Notice bibliographique
Résumé
Glass polyalkenoate cements (GPCs) have potential for skeletal cementation. Unfortunately, commercial GPCs all contain and subsequently release aluminum ions, which have been implicated in degenerative brain disease. The purpose of this research was to create aluminum free GPCs constructed from silicate (SiO2)-calcium (CaO)-zinc (ZnO), glasses mixed with polyacrylic acid (PAA200) in order to evaluate the potential of these novel GPCs for attaching titanium miniplates directly to the skull, a clinical procedure known as cranioplasty. Three glasses were formulated: KBT01 SiO2-CaO-ZnO-sodium (Na2O) glass, KBT02 SiO2-CaO-ZnO-Na2Ogermanium (GeO2), with a 0.03 mol% GeO2 substitution for ZnO and KBT03 SiO2-CaO-ZnONa2O-GeO2, with a 0.06 mol% GeO2 substitution for ZnO in glass structure. X-ray diffraction (XRD) and particle size analysis (PSA) confirmed that all glasses were completely amorphous with similar mean particle sizes. Each glass in the series was mixed with 50 wt% a patented SiO2- CaO-ZnO-strontium (SrO) glass composition, BT101, and subsequently mixed with PAA200 at 50 wt% addition to produce a series of cements. The addition of Ge to the glass series resulted in decreased working times (~142 s to 112 s) and setting times (~807 to 448 s) for the cements manufactured from them. This was due to the increase in crosslink formation during the setting reaction between the Ge-containing glasses and the PAA200. Regarding ion release, Atomic Absorption Spectroscopy (AAS) determined Zn2+ ion release to be 9.56, 8.02 and 5.83 ppm after 30 days for KBT01, KBT02 and KBT03 cements respectively. Germanium ions were not release from the KBT01 cement since the glasses it was formulated from did not contain Ge4+. KBT02 and KBT03 cements released 1.23 ppm and 1.94 ppm of Ge4+ ions after 30 days. The mechanical properties (compressive ~ σc, and biaxial flexural strength ~ σf) of the resulting cements were examined over three time modalities, 1, 7 and 30 days. σc of the cements ranged from ~27- 56 MPa, while σf ranged from ~17-33 MPa. Both strength modalities increased with maturation and increasing Ge content, as Ge may facilitate improved chemical bonding between the COO-groups, thus creating stronger cements in KBT02 and KBT03. The bond strength of the titanium cylinder (Ti) to the bone that it was attached to by the cements increased from ~0.23MPA to 0.63 MPa respectively from placement up to 14 days maturation. Failure of these constructs occurred at the interface between the Ti cylinder and the cement. The results of this research indicate that, due to their novel composition, Ge-based GPCs have suitable handling properties, strengths and adhesiveness for potential in cranioplasty fixation.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».