-MDP has been considered as one of the best performing functional monomers for dental adhesives. Different adhesives containing 10-MDP are commercially available, among which many so-called 'universal' adhesives. We hypothesize that the quality of the functional monomer 10-MDP in terms of purity may affect bonding performance. METHODS: We therefore characterized three different 10-MDP versions (10-MDP_KN provided by Kuraray Noritake; 10-MDP_PCM provided by PCM; 10-MDP_DMI provided by DMI) using NMR, and analyzed their ability to form 10-MDP_Ca salts on dentin using XRD. The 'immediate' and 'aged' micro-tensile bond strength (μTBS) to dentin of three experimental 10-MDP primers was measured. The resultant interfacial adhesive-dentin ultra-structure was characterized using TEM. RESULTS: NMR disclosed impurities and the presence of 10-MDP dimer in 10-MDP_PCM and 10-MDP_DMI. 10-MDP_PCM and 10-MDP_DMI appeared also sensitive to hydrolysis. 10-MDP_KN, on the contrary, contained less impurities and dimer, and did not undergo hydrolysis. XRD revealed more intense 10-MDP_Ca salt deposition on dentin induced by 10-MDP_KN. The adhesive based on the experimental 10-MDP_KN primer resulted in a significantly higher 'immediate' bond strength that remained stable upon aging; the μTBS of the experimental 10-MDP_PCM and 10-MDP_DMI adhesives significantly dropped upon aging. TEM revealed thicker hybridization and more intense nano-layering for 10-MDP_KN. SIGNIFICANCE: It was concluded that primer impurities and the presence of 10-MDP dimer affected not only hybridization, but also reduced the formation of 10-MDP_Ca salts and nano-layering. 10-MDP in a high purity grade is essential to achieve durable bonding.
OBJECTIVE: The functional monomer 10-MDP has been considered as one of the best performing functional monomers for dental adhesives. Different adhesives containing 10-MDP are commercially available, among which many so-called 'universal' adhesives. We hypothesize that the quality of the functional monomer 10-MDP in terms of purity may affect bonding performance. METHODS: We therefore characterized three different 10-MDP versions (10-MDP_KN provided by Kuraray Noritake; 10-MDP_PCM provided by PCM; 10-MDP_DMI provided by DMI) using NMR, and analyzed their ability to form 10-MDP_Ca salts on dentin using XRD. The 'immediate' and 'aged' micro-tensile bond strength (μTBS) to dentin of three experimental 10-MDP primers was measured. The resultant interfacial adhesive-dentin ultra-structure was characterized using TEM. RESULTS: NMR disclosed impurities and the presence of 10-MDP dimer in 10-MDP_PCM and 10-MDP_DMI. 10-MDP_PCM and 10-MDP_DMI appeared also sensitive to hydrolysis. 10-MDP_KN, on the contrary, contained less impurities and dimer, and did not undergo hydrolysis. XRD revealed more intense 10-MDP_Ca salt deposition on dentin induced by 10-MDP_KN. The adhesive based on the experimental 10-MDP_KN primer resulted in a significantly higher 'immediate' bond strength that remained stable upon aging; the μTBS of the experimental 10-MDP_PCM and 10-MDP_DMI adhesives significantly dropped upon aging. TEM revealed thicker hybridization and more intense nano-layering for 10-MDP_KN. SIGNIFICANCE: It was concluded that primer impurities and the presence of 10-MDP dimer affected not only hybridization, but also reduced the formation of 10-MDP_Ca salts and nano-layering. 10-MDP in a high purity grade is essential to achieve durable bonding.
Authors: Mohamed M Awad; Feras Alhalabi; Mohamed Bamuqadm; Abdulmalik Alhoti; Abdulilah Almasaad; Ali Robiaan; Ahmed Almahdy; Ali Alrahlah; Mohammed H Ahmed Journal: Odontology Date: 2022-09-29 Impact factor: 2.885