Marginal Fit of Single-Crown and Three-Unit Fixed Dental Prostheses Fabricated From Digital and Conventional Impressions: An In Vitro Cross-Sectional Study
Notice bibliographique
Résumé
Introduction: With the current surge into digital dentistry, several options are available for clinicians, for example, when providing indirect restorations. There is a need for evidence on the quality of fixed dental prostheses (FDPs) fabricated using either digital or conventional impressions. This study aimed to evaluate the marginal fit of single-crown and three-unit FDP frameworks fabricated from digital and conventional impressions. Materials and methods: Crown preparations were made on a maxillary typodont model (KaVo Dental GmbH, Biberach, Germany) on the right central incisor for a single-crown framework and the right first premolar and first molar for a three-unit framework to replace the second premolar. Four scanners (Dental Wings (DW, Straumann Group, Montreal, Canada), Carestream 3600 (CS, Carestream Dental, Atlanta, GA, USA), Medit i700 (M700, MEDIT Corp., Seoul, Republic of Korea), and Medit i500 (M500, MEDIT Corp.)) were used to record digital impressions of the preparations. Conventional impressions using polyether monophase impression material were also made, and stone casts were fabricated using high-strength stone and scanned using a laboratory scanner (Dental Wings, Straumann Group). Stereolithography files and computer-aided design and computer-aided manufacturing (CAD-CAM) were used to produce 50 zirconia FDPs (25 each of single crowns and three-unit frameworks). The marginal fit of the prostheses was determined by marginal gap measurements while seated on the typodont, a gap of ≤150µm being deemed acceptable. Results were summarized as means, standard deviations, medians, and interquartile ranges (IQRs). The independent t-test and one-way ANOVA followed by Tukey's post hoc test for means and Kruskal-Wallis test followed by Dunn’s post hoc test for medians were performed for hypothesis testing at α<0.05. Results: The respective marginal gap measurements for single-crown and three-unit FDPs were 151.3±60.1µm and 153.9±50.1µm (polyether), 185.0±63.7µm and 224.2±81.7µm (DW), 177.1±81.3µm and 146.4±44.9µm (CS), 158.0±48.7µm and 184.3±86.2µm (M700), and 195.9±61.7µm and 202.8±71.1µm (M500). The marginal gap measurements of single crowns were significantly different among the five impression methods (F = 2.54, p = 0.042; χ2 = 14.68, p = 0.005) but not among the four digital methods (F = 1.83, p = 0.146), with the specific differences being between polyether and DW (p<0.01) and between polyether and M500 (p<0.001). The marginal gap measurements of the three-unit prostheses were significantly different among all five impression methods (F = 13.52, χ2 = 46.64, p<0.001) and the four digital methods (F = 12.32, p<0.001). The specific differences were between polyether and DW (p<0.001), M700 (p=0.02), and M500 (p<0.001), respectively; between CS and the other three digital methods (DW, p<0.001; M700, p=0.024; M500, p<0.001); and between DW and M700 (p=0.016). Conclusion: Considering the means and standard deviations, all five impression techniques produced FDPs with acceptable marginal gap measurements. Significant differences were observed between conventional and digital impression techniques, with polyether and CS producing single-crown and three-unit FDPs having the least marginal gaps, respectively.
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Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,002 | 0,002 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,001 |
| Méta-épidémiologie (sens large) | 0,000 | 0,001 |
| Bibliométrie | 0,001 | 0,001 |
| Études des sciences et des technologies | 0,000 | 0,001 |
| Communication savante | 0,000 | 0,001 |
| Science ouverte | 0,000 | 0,001 |
| Intégrité de la recherche | 0,001 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,003 | 0,001 |
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 source (Gemma direct ou Codex distillé), 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 ».