| Abstract | OBJECTIVES: To investigate the influence of mouth-motion fatigue on marginal-accuracy of partial-coverage-restorations-(PCRs) of various dental materials. METHODS: Eighty molars were prepared equally and divided into five groups (n=16). PCRs were fabricated of following dental materials: Group-GO=Gold-Pontor-MPF(double dagger), Group-TA=Targis*, Group-EX=IPS-e.max-Press*, Group-EM=IPS-Empress*, Group-PC=ProCAD*/Cerec 3(dagger) ((double dagger)Metalor/*Ivoclar-Vivadent/(dagger)Sirona-Dental-System). Gold-PCRs were cemented conventionally. Residual 64 PCRs were adhesively luted and subjected to masticatory loading (1.2million-cycles, 1.6Hz, 49N) and thermal cycling (5 degrees C/55 degrees C, 60s, dwell-time, 5500cycles). Discrepancies in marginal-accuracy were examined on epoxy replicas (200 x magnification). Statistical analysis was performed by unpaired and paired t-tests (alpha=0.05). RESULTS: After cementing, marginal-accuracy (geometrical mean)[95% confidence limits] was recorded: GO-47[43-51]microm, TA-42[38-45]microm, EX-60[52-67]microm, EM-52[45-60]microm and PC-75[59-94]microm. No significant differences were found between groups GO, TA and EM. Values of Group-EX were significantly higher compared to Group-TA (p=0.04). Group-PC demonstrated significantly decreased marginal-accuracy towards groups GO (p=0.03) and TA (p=0.02). Except for Group-GO (p=0.01), no significant changes in marginal-accuracy were observed after mouth-motion fatigue and thermal cycling (GO-42[38-45]microm, TA-42[38-47]microm, EX-56[49-65]microm, EM-54[46-64]microm and PC-71[59-84]microm). However, Group-GO and Group-EM showed significant deviations in marginal-accuracy after aging (p=0.04). Marginal discrepancies of groups EX and EM were similar (p=1.0). Values of Group-PC were significantly higher when compared to groups GO (p=0.01) and TA (p=0.02). Buccal-lingual marginal discrepancies were significantly higher than mesial-distal in all groups and stages. SIGNIFICANCE: Cast-gold-PCRs demonstrated superior marginal-accuracy, followed by indirect ceromer PCRs. All-ceramic PCRs showed in vitro clinical acceptable marginal widths, even though CAD/CAM fabrication slightly compromised marginal-accuracy. Since preparation margins were not exposed to occlusal loading directly, increased marginal discrepancies due to marginal chipping during mouth-motion fatigue were not experienced. |
| Authors | Christian F J Stappert, Somsak Chitmongkolsuk, Nelson R F A Silva, Wael Att, Joerg R Strub
(Affiliation: Department of Prosthodontics, Albert-Ludwigs-University, Faculty of Dentistry, Freiburg, Germany. christian.stappert at nyu.edu)
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| Journal | Dental materials : official publication of the Academy of Dental Materials
(Dent Mater)
Vol. 24
Issue 9
Pg. 1248-57
(Sep 2008)
ISSN: 0109-5641 England |
| PMID | 18395785
(Publication Type: Comparative Study, Journal Article)
|
| Chemical References |
- Aluminum Silicates
- Ceramics
- Composite Resins
- Dental Alloys
- Dental Materials
- Glass Ionomer Cements
- Gold Alloys
- IPS e.max Press
- IPS-Empress ceramic
- ProCAD Ceramic
- Resin Cements
- ceromer
- dental polyglass
- Dental Porcelain
- Silicate Cement
|
| Topics |
- Aluminum Silicates
(chemistry)
- Bite Force
- Cementation
(methods)
- Ceramics
(chemistry)
- Composite Resins
(chemistry)
- Computer-Aided Design
- Dental Alloys
(chemistry)
- Dental Cavity Preparation
(classification)
- Dental Materials
(chemistry)
- Dental Porcelain
(chemistry)
- Dental Prosthesis Design
- Glass Ionomer Cements
(chemistry)
- Gold Alloys
(chemistry)
- Humans
- Inlays
- Marginal Adaptation (Dentistry)
- Materials Testing
- Resin Cements
(chemistry)
- Silicate Cement
(chemistry)
- Stress, Mechanical
- Surface Properties
- Temperature
- Time Factors
|
