Kadokawa A., Murahara S., Kono H., Uenodan A., Fuchida A., Nishio F., Minami H. . Physical properties of experimental light-curing pattern resins based on poly (n-butyl methacrylate) or poly(i2023 · 記述言語： 英語 掲載種別： 研究論文（学術雑誌） 出版者・発行元： 一般社団法人 日本歯科理工学会 Experimental light-curing pattern resins were fabricated to produce pattern resin materials with adequate dimensional stability. The light-curing pattern resins consisted of poly(n-butyl methacrylate) or poly(iso-butyl methacrylate) (PiBMA) polymers and methacrylate monomers. The physical properties, amount of residual ash after burning, Vickers hardness, flexural strength, and volumetric polymerization shrinkage of each material were determined. The data obtained for the prepared resins were compared with those of a commercially available pattern resin, Palavit G (PG). A lower amount of residual ash was observed for some of the prepared resins than for PG. The Vickers hardness and flexural strength values of all experimental resins were lower than those of PG. The volumetric polymerization shrinkage of all the experimental resins based on PiBMA was lower than that of PG. These results suggest that acrylic light-curing resin materials based on PiBMA may be useful for patterning and indexing during soldering. DOI： 10.4012/dmj.2023-278 Scopus PubMed CiNii Research
Nishio F, Morita K, Doi K, Kato M, Abekura H, Yamaoka H, Kakimoto N, Tsuga K . Radiopaque properties of polyetheretherketone crown at laboratory study. . Journal of oral biosciences652023 · 記述言語： 英語 掲載種別： 研究論文（学術雑誌） 出版者・発行元： Journal of Oral Biosciences Objectives: There have been no reports on the radiopaque properties of new polyetheretherketone (PEEK) crowns for locating crowns during accidental ingestion or aspiration and detection of secondary caries, which is essential information for clinical application. This study aimed to investigate whether the radiopaque properties of PEEK crowns could be used to identify the site of accidental ingestion or aspiration and detect secondary caries. Methods: Four types of crowns were fabricated: three non-metal crowns (PEEK, hybrid resin, and zirconia) and one full metal cast crown (gold-silver-palladium alloy). Initially, the images for these crowns were compared using intraoral radiography, chest radiography, cone-beam computed tomography (CBCT), and multi-detector computed tomography (MDCT); computed tomography (CT) values were calculated. Subsequently, the images for the crowns placed on the secondary caries model with two artificial cavities were compared using intraoral radiography. Results: The PEEK crowns displayed the lowest radiopaque properties on radiography and very few artifacts were observed on CBCT and MDCT. On the other hand, the CT values of the PEEK crowns were a little lower than those of the hybrid resin crowns and considerably lower than the zirconia and full metal cast crowns. The cavity could be detected in the PEEK crown-placed secondary caries model through intraoral radiography. Conclusions: This simulated study of radiopaque properties with four types of crowns suggested that a radiographic imaging system can be used to identify the site of accidental ingestion and aspiration of PEEK crowns and to detect secondary caries of the abutment tooth within a PEEK crown. DOI： 10.1016/j.job.2023.05.002 Scopus PubMed
銀イオンを活用する安全な新規抗菌性PEEK冠の開発2022 · 配分額： 4550000円 （ 直接経費： 3500000円 、 間接経費： 1050000円 ） 本研究は、高い材料加工性をもち、優れた物性を持つポリエーテルエーテルケトン（PEEK）と高い抗菌作用をもつ銀ナノ粒子に着目し、これらを配合した抗菌作用をもつ全く新しい歯冠修復材を開発することを目的とする。生体安全性や抗菌活性に加えて接着強さ、機械的強度、表面性状を解析し、抗菌試験を行うことでPEEK冠の臨床応用の可能性を明らかにする。 2022年度は、CAD/CAMによるPEEK冠の臨床研究に着手し、患者20名に対して歯冠色PEEK冠を装着し6ヶ月間の経過観察を行い、経過は良好であった旨を報告した（Clinical report of six month follow up after cementing PEEK crown on molars）。PEEKの表面性状が菌の付着に影響を及ぼしていると考え、表面性状の分析を行い、銀ナノ粒子を混和した試験片のミュータンス菌に対する抗菌試験を行った。結果、PEEKは既存の臨床にて用いられている研磨用バーを用いて研磨を行うことで0.2マイクロメートル以下の表面粗さを示すようになった。過去の報告より、歯冠修復物を含む口腔内装置の表面粗さは細菌付着やプラーク堆積、患者による舌感の観点から表面粗さ0.2マイクロメートル以下が望ましいとされている。そのため、PEEKは臨床にて用いるにあたり十分な表面の滑沢さを得られることが明らかになった。この内容は現在論文執筆中である。また、歯冠色PEEKのレントゲン不透過性についてもレントゲン撮影を行い、医科用CT装置にて撮影を行った際にハレーション等見られず誤飲誤嚥が起こった際には胸部CT撮影が望ましいことが明らかになった。前述の内容は現在論文投稿中である。
