Effect of application technique and coping design on the retention of cemented implant-supported crowns
Notice bibliographique
Résumé
STATEMENT OF PROBLEM: Cement-retained implant crowns are susceptible to biological complications from excess cement extrusion and unpredictable retention because of variations in cementation technique and coping design. However, the biomechanical and hydrodynamic effects of cement volume, application method, and venting features on retention and marginal seal integrity remain inadequately characterized. PURPOSE: The purpose of this in vitro study was to investigate how cement volume, application method, and coping design affect crown retention and cement extrusion. MATERIAL AND METHODS: Fifty computer numerical control (CNC)-milled stainless-steel copings were machined with an average +133 µm tolerance fit on 3-mm hexagonal abutments and were divided equally into 5 groups consisting of closed-end coping with measured cement, no aging (CE-MC-NA); closed-end coping with filled cement, no aging (CE-FC-NA); closed-end coping with measured cement, aged (CE-MC-AG); closed-end coping with filled cement, aged (CE-FC-AG); and open-vented coping with filled cement, aged (OV-FC-AG). Assemblies were weighed before cementation (W₁), after cementation (W₂), and after excess cement removal (W₃). Cement extrusion=(W₂ - W₃) - W₁ and net retained cement =W₃ - W₁. For measured-coated copings, a controlled volume of cement (not exceeding the internal void volume) was applied using a brush, and the net cement delivered was calculated based on weight differences before and after cementation. Aging consisted of 500 thermocycles (5 °C to 55 °C, 30-second dwell). Marginal integrity was evaluated using dye penetration and microscopic inspection, and retention strength (N) was measured using a dislodgement test. Analyses used Mann‑Whitney U, Kruskal‑Wallis with Bonferroni‑adjusted planned contrasts, and a 2×2 factorial ANOVA. RESULTS: Group CE-MC-NA had significantly lower retained cement weight than group CE-FC-NA (P<.001), with comparable retention strength (P>.05). After aging, group CE-MC-AG showed significantly less retained cement than group CE-FC-AG (P<.001), and both retained less cement than group OV-FC-AG (P<.001). Retention strengths were similar for groups CE-MC-AG and CE-FC-AG (P>.05), while OV-FC-AG exhibited superior retention (P<.001). No marginal leakage was detected in any group. CONCLUSIONS: Under the experimental conditions, measured thin-film cementation combined with vented or geometrically optimized copings provided a biomechanically effective and biologically safer alternative to traditional bulk-filling techniques. By standardizing application and leveraging interface design, this protocol should redefine luting cement as a precise sealing interface rather than a bulk retentive material.
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 | 0,001 | 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) | 0,000 | 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 ».