Effect of two self-adhesive cements on marginal adaptation and strength of esthetic ceramic CAD/CAM molar crowns
| Autor: | Thomas Attin, Andreas Bindl, Andreas Ender, Daniel Wolf, Werner H. Mörmann, Till N. Göhring |
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| Přispěvatelé: | University of Zurich, Mörmann, Werner |
| Jazyk: | angličtina |
| Rok vydání: | 2009 |
| Předmět: |
Molar
Dental Stress Analysis Materials science medicine.medical_treatment Dentistry 610 Medicine & health Crown (dentistry) stomatognathic system 10066 Clinic of Conservative and Preventive Dentistry medicine Dentin Humans Ceramic Dental Restoration Failure General Dentistry Orthodontics Cement Polycarboxylate Cement Crowns business.industry Dental Bonding Dental Marginal Adaptation 3500 General Dentistry Resin Cements Self adhesive medicine.anatomical_structure Dental Prosthesis Design visual_art Dentin-Bonding Agents visual_art.visual_art_medium Adhesive Stress Mechanical Zinc Oxide business Magnesium Oxide |
| DOI: | 10.5167/uzh-29357 |
| Popis: | PURPOSE: This study evaluated the effects of adhesive cements on marginal adaptation and fracture resistance of ceramic molar crowns. MATERIALS AND METHODS: Seventy-five extracted maxillary molars were selected. The occlusal morphology of 15 molars (control) was scanned and transferred to the crowns in the test groups by CAD/CAM. Sixty molars received full-coverage crown preparations with 6-degree axial taper, 1.0-mm shoulder, and 2.0-mm occlusal reduction. They were assigned to four groups, and pulpal pressure was simulated. The 15 crowns in each test group were seated with resin-based self-adhesive cements, Rely-X (RX) and Multilink (MS), one multistep bonded adhesive luting composite resin, Variolink (VL), and glass-ionomer cement, Ketac Cem (KC). Test and control molars were subjected to thermal and mechanical fatigue stress (TMS: 12,000 x 5 degrees C to 50 degrees C; 2.4 million x 49 N) for 18 days in a masticator. Marginal adaptation ["continuous margin%" (CM%)] of the crowns was determined by scanning electron microscopy (200x). Finally, molars were occlusally loaded until fracture in a testing machine, and fracture load (N) was recorded. Marginal adaptation and strength data were statistically analyzed. RESULTS: TMS significantly (p < 0.001) reduced CM% in all groups. After TMS, CM% at the cement-dentin interface was significantly (p < 0.001) higher for RX than for all other cements. At the crown-cement interface both self-adhesive cements MS and RX had significantly better CM% than VL (p < 0.05) and KC (p < 0.001). Fracture resistance of natural untreated molars was significantly (p < 0.001) higher than that of experimental crowns. Fracture resistance of RX cemented crowns was significantly (p < 0.05) higher than that of other crowns. Occlusal morphology significantly influenced fracture resistance (p < 0.05). CONCLUSIONS: Self-adhesive cement RX offers a valid alternative to multistep resin-based luting composite with respect to marginal adaptation to dentin and fracture resistance. The latter is also influenced by occlusal morphology, necessitating careful monitoring of occlusal contacts. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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