Comparison of fracture resistance of pulpless teeth restored with fiber reinforced composite posts and three kinds of resin core material / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To compare the fracture resistances of pulpless teeth restored with FRC (Fiber Reinforced Composite) posts and three kinds of resin core material.</p><p><b>METHODS</b>A total of 42 recently extracted upper incisors were randomly divided into 3 groups. Group A was restored with prefabricated glass-fiber posts and Artglass polymer core; group B with prefabricated glass-fiber posts and Charisma composite resin core; and group C with prefabricated glass-fiber posts and AB composite resin core. In every group, the core material was processed by hot-press and non hot-press respectively. The posts size and shape were identical in the 3 groups. All teeth were fully covered with polycarbonate resin crowns. Fracture resistance was measured by applying point force at 130 degrees to the long axis of the teeth on an universal testing machine.</p><p><b>RESULTS</b>Mean fracture threshold was 505.4 N +/- 42.0 N and 564.1 N +/- 41.7 N in group A, 411.3 N +/- 23.3 N and 315.3 N +/- 19.1 N in group B and 358.4 N +/- 36.1 N and 423.4 N +/- 47.5 N in group C. In all groups, there was no posts fracture and polycarbonate resin crowns fragmentation.</p><p><b>CONCLUSION</b>The composite restoration of FRC posts combined with resin core and resin crown can improve the fracture resistance of the pulpless roots. The strength of resin core material can be increased by hot-press methods.</p>

Clinical evaluation of 546 tetracycline-stained teeth treated with Cerinate laminate veneers / 中华口腔医学杂志

<p><b>OBJECTIVE</b>The purpose of this study was to evaluate the clinical result of 546 tetracycline-stained teeth corrected with Cerinate porcelain laminate veneer system for esthetic purpose.</p><p><b>METHODS</b>546 tetracycline-stained teeth were corrected with Cerinate porcelain veneer system, and bonded with Ultra Bond resin cement. The restorations were recalled after 0.5 year, 1.5 years and 2.5 years, respectively. modified Ryge criteria were used to evaluate the veneers marginal adaptation, interfacial staining, secondary caries, postoperative sensitivity and the patients' satisfaction with the shade of the restorations.</p><p><b>RESULTS</b>this study found that 99% veneers had excellent marginal adaptations; and less than 1% veneers were rebonded after debond in the first half year application; the color of the veneers was stable and no evident staining was found. Almost all patients were satisfied with their restoration color after 1 year's application.</p><p><b>CONCLUSION</b>The research indicated that Cerinate porcelain veneer restoration system is a reliable and ideal choice for the correction of tetracycline-stained teeth.</p>