Language：Japanese   Publisher：Scientific Reports  

This study aimed to compare the 2-year clinical outcomes of polyetheretherketone (PEEK) and hybrid resin crowns placed on molars. Patients who received PEEK (P-Cr) and hybrid resin (H-Cr) crowns at Hiroshima University Hospital between 2016 and 2021 were evaluated in 2024 for crown conditions, including loss, fractures, and occlusal wear. No cases of crown debonding or fracture were observed in the P-Cr group. In contrast, the H-Cr group had 10 cases of loss and 4 cases of fractures. The P-Cr group demonstrated significantly fewer cases of crown debonding than the H-Cr group. Occlusal wear was observed in most crowns in the P-Cr group. Compared to the hybrid resin crowns, the PEEK crowns had a lower risk of fracture and debonding and retained long-term functionality; however, surface roughness and color changes were observed, suggesting that they may not be ideal for patients with particularly high esthetic demands. Nevertheless, physiological occlusal relationships and functionality were preserved, indicating that PEEK crowns could be a viable option for restoring molar defects.

DOI： 10.1038/s41598-025-95075-x

Scopus

PubMed

Language：English   Publisher：The Japanese Society for Dental Materials and Devices  

<p>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.</p>

DOI： 10.4012/dmj.2023-278

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PubMed

CiNii Research

Language：English   Publisher：(一社)日本歯科理工学会  

適切な寸法安定性を示すレジン系パターン材料を創出するため、光重合型パターン用レジンの実験品を製造した。本実験品の成分とするポリマーにはポリ(メタクリル酸n-ブチル)またはポリ(メタクリル酸イソブチル)(PiBMA)を、モノマーにはメタクリル酸を採用した。各種の物理的特性を測定し、商用利用可能なパターン用レジンであるPalavit G(対照品)と比較した。調製した実験品のうちのいくつかは、焼却残渣量が対照品よりも少なかった。ビッカース硬さと曲げ強さの値は、どの実験品でも対照品より低かった。PiBMAを使用したどの実験品も、体積重合収縮率は対照品より低くなった。こうした結果から、PiBMAを主成分とする光重合式アクリルレジン材料は、ろう着中のパターン形成とインデックス製作に有用である可能性が示唆された。

Language：English   Publisher：(一社)歯科基礎医学会  

ポリエーテルエーテルケトン(PEEK)製の冠が有する放射線不透過の特性は、誤って嚥下・吸引してしまった時の位置の特定、および二次齲蝕の発見に利用可能なものであるか実験した。歯列模型の下顎左側第1大臼歯を支台歯とし、PEEK製、ハイブリッドレジン製、ジルコニア製、金銀パラジウム合金製の冠を製造した。これらの冠を、口腔内X線、胸部X線、コーンビームCT、マルチスライスCTの各撮像法で画像を取得した。その結果、PEEK冠の不透過特性は最も低く、2種のCT画像ではアーチファクトが大変少なくなることが示された。その一方で、PEEK冠のCT値はハイブリッドレジン冠と比較してもほとんど低下しておらず、ジルコニア冠および合金製の全部鋳造冠と比べた時は相当に低下していた。次の実験として、模型支台歯の頬側面と遠心面に模擬窩洞を作製し冠を設置した二次齲蝕モデルの口腔内X線画像を取得した。その画像から窩洞の存在を検出することは可能であった。

Language：English   Publisher：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

Language：Japanese   Publisher：(株)ヒョーロン・パブリッシャーズ  

Language：Japanese   Publisher：広島大学歯学会  

Language：Japanese  

Language：Japanese  

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Language：Japanese