Fracture resistance and failure modes of CEREC endo-crowns and conventional post and core-supported CEREC crowns

被引:75
作者
Chang, Chia-Yu [1 ]
Kuo, Jau-Shing [1 ]
Lin, Yang-Sung [2 ]
Chang, Yen-Hsiang [1 ]
机构
[1] Chang Gung Mem Hosp, Dept Operat Dent, Tao Yuan 33345, Taiwan
[2] Chang Gung Univ, Dept Mech Engn, Tao Yuan, Taiwan
关键词
CAD-CAM; CEREC; endo-crown; failure modes; fracture resistance; ENDODONTICALLY TREATED TEETH; OF-THE-LITERATURE; MAXILLARY PREMOLARS; BIOMECHANICAL CONSIDERATIONS; RESTORATIVE PROCEDURES; MOISTURE-CONTENT; CERAMIC CROWNS; BITE FORCE; DENTIN; COMPOSITE;
D O I
10.1016/S1991-7902(09)60016-7
中图分类号
R78 [口腔科学];
学科分类号
1003 ;
摘要
Background/purpose: The purpose of this in vitro study was to compare the fracture resistance and failure modes of CEREC endo-crowns with the CEREC classic designed crown supported with glass fiber-reinforced composite posts and composite cores. The influences of thermal cycling and fatigue loading on both types of restorations were also investigated. Materials and methods: Twenty extracted intact maxillary premolars were randomly divided into two groups (C and E). The crown portion of the specimens was removed to 1.5 mm above the cementoenamel junction (CEJ). All specimens were endodontically treated with a nickel-titanium rotary system and obturated with gutta-percha by a vertical compaction technique. In group C (n=10), teeth were restored with glass fiber-reinforced composite posts and composite cores with a 1.0-mm wide circumferential shoulder margin at the CEJ and a 1.5-mm ferrule. In group E (n=10), teeth were prepared for fabrication of CEREC endo-crowns. Both types of ceramic crowns were produced from ProCAD ceramic blocks utilizing a CEREC 3D CAD-CAM unit, and these were bonded to the preparations with an adhesive system and composite resin cement. Teeth were thermally cycled (2000 cycles of 5 degrees C/55 degrees C with a dwell time of 30 seconds,) and fatigue loaded (20,000 cycles at 5 kg and 3 Hz) in a custom-made fatigue simulator. All specimens were loaded in a universal testing machine with a cross-head speed of 0.5 mm/s until fracture occurred. Fracture resistance and failure modes were statistically evaluated with a t test and chi(2) test. Results: The mean fracture resistance standard deviation was recorded as follows: 1163.30 +/- 163.15N for group C and 1446.68 +/- 200.34N for group E. A significant difference was found between groups with respect to fracture resistance (P<0.05). Regarding failure modes, most specimens of both groups exhibited unfavorable fractures, and no significant difference was found between the two groups. Conclusion: The bonded ceramic endo-crowns showed a significantly higher fracture resistance than the classic reinforced and designed group and, therefore, offer a feasible alternative for severely damaged teeth.
引用
收藏
页码:110 / 117
页数:8
相关论文
共 39 条
[1]  
Adams T, 2000, Pract Periodontics Aesthet Dent, V12, P105
[2]  
Bindl A, 1999, J Adhes Dent, V1, P255
[3]  
Bindl A, 2005, INT J PROSTHODONT, V18, P219
[4]  
Bitter K, 2007, AM J DENT, V20, P353
[5]   Effects of surface finish and fatigue testing on the fracture strength of CAD-CAM and pressed-ceramic crowns [J].
Chen, HY ;
Hickel, R ;
Setcos, JC ;
Kunzelmann, KH .
JOURNAL OF PROSTHETIC DENTISTRY, 1999, 82 (04) :468-475
[6]  
DEESRI W, 2003, P 81 GEN SESS INT AS
[7]  
DeLong R, 1985, Dent Mater, V1, P238, DOI 10.1016/S0109-5641(85)80050-6
[8]  
Dietschi D, 2008, QUINTESSENCE INT, V39, P117
[9]  
Dietschi D, 2007, QUINTESSENCE INT, V38, P733
[10]   Ex vivo fracture resistance of direct resin composite complete crowns with and without posts on maxillary premolars [J].
Fokkinga, WA ;
Le Bell, AM ;
Kreulen, CM ;
Lassila, LVJ ;
Vallittu, PK ;
Creugers, NHJ .
INTERNATIONAL ENDODONTIC JOURNAL, 2005, 38 (04) :230-237