The Fracture Resistance of Endodontically Treated Maxillary Centrals Restored With Laminate Veneers Versus All Ceramic Crowns

Abstract

Endodontically treated teeth have been a high risk of failure due to presence of certain factors than that of vital teeth; these factors are summarized as loss of tooth structure, decrease moisture content and brittleness. Great controversy exists regarding the best type of final restoration of upper centrals to restore function, esthetic demand and durability.Thus, this in vitro study was designed to evaluate the fracture resistance of endodontically treated upper centralsrestored with different restorative techniques. A total of twenty-five freshly extracted maxillary central incisors, free of cracks, fracture or caries and with approximate dimensional similarity were used in this study.All the teeth were endodontically treated with the same technique to be standardized and obturated with gutta percha and eugenol free sealer.Then, the teeth were mounted and centralized in acrylic blocks to be prepared to receive restorations. Teeth were grouped into five groups; each group is consisting of five samples; I. GP I: control group, where all samples were just endodontically treated with the access cavities were filled with composite resin. II. GPII: the samples were prepared to be restored with indirect composite veneers. III. GP III: the samples were prepared to be restored ceramic veneers. IV. GP IV: the samples were prepared to be restored with full coverage ceramic crown without fiber post. V. GP V: the samples were prepared to be restored with full coverage ceramic crown with fiber post. Then, all samples were statically compression loaded until fracture at a speed of 1 mm/ min, the data of fracture resistance was collected and tabulated and statistically analyzed to detect the best restoration technique of all groups. There was no statistically significant difference between laminate veneergroups and full coverage groups. The highest mean value of fracture resistancewas found inlaminate veneergroups. While the lowest mean value of fracture resistance was found in full coveragegroups. Control group showed the highest mean valueof fracture resistance followed byGroup Vfollowed by Group II and Group III. While the lowest mean value of fracture resistance was found in Group IV. Within the limitation of this study the following conclusion could be drawn; 1. Endodontically treated teeth without extracoronal restoration showed the highest fracture resistance. 2. The presence of post increases the fracture resistance of endodontically treated teeth. 3. Full coverage crowns are highly invasive and have an adverse effect on the fracture resistance.